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Sample records for 2xiib mirror machine

  1. Extreme ultraviolet diagnosis of a neutral-beam-heated mirror machine

    SciTech Connect

    Drake, R.P.

    1980-07-01

    Extreme ultraviolet emissions from the LLL 2XIIB fusion research experiment have been studied. (2XIIB was a magnetic-mirror-plasma-confinement device; beams of high-energy (20 keV) neutral deuterium created a high-density, high-temperature plasma.) A normal-incidence concave-grating monochromator, equipped with a windowless photomultiplier tube, was used to measure emissions in the spectral region from 400 Angstrom to 1600 A. Emissions of oxygen, titanium, carbon, nitrogen, and deuterium were identified; the oxygen brightnesses at times exceeded 10/sup 18/ ph-s/sup -1/-cm/sup -2/-sr/sup -1/. A survey of the emission characteristics found the oxygen concentration was 3%, the other impurities had concentrations near 0.4%. The radiated power loss was about 5% of the deposited neutral beam power.

  2. Alpha Channeling in Mirror Machines

    SciTech Connect

    Fisch N.J.

    2005-10-19

    Because of their engineering simplicity, high-β, and steady-state operation, mirror machines and related open-trap machines such as gas dynamic traps, are an attractive concept for achieving controlled nuclear fusion. In these open-trap machines, the confinement occurs by means of magnetic mirroring, without the magnetic field lines closing upon themselves within the region of particle confinement. Unfortunately, these concepts have not achieved to date very spectacular laboratory results, and their reactor prospects are dimmed by the prospect of a low Q-factor, the ratio of fusion power produced to auxiliary power. Nonetheless, because of its engineering promise, over the years numerous improvements have been proposed to enhance the reactor prospects of mirror fusion, such as tandem designs, end-plugging, and electric potential barriers.

  3. Evolution of the mirror machine

    SciTech Connect

    Damm, C. C.

    1983-08-18

    The history of the magnetic-mirror approach to a fusion reactor is primarily the history of our understanding and control of several crucial physics issues, coupled with progress in the technology of heating and confining a reacting plasma. The basic requirement of an MHD-stable plasma equilibrium was achieved following the early introduction of minimum-B multipolar magnetic fields. In refined form, the same magnetic-well principle carries over to our present experiments and to reactor designs. The higher frequency microinstabilities, arising from the non-Maxwellian particle distributions inherent in mirror machines, have gradually come under control as theoretical prescriptions for distribution functions have been applied in the experiments. Even with stability, the classical plasma leakage through the mirrors posed a serious question for reactor viability until the principle of electrostatic axial stoppering was applied in the tandem mirror configuration. Experiments to test this principle successfully demonstrated the substantial improvement in confinement predicted. Concurrent with advances in mirror plasma physics, development of both high-power neutral beam injectors and high-speed vacuum pumping techniques has played a crucial role in ongoing experiments. Together with superconducting magnets, cryogenic pumping, and high-power radiofrequency heating, these technologies have evolved to a level that extrapolates readily to meet the requirements of a tandem mirror fusion reactor.

  4. Alpha Channeling in Mirror Machines

    SciTech Connect

    Fisch, Nathaniel J.

    2014-07-16

    This Final Report for DE-FG02-06ER54851, Alpha Channeling in Mirror Machines, was in fact submitted on April 9, 2010. Some confusion arose because it was submitted as an initial progress report on a related grant, Alpha Channeling in Open- System Magnetic Devices. The original text is reproduced below, except that the publication record is undated. Note that the articles published in 2009 and 2010 reflect work in fact done under DE-FG02-06ER54851.

  5. Applying Alpha-Channeling to Mirror Machines

    SciTech Connect

    A.I. Zhmoginov and N.J. Fisch

    2012-03-16

    The α-channeling effect entails the use of radio-frequency waves to expel and cool high-energetic α- particles born in a fusion reactor; the device reactivity can then be increased even further by redirecting the extracted energy to fuel ions. Originally proposed for tokamaks, this technique has also been shown to benefi t open-ended fusion devices. Here, the fundamental theory and practical aspects of α- channeling in mirror machines are reviewed, including the influence of magnetic field inhomogeneity and the effect of a finite wave region on the α-channeling mechanism. For practical implementation of the α -channeling effect in mirror geometry, suitable contained weakly-damped modes are identifi ed. In addition, the parameter space of candidate waves for implementing the α -channeling effect can be signi cantly extended through the introduction of a suitable minority ion species that has the catalytic effect of moderating the transfer of power from the α-channeling wave to the fuel ions.

  6. Plasma-wall interactions in tandem mirror machines

    SciTech Connect

    Allen, S.L.

    1984-11-01

    A description is presented of the plasma-surface interactions in thermal-barrier tandem-mirror machines. The thermal-barrier mode of axial confinement is an integral part of a tandem mirror, and it dictates the required plasma conditions, particularly at the surface of the plasma. For this reason, a qualitative discussion of the thermal barrier is presented first in Section 2. A brief description of the experimental configuration used in tandem mirrors to create the thermal barrier is then examined in detail in Section 3; the TMX-U and MFTF-B machines are used as specific examples. In Section 4, the relevant plasma-surface interaction issues are addressed, and experimental results from currently operating tandom mirror machines are included. Section 5 is both a summary and a discussion of future work concerned with plasma-surface interactions in tandem mirrors.

  7. An Automatic Washing Machine to Remove Aluminum From Astronomical Mirrors

    NASA Astrophysics Data System (ADS)

    Zitelli, Valentina

    Cleaning of large astronomical mirrors, before aluminization, required in the past a large amount of manual operations on the surface. With very large mirrors, 8 meter or more, manual operations become time consuming, expensive and often dangerous, both for mirror surface and operators. A fully automated procedure is thus mandatory when handling large mirrors. To this aim we experimented on a small scale (60 cm) an automatic procedure, free from any manual contact with the mirror, capable of removing old aluminum and leaving a clean, wet surface ready for a successful new aluminization. First we manually treated small borosilicate mirrors, obtained from the LBT primary mirror glass batch, with different sequences of chemicals, commonly used to this purpose. These small mirrors were checked with a Wyko interferometer before and after treating, to trace change in roughness of the surface. Quality and stability of the new aluminum deposition after cleaning was also checked. The washing machine prototype is composed by a water proof box on rigid PVC with a moving arm, a pump and a series of tanks containing the used chemicals. All the adopted components can be used with acids and other corrosive fluids. The machine is designed to hold the mirror in vertical position. An arm with 10 cm spaced nozzles moves up and down in front of the mirror spraying the adopted chemicals in a defined sequence. A pump forces the liquid through the circuit. After the washing, the mirror is left, protected from the dust in the washing machine, for about 2 hours to drip the water, then is moved into the vacuum pump to check the final result of aluminizing the cleaned surface. A homogeneous layer of aluminum follows only after a careful cleaning, otherwise a fast oxidize process, or a inhomogeneous aluminum coating appear. Scaling times, fluxes and costs from this experiment to large size mirrors leads to realistic, affordable figures.

  8. Diamond machining of a single shot ellipsoidal focusing plasma mirror

    NASA Astrophysics Data System (ADS)

    Bourgenot, C.; Crosby, D. N.; Robertson, D. J.

    2016-11-01

    Plasma mirrors have become an important tool in high power laser physics due to their ability to suppress laser pre-pulses and amplified spontaneous emission allowing a cleaner and sharper rising edge pulse to be focused onto a target. A PMMA ellipsoidal plasma mirror used to increase the peak intensity of a high power laser pulses before it reaches the target is presented. The ellipse has been designed to increase by a factor 3, between input and output, the F-number of the beam, inducing in theory a factor 9 gain in peak intensity. Diamond machining, which is a technique capable of producing sub-micron accuracy on steep, freeform surfaces, is an ideal process for manufacturing these types of mirrors. In this paper, we discuss the diamond machining requirements to manufacture such near diffraction limited high numerical aperture mirrors.

  9. Waves for Alpha-Channeling in Mirror Machines

    SciTech Connect

    A. I. Zhmoginov and N. J. Fisch

    2009-07-08

    Alpha-channeling can, in principle, be implemented in mirror machines via exciting weaklydamped modes in the ion cyclotron frequency range with perpendicular wavelengths smaller than the alpha particle gyroradius. Assuming quasi-longitudinal or quasi-transverse wave propagation, we search systematically for suitable modes in mirror plasmas. Considering two device designs, a proof-of-principle facility and a fusion rector prototype, we in fact identify candidate modes suitable for alpha-channeling.

  10. Development of diamond machined mirror arrays for integral field spectroscopy

    NASA Astrophysics Data System (ADS)

    Lee, David; Wells, Martyn; Dickson, Colin J.; Shore, Paul; Morantz, Paul

    2006-06-01

    Recent advances in the design of all reflective integral field units have led engineers to look for new techniques to manufacture monolithic mirror arrays for use in such instruments. One such design is being developed at the UKATC for use on the Mid-Infrared Instrument (MIRI) on the James Webb Space telescope. The MIRI instrument will contain four integral field units with image slicer and re-imaging mirror arrays manufactured at Cranfield University. The mirror arrays have been designed with particular attention to the requirements of precision machining and subsequent metrology. The philosophy of "design for manufacture" has led to the production of mirror arrays with unrivalled levels of accuracy. Initially, this paper will describe the opto-mechanical design of the mirror arrays. The paper will then discuss the diamond turning manufacturing technique specially developed to machine these complex components. The paper will also describe the precision metrology capability developed specifically for the MIRI project that is used to accurately measure mirror locations and surface form errors. Finally, the paper will present the results obtained so far for the mirror arrays being prepared for the IFU verification model and prototype.

  11. Diamond Machining of an Off-Axis Biconic Aspherical Mirror

    NASA Technical Reports Server (NTRS)

    Ohl, Raymond G.; Preuss, Werner; Sohn, Alex; MacKenty, John

    2009-01-01

    Two diamond-machining methods have been developed as part of an effort to design and fabricate an off-axis, biconic ellipsoidal, concave aluminum mirror for an infrared spectrometer at the Kitt Peak National Observatory. Beyond this initial application, the methods can be expected to enable satisfaction of requirements for future instrument mirrors having increasingly complex (including asymmetrical), precise shapes that, heretofore, could not readily be fabricated by diamond machining or, in some cases, could not be fabricated at all. In the initial application, the mirror is prescribed, in terms of Cartesian coordinates x and y, by aperture dimensions of 94 by 76 mm, placements of -2 mm off axis in x and 227 mm off axis in y, an x radius of curvature of 377 mm, a y radius of curvature of 407 mm, an x conic constant of 0.078, and a y conic constant of 0.127. The aspect ratio of the mirror blank is about 6. One common, "diamond machining" process uses single-point diamond turning (SPDT). However, it is impossible to generate the required off-axis, biconic ellipsoidal shape by conventional SPDT because (1) rotational symmetry is an essential element of conventional SPDT and (2) the present off-axis biconic mirror shape lacks rotational symmetry. Following conventional practice, it would be necessary to make this mirror from a glass blank by computer-controlled polishing, which costs more than diamond machining and yields a mirror that is more difficult to mount to a metal bench. One of the two present diamond machining methods involves the use of an SPDT machine equipped with a fast tool servo (FTS). The SPDT machine is programmed to follow the rotationally symmetric asphere that best fits the desired off-axis, biconic ellipsoidal surface. The FTS is actuated in synchronism with the rotation of the SPDT machine to generate the difference between the desired surface and the best-fit rotationally symmetric asphere. In order to minimize the required stroke of the FTS

  12. Plasma Control in Symmetric Mirror Machines

    NASA Astrophysics Data System (ADS)

    Horton, W.; Rowan, W. L.; Alvarado, Igor; Fu, X. R.; Beklemishev, A. D.

    2014-10-01

    Plasma confinement in the symmetric rotating mirror plasma at the Budker Institute shows enhanced confinement with high electron temperatures with end plates biasing. Improved confinement is achieved by biasing end plate cells in the expansion tanks so as to achieve an inward pointing radial electric field. The negative potential well produces vortex plasma rotation similar to that in the negative potential well of Ohmic heated tokamaks. This plasma state has similarity with the lower turbulence level regimes documented in the Helimak where negative biasing of the end plates produces an inward radial electric field. To understand this vortex confinement we carry out 3D simulations with nonlinear partial differential equations for the electric potential and density in plasmas with an axially localized region of unfavorable and favorable magnetic curvature. The simulations show that the plasma density rapidly adjusts to be higher in the region of favorable curvature regions and remains relatively well confined while rapidly rotating. The results support the concept of using plasma-biasing electrodes in large expander tanks to achieve enhanced mirror plasma confinement. Supported by US-DoE grant to UT, LANL and the Budker Institute for Nuclear Physics.

  13. Feedback effect on flute dynamics in a mirror machine

    NASA Astrophysics Data System (ADS)

    Be'Ery, Ilan; Seemann, Omri

    2015-11-01

    Active feedback techniques may stabilize the flute instability in mirror traps and make them viable candidates for fusion machines. A fast feedback with optical sensors and electrical actuators was implemented in a table-top mirror machine and used to study several aspects of feedback stabilization. For a cold, dense plasma the feedback reduces dramatically the flute amplitude of the first two mode. For higher temperature plasma, a significant increase of plasma density due to feedback stabilization is also demonstrated. The effect of changing feedback gain and phase has some interesting feature such as asymmetry with respect to positive and negative phase shifts and non-monotonic dependence of flute amplitude on feedback gain. These effects are explained using simplified analytic model of the flute and feedback.

  14. Simulation of Alpha-Channeling in Mirror Machines

    SciTech Connect

    A.I. Zhmoginov, N.J. Fisch

    2008-03-17

    Applying α-channeling techniques to mirror machines can significantly increase their effective reactivity, thus making open configurations more advantageous for practical fusion. A large fraction of α particle energy can be extracted using rf waves. Effects employed to cool α particles can also in principle be used to heat the fusion ions; the possibility to design a configuration of rf waves which could be used to perform both tasks is demonstrated.

  15. Density increase due to active feedback in mirror machine

    NASA Astrophysics Data System (ADS)

    Seemann, Omri; Be'Ery, Ilan

    2014-10-01

    Mirror machines are one of the schemes for future fusion systems. Its main drawbacks are the flute instability and being open ended which results in plasma losses. A feedback system is used to stabilize the flute instability in a table top mirror machine with a continuous plasma source and RF heating. Under certain source density and temperature conditions, although the plasma was stabilized, plasma density increase was not measured. After decreasing the source density and increasing the temperature, Plasma density increase was achieved. It is theorized that these results are due to transition of the plasma main loss mechanism from collision dominated to instability dominated. In the former, the main density loss is through diffusion and In the latter, it is through flute instability which drives the plasma to the edge of the vacuum chamber. Future research directions are discussed for a planned machine which should achieve higher temperatures and better diagnostic capabilities. The research will focus on magnetic actuators and passive RF stabilization.

  16. Feedback effect on flute dynamics in a mirror machine

    NASA Astrophysics Data System (ADS)

    Be'ery, I.; Seemann, O.

    2015-08-01

    The effect of active feedback on flute instability is experimentally studied in a table-top mirror machine. Changing the plasma conditions from mirror-loss dominated to flute-loss dominated, it is demonstrated that while the feedback has no effect on plasma density in the first case, it increases the plasma density by up to 50% in the second case. Measurements of the dependence of instability amplitude on feedback gain show that large gain stimulates high frequency perturbations. The period of these perturbations corresponds to the inherent delay of immersed electrode feedback. Variation of the spatial phase between the input and output of the phase reveals a large asymmetry between positive and negative phase shifts. A simplified model is introduced to explain how a negative phase shift causes positive feedback between the external feedback and the centrifugally driven rotation.

  17. Feasibility Studies of Alpha-Channeling in Mirror Machines

    SciTech Connect

    A. I. Zhmoginov and N. J. Fisch

    2010-03-19

    The linear magnetic trap is an attractive concept both for fusion reactors and for other plasma applications due to its relative engineering simplicity and high-beta operation. Applying the α- channeling technique to linear traps, such as mirror machines, can benefit this concept by efficiently redirecting α particle energy to fuel ion heating or by otherwise sustaining plasma confinement, thus increasing the effective fusion reactivity. To identify waves suitable for α-channeling a rough optimization of the energy extraction rate with respect to the wave parameters is performed. After the optimal regime is identified, a systematic search for modes with similar parameters in mirror plasmas is performed, assuming quasi-longitudinal or quasi-transverse wave propagation. Several modes suitable for α particle energy extraction are identified for both reactor designs and for proof- of-principle experiments.

  18. Diamond machining of aspherical mirrors and mirror arrays for Integral Field Units: part II. Metrology

    NASA Astrophysics Data System (ADS)

    Rolt, Stephen; Robertson, David R.

    2008-07-01

    The application of freeform diamond machining techniques to the manufacture of precision optics for astronomical instrumentation has opened up a wide range of exciting new design possibilities. Freeform surfaces, not limited by symmetry considerations, and complex multi-faceted mirror arrays can be precisely machined. This capability has removed many constraints from the design process and has enabled the fulfilment of radical instrument designs. However, this flexibility poses a significant challenge for component characterisation. Accurate measurement of the form accuracy of surfaces lacking symmetry is particularly difficult using standard interferometric techniques. Furthermore, the accurate 3 dimensional characterisation of complex multi-faceted components presents an added challenge. The authors describe techniques that have been applied to the measurement of complex surfaces in Integral Field Units (IFUs). In particular, we present novel approaches for the measurement of the form of complex non-radially symmetric surfaces to an accuracy of a few nanometres. These measurements use a Twyman-Green Interferometer configured in a variety of non-standard arrangements. In addition, the authors consider the difficulties in the measurement of multifaceted surfaces, and the accurate determination of the geometric relations between these surfaces. The authors discuss the use of confocal gauge techniques in the characterisation of these surfaces.

  19. Plasma confinement experiments in the TMX tandem mirror. Paper IAEA-CN-38/F-1

    SciTech Connect

    Simonen, T.C.; Anderson, C.A.; Casper, T.A.

    1980-05-22

    Results from the new Tandem Mirror Experiment (TMX) are described. Tandem-mirror density and potential profiles are produced using end-plug neutral-beam injection and central-cell gas-fueling. TMX parameters are near those predicted theoretically. The end-plug electron temperature is higher than in the comparably sized single-mirror 2XIIB. Axial confinement of the finite-beta central-cell plasma is improved by the end plugs by as much as a factor of 9. In TMX, end-plug microinstability limits central-cell confinement in agreement with theory.

  20. Machine Protection System for the Stepper Motor Actuated SyLMAND Mirrors

    SciTech Connect

    Subramanian, V. R.; Dolton, W.; Wells, G.; Hallin, E.; Achenbach, S.; Klymyshyn, D. M.; Augustin, M.

    2010-06-23

    SyLMAND, the Synchrotron Laboratory for Micro and Nano Devices at the Canadian Light Source, consists of a dedicated X-ray lithography beamline on a bend magnet port, and process support laboratories in a clean room environment. The beamline includes a double mirror system with flat, chromium-coated silicon mirrors operated at varying grazing angles of incidence (4 mrad to 45 mrad) for spectral adjustment by high energy cut-off. Each mirror can be independently moved by two stepper motors to precisely control the pitch and vertical position. We present in this paper the machine protection system implemented in the double mirror system to allow for safe operation of the two mirrors and to avoid consequences of potential stepper motor malfunction.

  1. Study on machining deformation of the ultra-thin mirror

    NASA Astrophysics Data System (ADS)

    Zhang, Hao; Wang, Peng

    2016-10-01

    In shape processing of the ultra-thin mirror, deformation will be produced under cutting forces, which is a major cause of quality deterioration. An ultra-thin mirror with diameter-thickness ratio more than 10 is studied in this paper. Rigidity characteristic of the grinding process by diamond wheel is analyzed by FEM. A receptance model of the micro-cutting process and the surface accuracy is established by a self-adaptive multi-scale method according the first strength method. And the effectiveness of the mathematical model is verified by experience. And the dynamic stiffness caused by grinding is optimized. As a result, deformation of the optical surface is reduced to 0.004λ and the acceptable surface accuracy can be achieved.

  2. Generalized energy principle for flute perturbations in axisymmetric mirror machines

    SciTech Connect

    Lansky, I.M.; Ryutov, D.D.

    1993-01-20

    Axial symmetry is a very desirable property of the mirror devices both for fusion and neutron source applications. The main obstacle to be circumvented in the development of such systems, is the flute instability of axisymmetric mirrors. In recent years there appeared a number of proposals, devoted to the stabilization of the flute perturbations in the framework of axisymmetric magnetic configurations, which are based on the combining of the MHD unstable central cell with various types of end-cell stabilizers. In the present paper we concentrate ourselves just on this scheme, including long solenoid with a uniform field, conjugated with the end stabilizing anchor, intended to provide MHD stability of the system as a whole. The attractive feature of such a configuration is that it allows to exploit finite larmor radius (FLR) effects for the stabilization of the flute perturbations. As is well known, FLR effects, being strong, stabilize all flute modes, except the one with azimuthal number m = 1, corresponding to the ``rigid`` displacement of the plasma column (the ``global`` mode). Consequently, in the conditions when FLR effects dominate, the anchor has to stabilize the ``global` mode only. Bearing in mind a favorable influence of FLR effects we, however, don`t restrict our paper by discussion of only ``global`` mode stability and consider a general case of an arbitrary azimuthal mode.

  3. Demonstration of Minimally Machined Honeycomb Silicon Carbide Mirrors

    NASA Technical Reports Server (NTRS)

    Goodman, William

    2012-01-01

    Honeycomb silicon carbide composite mirrors are made from a carbon fiber preform that is molded into a honeycomb shape using a rigid mold. The carbon fiber honeycomb is densified by using polymer infiltration pyrolysis, or through a reaction with liquid silicon. A chemical vapor deposit, or chemical vapor composite (CVC), process is used to deposit a polishable silicon or silicon carbide cladding on the honeycomb structure. Alternatively, the cladding may be replaced by a freestanding, replicated CVC SiC facesheet that is bonded to the honeycomb. The resulting carbon fiber-reinforced silicon carbide honeycomb structure is a ceramic matrix composite material with high stiffness and mechanical strength, high thermal conductivity, and low CTE (coefficient of thermal expansion). This innovation enables rapid, inexpensive manufacturing. The web thickness of the new material is less than 1 millimeter, and core geometries tailored. These parameters are based on precursor carbon-carbon honeycomb material made and patented by Ultracor. It is estimated at the time of this reporting that the HoneySiC(Trademark) will have a net production cost on the order of $38,000 per square meter. This includes an Ultracor raw material cost of about $97,000 per square meter, and a Trex silicon carbide deposition cost of $27,000 per square meter. Even at double this price, HoneySiC would beat NASA's goal of $100,000 per square meter. Cost savings are estimated to be 40 to 100 times that of current mirror technologies. The organic, rich prepreg material has a density of 56 kilograms per cubic meter. A charred carbon-carbon panel (volatile organics burnt off) has a density of 270 kilograms per cubic meter. Therefore, it is estimated that a HoneySiC panel would have a density of no more than 900 kilograms per cubic meter, which is about half that of beryllium and about onethird the density of bulk silicon carbide. It is also estimated that larger mirrors could be produced in a matter of weeks

  4. Hardware Photos: Image Showing JWST Engineering Demonstration Mirror, Mounted Ready for Machining at AXYS and Image Showing HIP Can Containing Light Mirrors 1 and 2 Ready for Mirror Fabrication

    NASA Technical Reports Server (NTRS)

    OKeefe, Sean

    2004-01-01

    The images in this viewgraph presentation have the following captions: 1) EDU mirror after being sawed in half; 2) EDU Delivered to Axsys; 3) Be EDU Blank Received and Machining Started; 4) Loaded HIP can for flight PM segments 1 and 2; 5) Flight Blanks 1 and 2 Loaded into HIP Can at Brush-Wellman; 6) EDU in Machining at Axsys.

  5. New machining and testing method of large angle infrared wedge mirror parts

    NASA Astrophysics Data System (ADS)

    Su, Ying; Guo, Rui; Zhang, Fumei; Zhang, Zheng; Liu, Xuanmin; Zengqi, Xu; Li, Wenting; Zhang, Feng

    2016-10-01

    Large angle wedge parts were widely used in the optical system that was used for achieving a wide range of scanning. Due to the parts having the characteristic of large difference in the thickness of both ends and high density, the accuracy of the wedge angle was hard to ensure to reach second level in optical processing. Generally, wedge mirror angle was measured by contact comparison method which was easy to damage the surface. In view of the existence of two practical problems, in this paper, based on theoretical analysis, by taking three key measures that were the accurate positioning for the central position of the large angle wedge part, the accuracy control of angle precision machined of wedge mirror and fast and non destructive laser assisted absolute measurement of large angle wedge, the qualified rate of parts were increased to 100%, a feasible, controllable and efficient process route for large angle infrared wedge parts was found out.

  6. Automation and control system for the PUPR Mirror/Cusp plasma machine

    NASA Astrophysics Data System (ADS)

    Molina, O.; Morales, E.; Gonzalez-Lizardo, A.; Leal-Quirós, E.

    2008-10-01

    The automation of the PUPR Mirror/Cusp (M/C) plasma machine is the result of a collaboration between the Polytechnic University of Puerto Rico, NASA and Johns Hopkins University's Applied Physics Laboratory for the NASA Solar Probe mission. The PUPR M/C plasma machine is the only machine of its type in the Caribbean that has been set up for automatic operation. It valves and pumps together with a current source and microwave generator to create plasma. This process requires the operator to do a series of strict steps while constantly monitoring the pressure and temperature. This process was automated using a programmable logic controller (PLC). The PLC manages all the equipment used to make plasma, and communicates with the vacuum-measuring system and the cooling temperature control system to acquire the state of the system and determine the next step in the process of making plasma. The machine operation can be switched between manual and automatic mode, allowing the operator to take control of the operation at any moment. The system has improved the speed and precision of the operations at the Plasma Engineering Laboratory of the Polytechnic University of Puerto Rico, by eliminating most of the possible human errors in the operation of the plasma device.

  7. Determination Of Plasma Parameters In The PUPR Mirror and Cusp Plasma Machine Via Electrostatic Probe Methods

    SciTech Connect

    Meyer, Ryan M.; Rivera, Miguel A.; Colmenares, Franklyn; Leal, David; Rivera, Ramon; Leal-Quiros, Edbertho; Gonzales, Angel

    2006-12-04

    Electrostatic probes are constructed for the PUPR Mirror and Cusp Plasma Machine and preliminary measurements of the plasma parameters are obtained. The machine is cylindrical in shape with two copper coils wound around the machine to provide the necessary mirror or cusp field configuration. The plasma is heated using the electron cyclotron heating method at a frequency of 2.45 GHz. I-V characteristics are obtained using single, double, and emissive Langmuir probes in Argon plasma at approximately 1*10-4 Torr and with approximate field strength of {approx} 0.1T at the point cusp. The single and double Langmuir probes consist of 3.5 mm radius stainless steel disks. Characteristics are obtained for the single and double Langmuir probes using a source meter and programming a voltage sweep while recording the current from the digital readout. The emissive probe is constructed by using a tungsten filament and characteristics are obtained in a manner similar to that described for the single and double Langmuir probes. An emission current is superposed on top of the sweeping signal using a DC power source. An electron temperature of approximately 7.5eV is observed in the plasma at a density of {approx}4.0*1014m-3 using the single Langmuir probe. In addition, with the distribution function obtained from the single probe, the plasma potential is observed to be approximately 25-30V. The measurement of 25-30V for the plasma potential is supported by measurements obtained from the emissive probe.

  8. Design, Fabrication, Optical Testing, and Performance of Diamond Machined Aspheric Mirrors for Ground-Based Near-IR Astronomy

    NASA Technical Reports Server (NTRS)

    Ohl, Raymond G.; Mink, Ronald; Chambers, V. John; Connelly, Joseph A.; Mentzell, J. Eric; Tveekrem, June L.; Howard, Joseph M.; Preuss, Werner; Schroeder, Mechthild; Sohn, Alex; Krebs, Carolyn (Technical Monitor)

    2002-01-01

    Challenges in fabrication and testing have historically limited the choice of surfaces available for the design of reflective optical instruments. Spherical and conic mirrors are common, but, for future science instruments, more degrees of freedom are necessary to meet challenging performance and packaging requirements. These instruments will be composed of unusual aspheres located far off-axis with large spherical departure, and some designs will require asymmetric surface profiles. In particular, single-surface astigmatism correction in spectrographs necessitates a toroidal surface, which lacks an axis of rotational symmetry. We describe the design, fabrication, optical testing, and performance of three rotationally symmetric, off-axis, aspheric mirrors and one toroidal, off-axis, biconic camera mirror on aluminum substrates for the Infrared Multi-Object Spectrograph (IRMOS) instrument. IRMOS is a facility instrument for the Kitt Peak National Observatory's Mayall Telescope (3.8 m) and an engineering prototype for a possible design of the Next Generation Space Telescope/Multi-Object Spectrograph. The symmetric mirrors range in aperture from 94x86 mm to 286x269 mm and in f-number from 0.9 to 2.4. They are various off-axis, convex and concave, prolate and oblate ellipsoids. The concave biconic mirror has a 94x76 mm aperture, Rx=377 mm, kx=0.0778, Ry=407 mm, and ky=0.1265 and is decentered. by -2 mm in x and 227 mm in y. The mirrors have an aspect ratio of approximately 4:1. The surface error fabrication tolerances are less than 63.3 nm RMS figure error and less than 10 nm RMS microroughness. The mirrors are attached to the instrument bench via a semi-kinematic, integral flexure mount. We describe mirror design, diamond machining, the results of figure testing using computer-generated holograms, and imaging and scattered light modeling and performance.

  9. Determination of Local Magnetic Dipole Moment of the Plasma at the PUPR Cusp-Mirror Machine

    SciTech Connect

    Leal-Quiros, Edbertho; Prelas, Mark

    2006-12-04

    A novel diagnostic that allows measurement of the magnetic moment {mu} has been designed. The {mu}-Analyzer consists of a Directional Energy Analyzer and a Magnetic Hall Probe in the same detector miniature case. The Directional Energy Analyzer measures the ion temperature in the perpendicular direction to the magnetic field. On the other side, the Hall Probe measures the magnetic field. The {mu}-Analyzer is a miniature analyzer to avoid plasma perturbation. This allows the measurement of the ion temperature and the local magnetic field at the same point at the same time, therefore {mu}, the first adiabatic invariant is found. From the above parameters, the local Larmor radius also will be calculated. From the analysis of the data simultaneously in time and space, the {mu} of the Local Plasma has been determined. This result is a very important quantity, among other properties that permit one to know the stability of the magnetic confinement device using the MHD Stability Criterium, and also very important in Space Plasma Research. In addition to the above, a direct measurement of the Larmor radius of each position is also possible. The experiments have been made in a Cusp/Mirror Plasma Machine where plasma parameters such as Density and Temperature are relatively easy to change in a very wide range.

  10. Development of a numerically controlled elastic emission machining system for fabricating mandrels of ellipsoidal focusing mirrors used in soft x-ray microscopy

    NASA Astrophysics Data System (ADS)

    Takei, Yoshinori; Kume, Takehiro; Motoyama, Hiroto; Hiraguri, Kentaro; Hashizume, Hirokazu; Mimura, Hidekazu

    2013-09-01

    Ellipsoidal mirrors are one of the most promising types of X-ray mirror, because the mirror can focus X-rays to nanometer size with a large aperture and no chromatic aberration. However, so far ideal ellipsoidal mirrors cannot be realized by any manufacturing methods. One of the reasons is there is no fabrication method to process their inside surface with a diameter of several millimeters with nanometer-level accuracy. We propose and develop a manufacturing process of the ellipsoidal mirror. First, a master which has the reversed shape is prepared using grinding, polishing and Elastic Emission Machining (EEM). EEM can finish the surface shape to within 2nm (RMS). Then, the ellipsoidal mirror is produced by replicating the surface using an electroforming deposition method. By conducting the process without any stress at room temperature, replicating the surface roughness and shape with nanometer order accuracy is possible. In this paper, we report the current status of manufacturing of the ellipsoidal mirror.

  11. Optical Testing of Diamond Machined, Aspheric Mirrors for Groundbased, Near-IR Astronomy

    NASA Technical Reports Server (NTRS)

    Chambers, V. John; Mink, Ronald G.; Ohl, Raymond G.; Connelly, Joseph A.; Mentzell, J. Eric; Arnold, Steven M.; Greenhouse, Matthew A.; Winsor, Robert S.; MacKenty, John W.

    2002-01-01

    The Infrared Multi-Object Spectrometer (IRMOS) is a facility-class instrument for the Kitt Peak National Observatory 4 and 2.1 meter telescopes. IRMOS is a near-IR (0.8-2.5 micron) spectrometer and operates at approximately 80 K. The 6061-T651 aluminum bench and mirrors constitute an athermal design. The instrument produces simultaneous spectra at low- to mid-resolving power (R=lambda/delta lambda= 300-3000) of approximately 100 objects in its 2.8 x 2.0 arcmin field. We describe ambient and cryogenic optical testing of the IRMOS mirrors across a broad range in spatial frequency (figure error, mid-frequency error, and microroughness). The mirrors include three rotationally symmetric, off-axis conic sections, one off-axis biconic, and several flat fold mirrors. The symmetric mirrors include convex and concave prolate and oblate ellipsoids. They range in aperture from 94x86 mm to 286x269 mm and in f-number from 0.9 to 2.4. The biconic mirror is concave and has a 94x76 mm aperture, R(sub x)=377 mm, k(sub x)=0.0778, R(sub y)=407 mm, and k(sub y)=0.1265 and is decentered by -2 mm in X and 227 mm in Y. All of the mirrors have an aspect ratio of approximately 6:1. The surface error fabrication tolerances are less than 10 nm RMS microroughness, 'best effort' for mid-frequency error, and less than 63.3 nm RMS figure error. Ambient temperature (approximately 293 K) testing is performed for each of the three surface error regimes, and figure testing is also performed at approximately 80 K. Operation of the ADE Phaseshift MicroXAM white light interferometer (micro-roughness) and the Bauer Model 200 profilometer (mid-frequency error) is described. Both the sag and conic values of the aspheric mirrors make these tests challenging. Figure testing is performed using a Zygo GPI interferometer, custom computer generated holograms (CGH), and optomechanical alignment fiducials. Cryogenic CGH null testing is discussed in detail. We discuss complications such as the change in

  12. Amorphous Metals and Composites as Mirrors and Mirror Assemblies

    NASA Technical Reports Server (NTRS)

    Hofmann, Douglas C. (Inventor); Davis, Gregory L. (Inventor); Agnes, Gregory S. (Inventor); Shapiro, Andrew A. (Inventor)

    2016-01-01

    A mirror or mirror assembly fabricated by molding, pressing, assembling, or depositing one or more bulk metal glass (BMG), bulk metal glass composite (BMGMC), or amorphous metal (AM) parts and where the optical surface and backing of the mirror can be fabricated without machining or polishing by utilizing the unique molding capabilities of this class of materials.

  13. Refurbishment of solar simulation optical train mirror assemblies

    NASA Technical Reports Server (NTRS)

    Leverton, W. R.

    1973-01-01

    Mirror refurbishment processing is described, and the results of processing 251 mirror assemblies are reported. The mirror replica bonding, optical tests, electrical discharge machining, and vacuum coating are discussed.

  14. Controllable Mirror Devices

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A deformable Mirror Device (DMD) is a type of spatial light modulator in which mirrors fabricated monolithically on a silicon chip are deformed, or tilted, under electronic control to change the direction of light that falls upon the mirror. NASA and Texas Instruments (TI) have worked to develop this technology, which has subsequently been commercialized by TI. Initial application is the DMD 2000 Travel Information Printer for high speed, high volume printing of airline tickets and boarding passes. Other possible applications range from real-time object tracking to advanced industrial machine vision systems.

  15. Virtual Mirrors

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2010-01-01

    The multiple-reflection photograph in Fig. 1 was taken in an elevator on board the cruise ship Norwegian Jade in March 2008. Three of the four walls of the elevator were mirrored, allowing me to see the combination of two standard arrangements of plane mirrors: two mirrors set at 90 degrees to each other and two parallel mirrors. Optical phenomena…

  16. Virtual Mirrors

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2010-01-01

    The multiple-reflection photograph in Fig. 1 was taken in an elevator on board the cruise ship Norwegian Jade in March 2008. Three of the four walls of the elevator were mirrored, allowing me to see the combination of two standard arrangements of plane mirrors: two mirrors set at 90° to each other and two parallel mirrors. Optical phenomena of this complexity are most easily approached by the Method of Virtual Mirrors.

  17. Mirror mount

    DOEpatents

    Kuklo, Thomas C.; Bender, Donald A.

    1994-01-01

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for "X" and "Y" tilts of the mirror only. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time.

  18. Einstein's Mirror

    ERIC Educational Resources Information Center

    Gjurchinovski, Aleksandar; Skeparovski, Aleksandar

    2008-01-01

    Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity. The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a…

  19. Chiral mirrors

    SciTech Connect

    Plum, Eric; Zheludev, Nikolay I.

    2015-06-01

    Mirrors are used in telescopes, microscopes, photo cameras, lasers, satellite dishes, and everywhere else, where redirection of electromagnetic radiation is required making them arguably the most important optical component. While conventional isotropic mirrors will reflect linear polarizations without change, the handedness of circularly polarized waves is reversed upon reflection. Here, we demonstrate a type of mirror reflecting one circular polarization without changing its handedness, while absorbing the other. The polarization-preserving mirror consists of a planar metasurface with a subwavelength pattern that cannot be superimposed with its mirror image without being lifted out of its plane, and a conventional mirror spaced by a fraction of the wavelength from the metasurface. Such mirrors enable circularly polarized lasers and Fabry-Pérot cavities with enhanced tunability, gyroscopic applications, polarization-sensitive detectors of electromagnetic waves, and can be used to enhance spectroscopies of chiral media.

  20. Micromachined mirrors

    NASA Astrophysics Data System (ADS)

    Conant, Robert Alan

    This dissertation discusses the fundamental limits of scanning mirror design, focusing on the limitations due to the interaction between mechanical properties (mirror flatness and dynamic deformation), and optical properties (beam divergence and optical resolution). The performance criteria for both resonant-scanning mirrors and steady-state, beam-positioning mirrors are related to the mirror geometries, desired optical resolution, material properties, and mechanical resonant frequencies. The optical resolution of the scanning mirror is linearly dependent on the mirror length, so longer mirrors should provide higher-resolution scanners. However, when undergoing an angular acceleration mirrors exhibit dynamic deformation, which is shown to be proportional to the fifth power of the length. Two different implementations of MEMS scanning mirrors are presented: polysilicon surface-micromachined mirrors and a new design we call the Staggered Torsional Electrostatic Combdrive (STEC) micromirror. The surface-micromachined mirrors are shown to be capable of reliable operation, but they have significant performance limitations caused by the limited thickness obtainable with the LPCVD-polysilicon structures. Calculations show that surface-micromachined mirrors of thickness 1.5 mum and diameter 550 mum are only capable of scanning +/-10 degrees at 251 Hz while retaining diffraction-limited optical performance. The STEC micromirrors, designed to overcome the limitations of the surface-micromachined mirrors, are capable of much higher-speed scanning (up to 61 kHz) without performance-limiting dynamic deformation of the mirror surface. The STEC micromirror fabrication process is extended to create Tensile Optical Surface (TOS) micromirrors---mirrors with thick silicon rib support structures and thin membranes that provide the reflective surface. An application of scanning mirrors is presented: a raster-scanning video display. This demonstration uses two surface

  1. Castable Amorphous Metal Mirrors and Mirror Assemblies

    NASA Technical Reports Server (NTRS)

    Hofmann, Douglas C.; Davis, Gregory L.; Agnes, Gregory S.; Shapiro, Andrew A.

    2013-01-01

    A revolutionary way to produce a mirror and mirror assembly is to cast the entire part at once from a metal alloy that combines all of the desired features into the final part: optical smoothness, curvature, flexures, tabs, isogrids, low CTE, and toughness. In this work, it has been demonstrated that castable mirrors are possible using bulk metallic glasses (BMGs, also called amorphous metals) and BMG matrix composites (BMGMCs). These novel alloys have all of the desired mechanical and thermal properties to fabricate an entire mirror assembly without machining, bonding, brazing, welding, or epoxy. BMGs are multi-component metal alloys that have been cooled in such a manner as to avoid crystallization leading to an amorphous (non-crystalline) microstructure. This lack of crystal structure and the fact that these alloys are glasses, leads to a wide assortment of mechanical and thermal properties that are unlike those observed in crystalline metals. Among these are high yield strength, carbide-like hardness, low melting temperatures (making them castable like aluminum), a thermoplastic processing region (for improving smoothness), low stiffness, high strength-to-weight ratios, relatively low CTE, density similar to titanium alloys, high elasticity and ultra-smooth cast parts (as low as 0.2-nm surface roughness has been demonstrated in cast BMGs). BMGMCs are composite alloys that consist of a BMG matrix with crystalline dendrites embedded throughout. BMGMCs are used to overcome the typically brittle failure observed in monolithic BMGs by adding a soft phase that arrests the formation of cracks in the BMG matrix. In some cases, BMGMCs offer superior castability, toughness, and fatigue resistance, if not as good a surface finish as BMGs. This work has demonstrated that BMGs and BMGMCs can be cast into prototype mirrors and mirror assemblies without difficulty.

  2. Mirror agnosia.

    PubMed

    Ramachandran, V S; Altschuler, E L; Hillyer, S

    1997-05-22

    Normal people rarely confuse the mirror image of an object with a real object so long as they realize they are looking into a mirror. We report a new neurological sign, 'mirror agnosia', following right parietal lesions in which this ability is severely compromised. We studied four right hemisphere stroke patients who had left visual field 'neglect'. i.e. they were indifferent to objects in their left visual field even though they were not blind. We then placed a vertical parasagittal mirror on each patients' right so that they could clearly see the reflection of objects placed in the (neglected) visual field. When shown a candy or pen on their left, the patients kept banging their hand into the mirror or groped behind it attempting to grab the reflection; they did not reach for the real object on the left, even though they were mentally quite lucid and knew they were looking into a mirror. Remarkably, all four patients kept complaining that the object was 'in the mirror', 'outside my reach' or 'behind the mirror'. Thus, even the patients' ability to make simple logical inferences about mirrors has been selectively warped to accommodate the strange new sensory world that they now inhabit. The finding may have implications for understanding how the brain creates representations of mirror reflections.

  3. Mirror agnosia.

    PubMed Central

    Ramachandran, V S; Altschuler, E L; Hillyer, S

    1997-01-01

    Normal people rarely confuse the mirror image of an object with a real object so long as they realize they are looking into a mirror. We report a new neurological sign, 'mirror agnosia', following right parietal lesions in which this ability is severely compromised. We studied four right hemisphere stroke patients who had left visual field 'neglect'. i.e. they were indifferent to objects in their left visual field even though they were not blind. We then placed a vertical parasagittal mirror on each patients' right so that they could clearly see the reflection of objects placed in the (neglected) visual field. When shown a candy or pen on their left, the patients kept banging their hand into the mirror or groped behind it attempting to grab the reflection; they did not reach for the real object on the left, even though they were mentally quite lucid and knew they were looking into a mirror. Remarkably, all four patients kept complaining that the object was 'in the mirror', 'outside my reach' or 'behind the mirror'. Thus, even the patients' ability to make simple logical inferences about mirrors has been selectively warped to accommodate the strange new sensory world that they now inhabit. The finding may have implications for understanding how the brain creates representations of mirror reflections. PMID:9178535

  4. Mirror mount

    DOEpatents

    Kuklo, T.C.; Bender, D.A.

    1994-10-04

    A unique lens or mirror mount having adjustable constraints at two key locations to allow for ''X'' and ''Y'' tilts of the mirror only is disclosed. The device uses two pair of flexures of a type such that the pivots of the mirror gimble are rigidly fixed in all planes allowing the device to have zero stacking tolerance and zero wear over time. 4 figs.

  5. Helically linked mirror arrangement

    SciTech Connect

    Ranjan, P.

    1986-08-01

    A scheme is described for helical linking of mirror sections, which endeavors to combine the better features of toroidal and mirror devices by eliminating the longitudinal loss of mirror machines, having moderately high average ..beta.. and steady state operation. This scheme is aimed at a device, with closed magnetic surfaces having rotational transform for equilibrium, one or more axisymmetric straight sections for reduced radial loss, a simple geometrical axis for the links and an overall positive magnetic well depth for stability. We start by describing several other attempts at linking of mirror sections, made both in the past and the present. Then a description of our helically linked mirror scheme is given. This example has three identical straight sections connected by three sections having helical geometric axes. A theoretical analysis of the magnetic field and single-particle orbits in them leads to the conclusion that most of the passing particles would be confined in the device and they would have orbits independent of pitch angle under certain conditions. Numerical results are presented, which agree well with the theoretical results as far as passing particle orbits are concerned.

  6. White Light Focusing Mirror

    NASA Astrophysics Data System (ADS)

    Johnson, Eric; Lyndaker, Aaron; Deyhim, Alex; Sullivan, Michael; Chance, Mark; Abel, Don; Toomey, John; Hulbert, Steven

    2007-01-01

    The NSLS X28C white-light beamline is being outfitted with a focusing mirror in order to increase, as well as control, the x-ray intensity at the sample position. The new mirror is a 50 mm × 100 mm × 1100 mm single crystal silicon cylindrical 43.1mm radius substrate bendable to a toroid from infinite to 1200 m radius. The unique feature of this mirror system is the dual use of Indalloy 51 as both a mechanism for heat transfer and a buoyant support to negate the effects of gravity. The benefit of the liquid metal support is the ability to correct for minor slope errors that take the form of a parabola. A bobber mechanism is employed to displace the fluid under the mirror +/- 1.5 mm. This allows RMS slope error correction on the order of 2 urad. The unique mounting of the mirror ensures the contributions to slope error from errant mechanical stresses due to machining tolerances are virtually non-existent. After correction, the surface figure error (measured minus ideal) is <= 0.5 urad rms.

  7. Magic Mirrors

    ERIC Educational Resources Information Center

    Mills, Allan

    2011-01-01

    "Magic mirrors" were so named because, when they were positioned to throw a reflected patch of sunlight on a nearby wall, this area contained an outline of a design cast on the back of the (bronze) mirror. Investigations begun in the 19th century showed that this was a response to heavy localized pressures exerted on the face of the thin mirror…

  8. Slumped mirrors

    NASA Astrophysics Data System (ADS)

    Pteancu, Mircea; Dragan, Dorin; Dragan, Olivier; Miron, Andrei; Stanescu, Octavian

    2008-02-01

    The authors discusse the construction of slumped mirrors, their fabrication and testing (polishing and lapping). An important topic of the discussion is thermal fabrication of mirrors by using of matrixes. One of the authors of the entry is combining astronomy and aquariums construction.

  9. Einstein's Mirror

    NASA Astrophysics Data System (ADS)

    Gjurchinovski, Aleksandar; Skeparovski, Aleksandar

    2008-10-01

    Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity.1-4 The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a constant velocity.5 Einstein showed an intriguing fact that the usual law of reflection would not hold in the case of a uniformly moving mirror, that is, the angles of incidence and reflection of the light would not equal each other. Later on, it has been shown that the law of reflection at a moving mirror can be obtained in various alternative ways,6-10 but none of them seems suitable for bringing this interesting subject into the high school classroom.

  10. Mirror mount

    DOEpatents

    Humpal, Harold H.

    1987-01-01

    A mirror mount (10) is provided that allows free pitch, yaw and roll motion of the mirror (28) while keeping the location of a point (56) on the surface of the mirror (28) fixed in the rest frame of reference of the mount (10). Yaw movement is provided by two yaw cylinders (30,32) that are bearing (52) mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell (42) that is air bearing (72,74) mounted to move between a clamp (60) and an upper pedestal bearing (44). The centers of curvature of the spherical surfaces of the shell (42) lie upon the point (56). Pitch motion and roll motion are separately and independently imparted to mirror (28) by a pair of pitch paddles (34) and a pair of roll paddles (36) that are independently and separately moved by control rods (76,80) driven by motors (78,82).

  11. Mirror mount

    DOEpatents

    Humpal, H.H.

    1986-03-21

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors.

  12. Mirror mount

    DOEpatents

    Humpal, H.H.

    1987-11-10

    A mirror mount is provided that allows free pitch, yaw and roll motion of the mirror while keeping the location of a point on the surface of the mirror fixed in the rest frame of reference of the mount. Yaw movement is provided by two yaw cylinders that are bearing mounted to provide rotation. Pitch and roll motion is provided by a spherically annular shell that is air bearing mounted to move between a clamp and an upper pedestal bearing. The centers of curvature of the spherical surfaces of the shell lie upon the point. Pitch motion and roll motion are separately and independently imparted to mirror by a pair of pitch paddles and a pair of roll paddles that are independently and separately moved by control rods driven by motors. 5 figs.

  13. Hexagonal Mirror Array

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for solar the concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine, that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.

  14. Hexagonal Mirror Array

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for the solar concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.

  15. Mirror Technology

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Under a NASA contract, MI-CVD developed a process for producing bulk silicon carbide by means of a chemical vapor deposition process. The technology allows growth of a high purity material with superior mechanical/thermal properties and high polishability - ideal for mirror applications. The company employed the technology to develop three research mirrors for NASA Langley and is now marketing it as CVD SILICON CARBIDE. Its advantages include light weight, thermal stability and high reflectivity. The material has nuclear research facility applications and is of interest to industrial users of high power lasers.

  16. Conicoid Mirrors

    ERIC Educational Resources Information Center

    Castano, Diego J.; Hawkins, Lawrence C.

    2011-01-01

    The first-order equation relating object and image location for a mirror of arbitrary conic-sectional shape is derived. It is also shown that the parabolic reflecting surface is the only one free of aberration and only in the limiting case of distant sources. (Contains 3 figures.)

  17. Mirror Support

    NASA Technical Reports Server (NTRS)

    Baron, Richard L. (Inventor)

    2013-01-01

    Disclosed herein is a method of making a mirror support comprising a composite, the composite comprising a plurality of carbon nanotubes, wherein at least two of the plurality of carbon nanotubes are bonded to each other through a bridging moiety bound to each of the two carbon nanotubes, and a laminate comprising the composite.

  18. Mirror, Mirror, on the Wall.

    ERIC Educational Resources Information Center

    Flowers, Jim; Rose, M. Annette

    1998-01-01

    Students use tables of anthropometric data, their own measurements, underlying principles of physics, and math to solve a problem. The problem is to determine the height of a wall mirror, and where to mount it, so that 90% of the clientele can view their entire length without stretching or bending. (Author)

  19. Mirror monochromator

    SciTech Connect

    Mankos, Marian; Shadman, Khashayar

    2014-12-02

    In this SBIR project, Electron Optica, Inc. (EOI) is developing a mirror electron monochromator (MirrorChrom) attachment to new and retrofitted electron microscopes (EMs) for improving the energy resolution of the EM from the characteristic range of 0.2-0.5 eV to the range of 10-50 meV. This improvement will enhance the characterization of materials by imaging and spectroscopy. In particular, the monochromator will refine the energy spectra characterizing materials, as obtained from transmission EMs [TEMs] fitted with electron spectrometers, and it will increase the spatial resolution of the images of materials taken with scanning EMs (SEMs) operated at low voltages. EOI’s MirrorChrom technology utilizes a magnetic prism to simultaneously deflect the electron beam off the axis of the microscope column by 90° and disperse the electrons in proportional to their energies into a module with an electron mirror and a knife-edge. The knife-edge cuts off the tails of the energy distribution to reduce the energy spread of the electrons that are reflected, and subsequently deflected, back into the microscope column. The knife-edge is less prone to contamination, and thereby charging, than the conventional slits used in existing monochromators, which improves the reliability and stability of the module. The overall design of the MirrorChrom exploits the symmetry inherent in reversing the electron trajectory in order to maintain the beam brightness – a parameter that impacts how well the electron beam can be focused downstream onto a sample. During phase I, EOI drafted a set of candidate monochromator architectures and evaluated the trade-offs between energy resolution and beam current to achieve the optimum design for three particular applications with market potential: increasing the spatial resolution of low voltage SEMs, increasing the energy resolution of low voltage TEMs (beam energy of 5-20 keV), and increasing the energy resolution of conventional TEMs (beam

  20. Mirror systems

    SciTech Connect

    Howells, M.R.

    1985-12-01

    The physics of VUV and x-ray reflection is reviewed. The main functions of mirrors in synchrotron beamlines are stated briefly and include deflection, filtration, power absorption, formation of a real image of the source, focusing, and collimation. Methods of fabrication of optical surfaces are described. Types of imperfections are discussed, including, aberrations, surface figure inaccuracy, roughness, and degradation due to use. Calculation of the photon beam thermal load, including computer modelling, is considered. 50 refs., 7 figs. (LEW)

  1. Manufacturability of compact synchrotron mirrors

    NASA Astrophysics Data System (ADS)

    Douglas, Gary M.

    1997-11-01

    While many of the government funded research communities over the years have put their faith and money into increasingly larger synchrotrons, such as Spring8 in Japan, and the APS in the United States, a viable market appears to exist for smaller scale, research and commercial grade, compact synchrotrons. These smaller, and less expensive machines, provide the research and industrial communities with synchrotron radiation beamline access at a portion of the cost of their larger and more powerful counterparts. A compact synchrotron, such as the Aurora-2D, designed and built by Sumitomo Heavy Industries, Ltd. of japan (SHI), is a small footprint synchrotron capable of sustaining 20 beamlines. Coupled with a Microtron injector, with 150 MeV of injection energy, an entire facility fits within a 27 meter [88.5 ft] square floorplan. The system, controlled by 2 personal computers, is capable of producing 700 MeV electron energy and 300 mA stored current. Recently, an Aurora-2D synchrotron was purchased from SHI by the University of Hiroshima. The Rocketdyne Albuquerque Operations Beamline Optics Group was approached by SHI with a request to supply a group of 16 beamline mirrors for this machine. These mirrors were sufficient to supply 3 beamlines for the Hiroshima machine. This paper will address engineering issues which arose during the design and manufacturing of these mirrors.

  2. Chinese "Magic" Mirrors.

    ERIC Educational Resources Information Center

    Swinson, Derek B.

    1992-01-01

    Chinese "magic" mirrors are made from bronze with the front side a mirror and the reverse side a molded image. When light is reflected from the mirror,the image on the reverse side appears. Discusses reflections of conventional mirrors, possible explanations for the magic mirror phenomenon, and applications of the phenomenon to…

  3. Double arch mirror study

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    The development of a method of mounting light weight glass mirrors for astronomical telescopes compatible with the goals of the Shuttle Infrared Telescope Facility (SIRTF) was investigated. A 20 in. diameter double arch lightweight mirror previously fabricated was modified to use a new mount configuration. This mount concept was developed and fabricated. The mounting concept of the double mounting mirror is outlined. The modifications made to the mirror, fabrication of the mirror mount, and room temperature testing of the mirror and mount and the extension of the mirror and mount concept to a full size (40 in. diameter) primary mirror for SIRTF are discussed.

  4. SXI prototype mirror mount

    NASA Astrophysics Data System (ADS)

    1995-04-01

    The purpose of this contract was to provide optomechanical engineering and fabrication support to the Solar X-ray Imager (SXI) program in the areas of mirror, optical bench and camera assemblies of the telescope. The Center for Applied Optics (CAO) worked closely with the Optics and S&E technical staff of MSFC to develop and investigate the most viable and economical options for the design and fabrication of a number of parts for the various telescope assemblies. All the tasks under this delivery order have been successfully completed within budget and schedule. A number of development hardware parts have been designed and fabricated jointly by MSFC and UAH for the engineering model of SXI. The major parts include a nickel electroformed mirror and a mirror mount, plating and coating of the ceramic spacers, and gold plating of the contact rings and fingers for the camera assembly. An aluminum model of the high accuracy sun sensor (HASS) was also designed and fabricated. A number of fiber optic tapers for the camera assembly were also coated with indium tin oxide and phosphor for testing and evaluation by MSFC. A large number of the SXI optical bench parts were also redesigned and simplified for a prototype telescope. These parts include the forward and rear support flanges, front aperture plate, the graphite epoxy optical bench and a test fixture for the prototype telescope. More than fifty (50) drawings were generated for various components of the prototype telescope. Some of these parts were subsequently fabricated at UAH machine shop or at MSFC or by the outside contractors. UAH also provide technical support to MSFC staff for a number of preliminary and critical design reviews. These design reviews included PDR and CDR for the mirror assembly by United Technologies Optical Systems (UTOS), and the program quarterly reviews, and SXI PDR and CDR. UAH staff also regularly attended the monthly status reviews, and made a significant number of suggestions to improve

  5. SXI prototype mirror mount

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The purpose of this contract was to provide optomechanical engineering and fabrication support to the Solar X-ray Imager (SXI) program in the areas of mirror, optical bench and camera assemblies of the telescope. The Center for Applied Optics (CAO) worked closely with the Optics and S&E technical staff of MSFC to develop and investigate the most viable and economical options for the design and fabrication of a number of parts for the various telescope assemblies. All the tasks under this delivery order have been successfully completed within budget and schedule. A number of development hardware parts have been designed and fabricated jointly by MSFC and UAH for the engineering model of SXI. The major parts include a nickel electroformed mirror and a mirror mount, plating and coating of the ceramic spacers, and gold plating of the contact rings and fingers for the camera assembly. An aluminum model of the high accuracy sun sensor (HASS) was also designed and fabricated. A number of fiber optic tapers for the camera assembly were also coated with indium tin oxide and phosphor for testing and evaluation by MSFC. A large number of the SXI optical bench parts were also redesigned and simplified for a prototype telescope. These parts include the forward and rear support flanges, front aperture plate, the graphite epoxy optical bench and a test fixture for the prototype telescope. More than fifty (50) drawings were generated for various components of the prototype telescope. Some of these parts were subsequently fabricated at UAH machine shop or at MSFC or by the outside contractors. UAH also provide technical support to MSFC staff for a number of preliminary and critical design reviews. These design reviews included PDR and CDR for the mirror assembly by United Technologies Optical Systems (UTOS), and the program quarterly reviews, and SXI PDR and CDR. UAH staff also regularly attended the monthly status reviews, and made a significant number of suggestions to improve

  6. Mirror Neurons and Mirror-Touch Synesthesia.

    PubMed

    Linkovski, Omer; Katzin, Naama; Salti, Moti

    2016-05-30

    Since mirror neurons were introduced to the neuroscientific community more than 20 years ago, they have become an elegant and intuitive account for different cognitive mechanisms (e.g., empathy, goal understanding) and conditions (e.g., autism spectrum disorders). Recently, mirror neurons were suggested to be the mechanism underlying a specific type of synesthesia. Mirror-touch synesthesia is a phenomenon in which individuals experience somatosensory sensations when seeing someone else being touched. Appealing as it is, careful delineation is required when applying this mechanism. Using the mirror-touch synesthesia case, we put forward theoretical and methodological issues that should be addressed before relying on the mirror-neurons account.

  7. Integral Flexure Mounts for Metal Mirrors for Cryogenic Use

    NASA Technical Reports Server (NTRS)

    Zewari, S. Wahid; Hylan, Jason E.; Irish, Sandra M.; Ohl, Raymond G.; Conkey, Shelly B.

    2006-01-01

    Semi-kinematic, six-degree-of-freedom flexure mounts have been incorporated as integral parts of metal mirrors designed to be used under cryogenic conditions as parts of an astronomical instrument. The design of the mirrors and their integral flexure mounts can also be adapted to other instruments and other operating temperatures. In comparison with prior kinematic cryogenic mirror mounts, the present mounts are more compact and can be fabricated easily using Ram-EDM (electrical discharge machining) process

  8. Solar simulator mirror refurbishment

    NASA Technical Reports Server (NTRS)

    Leverton, W. R.

    1974-01-01

    Solar simulator mirrors were refurbished. Two different refurbishment methods were employed. In the first, the electroformed mirror replica was removed from the casting and replaced with a new mirror replica. In the second, only the aluminized surface, with its protective overcoat, was removed from the mirror and replaced after cleaning of the nickel surface.

  9. Titanium Alloy Strong Back for IXO Mirror Segments

    NASA Technical Reports Server (NTRS)

    Byron, Glenn P.; Kai-Wang, Chan

    2011-01-01

    A titanium-alloy mirror-holding fixture called a strong back allows the temporary and permanent bonding of a 50 degree D263 glass x-ray mirror (IXO here stands for International X-ray Observatory). The strong back is used to hold and position a mirror segment so that mounting tabs may be bonded to the mirror with ultra-low distortion of the optical surface. Ti-15%Mo alloy was the material of choice for the strong back and tabs because the coefficient of thermal expansion closely matches that of the D263 glass and the material is relatively easy to machine. This invention has the ability to transfer bonded mounting points from a temporary location on the strong back to a permanent location on the strong back with minimal distortion. Secondly, it converts a single mirror segment into a rigid body with an acceptable amount of distortion of the mirror, and then maneuvers that rigid body into optical alignment such that the mirror segment can be bonded into a housing simulator or mirror module. Key problems are that the mirrors are 0.4-mm thick and have a very low coefficient of thermal expansion (CTE). Because the mirrors are so thin, they are very flexible and are easily distorted. When permanently bonding the mirror, the goal is to achieve a less than 1-micron distortion. Temperature deviations in the lab, which have been measured to be around 1 C, have caused significant distortions in the mirror segment.

  10. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, Thomas C.

    1995-01-01

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis.

  11. Kinematic high bandwidth mirror mount

    DOEpatents

    Kuklo, T.C.

    1995-03-21

    An adjustable mirror mount system for a mirror is disclosed comprising a mirror support having a planar surface thereon, a mirror frame containing a mirror and having a planar surface behind the mirror facing the planar surface of the mirror support and parallel to the reflecting surface of the mirror and mounted pivotally to the mirror support at a point central to the frame, a first adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along one axis lying in the plane of the planar surface of the mirror frame; and a second adjustment means between the mirror support and the mirror frame spaced from the central pivot mount for adjusting the movement of the mirror along a second axis lying in the plane of the planar surface of the mirror frame and perpendicular to the first axis. 7 figures.

  12. Cost-effective lightweight mirrors for aerospace and defense

    NASA Astrophysics Data System (ADS)

    Woodard, Kenneth S.; Comstock, Lovell E.; Wamboldt, Leonard; Roy, Brian P.

    2015-05-01

    The demand for high performance, lightweight mirrors was historically driven by aerospace and defense (A&D) but now we are also seeing similar requirements for commercial applications. These applications range from aerospace-like platforms such as small unmanned aircraft for agricultural, mineral and pollutant aerial mapping to an eye tracking gimbaled mirror for optometry offices. While aerospace and defense businesses can often justify the high cost of exotic, low density materials, commercial products rarely can. Also, to obtain high performance with low overall optical system weight, aspheric surfaces are often prescribed. This may drive the manufacturing process to diamond machining thus requiring the reflective side of the mirror to be a diamond machinable material. This paper summarizes the diamond machined finishing and coating of some high performance, lightweight designs using non-exotic substrates to achieve cost effective mirrors. The results indicate that these processes can meet typical aerospace and defense requirements but may also be competitive in some commercial applications.

  13. Tandem mirrors for neutron production

    SciTech Connect

    Doggett, J.N.

    1983-03-31

    Two mirror machine concepts are being studied as early-time, low-cost, neutron-producing devices for testing and demonstrating reactor-relevant fusion technology. The first of these concepts is for a new, small, driven, steady-state, D-T reactor, called the Technology Demonstration Facility (TDF). The second concept is for upgrades to the MFTF-B machine that burn tritium and run for pulse lengths of some hours. Both devices operate in the Kelley mode in order to provide high-wall loadings of 14-MeV neutrons, thereby providing a valuable test bed for reactor-relevant hardware and subsystems. Either one of these devices could be running in the early 1990's with first wall fluxes between 1.4 and 2.0 MW m/sup -2/.

  14. Lightweight Mirror Developments

    NASA Astrophysics Data System (ADS)

    Genet, Russell; Aurigema, Andrew; Badger, Steve; Bartels, Mel; Brodhacker, K. Lisa; Canestrari, Rodolfo; Chen, Peter; Connelley, Mike; Davis, David; Ghigo, Mauro; Jones, Greg; Liu, Tong; Mendex, Eric; Pareschi, Giovanni; Richardson, Terry; Rowe, David; Schmidt, Josh; Shah, Kiran; Villasenor, Efrain

    2009-05-01

    One goal of the Alt-Az Initiative is the development of transportable 1.5 meter class research telescopes. To this end, several Initiative members are developing lightweight, low cost, primary mirrors. Both multiple and single mirror telescope configurations are being considered. Thin meniscus mirrors are being slumped, and approaches for actively correcting these thin mirrors are being investigated. Sandwich mirrors with glass spacers and others with Foamglas cores are under development. Nanocomposite, polyurethane, and glass replica mirrors, which do not require optical grinding or figuring during production, are being evaluated. Finally, spin-cast polymer mirrors are being explored. Although several of these mirror developments are still very experimental, and some may only be useful in optically undemanding applications such as on-axis aperture near IR photometry or low resolution spectroscopy, it is our hope that these efforts will enable the development of transportable, low cost, lightweight, 1.5 meter class telescopes.

  15. Lightweight Zerodur Mirror Technology

    DTIC Science & Technology

    1982-10-01

    17 September 1981 Contract Expiration Date: 15 May 1982 Short Title of Work: Lightweight Zerodur Mirror Technology Program Code Number: 1LIO Period of...iepRA LIGHTWEIGHT ZERODUR MIRROR TECHNOLOGY 21 Sep 81 - 21 May 82 1. PERFORMING 0,10. REPORT NUMWERn 15512 7: AUTHOR(*J S. CONTRACT OR GRANT NUMSER[JlII...1S. KIEV WORDS (Continue on reverse aide If necesery 1nd Identify b? block nwi nhm ) Zerodur Lightweight Mirrors Mirror Blank Fabrication Frit

  16. Durable solar mirror films

    DOEpatents

    O'Neill, Mark B.; Henderson, Andrew J.; Hebrink, Timothy J.; Katare, Rajesh K.; Jing, Naiyong; North, Diane; Peterson, Eric M.

    2017-02-14

    The present disclosure generally relates to durable solar mirror films, methods of making durable solar mirror films, and constructions including durable solar mirror films. In one embodiment, the present disclosure relates to a solar mirror film comprising: a multilayer optical film layer including having a coefficient of hygroscopic expansion of less than about 30 ppm per percent relative humidity; and a reflective layer having a coefficient of hygroscopic expansion.

  17. Anastigmatic three-mirror telescope

    NASA Technical Reports Server (NTRS)

    Korsch, D. G. (Inventor)

    1978-01-01

    A three-mirror telescope for extraterrestrial observations is described. An ellipsoidal primary mirror, a hyperbolic secondary mirror, and an ellipsoidal tertiary mirror, produce an image in a conveniently located finite plane for viewing.

  18. Enabling advanced mirror blank design through modern optical fabrication technology

    NASA Astrophysics Data System (ADS)

    Wilson, Timothy J.; Genberg, Victor L.

    1994-02-01

    Mirror blanks used in high-reliability optical systems for airborne and spaceborne applications have many requirements in terms of weight, stiffness and moment of inertia, as well as mounting and gravitational influences. Lightweight and ultra-lightweight mirror blank design techniques have been enhanced by recent technological developments in mirror blank fabrication and optical figuring. This paper briefly reviews traditional mirror blank design considerations in light of new fabrication technologies such as abrasive water jet machining of mirror cores and ion figuring of optical surfaces. The impact of these new technologies on mirror blank design is also discussed, as well as new design and analytical techniques using NASTRAN. Actual production data using these techniques are presented.

  19. Water Cooled Mirror Design

    SciTech Connect

    Dale, Gregory E.; Holloway, Michael Andrew; Pulliam, Elias Noel

    2015-03-30

    This design is intended to replace the current mirror setup being used for the NorthStar Moly 99 project in order to monitor the target coupon. The existing setup has limited movement for camera alignment and is difficult to align properly. This proposed conceptual design for a water cooled mirror will allow for greater thermal transfer between the mirror and the water block. It will also improve positioning of the mirror by using flexible vacuum hosing and a ball head joint capable of a wide range of motion. Incorporating this design into the target monitoring system will provide more efficient cooling of the mirror which will improve the amount of diffraction caused by the heating of the mirror. The process of aligning the mirror for accurate position will be greatly improved by increasing the range of motion by offering six degrees of freedom.

  20. Development of Table-Top mirror trap for flute stabilization research

    NASA Astrophysics Data System (ADS)

    Seemann, Omri; Be'Ery, Ilan

    2015-11-01

    Mirror traps might be viable candidates for fusion machines. These machines are technically and physically simple but suffer from the Rayleigh-Taylor-like flute instability. A new table top mirror machine was built in order to research ways to mitigate this instability. One possible solution for this problem which was researched in the past is using oscillatory fields. A description of the system and diagnostics, preliminary results and a review of the main mechanisms with which stabilization might occur are presented.

  1. Optical fabrication of lightweighted 3D printed mirrors

    NASA Astrophysics Data System (ADS)

    Herzog, Harrison; Segal, Jacob; Smith, Jeremy; Bates, Richard; Calis, Jacob; De La Torre, Alyssa; Kim, Dae Wook; Mici, Joni; Mireles, Jorge; Stubbs, David M.; Wicker, Ryan

    2015-09-01

    Direct Metal Laser Sintering (DMLS) and Electron Beam Melting (EBM) 3D printing technologies were utilized to create lightweight, optical grade mirrors out of AlSi10Mg aluminum and Ti6Al4V titanium alloys at the University of Arizona in Tucson. The mirror prototypes were polished to meet the λ/20 RMS and λ/4 P-V surface figure requirements. The intent of this project was to design topologically optimized mirrors that had a high specific stiffness and low surface displacement. Two models were designed using Altair Inspire software, and the mirrors had to endure the polishing process with the necessary stiffness to eliminate print-through. Mitigating porosity of the 3D printed mirror blanks was a challenge in the face of reconciling new printing technologies with traditional optical polishing methods. The prototypes underwent Hot Isostatic Press (HIP) and heat treatment to improve density, eliminate porosity, and relieve internal stresses. Metal 3D printing allows for nearly unlimited topological constraints on design and virtually eliminates the need for a machine shop when creating an optical quality mirror. This research can lead to an increase in mirror mounting support complexity in the manufacturing of lightweight mirrors and improve overall process efficiency. The project aspired to have many future applications of light weighted 3D printed mirrors, such as spaceflight. This paper covers the design/fab/polish/test of 3D printed mirrors, thermal/structural finite element analysis, and results.

  2. LOXT mirror design study

    NASA Technical Reports Server (NTRS)

    Vanspeybroeck, L.; Antrim, W.; Boyd, D.; Giacconi, R.; Sinnamon, G.; Stille, F.

    1972-01-01

    The final report for the large orbiting X-ray telescope (LOXT) high resolution mirror design study is presented. The following tasks were performed: (1) Generation of a reference and alternate preliminary design for the LOXT high resolution mirror assembly, which will meet the LOXT scientific requirements, and are within the present state of the art of materials and fabrication techniques. (2) Measurement, in X-rays, of the scattering properties of a variety of optical flats, embodying materials, coatings, and polishing techniques which might be applicable to the flight configuration LOXT high resolution mirror. (3) Preparation of a procurement specification for a paraboloid test mirror of the size of the innermost paraboloid of the high resolution mirror assembly, including the design requirements for the reference design evolved from this preliminary design study. The results of the engineering and scientific analysis and the conclusions drawn are presented. The procurement specification for the test mirror is included.

  3. Erected mirror optical switch

    DOEpatents

    Allen, James J.

    2005-06-07

    A microelectromechanical (MEM) optical switching apparatus is disclosed that is based on an erectable mirror which is formed on a rotatable stage using surface micromachining. An electrostatic actuator is also formed on the substrate to rotate the stage and mirror with a high angular precision. The mirror can be erected manually after fabrication of the device and used to redirect an incident light beam at an arbitrary angel and to maintain this state in the absence of any applied electrical power. A 1.times.N optical switch can be formed using a single rotatable mirror. In some embodiments of the present invention, a plurality of rotatable mirrors can be configured so that the stages and mirrors rotate in unison when driven by a single micromotor thereby forming a 2.times.2 optical switch which can be used to switch a pair of incident light beams, or as a building block to form a higher-order optical switch.

  4. Laser correcting mirror

    DOEpatents

    Sawicki, Richard H.

    1994-01-01

    An improved laser correction mirror (10) for correcting aberrations in a laser beam wavefront having a rectangular mirror body (12) with a plurality of legs (14, 16, 18, 20, 22, 24, 26, 28) arranged into opposing pairs (34, 36, 38, 40) along the long sides (30, 32) of the mirror body (12). Vector force pairs (49, 50, 52, 54) are applied by adjustment mechanisms (42, 44, 46, 48) between members of the opposing pairs (34, 36, 38, 40) for bending a reflective surface 13 of the mirror body 12 into a shape defining a function which can be used to correct for comatic aberrations.

  5. Cost effective aluminum beryllium mirrors for critical optics applications

    NASA Astrophysics Data System (ADS)

    Say, Carissa; Duich, Jack; Huskamp, Chris; White, Ray

    2013-09-01

    The unique performance of aluminum-beryllium frequently makes it an ideal material for manufacturing precision optical-grade metal mirrors. Traditional methods of manufacture utilize hot-pressed powder block in billet form which is subsequently machined to final dimensions. Complex component geometries such as lightweighted, non-plano mirrors require extensive tool path programming, fixturing, and CNC machining time and result in a high buy-to-fly ratio (the ratio of the mass of raw material purchased to the mass of the finished part). This increases the cost of the mirror structure as a significant percentage of the procurement cost is consumed in the form of machining, tooling, and scrap material that do not add value to the final part. Inrad Optics, Inc. and IBC Advanced Alloys Corp. undertook a joint study to evaluate the suitability of investment-cast Beralcast® 191 and 363 aluminum-beryllium as a precision mirror substrate material. Net shape investment castings of the desired geometry minimizes machining to just cleanup stock, thereby reducing the recurring procurement cost while still maintaining performance. The thermal stability of two mirrors, (one each of Beralcast® 191 and Beralcast® 363), was characterized from -40°F to +150°F. A representative pocketed mirror was developed, including the creation of a relevant geometry and production of a cast component to validate the approach. Information from the demonstration unit was used as a basis for a comparative cost study of the representative mirror produced in Beralcast® and one machined from a billet of AlBeMet® 162 (AlBeMet® is a registered trademark of Materion Corporation). The technical and financial results of these studies will be discussed in detail.

  6. Fabrication of large aperture SiC brazing mirror

    NASA Astrophysics Data System (ADS)

    Li, Ang; Wang, Peipei; Dong, Huiwen; Wang, Peng

    2016-10-01

    The SiC brazing mirror is the mirror whose blank is made by assembling together smaller SiC pieces with brazing technique. Using such kinds of joining techniques, people can manufacture large and complex SiC assemblies. The key technologies of fabricating and testing SiC brazing flat mirror especially for large aperture were studied. The SiC brazing flat mirror was ground by smart ultrasonic-milling machine, and then it was lapped by the lapping smart robot and measured by Coordinate Measuring Machine (CMM). After the PV of the surface below 4um, we did classic coarse polishing to the surface and studied the shape of the polishing tool which directly effects removal amount distribution. Finally, it was figured by the polishing smart robot and measured by Fizeau interferometer. We also studied the influence of machining path and removal functions of smart robots on the manufacturing results and discussed the use of abrasive in this process. At last, an example for fabricating and measuring a similar SiC brazing flat mirror with the aperture of 600 mm made by Shanghai Institute of Ceramics was given. The mirror blank consists of 6 SiC sectors and the surface was finally processed to a result of the Peak-to-Valley (PV) 150nm and Root Mean Square (RMS) 12nm.

  7. Primary mirror assemblies for large space telescopes

    NASA Astrophysics Data System (ADS)

    Malamed, Evgeny R.; Sokolsky, M. N.

    1995-09-01

    In this report are considered the basic problems which relate to developemnt, manufacture, experimental trying out, and usage of primary mirrors (PM) of the large space telescopes intended to perform distant sounding of the Earth. Attention is concentrated on development of weight-reduced passive mirrors which ensure more reliable operation of the telescope as a whole. In the report we expressed the opinion that it is quite possible to manufacture a passive weight-reduced PM if its diameter is equal approximately to 3 m. Materials which may be used for the manufacturing of PM are beryllium and silicon carbide, physical and mechanical parameters of which are the most preferable ones. But it should be taken into consideration that this is the glass ceramic of CO115M brand which has been mastered by the industry of Russia in the greatest extent. It was confirmed that parameters of this material remain unchanged during a long period of time. Constructions of the PM, made of glass ceramic, as well as constructions of holders intended to fix the mirror, are presented in this report. A holder is used first of all to prevent lowering of a PM surface quality after a mirror has been removed from a machine and fixed in a primary mirror assembly (PMA). At present two-layer construction of a PM is preferable. This construction consists of thick base including weight reduction structure, which is in a radius which is optimum from the standpoint of deformation of a mirror operating surface. In the process of manufacture a mirror is deprived of its weight with the use of special pneumatic off-loading elements. PMA is erected in vertical plane by means of using an interferometric inspection system. In the end of this report we expressed the views on an approach to engineering of a PM by taking into account potentialities both of space ships and of carrier rockets.

  8. Splayed mirror light pipes

    SciTech Connect

    Swift, P.D.

    2010-02-15

    An expression is given for the transmission of the rectangular-section mirror light pipe. The expression is used to model throughputs for simulated solar conditions over a calender year. It is found that the splaying of a mirror light pipe results in a significant increase in throughputs particularly in winter months. (author)

  9. Corticospinal mirror neurons.

    PubMed

    Kraskov, A; Philipp, R; Waldert, S; Vigneswaran, G; Quallo, M M; Lemon, R N

    2014-01-01

    Here, we report the properties of neurons with mirror-like characteristics that were identified as pyramidal tract neurons (PTNs) and recorded in the ventral premotor cortex (area F5) and primary motor cortex (M1) of three macaque monkeys. We analysed the neurons' discharge while the monkeys performed active grasp of either food or an object, and also while they observed an experimenter carrying out a similar range of grasps. A considerable proportion of tested PTNs showed clear mirror-like properties (52% F5 and 58% M1). Some PTNs exhibited 'classical' mirror neuron properties, increasing activity for both execution and observation, while others decreased their discharge during observation ('suppression mirror-neurons'). These experiments not only demonstrate the existence of PTNs as mirror neurons in M1, but also reveal some interesting differences between M1 and F5 mirror PTNs. Although observation-related changes in the discharge of PTNs must reach the spinal cord and will include some direct projections to motoneurons supplying grasping muscles, there was no EMG activity in these muscles during action observation. We suggest that the mirror neuron system is involved in the withholding of unwanted movement during action observation. Mirror neurons are differentially recruited in the behaviour that switches rapidly between making your own movements and observing those of others.

  10. Stable mirror mount

    DOEpatents

    Cutburth, Ronald W.

    1990-01-01

    An improved mirror mount assembly is disclosed. The mirror mount assembly provides a post assembly slidable in a Y-axis orientation and a nut plate assembly slidable in an X-axis orientation and a device for simultaneously locking the post assembly and the key assembly in a fixed position.

  11. Stable mirror mount

    DOEpatents

    Cutburth, R.W.

    1983-11-04

    An improved mirror mount assembly is disclosed. The mirror mount assembly provides a post assembly slidable in a Y-axis orientation and a nut plate assembly slidable in an X-axis orientation and means for simultaneously locking said post assembly and said key assembly in a fixed position.

  12. Bronze rainbow hologram mirrors

    NASA Astrophysics Data System (ADS)

    Dawson, P.

    2006-02-01

    This project draws on holographic embossing techniques, ancient artistic conventions of bronze mirror design and modelling and casting processes to accomplish portraiture of reflection. Laser scanning, 3D computer graphics and holographic imaging are employed to enable a permanent 3D static holographic image to appear integrated with the real-time moving reflection of a viewer's face in a polished bronze disc. The disc and the figure which holds it (caryatid) are cast in bronze from a lost wax model, a technique which has been used for millennia to make personal mirrors. The Caryatid form of bronze mirror which went through many permutations in ancient Egyptian, Greece and Rome shows a plethora of expressive figure poses ranging from sleek nudes to highly embellished multifigure arrangements. The prototype of this series was made for Australian choreographer Graeme Murphy, Artistic Director of the Sydney Dance Company. Each subsequent mirror will be unique in figure and holographic imagery as arranged between artist and subject. Conceptually this project references both the modern experience of viewing mirrors retrieved from ancient tombs, which due to deterioration of the surface no longer reflect, and the functioning of Chinese Magic mirrors, which have the ability to project a predetermined image. Inspired by the metaphorical potential of these mirrors, which do not reflect the immediate reality of the viewer, this bronze hologram mirror series enables each viewer to reflect upon himself or herself observing simultaneously the holographic image and their own partially obliterated reflection.

  13. Lightweight optical mirrors formed in single crystal substrate

    NASA Technical Reports Server (NTRS)

    Bly, Vincent T. (Inventor)

    2006-01-01

    This invention is directed to a process for manufacturing a lightweight mirror from a single crystal material, such as single crystal silicon. As a near perfect single crystal material, single crystal silicon has much lower internal stress than a conventional material. This means much less distortion of the optical surface during the light weighting process. After being ground and polished, a single crystal silicon mirror is light weighted by removing material from the back side using ultrasonic machining. After the light weighting process, the single crystal silicon mirror may be used as-is or further figured by conventional polishing or ion milling, depending on the application and the operating wavelength.

  14. Tandem mirror plasma confinement apparatus

    DOEpatents

    Fowler, T. Kenneth

    1978-11-14

    Apparatus and method for confining a plasma in a center mirror cell by use of two end mirror cells as positively charged end stoppers to minimize leakage of positive particles from the ends of the center mirror cell.

  15. Mirror writing and handedness.

    PubMed

    Tucha, O; Aschenbrenner, S; Lange, K W

    2000-07-01

    It has been reported that left-handed subjects are better able to write in mirror-reversed script than right-handers (Tankle & Heilman, 1983). Vaid and Stiles Davis (1989) conducted studies which led them to contradict the supposed superiority of left-handers in this area. In these studies, left as well as right-handed subjects were examined under normal- and mirror-writing conditions. Both examinations included the analysis of writing time and the accuracy of mirror writing (error rates). Using a digitizing tablet, we examined normal- and mirror-writing performance of left-handers, right-handers, and left-handed subjects who habitually write with their right hand. Our results support the finding of Tankle and Heilman (1983) that left-handers perform better in mirror-writing tasks.

  16. Partially segmented deformable mirror

    DOEpatents

    Bliss, Erlan S.; Smith, James R.; Salmon, J. Thaddeus; Monjes, Julio A.

    1991-01-01

    A partially segmented deformable mirror is formed with a mirror plate having a smooth and continuous front surface and a plurality of actuators to its back surface. The back surface is divided into triangular areas which are mutually separated by grooves. The grooves are deep enough to make the plate deformable and the actuators for displacing the mirror plate in the direction normal to its surface are inserted in the grooves at the vertices of the triangular areas. Each actuator includes a transducer supported by a receptacle with outer shells having outer surfaces. The vertices have inner walls which are approximately perpendicular to the mirror surface and make planar contacts with the outer surfaces of the outer shells. The adhesive which is used on these contact surfaces tends to contract when it dries but the outer shells can bend and serve to minimize the tendency of the mirror to warp.

  17. Partially segmented deformable mirror

    DOEpatents

    Bliss, E.S.; Smith, J.R.; Salmon, J.T.; Monjes, J.A.

    1991-05-21

    A partially segmented deformable mirror is formed with a mirror plate having a smooth and continuous front surface and a plurality of actuators to its back surface. The back surface is divided into triangular areas which are mutually separated by grooves. The grooves are deep enough to make the plate deformable and the actuators for displacing the mirror plate in the direction normal to its surface are inserted in the grooves at the vertices of the triangular areas. Each actuator includes a transducer supported by a receptacle with outer shells having outer surfaces. The vertices have inner walls which are approximately perpendicular to the mirror surface and make planar contacts with the outer surfaces of the outer shells. The adhesive which is used on these contact surfaces tends to contract when it dries but the outer shells can bend and serve to minimize the tendency of the mirror to warp. 5 figures.

  18. Optimum selection of high performance mirror substrates for diamond finishing

    NASA Astrophysics Data System (ADS)

    Woodard, Kenneth S.; Comstock, Lovell E.; Wamboldt, Leonard; Sutherland, James S.

    2016-05-01

    Due to advances in manufacturing processes, the substrate options for high performance diamond machined mirrors are expanding. Fewer compromises have to be made to achieve the needed weight, stiffness and finish while maintaining reasonable costs. In addition to the traditional mirror materials like aluminum and beryllium, there are some less common materials that can now be included in the trade space that fill the cost and performance continuum between wrought aluminum and beryllium mirrors. Aluminum and beryllium, respectively, had been the low cost/fair performance and very high cost/very high performance bounds for substrate selection. These additional substrates provide multiple near net shape blank options and processes, mostly within these bounds, that can be considered in a mirror cost versus performance trade analysis. This paper will include a summary of some advances in manufacturing processes that provide more substrate options for diamond machined mirrors with some sample performance analysis and data. This is merged with the traditional substrate options to illustrate the now larger mirror substrate trade space. Some benchmark structural analysis is provided to back up a generic mirror design trade study.

  19. Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). This device would operate at much higher plasma densities and with much larger LD ratios than previous mirror machines. Several advantages accrue from such a design. First, the high LA:) ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. Second, the high plasma density will result in the plasma behaving much more Re a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. An experimental GDM device is currently being constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. Initial experiments are expected to commence in the late fall of 2000.

  20. Coarse alignment of thin-shell, segmented mirrors for Wolter-I telescopes

    NASA Astrophysics Data System (ADS)

    Donovan, Benjamin D.; Hertz, Edward; Marquez, Vanessa; McMuldroch, Stuart; Reid, Paul B.; Allured, Ryan

    2015-09-01

    The alignment of thin-shell, segmented mirrors for Wolter-I telescopes frequently involves the use of a Hartmann test. In order to get optical throughput in the Hartmann test, the mirrors must first be coarsely aligned to one another and to the metrology system. In the past, the coarse alignment of these mirrors at the Smithsonian Astrophysical Observatory has largely relied upon component machine tolerances and contact measurements with a coordinate measurement machine (CMM). This process takes time and does not produce reliable nor repeatable results. Thus, methods were developed to allow for the quick and reliable coarse alignment of thin- shell, segmented mirrors at their final locations in the mirror assembly. We present the coarse alignment system developed at the Smithsonian Astrophysical Observatory and its use in the alignment of thin-shell, segmented mirrors for the adjustable X-ray optics program.

  1. Nanolaminate deformable mirrors

    DOEpatents

    Papavasiliou, Alexandros P.; Olivier, Scot S.

    2009-04-14

    A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

  2. Nanolaminate deformable mirrors

    DOEpatents

    Papavasiliou, Alexandros P.; Olivier, Scot S.

    2010-04-06

    A deformable mirror formed out of two layers of a nanolaminate foil attached to a stiff substrate is introduced. Deformation is provided by an electrostatic force between two of the layers. The internal stiffness of the structure allows for high-spatial-frequency shapes. The nanolaminate foil of the present invention allows for a high-quality mirror surface. The device achieves high precision in the vertical direction by using foils with accurately controlled thicknesses, but does not require high precision in the lateral dimensions, allowing such mirrors to be fabricated using crude lithography techniques. Such techniques allow structures up to about the meter scale to be fabricated.

  3. Large hybrid membrane mirrors

    NASA Astrophysics Data System (ADS)

    Sohn, Erika; Ruiz Schneider, Elfego; Ferreira, Alejandra

    2003-01-01

    The trend to minimize the thickness in optical mirrors has led to several practical limits in their fabrication and operation. The design of a flexible membrane mirror segment, which overcomes most of these limitations and can be conformed to giant segmented primary mirrors, is presented. The segment consists of a lightweight multi-layer hybrid structure, which will permit precise active control of the reflecting surface by means of a continuous elastic medium interface with embedded pneumatic actuators. Conceptual designs, finite element analysis model simulations and experimental results are included.

  4. NIF small mirror mount

    SciTech Connect

    McCarville, T

    1999-07-01

    A number of small mirror mounts have been identified that meet the stringent stability, wave front, and cleanliness standards of the NIF. These requirements are similar to those required in other performance critical optical design applications. Future design teams would conserve time and effort if recognized standards were established for mirror mount design and performance characteristics. Standards for stability, physical features, wave front distortion, and cleanliness would simplify the qualification process considerably. At this point such standards are not difficult to define, as the technical support work has been performed repeatedly by mirror mount consumers and suppliers.

  5. Mirror plasma apparatus

    DOEpatents

    Moir, Ralph W.

    1981-01-01

    A mirror plasma apparatus which utilizes shielding by arc discharge to form a blanket plasma and lithium walls to reduce neutron damage to the wall of the apparatus. An embodiment involves a rotating liquid lithium blanket for a tandem mirror plasma apparatus wherein the first wall of the central mirror cell is made of liquid lithium which is spun with angular velocity great enough to keep the liquid lithium against the first material wall, a blanket plasma preventing the lithium vapor from contaminating the plasma.

  6. Lightweight mirror construction optimization

    NASA Astrophysics Data System (ADS)

    Mooney, J. T.; Allen, M. A.; Bolton, J.; Dahl, R. J.; Lintz, E. A.

    2015-10-01

    Large, lightweight mirrors are a critical component in space based imaging applications. These mirrors have traditionally required long manufacturing cycle times with associated high costs. In this paper, the key cost and schedule drivers for the production of large, lightweight mirrors will be reviewed along with enabling solutions that could provide significant cost and schedule reductions while maintaining the high quality performance required for these challenging applications. The technologies include advancements in replication, construction, and bonding. Initial feasibility tests and associated results will be presented.

  7. Machine Shop Grinding Machines.

    ERIC Educational Resources Information Center

    Dunn, James

    This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

  8. The Rotating Mirror.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1981-01-01

    Discusses theory of the rotating mirror, its use in measuring the velocity of the electrical signal in wires, and the velocity of light. Concludes with a description of the manometric flame apparatus developed for analyzing sound waves. (SK)

  9. JWST Mirror Installation

    NASA Video Gallery

    The first six of 18 hexagonal shaped segments that will form NASA’s James Webb Space Telescope’s primary mirror for space observations were readied this week to begin final cryogenic testing at...

  10. The Athena Mirror

    NASA Astrophysics Data System (ADS)

    Wille, Eric

    2016-07-01

    The Athena mission (Advanced Telescope for High Energy Astrophysics) requires lightweight X-ray Wolter optics with a high angular resolution and large effective area. For achieving an effective area of 2 m^2 (at 1 keV) and an angular resolution of below 5 arcsec, the Silicon Pore Optics technology was developed by ESA together with a consortium of European industry. Silicon Pore Optics are made of commercial Si wafers using process technology adapted from the semiconductor industry. We present the current design of the Athena mirror concentrating on the technology development status of the Silicon Pore Optics, ranging from the manufacturing of single mirror plates towards complete focusing mirror modules and their integration into the mirror structure.

  11. Mirror contamination in space I: mirror modelling

    NASA Astrophysics Data System (ADS)

    Krijger, J. M.; Snel, R.; van Harten, G.; Rietjens, J. H. H.; Aben, I.

    2014-10-01

    We present a comprehensive model that can be employed to describe and correct for degradation of (scan) mirrors and diffusers in satellite instruments that suffer from changing optical Ultraviolet to visible (UV-VIS) properties during their operational lifetime. As trend studies become more important, so does the importance of understanding and correcting for this degradation. This is the case not only with respect to the transmission of the optical components, but also with respect to wavelength, polarisation, or scan-angle effects. Our hypothesis is that mirrors in flight suffer from the deposition of a thin absorbing layer of contaminant, which slowly builds up over time. We describe this with the Mueller matrix formalism and Fresnel equations for thin multi-layer contamination films. Special care is taken to avoid the confusion often present in earlier publications concerning the Mueller matrix calculus with out-of-plane reflections. The method can be applied to any UV-VIS satellite instrument. We illustrate and verify our approach to the optical behaviour of the multiple scan mirrors of SCIAMACHY (onboard ENVISAT).

  12. Mirror Attachment For Borescope

    NASA Technical Reports Server (NTRS)

    Gearhart, John F.; Peloquin, James E.

    1994-01-01

    Attachment for articulated borescope provides views into small, normally inaccessible spaces. Simple small round mirror on extension arm welded to borescope head. Tilted at angle to axis of borescope head, mirror provides views sideways to borescope head. Disassembly of turbopump blades not necessary to enable fluorescent-penetrant-dye inspection. Attachment used to inspect difficult-to-reach internal parts of other assemblies. Also used for inspection with ordinary white light.

  13. Towards a better mirror

    NASA Technical Reports Server (NTRS)

    Hoffer, David

    1987-01-01

    Telesat's Getaway Special competition was designed to promote interest in space among high school students in Canada. The winning entry proposed the manufacture of mirrors in microgravity and to compare the optical properties of these mirrors with similar ones made on Earth. Telesat engineers designed and built the experiment which flew on the Atlantic shuttle on November 27, 1985. This paper outlines the design evolution, its implementation, the manufacture and test of the GAS and the results of the experiment.

  14. Extreme ultraviolet lithography machine

    DOEpatents

    Tichenor, Daniel A.; Kubiak, Glenn D.; Haney, Steven J.; Sweeney, Donald W.

    2000-01-01

    An extreme ultraviolet lithography (EUVL) machine or system for producing integrated circuit (IC) components, such as transistors, formed on a substrate. The EUVL machine utilizes a laser plasma point source directed via an optical arrangement onto a mask or reticle which is reflected by a multiple mirror system onto the substrate or target. The EUVL machine operates in the 10-14 nm wavelength soft x-ray photon. Basically the EUV machine includes an evacuated source chamber, an evacuated main or project chamber interconnected by a transport tube arrangement, wherein a laser beam is directed into a plasma generator which produces an illumination beam which is directed by optics from the source chamber through the connecting tube, into the projection chamber, and onto the reticle or mask, from which a patterned beam is reflected by optics in a projection optics (PO) box mounted in the main or projection chamber onto the substrate. In one embodiment of a EUVL machine, nine optical components are utilized, with four of the optical components located in the PO box. The main or projection chamber includes vibration isolators for the PO box and a vibration isolator mounting for the substrate, with the main or projection chamber being mounted on a support structure and being isolated.

  15. Superconducting mirror for laser gyroscope

    SciTech Connect

    Wang, X.

    1991-05-14

    This paper describes an apparatus for reflecting a light beam. It comprises: a mirror assembly comprising a substrate and a superconductive mirror formed on such substrate, wherein: the substrate is optically transparent to the light beam and has a thickness of from about 0.5 to about 1.0 millimeter, and the superconductive mirror has a thickness of from about 0.5 to about 1.0 microns; means for cooling the superconductive mirror; means for measuring the temperature of the superconductive mirror; means for determining the reflectivity of the superconductive mirror; and means for varying the reflectivity of the superconductive mirror.

  16. Afocal two-mirror system

    NASA Astrophysics Data System (ADS)

    Puryaev, Daniil T.

    1993-06-01

    With mirrors of any aperture, the afocal two-mirror system has no spherical aberration. One mirror is spherical, and the other mirror is always an aspherical surface that is equidistant to the virtual parabolic mirror, the focal length of the latter being equal to the air separation between the mirrors. Therefore, a possibility exists of inspecting the aspherical surface shape by means of the known testing methods of the parabolic mirror. The system under consideration has some important technological advantages in comparison with the well-known Mersen system.

  17. Treatments To Produce Stabilized Aluminum Mirrors for Cryogenic Uses

    NASA Technical Reports Server (NTRS)

    Zewari, Wahid; Barthelmy, Michael; Ohl, Raymond

    2005-01-01

    Five metallurgical treatments have been tested as means of stabilizing mirrors that are made of aluminum alloy 6061 and are intended for use in cryogenic applications. Aluminum alloy 6061 is favored as a mirror material by many scientists and engineers. Like other alloys, it shrinks upon cool-down from room temperature to cryogenic temperature. This shrinkage degrades the optical quality of the mirror surfaces. Hence, the metallurgical treatments were tested to determine which one could be most effective in minimizing the adverse optical effects of cooldown to cryogenic temperatures. Each of the five metallurgical treatments comprises a multistep process, the steps of which are interspersed with the steps of the mirror-fabrication process. The five metallurgical-treatment/fabrication.- process combinations were compared with each other and with a benchmark fabrication process, in which a mirror is made from an alloy blank by (1) symmetrical rough machining, (2) finish machining to within 0.006 in. (. 0.15 mm) of final dimensions, and finally (3) diamond turning to a mirror finish.

  18. SST dual-mirror telescope for Cherenkov Telescope Array: an innovative mirror manufacturing process

    NASA Astrophysics Data System (ADS)

    Dumas, Delphine; Huet, Jean-Michel; Dournaux, Jean-Laurent; Laporte, Philippe; Rulten, Cameron; Schmoll, Jurgen; Sol, Hélène; Sayède, Frédéric; Micolon, Patrice; Glicenstein, Jean-François; Peyaud, Bernard

    2014-07-01

    The Observatoire de Paris is constructing a prototype Small-Sized Telescope (SST) for the Cherenkov Telescope Array (CTA), named SST-GATE, based on the dual-mirror Schwarzschild-Couder optical design. Considering the mirrors size and its specific curvature and the optical requirements for the Cherenkov imaging telescope, a non-conventional process has been used for designing and manufacturing the mirrors of the SST-GATE prototype. Based on machining, polishing and coating of aluminium bulk samples, this process has been validated by simulation and tests that will be detailed in this paper after a discussion on the Schwarzschild-Couder optical design which so far has never been used to design ground based telescopes. Even if the SST-GATE is a prototype for small size telescopes of the CTA array, the primary mirror of the telescope is 4 meters diameter, and it has to be segmented. Due to the dual-mirror configuration, the alignment is a complex task that needs a well defined and precise process that will be discussed in this paper.

  19. Method for providing mirror surfaces with protective strippable polymeric film

    DOEpatents

    Edwards, Charlene C.; Day, Jack R.

    1980-01-01

    This invention is a method for forming a protective, strippable, elastomeric film on a highly reflective surface. The method is especially well suited for protecting diamond-machined metallic mirrors, which are susceptible not only to abrasion and mechanical damage but also to contamination and corrosion by various fluids. In a typical use of the invention, a diamond-machined copper mirror surface is coated uniformly with a solution comprising a completely polymerized and completely cured thermoplastic urethane elastomer dissolved in tetrahydrofuran. The applied coating is evaporated to dryness, forming a tough, adherent, impermeable, and transparent film which encapsulates dust and other particulates on the surface. The film may be left in place for many months. When desired, the film may be stripped intact, removing the entrapped particulates and leaving no residue on the mirror surface.

  20. Actuated Hybrid Mirror Telescope

    NASA Technical Reports Server (NTRS)

    Hickey, Gregory; Redding, David; Lowman, Andrew; Cohen, David; Ohara, Catherine

    2005-01-01

    The figure depicts the planned Actuated Hybrid Mirror Telescope (AHMT), which is intended to demonstrate a new approach to the design and construction of wide-aperture spaceborne telescopes for astronomy and Earth science. This technology is also appropriate for Earth-based telescopes. The new approach can be broadly summarized as using advanced lightweight mirrors that can be manufactured rapidly at relatively low cost. More specifically, it is planned to use precise replicated metallic nanolaminate mirrors to obtain the required high-quality optical finishes. Lightweight, dimensionally stable silicon carbide (SiC) structures will support the nanolaminate mirrors in the required surface figures. To enable diffraction- limited telescope performance, errors in surface figures will be corrected by use of mirror-shape-control actuators that will be energized, as needed, by a wave-front-sensing and control system. The concepts of nanolaminate materials and mirrors made from nanolaminate materials were discussed in several previous NASA Tech Briefs articles. Nanolaminates constitute a relatively new class of materials that can approach theoretical limits of stiffness and strength. Nanolaminate mirrors are synthesized by magnetron sputter deposition of metallic alloys and/or compounds on optically precise master surfaces to obtain optical-quality reflector surfaces backed by thin shell structures. As an integral part of the deposition process, a layer of gold that will constitute the reflective surface layer is deposited first, eliminating the need for a subsequent and separate reflective-coating process. The crystallographic textures of the nanolaminate will be controlled to optimize the performance of the mirror. The entire deposition process for making a nanolaminate mirror takes less than 100 hours, regardless of the mirror diameter. Each nanolaminate mirror will be bonded to its lightweight SiC supporting structure. The lightweight nanolaminate mirrors and Si

  1. Mechanical-engineering aspects of mirror-fusion technology

    SciTech Connect

    Fisher, D.K.; Doggett, J.N.

    1982-07-15

    The mirror approach to magnetic fusion has evolved from the original simple mirror cell to today's mainline effort: the tandem-mirror machine with thermal barriers. Physics and engineering research is being conducted throughout the world, with major efforts in Japan, the USSR, and the US. At least one facility under construction (MFTF-B) will approach equivalent energy breakeven in physics performance. Significant mechanical engineering development is needed, however, before a demonstration reactor can be constructed. The principal areas crucial to mirror reactor development include large high-field superconducting magnets, high-speed continuous vacuum-pumping systems, long-pulse high-power neutral-beam and rf-plasma heating systems, and efficient high-voltage high-power direct converters. Other areas common to all fusion systems include tritium handling technology, first-wall materials development, and fusion blanket design.

  2. Polarized Nuclei in a Simple Mirror Fusion Reactor

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    1995-01-01

    The possibility of enhancing the ratio of output to input power Q in a simple mirror machine by polarizing Deuterium-Tritium (D- T) nuclei is evaluated. Taking the Livermore mirror reference design mirror ratio of 6.54, the expected sin(sup 2) upsilon angular distribution of fusion decay products reduces immediate losses of alpha particles to the loss cone by 7.6% and alpha-ion scattering losses by approx. 50%. Based on these findings, alpha- particle confinement times for a polarized plasma should therefore be 1.11 times greater than for isotropic nuclei. Coupling this enhanced alpha-particle heating with the expected greater than 50% D- T reaction cross section, a corresponding power ratio for polarized nuclei, Q(sub polarized), is found to be 1.63 times greater than the classical unpolarized value Q(sub classical). The effects of this increase in Q are assessed for the simple mirror.

  3. Physics of mirror systems

    SciTech Connect

    Post, R.F.

    1982-05-01

    In recent years the emphasis in research on the magnetic mirror approach to fusion has been shifted to address what are essentially economically-motivated issues. The introduction of the Tandem Mirror idea solved in principal the problem of low Q (low fusion power gain) of mirror-based fusion systems. In order to optimize the tandem mirror idea from an economic standpoint, some important improvements have been suggested. These improvements include the thermal barrier idea of Baldwin and Logan and the axicell concept of Kesner. These new modifications introduce some special physics considerations. Among these are (1) The MHD stability properties of high energy electron components in the end cells; (2) The optimization of end-cell magnetic field configurations with the objective of minimizing equilibrium parallel currents; (3) The suppression of microstabilities by use of sloshing ion distributions. Following a brief outline of tandem mirror concepts, the above three topics are discussed, with illustrative examples taken from earlier work or from recent design studies.

  4. Cleaning procedure for mirror coating at Subaru Telescope

    NASA Astrophysics Data System (ADS)

    Yutani, Masami; Hayashi, Saeko S.; Kurakami, Tomio; Kanzawa, Tomio; Ohshima, Norio; Nakagiri, Masao

    2003-02-01

    We would like to present the procedure of how to prepare the primary mirror of Subaru Telescope for the realuminization. The equipment for the coating and its preparation are located at the ground floor of the telescope enclosure. There are two trolleys for carrying the mirror cell and the mirror itself, a mirror lifting jig, a washing facility for the primary mirror (PMWF), the water purification system, the coating chamber and the waste water pit. The PMWF can provide the tap water for initial rinsing, the chemical for stripping the old coating, and the deionized water for final cleaning. It has two pairs of arms that deploy horizontally above the mirror and have nozzles to spray. The arms spin around its center where the rotary joints are connected to the plumbing from storage tanks. Deck above the water arms serve as platform for personnel for the inspection or for scrubbing work. We use hydrochloric acid mixture to remove the old aluminum coating. For rinsing and final cleaning, we use the water through the purification system. The water supply from the nozzles and the rotation of the arms can be controlled from a panel separated from the washing machine itself. After several experiments and improvements in the washing, we have carried out the coating of the 8.3 m primary mirror in September last year. This was the third time, and the reflectivity of the new coating show satisfactory result.

  5. Smart materials optical mirrors

    NASA Astrophysics Data System (ADS)

    Chen, Peter C.; Rabin, Douglas M.

    2014-08-01

    We report the fabrication of imaging quality optical mirrors with smooth surfaces using carbon nanotubes embedded in an epoxy matrix. CNT/epoxy is a multifunctional or `smart' composite material that has sensing capabilities and can be made to incorporate self-actuation as well. Moreover, since the precursor is a low density liquid, large and lightweight mirrors can be fabricated by processes such as replication, spincasting, and 3D printing. The technology therefore holds promise for development of a new generation of lightweight, compact `smart' telescope mirrors with figure sensing and active or adaptive figure control. We report on measurements made of optical and mechanical characteristics. We discuss possible paths for future development.

  6. Next Generation Lightweight Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William; Fitzgerald, Matthew; Stahl, Philip

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models possible.

  7. Next-Generation Lightweight Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, Phil

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models possible

  8. Next Generation Lightweight Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William R., Sr.; Fitzgerald, Mathew; Rosa, Rubin Jaca; Stahl, H. Philip

    2013-01-01

    The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond machining of glasses and ceramics has created the need for more efficient means of generating finite element models of these structures. Traditional methods of assembling 400,000 + element models can take weeks of effort, severely limiting the range of possible optimization variables. This paper will introduce model generation software developed under NASA sponsorship for the design of both terrestrial and space based mirrors. The software deals with any current mirror manufacturing technique, single substrates, multiple arrays of substrates, as well as the ability to merge submodels into a single large model. The modeler generates both mirror and suspension system elements, suspensions can be created either for each individual petal or the whole mirror. A typical model generation of 250,000 nodes and 450,000 elements only takes 5-10 minutes, much of that time being variable input time. The program can create input decks for ANSYS, ABAQUS and NASTRAN. An archive/retrieval system permits creation of complete trade studies, varying cell size, depth, and petal size, suspension geometry with the ability to recall a particular set of parameters and make small or large changes with ease. The input decks created by the modeler are text files which can be modified by any editor, all the key shell thickness parameters are accessible and comments in deck identify which groups of elements are associated with these parameters. This again makes optimization easier. With ANSYS decks, the nodes representing support attachments are grouped into components; in ABAQUS these are SETS and in NASTRAN as GRIDPOINT SETS, this make integration of these models into large telescope or satellite models easier.

  9. Mirror Measurement Device

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Small Business Innovation Research (SBIR) contract led to a commercially available instrument used to measure the shape profile of mirror surfaces in scientific instruments. Bauer Associates, Inc.'s Bauer Model 200 Profilometer is based upon a different measurement concept. The local curvature of the mirror's surface is measured at many points, and the collection of data is computer processed to yield the desired shape profile. (Earlier profilometers are based on the principle of interferometry.) The system is accurate and immune to problems like vibration and turbulence. Two profilometers are currently marketed, and a third will soon be commercialized.

  10. Flat Focusing Mirror

    PubMed Central

    Cheng, Y. C.; Kicas, S.; Trull, J.; Peckus, M.; Cojocaru, C.; Vilaseca, R.; Drazdys, R.; Staliunas, K.

    2014-01-01

    The control of spatial propagation properties of narrow light beams such as divergence, focusing or imaging are main objectives in optics and photonics. In this letter, we propose and demonstrate experimentally a flat focusing mirror, based on an especially designed dielectric structure without any optical axis. More generally, it also enables imaging any light pattern in reflection. The flat focusing mirror with a transversal invariance can largely increase the applicability of structured photonic materials for light beam propagation control in small-dimension photonic circuits. PMID:25228358

  11. Transition Metal Switchable Mirror

    SciTech Connect

    2009-01-01

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  12. Transition Metal Switchable Mirror

    SciTech Connect

    2009-08-21

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  13. Transition Metal Switchable Mirror

    ScienceCinema

    None

    2016-07-12

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft. More information at: http://windows.lbl.gov/materials/chromogenics/default.htm

  14. Transition Metal Switchable Mirror

    ScienceCinema

    None

    2016-07-12

    The switchable-mirrors technology was developed by Tom Richardson and Jonathan Slack of Berkeley Lab's Environmental Energy Technologies Division. By using transition metals rather than the rare earth metals used in the first metal-hydride switchable mirrors, Richardson and Slack were able to lower the cost and simplify the manufacturing process. Energy performance is improved as well, because the new windows can reflect or transmit both visible and infrared light. Besides windows for offices and homes, possible applications include automobile sunroofs, signs and displays, aircraft windows, and spacecraft.

  15. Production of metal matrix composite mirrors for tank fire control systems

    NASA Astrophysics Data System (ADS)

    Geiger, Alan L.; Ulph, Eric, Sr.

    1992-09-01

    The first production lot of 50 units of metal matrix composite mirrors for the Leopard I tank fire control system was recently completed by Optical Corporation of America (OCA), Garden Grove, California. The mirror substrates were finish machined from forgings of Optical Grade SXATM metal matrix composite manufactured by Advanced Composite Materials Corporation (ACMC), Greer, South Carolina. Use of forgings rather than hot pressed billet yields more efficient use of material and reduces machining time, resulting in lower cost. The mirrors were fabricated by a process sequence of machining, thermal stabilization, electroless nickel plating, polishing, and coating with a high efficiency, laser damage-resistant optical coating. The mirrors are used in the fire control system for a day channel (direct view) and near infrared (CCD), a muzzle reference system laser transceiver, a laser range finder, and an infrared thermal imaging system. SXA composite was chosen over competitive mirror materials (glass and beryllium) because of its high specific strength and stiffness, good stability, and moderate machining cost. The mirrors exhibit excellent stability and optical performance. Field trials of prototype mirrors in fire control systems have proven successful.

  16. Fabrication of electroless nickel plated aluminum freeform mirror for an infrared off-axis telescope.

    PubMed

    Kim, Sanghyuk; Chang, Seunghyuk; Pak, Soojong; Lee, Kwang Jo; Jeong, Byeongjoon; Lee, Gil-jae; Kim, Geon Hee; Shin, Sang Kyo; Yoo, Song Min

    2015-12-01

    Freeform mirrors can be readily fabricated by a single point diamond turning (SPDT) machine. However, this machining process often leaves mid-frequency errors (MFEs) that generate undesirable diffraction effects and stray light. In this work, we propose a novel thin electroless nickel plating procedure to remove MFE on freeform surfaces. The proposed procedure has a distinct advantage over a typical thick plating method in that the machining process can be endlessly repeated until the designed mirror surface is obtained. This is of great importance because the sophisticated surface of a freeform mirror cannot be optimized by a typical SPDT machining process, which can be repeated only several times before the limited thickness of the nickel plating is consumed. We will also describe the baking process of a plated mirror to improve the hardness of the mirror surface, which is crucial for minimizing the degradation of that mirror surface that occurs during the polishing process. During the whole proposed process, the changes in surface figures and textures are monitored and cross checked by two different types of measurements, as well as by an interference pattern test. The experimental results indicate that the proposed thin electroless nickel plating procedure is very simple but powerful for removing MFEs on freeform mirror surfaces.

  17. Paranal Receives New Mirror

    NASA Astrophysics Data System (ADS)

    2008-04-01

    A 4.1-metre diameter primary mirror, a vital part of the world's newest and fastest survey telescope, VISTA (the Visible and Infrared Survey Telescope for Astronomy) has been delivered to its new mountaintop home at Cerro Paranal, Chile. The mirror will now be coupled with a small camera for initial testing prior to installing the main camera in June. Full scientific operations are due to start early next year. VISTA will form part of ESO's Very Large Telescope facility. ESO PR Photo 10d/08 ESO PR Photo 10d/08 The VISTA Mirror The mirror arrived over the Easter weekend at the Paranal Observatory where the telescope is being assembled at an altitude of 2518m, in Chile's Atacama Desert. VISTA Project Manager Alistair McPherson from STFC's UK Astronomy Technology Centre (UK ATC) accompanied the mirror on its journey to Chile: "This is a major milestone for the VISTA project. The precious mirror was loaded on to a plane in a special cradle that used tennis balls to cushion it from impact for its arduous journey across three continents. " "The mirror had a difficult four-day journey, by air and by road. It arrived in perfect condition and now that it has been coated, we will install the mirror in the telescope with a small test camera for about four weeks testing. We plan to install the main camera in June," said the Project Scientist on VISTA, Will Sutherland of Queen Mary, University of London, UK. The VISTA 4.1-metre diameter primary mirror is the most strongly curved large mirror ever polished to such a precise and exacting surface accuracy - deviations from a perfect surface of less than 1/3000th of the thickness of a human hair. On arrival at Cerro Paranal it was safely craned into the telescope dome where it was washed and coated with a thin layer of protected silver in the facility's coating plant. Silver is the best metal for the purpose since it reflects over 98% of near-infrared light, better than the more commonly used aluminium. To date, the reflectivity

  18. Database machines

    NASA Technical Reports Server (NTRS)

    Stiefel, M. L.

    1983-01-01

    The functions and performance characteristics of data base machines (DBM), including machines currently being studied in research laboratories and those currently offered on a commerical basis are discussed. The cost/benefit considerations that must be recognized in selecting a DBM are discussed, as well as the future outlook for such machines.

  19. JWST Mirror Technology Development

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2010-01-01

    Since the initial Design Studies leading to JWST, Mirror Technology was identified as a (if not the) critical capability necessary to enable the next generation of large aperture space telescopes required to achieve the science goals of imaging the earliest galaxies and proto-galaxies after the big bang. Specific telescope architectures were explored via three independent design concept studies conducted during the summer of 1996. Achieving the desired science objectives required a never before demonstrated space telescope capability, one with an 8 meter class primary mirror that is diffraction limited at 2 micrometers and operating in deep space at temperatures well below 70K. Beryllium was identified in the NASA "Yardstick" design as the preferred material because of its ability to provide stable optical performance in the anticipated thermal environment as well as its excellent specific stiffness. Because of launch vehicle constraints, two very significant architectural constraints were placed upon the telescope: segmentation and areal density. Each of these directly resulted in specific technology capability requirements. First, because the maximum launch vehicle payload fairing diameter is approximately 4.5 meters, the only way to launch an 8 meter class mirror is to segment it, fold it and deploy it on orbit - resulting in actuation and control requirements. Second, because of launch vehicle mass limits, the primary mirror allocation was only 1000 kg - resulting in a maximum areal density specification of 20 kilograms per square meter.

  20. Rearview Mirror Dimming Function

    ERIC Educational Resources Information Center

    Layton, William

    2011-01-01

    Students are often unaware of the little tab on a rear-view mirror that is used to dim headlights from the rear. Those who know about this tab are usually interested in knowing how it works. Explanations of the optics involved can be found in Serway and Jewett and Jones and Edge. An alternate explanation is given.

  1. Secondary mirror support (LST)

    NASA Technical Reports Server (NTRS)

    Schmidt, E. E.

    1973-01-01

    Large structural mirror supports which meet the stiff requirements for launch and orbit operations in particular, dimensionally stable structures made of titanium alloy, can be manufactured with present day technology and at reasonable cost. With continuing research and development in this area, designs of astronomical telescopes and related earth observatory satellites should benefit from this knowledge.

  2. Rearview Mirror Dimming Function

    NASA Astrophysics Data System (ADS)

    Layton, William

    2011-12-01

    Students are often unaware of the little tab on a rear-view mirror that is used to dim headlights from the rear. Those who know about this tab are usually interested in knowing how it works. Explanations of the optics involved can be found in Serway and Jewett and Jones and Edge.2 An alternate explanation is given below:

  3. Durable metallized polymer mirror

    DOEpatents

    Schissel, Paul O.; Kennedy, Cheryl E.; Jorgensen, Gary J.; Shinton, Yvonne D.; Goggin, Rita M.

    1994-01-01

    A metallized polymer mirror construction having improved durability against delamination and tunneling, comprising: an outer layer of polymeric material; a metal oxide layer underlying the outer layer of polymeric material; a silver reflective layer underneath the metal oxide layer; and a layer of adhesive attaching the silver layer to a substrate.

  4. Durable metallized polymer mirror

    DOEpatents

    Schissel, P.O.; Kennedy, C.E.; Jorgensen, G.J.; Shinton, Y.D.; Goggin, R.M.

    1994-11-01

    A metallized polymer mirror construction is disclosed having improved durability against delamination and tunneling, comprising: an outer layer of polymeric material; a metal oxide layer underlying the outer layer of polymeric material; a silver reflective layer underneath the metal oxide layer; and a layer of adhesive attaching the silver layer to a substrate. 6 figs.

  5. Cosmology with liquid mirror telescopes

    NASA Technical Reports Server (NTRS)

    Hogg, David W.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    Liquid mirrors provide an exciting means to obtain large optical telescopes for substantially lower costs than conventional technologies. The liquid mirror concept has been demonstrated in the lab with the construction of a diffraction limited 1.5 m mirror. The mirror surface, using liquid mercury, forms a perfect parabolic shape when the mirror cell is rotated at a uniform velocity. A liquid mirror must be able to support a heavy mercury load with minimal flexure and have a fundamental resonant frequency that is as high as possible, to suppress the amplitude of surface waves caused by small vibrations transmitted to the mirror. To minimize the transmission of vibrations to the liquid surface, the entire mirror rests on an air bearing. This necessitates the mirror cell being lightweight, due to the limited load capabilities of the air bearing. The mirror components must also have physical characteristics which minimize the effects of thermal expansion with ambient temperature fluctuations in the observatory. In addition, the 2.7 m mirror construction is designed so that the techniques used may be readily extended to the construction of large mirrors. To attain the goals of a lightweight, rigid mirror, a composite laminant construction was used. The mirror consists of a foam core cut to the desired parabolic shape, with an accuracy of a few mm. An aluminum hub serves as an anchor for the foam and skin, and allows precise centering of the mirror on the air bearing and drive system. Several plys of Kevlar, covered in an epoxy matrix, are then applied to the foam. A final layer of pure epoxy is formed by spin casting. This final layer is parabolic to within a fraction of a mm. An aluminum ring bonded to the circumference of the mirror retains the mercury, and incorporates stainless-steel hard-points for the attachment of balance weights.

  6. Required precision of mirror surface for solar furnace

    NASA Astrophysics Data System (ADS)

    Shishido, Koro; Shibata, Yukio; Sugiura, Masao; Shoji, Tetsuo

    1995-09-01

    The precision of beautifully finished quadratic surfaced mirrors is about +/- 1/10000th approximately +/- 1/15000th of a radian, performed by the experts, they are called 'Master'. These performances 'beautifully finished' have been done by Master's intuitions or experiences, so it is difficult for mass production of a high quality product. We are trying to reach the Master's territory by using mechanical methods. These are cam and link methods, link-gear-cam method, and glass gauge method. In these methods, the large solar furnace has been produced by cam method, the mirror was ground directly, then mirror precision reached in +/- 1/6000th aprroximately +/- 1/8000th of a radian. In another method, link method, link-gear-cam method, and glass gauge method are used for production of quadratic surfaces master molds, and the glass plates are softened for the quadratic surfaced mirror by these master molds. For example, the precision of the master molds which was fabricated by the cutting machine constructed from the link-gear-cam mechanisms are +/- 1/3000th of a radian, and the precision of master molds which was fabricated by the glass gauge cutting machine are +/- 1/6000th approximately +/- 1/7000th of a radian. Lately, we have considered the quadratic cutting machine constructed from the cylinder type tool for the large diameter of the quadratic surfaces.

  7. Mirror Image Agnosia

    PubMed Central

    Chandra, Sadanandavalli Retnaswami; Issac, Thomas Gregor

    2014-01-01

    Background: Gnosis is a modality-specific ability to access semantic knowledge of an object or stimulus in the presence of normal perception. Failure of this is agnosia or disorder of recognition. It can be highly selective within a mode. self-images are different from others as none has seen one's own image except in reflection. Failure to recognize this image can be labeled as mirror image agnosia or Prosopagnosia for reflected self-image. Whereas mirror agnosia is a well-recognized situation where the person while looking at reflected images of other objects in the mirror he imagines that the objects are in fact inside the mirror and not outside. Material and Methods:: Five patients, four females, and one male presented with failure to recognize reflected self-image, resulting in patients conversing with the image as a friend, fighting because the person in mirror is wearing her nose stud, suspecting the reflected self-image to be an intruder; but did not have prosopagnosia for others faces, non living objects on self and also apraxias except dressing apraxia in one patient. This phenomena is new to our knowledge. Results: Mirror image agnosia is an unique phenomena which is seen in patients with parietal lobe atrophy without specificity to a category of dementing illness and seems to disappear as disease advances. Discussion: Reflected self-images probably have a specific neural substrate that gets affected very early in posterior dementias specially the ones which predominantly affect the right side. At that phase most patients are mistaken as suffering from psychiatric disorder as cognition is moderately preserved. As disease becomes more widespread this symptom becomes masked. A high degree of suspicion and proper assessment might help physicians to recognize the organic cause of the symptom so that early therapeutic interventions can be initiated. Further assessment of the symptom with FMRI and PET scan is likely to solve the mystery of how brain handles

  8. Algorithm for ion beam figuring of low-gradient mirrors.

    PubMed

    Jiao, Changjun; Li, Shengyi; Xie, Xuhui

    2009-07-20

    Ion beam figuring technology for low-gradient mirrors is discussed. Ion beam figuring is a noncontact machining technique in which a beam of high-energy ions is directed toward a target workpiece to remove material in a predetermined and controlled fashion. Owing to this noncontact mode of material removal, problems associated with tool wear and edge effects, which are common in conventional contact polishing processes, are avoided. Based on the Bayesian principle, an iterative dwell time algorithm for planar mirrors is deduced from the computer-controlled optical surfacing (CCOS) principle. With the properties of the removal function, the shaping process of low-gradient mirrors can be approximated by the linear model for planar mirrors. With these discussions, the error surface figuring technology for low-gradient mirrors with a linear path is set up. With the near-Gaussian property of the removal function, the figuring process with a spiral path can be described by the conventional linear CCOS principle, and a Bayesian-based iterative algorithm can be used to deconvolute the dwell time. Moreover, the selection criterion of the spiral parameter is given. Ion beam figuring technology with a spiral scan path based on these methods can be used to figure mirrors with non-axis-symmetrical errors. Experiments on SiC chemical vapor deposition planar and Zerodur paraboloid samples are made, and the final surface errors are all below 1/100 lambda.

  9. Congenital mirror movements.

    PubMed Central

    Schott, G D; Wyke, M A

    1981-01-01

    In this report are described seven patients assessed clinically and neuropsychologically in whom mirror movements affecting predominantly the hands occurred as a congenital disorder. These mirror movements, representing a specific type of abnormal synkinesia, may arise as a hereditary condition, in the presence of a recognisable underlying neurological abnormality, and sporadically, and the seven patients provide more or less satisfactory examples of each of these three groups. Despite the apparent uniformity of the disorder, the heterogeneity and variability may be marked, examples in some of our patients including the pronounced increase in tone that developed with arm movement, and the capacity for modulation of the associated movement by alteration of neck position and bio-feedback. Various possible mechanisms are considered; these include impaired cerebral inhibition of unwanted movements, and functioning of abnormal motor pathways. Emphasis has been placed on the putative role of the direct, crossed corticomotoneurone pathways and on the unilateral and bilateral cerebral events that precede movement. PMID:7288446

  10. Dynamic coherent backscattering mirror

    PubMed Central

    Xu, M.

    2016-01-01

    The phase of multiply scattered light has recently attracted considerable interest. Coherent backscattering is a striking phenomenon of multiple scattered light in which the coherence of light survives multiple scattering in a random medium and is observable in the direction space as an enhancement of the intensity of backscattered light within a cone around the retroreflection direction. Reciprocity also leads to enhancement of backscattering light in the spatial space. The random medium behaves as a reciprocity mirror which robustly converts a diverging incident beam into a converging backscattering one focusing at a conjugate spot in space. Here we first analyze theoretically this coherent backscattering mirror (CBM) phenomenon and then demonstrate the capability of CBM compensating and correcting both static and dynamic phase distortions occurring along the optical path. CBM may offer novel approaches for high speed dynamic phase corrections in optical systems and find applications in sensing and navigation. PMID:26937296

  11. Dynamic coherent backscattering mirror

    SciTech Connect

    Zeylikovich, I.; Xu, M.

    2016-02-15

    The phase of multiply scattered light has recently attracted considerable interest. Coherent backscattering is a striking phenomenon of multiple scattered light in which the coherence of light survives multiple scattering in a random medium and is observable in the direction space as an enhancement of the intensity of backscattered light within a cone around the retroreflection direction. Reciprocity also leads to enhancement of backscattering light in the spatial space. The random medium behaves as a reciprocity mirror which robustly converts a diverging incident beam into a converging backscattering one focusing at a conjugate spot in space. Here we first analyze theoretically this coherent backscattering mirror (CBM) phenomenon and then demonstrate the capability of CBM compensating and correcting both static and dynamic phase distortions occurring along the optical path. CBM may offer novel approaches for high speed dynamic phase corrections in optical systems and find applications in sensing and navigation.

  12. Lightweight Substrates For Mirrors

    NASA Technical Reports Server (NTRS)

    Brown, D. Kyle

    1991-01-01

    New substrate uses conventional quasi-isotropic fabric laminate with surfacing layer of carbon-fiber paper consisting of randomly oriented chopped carbon fibers. Layered structure of fabric and paper relatively easy to manufacture. When impregnated with carbon, structure rigid and stable. Substrates of this type made quite thin, thus keeping areal weights to minimum. Mirrors of this type made faster, and cost less, than predecessors.

  13. Joined Beryllium Mirror Demonstrator

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Parsonage, Tom; Burdine, Robert (Technical Monitor)

    2001-01-01

    Fabrications of large Beryllium optical components are fundamentally limited by available facility capabilities. To overcome this limitation, NASA funded Brush Wellman Corp to study a Be joining process. Four 76 mm diameters samples and a 0.5 mm diameter Joined Beryllium Mirror Demonstrator (JBMD) were fabricated. This presentation will review the fabrication of these samples and summarize the results of their cryogenic testing at MSFCs XRCF.

  14. Advanced Curvature Deformable Mirrors

    DTIC Science & Technology

    2010-09-01

    designs using just a glass wafer and a wafer of Carbon Fiber Reinforced Polymer ( CFRP ). In both cases minimum bend radius decreases and the resonant... matrix is consequently nearly diagonal. The long actuators at the outer edge of the deformable mirror are largely outside the working pupil so their...formal reconstruction of the wave front either explicitly or implicitly in the control matrix . The WFS-DM combination is acting like an analog computer

  15. Diamond fly cutting of aluminum thermal infrared flat mirrors for the OSIRIS-REx Thermal Emission Spectrometer (OTES) instrument

    NASA Astrophysics Data System (ADS)

    Groppi, Christopher E.; Underhill, Matthew; Farkas, Zoltan; Pelham, Daniel

    2016-07-01

    We present the fabrication and measurement of monolithic aluminum flat mirrors designed to operate in the thermal infrared for the OSIRIS-Rex Thermal Emission Spectrometer (OTES) space instrument. The mirrors were cut using a conventional fly cutter with a large radius diamond cutting tool on a high precision Kern Evo 3-axis CNC milling machine. The mirrors were measured to have less than 150 angstroms RMS surface error.

  16. Mirror agnosia and mirror ataxia constitute different parietal lobe disorders.

    PubMed

    Binkofski, F; Buccino, G; Dohle, C; Seitz, R J; Freund, H J

    1999-07-01

    We describe two new clinical syndromes, mirror agnosia and mirror ataxia, both characterized by the deficit of reaching for an object through a mirror in association with a lesion of either parietal lobe. Clinical investigation of 13 patients demonstrated that the impairments affected both sides of the body. In mirror agnosia, the patients always reached toward the virtual object in the mirror and they were not capable of changing their behavior even after presentation of the position of the object in real visual space. In mirror ataxia (resembling optic ataxia) although some patients initially tended to reach for the virtual object in the mirror, they soon learned to guide their arms toward the real object, all of them producing many directional errors. Both patient groups performed poorly on mental rotation, but only the patients with mirror agnosia were impaired in line orientation. Only 1 of the patients suffered from neglect and 3 from apraxia. Magnetic resonance imaging showed that in mirror agnosia the common zone of lesion overlap was scattered around the posterior angular gyrus/superior temporal gyrus and in mirror ataxia around the postcentral sulcus. We propose that both these clinical syndromes may represent different types of dissociation of retinotopic space and body scheme, or likewise, of allocentric and egocentric space normally adjusted in the parietal lobe.

  17. Replication of lightweight mirrors

    NASA Astrophysics Data System (ADS)

    Chen, Ming Y.; Matson, Lawrence E.; Lee, Heedong; Chen, Chenggang

    2009-08-01

    The fabrication of lightweight mirror assemblages via a replication technique offers great potential for eliminating the high cost and schedule associated with the grinding and polishing steps needed for conventional glass or SiC mirrors. A replication mandrel is polished to an inverse figure shape and to the desired finish quality. It is then, coated with a release layer, the appropriate reflective layer, and followed by a laminate for coefficient of thermal expansion (CTE) tailorability and strength. This optical membrane is adhered to a mirror structural substrate with a low shrinkage, CTE tailored adhesive. Afterwards, the whole assembly is separated from the mandrel. The mandrel is then cleaned and reused for the next replication run. The ultimate goal of replication is to preserve the surface finish and figure of the optical membrane upon its release from the mandrel. Successful replication requires a minimization of the residual stresses within the optical coating stack, the curing stresses from the adhesive and the thermal stress resulting from CTE mismatch between the structural substrate, the adhesive, and the optical membrane. In this paper, the results on replicated trials using both metal/metal and ceramic/ceramic laminates adhered to light weighted structural substrates made from syntactic foams (both inorganic and organic) will be discussed.

  18. LDR segmented mirror technology assessment study

    NASA Technical Reports Server (NTRS)

    Krim, M.; Russo, J.

    1983-01-01

    In the mid-1990s, NASA plans to orbit a giant telescope, whose aperture may be as great as 30 meters, for infrared and sub-millimeter astronomy. Its primary mirror will be deployed or assembled in orbit from a mosaic of possibly hundreds of mirror segments. Each segment must be shaped to precise curvature tolerances so that diffraction-limited performance will be achieved at 30 micron (nominal operating wavelength). All panels must lie within 1 micron on a theoretical surface described by the optical precipitation of the telescope's primary mirror. To attain diffraction-limited performance, the issues of alignment and/or position sensing, position control of micron tolerances, and structural, thermal, and mechanical considerations for stowing, deploying, and erecting the reflector must be resolved. Radius of curvature precision influences panel size, shape, material, and type of construction. Two superior material choices emerged: fused quartz (sufficiently homogeneous with respect to thermal expansivity to permit a thin shell substrate to be drape molded between graphite dies to a precise enough off-axis asphere for optical finishing on the as-received a segment) and a Pyrex or Duran (less expensive than quartz and formable at lower temperatures). The optimal reflector panel size is between 1-1/2 and 2 meters. Making one, two-meter mirror every two weeks requires new approaches to manufacturing off-axis parabolic or aspheric segments (drape molding on precision dies and subsequent finishing on a nonrotationally symmetric dependent machine). Proof-of-concept developmental programs were identified to prove the feasibility of the materials and manufacturing ideas.

  19. Procedure for computer-controlled milling of accurate surfaces of revolution for millimeter and far-infrared mirrors

    NASA Technical Reports Server (NTRS)

    Emmons, Louisa; De Zafra, Robert

    1991-01-01

    A simple method for milling accurate off-axis parabolic mirrors with a computer-controlled milling machine is discussed. For machines with a built-in circle-cutting routine, an exact paraboloid can be milled with few computer commands and without the use of the spherical or linear approximations. The proposed method can be adapted easily to cut off-axis sections of elliptical or spherical mirrors.

  20. Comparison of Stress Relief Procedures for Cryogenic Aluminum Mirrors

    NASA Technical Reports Server (NTRS)

    Ohl, Raymond G.; Barthelmy, Michael P.; Zewari, S. Wahid; Toland, Ronald; Mink, Ronald; Mentzell, J. Eric; Greenhouse, Matthew A.; McMann, Joseph C.; Hylan, Jason; Hagopian, John G.; Krebs, Carolyn (Technical Monitor)

    2002-01-01

    The Infrared Multi-Object Spectrograph (IRMOS) is a facility instrument for the Kitt Peak National Observatory Mayall Telescope (3.8 meter) and an engineering prototype for a potential design for the Next Generation Space Telescope/Multi-Object Spectrograph. IRMOS is a low-to mid-resolution (R = lambda/delta-lambda = 300-3800), near-IR (0.8-2.5 micron) spectrograph which produces simultaneous spectra of approximately 100 objects in its 2.8 x 2.0 arcmin field of view using a commercial MEMS multimirror array device. The instrument operating temperature is 80 K and the design is athermal --- the optical bench and mirrors are machined from aluminum 6061-T651. In spite of its baseline mechanical stress relief, aluminum 6061-T651 harbors some residual stress, which, unless relieved during fabrication, may relieve and distort mirror figure to unacceptable levels at the operating temperature. Other cryogenic instruments using aluminum mirrors for both ground-based and space IR astronomy have employed a variety of heat treatment formulae, with mixed results. We present the results of a test program designed to empirically determine the best stress relief procedure for the IRMOS mirrors. Identical test mirrors with spherical and flat optical prescriptions are processed with five different heat treatment formulae from the literature and compared to samples with out any additional processing. After figuring via diamond turning, the mirrors are tested for figure error and radius of curvature at room temperature and at 80 K for several thermal cycles. The heat treatment procedure for the mirrors that yielded the least and most repeatable change in figure error and radius is applied to the IRMOS mirror blanks. We correlate the results of our optical testing with heat treatment and metallographic data.

  1. Two-mirror optical system with a small fold mirror

    NASA Astrophysics Data System (ADS)

    Liu, Xinping; Li, Yingcai; Yang, Jianfeng

    1998-09-01

    A new configuration of two-mirror optical system with a small fold mirror is presented in this paper. Consisting of a concave (positive power) primary mirror followed by a small flat mirror, a concave (positive power) secondary mirror, four lenses and a beam splitter, it gives the excellent image quality. A 1.5-m EFL, F/10 system of the upper configuration is designed over the 4 degree(s) field angle and 0.50 approximately 0.70 micrometers wavelength range. The aberrations have been highly corrected and the distortion is less than 0.3% over the field. The obscuration could be minimized by reducing primary radius of curvature and avoiding the spider that holds the small fold mirror.

  2. A spectrum of shadowed mirroring.

    PubMed

    Wanamaker, Melissa C

    2012-04-01

    The central focus of this paper is to explore and extend Kohut's theory of maternal mirroring and to place it within the current context of psychoanalytic thinking. Kohut believed a child must experience "positive" mirroring from his or her mother in infancy and beyond to ensure development of a healthy self. Kohut alludes, however, to a possible situation in which the mother's face, metaphorically a mirror, can appear "faceless" to her child. From this I have inferred the concept of what I shall call "shadowed mirroring." Clinical and literary examples show that distorted, "shadowed" mirroring appears on a spectrum, with passive mirroring at one end and hostile (either verbal or nonverbal) mirroring on the other; some individuals experience both. I then consider how "shadowed mirroring," especially hostile mirroring, can be understood within the twin contexts of the overall mother-child relationship and present-day Intersubjective/Relational thinking that is both bidirectional and co-constructed. Shadowed mirroring can lead to severe personality dysfunction along the borderline-narcissistic range, as well as to difficulties in the areas of identity formation, failure of self-cohesiveness, and the blunting of certain humane qualities like empathy.

  3. Design of optical mirror structures

    NASA Technical Reports Server (NTRS)

    Soosaar, K.

    1971-01-01

    The structural requirements for large optical telescope mirrors was studied with a particular emphasis placed on the three-meter Large Space Telescope primary mirror. Analysis approaches through finite element methods were evaluated with the testing and verification of a number of element types suitable for particular mirror loadings and configurations. The environmental conditions that a mirror will experience were defined and a candidate list of suitable mirror materials with their properties compiled. The relation of the mirror mechanical behavior to the optical performance is discussed and a number of suitable design criteria are proposed and implemented. A general outline of a systematic method to obtain the best structure for the three-meter diffraction-limited system is outlined. Finite element programs, using the STRUDL 2 analysis system, were written for specific mirror structures encompassing all types of active and passive mirror designs. Parametric studies on support locations, effects of shear deformation, diameter to thickness ratios, lightweight and sandwich mirror configurations, and thin shell active mirror needs were performed.

  4. Electric machine

    DOEpatents

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  5. A tandem mirror plasma source for hybrid plume plasma studies

    NASA Technical Reports Server (NTRS)

    Yang, T. F.; Chang, F. R.; Miller, R. H.; Wenzel, K. W.; Krueger, W. A.

    1985-01-01

    A tandem mirror device to be considered as a hot plasma source for the hybrid plume rocket concept is discussed. The hot plamsa from this device is injected into an exhaust duct, which will interact with an annular hypersonic layer of neutral gas. The device can be used to study the dynamics of the hybrid plume, and to verify the numerical predictions obtained with computer codes. The basic system design is also geared towards low weight and compactness, and high power density at the exhaust. The basic structure of the device consists of four major subsystems: (1) an electric power supply; (2) a low temperature, high density plasma gun, such as a stream gun, an MPD source or gas cell; (3) a power booster in the form of a tandem mirror machine; and (4) an exhaust nozzle arrangement. The configuration of the tandem mirror section is shown.

  6. Plasma performance study for the tandem mirror reactor

    SciTech Connect

    Boghosian, B.M.

    1980-01-01

    A computer code was developed for assessing the performance of new variations on the thermal barrier idea for tandem mirror reactors (TMR's). The code solves the particle and energy balance equations simultaneously for each species of particles in each portion of the machine. The code is thus able to determine the neutral beam and ECRH injection powers that are required to sustain an equilibrium situation, and, from these, to determine the machine's Q value. This paper focuses on the methodology and numerical algorithms used in accomplishing this solution. We plan to use this code to compare the A-cell barrier TMR with axisymmetric TMR's.

  7. Variable focal length deformable mirror

    DOEpatents

    Headley, Daniel; Ramsey, Marc; Schwarz, Jens

    2007-06-12

    A variable focal length deformable mirror has an inner ring and an outer ring that simply support and push axially on opposite sides of a mirror plate. The resulting variable clamping force deforms the mirror plate to provide a parabolic mirror shape. The rings are parallel planar sections of a single paraboloid and can provide an on-axis focus, if the rings are circular, or an off-axis focus, if the rings are elliptical. The focal length of the deformable mirror can be varied by changing the variable clamping force. The deformable mirror can generally be used in any application requiring the focusing or defocusing of light, including with both coherent and incoherent light sources.

  8. JWST Mirror Technology Development Results

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2007-01-01

    Mirror technology is a critical enabling capability for the James Webb Space Telescope (JWST). JWST requires a Primary Mirror Segment Assembly (PMSA) that can survive launch, deploy and align itself to form a 25 square meter collecting area 6.5 meter diameter primary mirror with a 131 nm rms wavefront error at temperatures less than 50K and provide stable optical performance. At the inception of JWST in 1996, such a capability did not exist. A highly successful technology development program was initiated including the Sub-scale Beryllium Mirror Demonstrator (SBMD) and Advanced Mirror System Demonstrator (AMSD) projects. These projects along with flight program activities have matured and demonstrated mirror technology for JWST. Directly traceable prototypes or flight hardware has been built, tested and operated in a relevant environment. This paper summarizes that technology development effort.

  9. Optical parametric loop mirror

    NASA Astrophysics Data System (ADS)

    Mori, K.; Morioka, T.; Saruwatari, M.

    1995-06-01

    A novel configuration for four-wave mixing (FWM) is proposed that offers the remarkable feature of inherently separating the FWM wave from the input pump and signal waves and suppressing their background amplified stimulated emission without optical filtering. In the proposed configuration, an optical parametric loop mirror, two counterpropagating FWM waves generated in a Sagnac interferometer interfere with a relative phase difference that is introduced deliberately. FWM frequency-conversion experiments in a polarization-maintaining fiber achieved more than 35 dB of input-wave suppression against the FWM wave.

  10. SXI Prototype mirror mount

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This final report describes the work performed from June 1993 to January 1995. The purpose of this contract was to provide optomechanical engineering and fabrication support to the Solar X-ray Imager (SXI) program in the areas of mirror, optical bench and camera assemblies of the telescope. The Center for Applied Optics (CAO) worked closely with the Optics and S&E technical staff of MSFC to develop and investigate the most viable and economical options for the design and fabrication of a number of parts for the various telescope assemblies. All the tasks under this delivery order have been successfully completed within budget and schedule.

  11. Negative tandem mirror

    SciTech Connect

    Poulsen, P.; Allen, S.L.; Casper, T.A.; Grubb, D.P.; Jong, R.A.; Nexsen, W.E.; Porter, G.D.; Simonen, T.C.

    1981-11-30

    A tandem mirror configuration can be created by combining hot electron end cell plasmas with neutral beam pumping. A region of large negative potential formed in each end cell confines electrons in the central cell. The requirement of charge neutrality causes the central cell potential to become negative with respect to ground in order to confine ions as well as electrons. We discuss the method of producing and calculating the desired axial potential profile, and show the calculated axial potential profile and plasma parameters for a negative configuration of TMX-Upgrade.

  12. Poco Graphite Mirror Metrology Report

    NASA Technical Reports Server (NTRS)

    Kester, Thomas J.

    2005-01-01

    Recently a lightweight mirror technology was tested at Marshall Space Flight Center's Space Optic Manufacturing Technology Center (MSFC, SOMTC). The mirror is a Poco Graphite CVD Si clad SiC substrate. It was tested for cryogenic (cryo) survivability to 20deg Kelvin in SOMTC's X-ray Calibration and Cryogenic Test Facility. The surface figure of the mirror was measured before and after cry0 cycling. The test technique and results are discussed.

  13. Control of micromachined deformable mirrors

    NASA Technical Reports Server (NTRS)

    Agronin, M. L.; Bartman, R.; Hadaegh, F. Y.; Kaiser, W.; Wang, P. K. C.

    1993-01-01

    A micromachined deformable mirror with pixelated electrostatic actuators is proposed. The paper begins with a physical description of the proposed mirror. Then a mathematical model in the form of a nonlinear partial differential equation describing the mirror surface deformations is derived. This model is used to derive the required voltages for the actuators to achieve a specified static deformation of the mirror surface. This is followed by the derivation of a static nonlinear feedback controller for achieving noninteracting actuation. Then the structure for a complete control system for wavefront correction is proposed. The paper concludes with a discussion of the physical implementation of the proposed control system.

  14. JWST Primary Mirror Technology Development

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2010-01-01

    Mirror Technology was identified as a (if not the) critical capability necessary to achieve the Level 1 science goals. A never before demonstrated space telescope capability was required: 6 to 8 meter class pri mary mirror, diffraction limited at 2 micrometers and operates at temperatures below 50K. Launch vehicle constraints placed significant architectural constraints: deployed/segmented primary mirror (4.5 meter fairing diameter) 20 kg/m2 areal density (PM 1000 kg mass) Such mirror technology had never been demonstrated - and did not exist

  15. Mirror development for CTA

    NASA Astrophysics Data System (ADS)

    Förster, A.; Doro, M.; Brun, P.; Canestrari, R.; Chadwick, P.; Font, L.; Ghigo, M.; Lorenz, E.; Mariotti, M.; Michalowski, J.; Niemiec, J.; Pareschi, G.; Peyaud, B.; Seweryn, K.

    2009-08-01

    The Cherenkov Telescope Array (CTA), currently in its early design phase, is a proposed new project for groundbased gamma-ray astronomy with at least 10 times higher sensitivity than current instruments. CTA is planned to consist of several tens of large Imaging Atmospheric Cherenkov Telescopes (IACTs) with a combined reflective surface of up to 10,000 m2. The challenge for the future CTA array is to develop lightweight and cost efficient mirrors with high production rates, good longterm durability and adequate optical properties. The technologies currently under investigation comprise different methods of carbon fibre/epoxy based substrates, sandwich concepts with cold-slumped surfaces made of thin float glass and different structural materials like aluminum honeycomb, glass foam or PU foam inside, and aluminum sandwich structures with either diamond milled surfaces or reflective foils. The current status of the mirror development for CTA will be summarized together with investigations on the improvement of the reflective surfaces and their protection against degradation.

  16. Buildup studies of a tandem mirror reactor with inboard thermal barriers

    SciTech Connect

    Gryczkowski, G.E.; Gilmore, J.M.

    1980-10-09

    The build-up and quasi-steady state phases of the operation of the tandem mirror experiment, TMX, and of a tandem mirror machine with inboard thermal barriers, MFTF-B, have been simulated using a fluid model of the central cell and plug plasmas. The fluid model incorporates classical radial transport, three-dimensional cold gas transport in cylindrical geometry, and neutral beam transport corrected for finite-Larmor-orbit effects in both the central cell and yin yang end plugs.

  17. Development of lightweight mirror elements for the Euro50 mirrors

    NASA Astrophysics Data System (ADS)

    Bennett, Harold E.; Romeo, Robert C.; Shaffer, Joseph J.; Chen, Peter C.

    2004-07-01

    New, very large telescopes with apertures of 30, 50, and 100 meters are being proposed by the astronomical community. Superpolished or ultrapolished mirrors with low scattered light levels and the use of adaptive optics for near-diffraction-limited performance would make such large telescopes a turning point in astronomy. The secondary mirror for the Euro50 will be a four meter adaptive optic made of a low expansion graphite-filled cyanate ester resin composite produced using a replica transfer technique. We have made three 1/3rd meter diameter prototype composite adaptive optic mirrors of this cyanate ester composite material. Because of the embedded graphite fibers, the composite material has a measured expansion coefficient in the 10-8 range, as has Zerodur or ULE glass. It is very much lighter, more rugged and more economical than Zerodur or ULE, and can be fabricated in weeks, not months. The Zerodur mandrels upon which these replica transfer mirrors are made are superpolished using centrifugal elutriation, so the replica surface has an rms roughness of 0.6 to 0.8 nm. It thus scatters about an order of magnitude less light than typical conventionally polished astronomical mirrors. In adaptive optic mirrors with sub-mm thick faceplates the number of plies used is insufficient to produce an isotropic surface. For mirrors 2 mm thick, with more plies, the surfaces are isotropic, and the slight astigmatism sometimes resulting from the mesh in the ply can be corrected by actuators to make them attractive mirrors. They must be supported to maintain a good optical figure over a meter diameter mirror. The support requirement may be met by using a new type of mechanical/piezoelectric actuator adjustable to a fraction of a wavelength. The mechanical actuators have a coarse adjust of over an mm and a fine adjust of less than a wavelength of light. They can be used in series with a novel type of piezoelectric actuator for final static adjustment. The low voltage, up to 2

  18. Mirror profile optimization for nano-focusing KB mirror

    SciTech Connect

    Zhang Lin; Baker, Robert; Barrett, Ray; Cloetens, Peter; Dabin, Yves

    2010-06-23

    A KB focusing mirror width profile has been optimized to achieve nano-focusing for the nano-imaging end-station ID22NI at the ESRF. The complete mirror and flexure bender assembly has been modeled in 3D with finite element analysis using ANSYS. Bender stiffness, anticlastic effects and geometrical non-linear effects have been considered. Various points have been studied: anisotropy and crystal orientation, stress in the mirror and bender, actuator resolution and the mirror-bender adhesive bonding... Extremely high performance of the mirror is expected with residual slope error smaller than 0.6 {mu}rad, peak-to-valley, compared to the bent slope of 3000 {mu}rad.

  19. Study on supporting force sensing and control during large aperture space mirror test

    NASA Astrophysics Data System (ADS)

    Zhang, Long; Hu, Wenqi; Zheng, Liehua; Hao, Peiming

    2016-10-01

    During the machining of large aperture lightweight space mirror, the mirror figure consistency between ground test and space mission is a problem. In order to effectively control the supporting deformation effect on test results in gravity environment, in view of a 1.2-m space mirror with back blind holes, a supporting method for optical axis horizontal test is proposed, with this method, mirror under test is positioned by three center hole surfaces and supported by six external hole surfaces. The effect of deformation caused by different supporting force value, area and position is analyzed by finite element method, the simulation results show that this supporting method can control the mirror supporting deformation within PV0.035λ rms0.005λ. The actual supporting system uses soft expansion mandrel to control the mirror position and pneumatic lever to realize the floating support. In order to ensure that the support force can evenly distribute on the contact surface, a pressure mapping system is adopted to measure the interface pressure between the mirror blind holes and the soft supporting pads for the first time. This method can meet the test requirements of rms=1/40λ mirror and provides a technical support for high precision test of large aperture space mirror with back blind holes.

  20. New fabrication method for an ellipsoidal neutron focusing mirror with a metal substrate.

    PubMed

    Guo, Jiang; Takeda, Shin; Morita, Shin-ya; Hino, Masahiro; Oda, Tatsuro; Kato, Jun-ichi; Yamagata, Yutaka; Furusaka, Michihiro

    2014-10-06

    We propose an ellipsoidal neutron focusing mirror using a metal substrate made with electroless nickel-phosphorus (NiP) plated material for the first time. Electroless NiP has great advantages for realizing an ellipsoidal neutron mirror because of its amorphous structure, good machinability and relatively large critical angle of total reflection for neutrons. We manufactured the mirror by combining ultrahigh precision cutting and fine polishing to generate high form accuracy and low surface roughness. The form accuracy of the mirror was estimated to be 5.3 μm P-V and 0.8 μm P-V for the minor-axis and major-axis direction respectively, while the surface roughness was reduced to 0.2 nm rms. The effect of form error on focusing spot size was evaluated by using a laser beam and the focusing performance of the mirror was verified by neutron experiments.

  1. Forming Mirrors on Composite Materials

    NASA Technical Reports Server (NTRS)

    Gauldin, R. E.; Ramohalli, K.

    1983-01-01

    Smooth coatings deposited on hard-to-polish substrates. Lightweight mirror, leaning against conventional glass mirror, consists of metallic relective layer on substrate coated with polyester resin. Smooth surface of polyester resin made by covering freshly applied resin with piece of smooth glass coated with release agent.

  2. Polishing technique for beryllium mirror

    NASA Technical Reports Server (NTRS)

    Froechtenigt, J. F.

    1976-01-01

    Performance tests, accomplished by inserting entire X ray telescope and polished mirror into vacuum line 67 m long and taking photographs of an X ray resolution source, indicate that polishing increases mirror efficiency from 0.06 percent for X rays at 0.8 nm and increases resolution from 15 to 3.75 arc-seconds.

  3. Eliminating mirror responses by instructions.

    PubMed

    Bardi, Lara; Bundt, Carsten; Notebaert, Wim; Brass, Marcel

    2015-09-01

    The observation of an action leads to the activation of the corresponding motor plan in the observer. This phenomenon of motor resonance has an important role in social interaction, promoting imitation, learning and action understanding. However, mirror responses not always have a positive impact on our behavior. An automatic tendency to imitate others can introduce interference in action execution and non-imitative or opposite responses have an advantage in some contexts. Previous studies suggest that mirror tendencies can be suppressed after extensive practice or in complementary joint action situations revealing that mirror responses are more flexible than previously thought. The aim of the present study was to gain insight into the mechanisms that allow response flexibility of motor mirroring. Here we show that the mere instruction of a counter-imitative mapping changes mirror responses as indexed by motor evoked potentials (MEPs) enhancement induced by transcranial magnetic stimulation (TMS). Importantly, mirror activation was measured while participants were passively watching finger movements, without having the opportunity to execute the task. This result suggests that the implementation of task instructions activates stimulus-response association that can overwrite the mirror representations. Our outcome reveals one of the crucial mechanisms that might allow flexible adjustments of mirror responses in different contexts. The implications of this outcome are discussed.

  4. Acoustic Models of Optical Mirrors

    ERIC Educational Resources Information Center

    Mayer, V. V.; Varaksina, E. I.

    2014-01-01

    Students form a more exact idea of the action of optical mirrors if they can observe the wave field being formed during reflection. For this purpose it is possible to organize model experiments with flexural waves propagating in thin elastic plates. The direct and round edges of the plates are used as models of plane, convex and concave mirrors.…

  5. Shell Separation for Mirror Replication

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. Optics replication uses reusable forms, called mandrels, to make telescope mirrors ready for final finishing. MSFC optical physicist Bill Jones monitors a device used to chill a mandrel, causing it to shrink and separate from the telescope mirror without deforming the mirror's precisely curved surface.

  6. Electrons and Mirror Symmetry

    ScienceCinema

    Kumar, Krishna

    2016-07-12

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  7. Electrons and Mirror Symmetry

    SciTech Connect

    Kumar, Krishna

    2007-04-04

    The neutral weak force between an electron and a target particle, mediated by the Z boson, can be isolated by measuring the fractional change under a mirror reflection of the scattering probability of relativistic longitudinally polarized electrons off unpolarized targets. This technique yields neutral weak force measurements at a length scale of 1 femtometer, in contrast to high energy collider measurements that probe much smaller length scales. Study of the variation of the weak force over a range of length scales provides a stringent test of theory, complementing collider measurements. We describe a recent measurement of the neutral weak force between two electrons by the E158 experiment at the Stanford Linear Accelerator Center. While the weak force between an electron and positron has been extensively studied, that between two electrons had never directly been measured. We conclude by discussing prospects for even more precise measurements at future facilities.

  8. Deformation analysis of a lightweight metal mirror

    NASA Astrophysics Data System (ADS)

    Zhou, Jianwei; Lin, Wumei; Liu, Guoqing; Xing, Tingwen

    2005-02-01

    The weight of the optical elements of a system used in the aviation and aerospace industry must be as light as possible, on condition that the imaging performance of the system satisfies user"s demand. However, optical elements will deform easily under internal or external pressure if it becomes thinner, and then influences the imaging performance of the whole optical system. In this paper, the main mirror of the Cassegrain system is studied with finite-element analysis (FEA) to predict its surface deformation through simulating its working conditions. The surface deformation is also tested and analyzed after machining and mounting. The obtained interferometric data, Zernike coefficients, is written into CODE V, an excellent software for designing optical systems, to analyze the imaging performance of the designed optical system. Through analyzing the deformation of the metal mirror it can be found that the maxima RMS change of the whole optical system is 0.0059λ, which is only 1.52 percent of the designed value. In the full field of view, the RMS error is less than 0.07λ, that means the imaging performance of the whole optical system is close to the diffraction limit.

  9. Self-Calibrating Surface Measuring Machine

    NASA Astrophysics Data System (ADS)

    Greenleaf, Allen H.

    1983-04-01

    A new kind of surface-measuring machine has been developed under government contract at Itek Optical Systems, a Division of Itek Corporation, to assist in the fabrication of large, highly aspheric optical elements. The machine uses four steerable distance-measuring interferometers at the corners of a tetrahedron to measure the positions of a retroreflective target placed at various locations against the surface being measured. Using four interferometers gives redundant information so that, from a set of measurement data, the dimensions of the machine as well as the coordinates of the measurement points can be determined. The machine is, therefore, self-calibrating and does not require a structure made to high accuracy. A wood-structured prototype of this machine was made whose key components are a simple form of air bearing steering mirror, a wide-angle cat's eye retroreflector used as the movable target, and tracking sensors and servos to provide automatic tracking of the cat's eye by the four laser beams. The data are taken and analyzed by computer. The output is given in terms of error relative to an equation of the desired surface. In tests of this machine, measurements of a 0.7 m diameter mirror blank have been made with an accuracy on the order of 0.2µm rms.

  10. Fabrication of an 8:1 ellipsoidal mirror for a synchrotron x-ray microprobe

    SciTech Connect

    Jones, K.W.; Takacs, P.Z.; Hastings, J.B.; Casstevens, J.M.; Pionke, C.D.

    1987-01-11

    The fabrication of an 8:1 demagnifying ellipsoidal mirror to be used for an x-ray microprobe at the National Synchrotron Light Source X-26 beam port is described. The design aim was to produce a mirror that could be used over the photon energy range from about 3 to 17 keV. The 300-mm long mirror was required to operate at a grazing angle of 5 mr. The semimajor axis was 4500 mm and the semiminor axis 14.142 mm. Surface roughness of 1 nm or less and slope errors of 1 arc second parallel to the long axis and 200 arc seconds parallel to the short direction were specified. Production of the first electroless nickel-coated aluminum mirror using a diamond-turning technique has been completed. The mirror meets the 1 arc sec surface figure specification except for areas near the ends of the mirror. The reasons for these deviations arise from subtle details of the diamond-turning process which have not been fully incorporated in to the computer program that controls the diamond-turning machines. Further work in computer correction of repeatable errors of the diamond-turning machine can eliminate the waviness at the ends of the mirror. The diamond-turned mirror surface was not fully polished under this effort and therefore does not meet the roughness specification; however, surface smoothness of a fully polished cylindrical mirror manufactured using the same techniques does not meet the specification. It can be concluded that it is now technically feasible to meet the required specifications for the mirror and that the x-ray microprobe based on its use can be achieved.

  11. Mirror man: a case of skilled deliberate mirror writing.

    PubMed

    McIntosh, Robert D; De Lucia, Natascia; Della Sala, Sergio

    2014-01-01

    Mirror writing is a striking behaviour that is common in children and can reemerge in adults following brain damage. Skilled deliberate mirror writing has also been reported, but only anecdotally. We provide the first quantitative study of skilled deliberate mirror writing. K.B. can write forward or backward, vertically upright or inverted, with the hands acting alone or simultaneously. K.B. is predominantly left handed, but writes habitually with his right hand. Of his writing formats, his left hand mirror writing is by far the most similar in style to his normal handwriting. When writing bimanually, he performs better when his two hands make mirror-symmetrical movements to write opposite scripts than if they move in the same direction to write similar scripts. He has no special facility for reading mirrored text. These features are consistent with prior anecdotal cases and support a motor basis for K.B.'s ability, according to which his skilled mirror writing results from the left hand execution of a low-level motor program for a right hand abductive writing action. Our methods offer a novel framework for investigating the sharing of motor representations across effectors.

  12. The kinaesthetic mirror illusion: How much does the mirror matter?

    PubMed

    Chancel, Marie; Brun, Clémentine; Kavounoudias, Anne; Guerraz, Michel

    2016-06-01

    The reflection of a moving hand in a mirror positioned in the sagittal plane can create an illusion of symmetrical, bimanual movement. This illusion is implicitly presumed to be of visual origin. However, muscle proprioceptive afferents of the arm reflected in the mirror might also affect the perceived position and movement of the other arm. We characterized the relative contributions of visual and proprioceptive cues by performing two experiments. In Experiment 1, we sought to establish whether kinaesthetic illusions induced using the mirror paradigm would survive marked visual impoverishment (obtained by covering between 0 and 100 % of the mirror in 16 % steps). We found that the mirror illusion was only significantly influenced when the visual degradation was 84 % or more. In Experiment 2, we masked the muscle proprioceptive afferents of the arm reflected in the mirror by co-vibrating antagonistic muscles. We found that masking the proprioceptive afferents reduced the velocity of the illusory displacement of the other arm. These results confirm that the mirror illusion is not a purely visual illusion but emerges from a combination of congruent signals from the two arms, i.e. visual afferents from the virtually moving arm and proprioceptive afferents from the contralateral, moving arm.

  13. Point Relay Scanner Utilizing Ellipsoidal Mirrors

    NASA Technical Reports Server (NTRS)

    Manhart, Paul K. (Inventor); Pagano, Robert J. (Inventor)

    1997-01-01

    A scanning system uses a polygonal mirror assembly with each facet of the polygon having an ellipsoidal mirror located thereon. One focal point of each ellipsoidal mirror is located at a common point on the axis of rotation of the polygonal mirror assembly. As the mirror assembly rotates. a second focal point of the ellipsoidal mirrors traces out a scan line. The scanner can be utilized for scanned output display of information or for scanning information to be detected.

  14. Observational physics of mirror world

    NASA Technical Reports Server (NTRS)

    Khlopov, M. YA.; Beskin, G. M.; Bochkarev, N. E.; Pustilnik, L. A.; Pustilnik, S. A.

    1989-01-01

    The existence of the whole world of shadow particles, interacting with each other and having no mutual interactions with ordinary particles except gravity is a specific feature of modern superstring models, being considered as models of the theory of everything. The presence of shadow particles is the necessary condition in the superstring models, providing compensation of the asymmetry of left and right chirality states of ordinary particles. If compactification of additional dimensions retains the symmetry of left and right states, shadow world turns to be the mirror one, with particles and fields having properties strictly symmetrical to the ones of corresponding ordinary particles and fields. Owing to the strict symmetry of physical laws for ordinary and mirror particles, the analysis of cosmological evolution of mirror matter provides rather definite conclusions on possible effects of mirror particles in the universe. A general qualitative discussion of possible astronomical impact of mirror matter is given, in order to make as wide as possible astronomical observational searches for the effects of mirror world, being the unique way to test the existence of mirror partners of ordinary particles in the Nature.

  15. Advanced Mirror & Modelling Technology Development

    NASA Technical Reports Server (NTRS)

    Effinger, Michael; Stahl, H. Philip; Abplanalp, Laura; Maffett, Steven; Egerman, Robert; Eng, Ron; Arnold, William; Mosier, Gary; Blaurock, Carl

    2014-01-01

    The 2020 Decadal technology survey is starting in 2018. Technology on the shelf at that time will help guide selection to future low risk and low cost missions. The Advanced Mirror Technology Development (AMTD) team has identified development priorities based on science goals and engineering requirements for Ultraviolet Optical near-Infrared (UVOIR) missions in order to contribute to the selection process. One key development identified was lightweight mirror fabrication and testing. A monolithic, stacked, deep core mirror was fused and replicated twice to achieve the desired radius of curvature. It was subsequently successfully polished and tested. A recently awarded second phase to the AMTD project will develop larger mirrors to demonstrate the lateral scaling of the deep core mirror technology. Another key development was rapid modeling for the mirror. One model focused on generating optical and structural model results in minutes instead of months. Many variables could be accounted for regarding the core, face plate and back structure details. A portion of a spacecraft model was also developed. The spacecraft model incorporated direct integration to transform optical path difference to Point Spread Function (PSF) and between PSF to modulation transfer function. The second phase to the project will take the results of the rapid mirror modeler and integrate them into the rapid spacecraft modeler.

  16. LSST primary/tertiary monolithic mirror

    NASA Astrophysics Data System (ADS)

    Sebag, J.; Gressler, W.; Liang, M.; Neill, D.; Araujo-Hauck, C.; Andrew, J.; Angeli, G.; Cho, M.; Claver, C.; Daruich, F.; Gessner, C.; Hileman, E.; Krabbendam, V.; Muller, G.; Poczulp, G.; Repp, R.; Wiecha, O.; Xin, B.; Kenagy, K.; Martin, H. M.; Tuell, M. T.; West, S. C.

    2016-08-01

    At the core of the Large Synoptic Survey Telescope (LSST) three-mirror optical design is the primary/tertiary (M1M3) mirror that combines these two large mirrors onto one monolithic substrate. The M1M3 mirror was spin cast and polished at the Steward Observatory Mirror Lab at The University of Arizona (formerly SOML, now the Richard F. Caris Mirror Lab at the University of Arizona (RFCML)). Final acceptance of the mirror occurred during the year 2015 and the mirror is now in storage while the mirror cell assembly is being fabricated. The M1M3 mirror will be tested at RFCML after integration with its mirror cell before being shipped to Chile.

  17. Evanescent Wave Atomic Mirror

    NASA Astrophysics Data System (ADS)

    Ghezali, S.; Taleb, A.

    2008-09-01

    A research project at the "Laboratoire d'électronique quantique" consists in a theoretical study of the reflection and diffraction phenomena via an atomic mirror. This poster presents the principle of an atomic mirror. Many groups in the world have constructed this type of atom optics experiments such as in Paris-Orsay-Villetaneuse (France), Stanford-Gaithersburg (USA), Munich-Heidelberg (Germany), etc. A laser beam goes into a prism with an incidence bigger than the critical incidence. It undergoes a total reflection on the plane face of the prism and then exits. The transmitted resulting wave out of the prism is evanescent and repulsive as the frequency detuning of the laser beam compared to the atomic transition δ = ωL-ω0 is positive. The cold atomic sample interacts with this evanescent wave and undergoes one or more elastic bounces by passing into backward points in its trajectory because the atoms' kinetic energy (of the order of the μeV) is less than the maximum of the dipolar potential barrier ℏΩ2/Δ where Ω is the Rabi frequency [1]. In fact, the atoms are cooled and captured in a magneto-optical trap placed at a distance of the order of the cm above the prism surface. The dipolar potential with which interact the slow atoms is obtained for a two level atom in a case of a dipolar electric transition (D2 Rubidium transition at a wavelength of 780nm delivered by a Titane-Saphir laser between a fundamental state Jf = l/2 and an excited state Je = 3/2). This potential is corrected by an attractive Van der Waals term which varies as 1/z3 in the Lennard-Jones approximation (typical atomic distance of the order of λ0/2π where λ0 is the laser wavelength) and in 1/z4 if the distance between the atom and its image in the dielectric is big in front of λ0/2π. This last case is obtained in a quantum electrodynamic calculation by taking into account an orthornormal base [2]. We'll examine the role of spontaneous emission for which the rate is inversely

  18. Workout Machine

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Orbotron is a tri-axle exercise machine patterned after a NASA training simulator for astronaut orientation in the microgravity of space. It has three orbiting rings corresponding to roll, pitch and yaw. The user is in the middle of the inner ring with the stomach remaining in the center of all axes, eliminating dizziness. Human power starts the rings spinning, unlike the NASA air-powered system. Marketed by Fantasy Factory (formerly Orbotron, Inc.), the machine can improve aerobic capacity, strength and endurance in five to seven minute workouts.

  19. Production of Near-Mirror Surface Quality by Precision Grinding

    NASA Technical Reports Server (NTRS)

    Dimofte, Florin; Krantz, Timothy

    2003-01-01

    Mechanical components such as gears and bearings operate with the working surfaces in intimate contact with a mating part. The performance of such components will be influenced by the quality of the working surface. In general, a smoother surface will perform better than a rougher surface since the lubrication conditions are improved. For example, surfaces with a special near-mirror quality finish of low roughness performed better than ground surfaces when tested using a block-on-ring arrangement. Bearings with near-mirror quality have been tested and analyzed; lower running torques were measured and improved fatigue life was anticipated. Experiments have been done to evaluate the performance of gears with improved, low roughness surface finishing. The measured performance improvements include an increased scuffing (scoring) load capacity by a factor of 1.6, a 30-percent reduction of gear tooth running friction, and longer fatigue lives by a factor of about four. One can also anticipate that near-mirror quality surface finishing could improve the performance of other mechanical components such as mechanical seals and heavily loaded journal bearings. Given these demonstrated benefits, capable and economical methods for the production of mechanical components with near-mirror quality surfaces are desired. One could propose the production of near-mirror quality surfaces by several methods such as abrasive polishing, chemical assisted polishing, or grinding. Production of the surfaces by grinding offers the possibility to control the macro-geometry (form), waviness, and surface texture with one process. The present study was carried out to investigate the possibility of producing near-mirror quality surfaces by grinding. The present study makes use of a specially designed grinding machine spindle to improve the surface quality relative to the quality produced when using a spindle of conventional design.

  20. Wacky Machines

    ERIC Educational Resources Information Center

    Fendrich, Jean

    2002-01-01

    Collectors everywhere know that local antique shops and flea markets are treasure troves just waiting to be plundered. Science teachers might take a hint from these hobbyists, for the next community yard sale might be a repository of old, quirky items that are just the things to get students thinking about simple machines. By introducing some…

  1. The magic of relay mirrors

    NASA Astrophysics Data System (ADS)

    Duff, Edward A.; Washburn, Donald C.

    2004-09-01

    Laser weapon systems would be significantly enhanced with the addition of high altitude or space-borne relay mirrors. Such mirrors, operating alone with a directed energy source, or many in a series fashion, can be shown to effectively move the laser source to the last, so-called fighting mirror. This "magically" reduces the range to target and offers to enhance the performance of directed energy systems like the Airborne Laser and even ground-based or ship-based lasers. Recent development of high altitude airships will be shown to provide stationary positions for such relay mirrors thereby enabling many new and important applications for laser weapons. The technical challenges to achieve this capability are discussed.

  2. JWST Primary Mirror Installation Complete

    NASA Video Gallery

    Completing the assembly of the primary mirror, which took place at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is a significant milestone and the culmination of over a decade of desi...

  3. JWST Secondary Mirror Deploy Timelapse

    NASA Video Gallery

    Setting up NASA's James Webb Space Telescope's secondary mirror in space will require special arms that resemble a tripod that was recently demonstrated in a NASA cleanroom. TRT: 1:25 / Credit: NAS...

  4. Characterizing plasma mirrors near breakdown.

    PubMed

    Geissel, Matthias; Schollmeier, Marius S; Kimmel, Mark W; Rambo, Patrick K; Schwarz, Jens; Atherton, Briggs W; Brambrink, Erik

    2011-05-01

    Experiments dedicated to the characterization of plasma mirrors with a high energy, single shot short-pulse laser were performed at the 100 TW target area of the Z-Backlighter Facility at Sandia National Laboratories. A suite of beam diagnostics was used to characterize a high energy laser pulse with a large aperture through focus imaging setup. By varying the fluence on the plasma mirror around the plasma ignition threshold, critical performance parameters were determined and a more detailed understanding of the way in which a plasma mirror works could be deduced. It was found, that very subtle variations in the laser near field profile will have strong effects on the reflected pulse if the maximum fluence on the plasma mirror approaches the plasma ignition threshold.

  5. Morphing of Segmented Bimorph Mirrors

    NASA Astrophysics Data System (ADS)

    Rodrigues, Gonçalo; Bastaits, Renaud; Preumont, André

    2010-08-01

    Atmospheric turbulence compensation for the next generation of terrestrial telescopes (30-40 m diameter) will require deformable mirrors of increasing size and a number of actuators reaching several thousands. However, the mere extrapolation of existing designs leads to complicated and extremely expensive mirrors. This article discusses an alternative solution based on the use of segmented identical hexagonal bimorph mirrors. This allows to indefinitely increase the degree of correction while maintaining the first mechanical resonance at the level of a single segment, and shows an increase in price only proportional to the number of segments. Extensive simulations using random turbulent screens show that the segmentation produces only moderate reductions of the Strehl number, compared to a monolithic bimorph mirror with the same number of actuators (S = 0.86 instead of S = 0.89 in this study).

  6. Design considerations for mirror materials

    NASA Astrophysics Data System (ADS)

    Gulati, Suresh T.

    1996-11-01

    The key requirements for an optical mirror material include low density, high Young's modulus, low coefficient of thermal expansion, high thermal conductivity, and high diffusivity. Not included among these are fracture toughness and stress corrosion constant, which control slow crack growth and long-term reliability under static or dynamic loads during manufacturing and in-service. The reliability requirement becomes crucial as the mirror size increases and/or its mission takes on strategic importance. This paper compares the critical properties of three ultralow expansion materials, namely ULETM, Zerodur and AstrositallTM. It demonstrates how these properties affect the bending rigidity and safe allowable stress for the mirror subjected to different types of loading, namely: (i) its own weight and (ii) external load. An analysis of bending rigidity, bending stress, and safe allowable stress shows that mirror blanks of two different materials can be designed to be equivalent in terms of their rigidity without any weight penalty. The lower modulus and lightweight material like ULE glass requires about 10 percent higher thickness which reduces the bending stresses 20 percent compared to those in Zerodur or Astrositall mirrors of identical size. The lower stress, according to Power law fatigue model, is highly beneficial in that it improves the mechanical reliability of ULE mirror during manufacturing, transportation, installation and in-service by two orders of magnitude over that of Zerodur and Astrositall mirrors. The fatigue and fracture data for the three materials are used to estimate the safe allowable stress for facilitating mirror design from mechanical reliability point of view.

  7. High temperature current mirror amplifier

    DOEpatents

    Patterson, III, Raymond B.

    1984-05-22

    A high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg.

  8. Torque-while-turnaround scan mirror assembly

    NASA Technical Reports Server (NTRS)

    Starkus, C. J.

    1977-01-01

    A scan mirror assembly which is part of a thematic mapper system is described with emphasis on mechanical aspects of the design. Features of the oscillating scan mirror mechanism include: a low level of structural vibration for the impact energies involved in mirror oscillation and return of energy lost during impact to the mirror by applying torque during the instant of impact.

  9. EAGLE: relay mirror technology development

    NASA Astrophysics Data System (ADS)

    Hartman, Mary; Restaino, Sergio R.; Baker, Jeffrey T.; Payne, Don M.; Bukley, Jerry W.

    2002-06-01

    EAGLE (Evolutionary Air & Space Global Laser Engagement) is the proposed high power weapon system with a high power laser source, a relay mirror constellation, and the necessary ground and communications links. The relay mirror itself will be a satellite composed of two optically-coupled telescopes/mirrors used to redirect laser energy from ground, air, or space based laser sources to distant points on the earth or space. The receiver telescope captures the incoming energy, relays it through an optical system that cleans up the beam, then a separate transmitter telescope/mirror redirects the laser energy at the desired target. Not only is it a key component in extending the range of DoD's current laser weapon systems, it also enables ancillary missions. Furthermore, if the vacuum of space is utilized, then the atmospheric effects on the laser beam propagation will be greatly attenuated. Finally, several critical technologies are being developed to make the EAGLE/Relay Mirror concept a reality, and the Relay Mirror Technology Development Program was set up to address them. This paper will discuss each critical technology, the current state of the work, and the future implications of this program.

  10. Foil X-ray Mirrors

    NASA Astrophysics Data System (ADS)

    Serlemitsos, Peter J.; Soong, Yang

    1996-09-01

    Nested thin foil reflectors have made possible light weight, inexpensive and fast grazing incidence X-ray mirrors for astronomical spectroscopy over a broad band. These mirrors were developed at Goddard for the US Shuttle program and were flown on NASA's shuttleborne Astro-l mission in December 1990. Presently, the Japan/US collaborative spectroscopic mission ASCA, nearing its third year of successful operation in earth orbit, carries, four such mirrors, weighing less than 40 kg and giving total effective areas of ˜ 1200 and 420 cm2 at l and 8 keV respectively. The ˜ 420 kg observatory is the best possible example of how conical foil mirrors opened areas of research that could not have been otherwise addressed with available resources. In this paper, we will briefly review the development and performance of our first generation foil mirrors. We will also describe progress toward improving their imaging capability to prime them for use in future instruments. Such a goal is highly desirable, if not necessary for this mirror technology to remain competitive for future applications.

  11. QED with a spherical mirror

    SciTech Connect

    Hetet, G.; Blatt, R.; Slodicka, L.; Hennrich, M.; Glaetzle, A.

    2010-12-15

    We investigate the quantum electrodynamic (QED) properties of an atomic electron close to the focus of a spherical mirror. We first show that the spontaneous emission and excited-state level shift of the atom can be fully suppressed with mirror-atom distances of many wavelengths. A three-dimensional theory predicts that the spectral density of vacuum fluctuations can indeed vanish within a volume {lambda}{sup 3} around the atom, with the use of a far-distant mirror covering only half of the atomic emission solid angle. The modification of these QED atomic properties is also computed as a function of the mirror size, and large effects are found for only moderate numerical apertures. We also evaluate the long-distance ground-state energy shift (Casimir-Polder shift) and find that it scales as ({lambda}/R){sup 2} at the focus of a hemispherical mirror of radius R, as opposed to the well-known ({lambda}/R){sup 4} scaling law for an atom at a distance R from an infinite plane mirror. Our results are relevant for investigations of QED effects as well as free-space coupling to single atoms using high-numerical-aperture lenses.

  12. High stroke pixel for a deformable mirror

    DOEpatents

    Miles, Robin R.; Papavasiliou, Alexandros P.

    2005-09-20

    A mirror pixel that can be fabricated using standard MEMS methods for a deformable mirror. The pixel is electrostatically actuated and is capable of the high deflections needed for spaced-based mirror applications. In one embodiment, the mirror comprises three layers, a top or mirror layer, a middle layer which consists of flexures, and a comb drive layer, with the flexures of the middle layer attached to the mirror layer and to the comb drive layer. The comb drives are attached to a frame via spring flexures. A number of these mirror pixels can be used to construct a large mirror assembly. The actuator for the mirror pixel may be configured as a crenellated beam with one end fixedly secured, or configured as a scissor jack. The mirror pixels may be used in various applications requiring high stroke adaptive optics.

  13. Status of mirror segment production for the Giant Magellan Telescope

    NASA Astrophysics Data System (ADS)

    Martin, H. M.; Burge, J. H.; Davis, J. M.; Kim, D. W.; Kingsley, J. S.; Law, K.; Loeff, A.; Lutz, R. D.; Merrill, C.; Strittmatter, P. A.; Tuell, M. T.; Weinberger, S. N.; West, S. C.

    2016-07-01

    The Richard F. Caris Mirror Lab at the University of Arizona is responsible for production of the eight 8.4 m segments for the primary mirror of the Giant Magellan Telescope, including one spare off-axis segment. We report on the successful casting of Segment 4, the center segment. Prior to generating the optical surface of Segment 2, we carried out a major upgrade of our 8.4 m Large Optical Generator. The upgrade includes new hardware and software to improve accuracy, safety, reliability and ease of use. We are currently carrying out an upgrade of our 8.4 m polishing machine that includes improved orbital polishing capabilities. We added and modified several components of the optical tests during the manufacture of Segment 1, and we have continued to improve the systems in preparation for Segments 2-8. We completed two projects that were prior commitments before GMT Segment 2: casting and polishing the combined primary and tertiary mirrors for the LSST, and casting and generating a 6.5 m mirror for the Tokyo Atacama Observatory.

  14. Machine Learning

    NASA Astrophysics Data System (ADS)

    Hoffmann, Achim; Mahidadia, Ashesh

    The purpose of this chapter is to present fundamental ideas and techniques of machine learning suitable for the field of this book, i.e., for automated scientific discovery. The chapter focuses on those symbolic machine learning methods, which produce results that are suitable to be interpreted and understood by humans. This is particularly important in the context of automated scientific discovery as the scientific theories to be produced by machines are usually meant to be interpreted by humans. This chapter contains some of the most influential ideas and concepts in machine learning research to give the reader a basic insight into the field. After the introduction in Sect. 1, general ideas of how learning problems can be framed are given in Sect. 2. The section provides useful perspectives to better understand what learning algorithms actually do. Section 3 presents the Version space model which is an early learning algorithm as well as a conceptual framework, that provides important insight into the general mechanisms behind most learning algorithms. In section 4, a family of learning algorithms, the AQ family for learning classification rules is presented. The AQ family belongs to the early approaches in machine learning. The next, Sect. 5 presents the basic principles of decision tree learners. Decision tree learners belong to the most influential class of inductive learning algorithms today. Finally, a more recent group of learning systems are presented in Sect. 6, which learn relational concepts within the framework of logic programming. This is a particularly interesting group of learning systems since the framework allows also to incorporate background knowledge which may assist in generalisation. Section 7 discusses Association Rules - a technique that comes from the related field of Data mining. Section 8 presents the basic idea of the Naive Bayesian Classifier. While this is a very popular learning technique, the learning result is not well suited for

  15. Lightweight C/SiC mirrors for space application

    NASA Astrophysics Data System (ADS)

    Zhou, Hao; Zhang, Chang-rui; Cao, Ying-bin; Zhou, Xin-gui

    2006-02-01

    Challenges in high resolution space telescopes have led to the desire to create large primary mirror apertures. Ceramic mirrors and complex structures are becoming more important for high precision lightweight optical applications in adverse environments. Carbon-fiber reinforced silicon carbide (C/SiC) has shown great potential to be used as mirror substrate. This material has a high stiffness to weight ratio, dimensional stability from ambient to cryo temperatures, and thermal conductivity, low thermal expansion as well. These properties make C/SiC very attractive for a variety of applications in precision optical structures, especially when considering space-borne application. In this paper, lightweight C/SiC mirror prepared for a scan mirror of a high resolution camera is presented. The manufacturing of C/SiC mirror starts with a porous rigid felt made of short chopped carbon fibers. The fibers are molded with phenolic resin under pressure to form a carbon fiber reinforced plastic blank, followed by a pyrolization process by which the phenolic resin reacts to a carbon matrix. The C/C-felt can be machined by standard computer controlled milling techniques to any virtual shape. This is one of the most significant advantages of this material, as it drastically reduces the making costs and enables the manufacture of truly ultra-lightweight mirrors, reflectors and structures. Upon completion of milling, the C/C-felt preform is mounted in a high-temperature furnace together with silicon and heated under vacuum condition to 1500°C at which the silicon changes into liquid phase. Subsequently, the molten silicon is infiltrated into the porous preform under capillary forces to react with carbon matrix and the surfaces of the carbon fibers to form a density C/SiC substrate. The C/SiC material retains the preform shape to within a tight tolerance after sintering means the ceramization process is a nearly net shaping process. Reactive melt infiltrated C/SiC, followed by

  16. Displacement sensor for indoor machine calibrations.

    PubMed

    Mudassar, Asloob Ahmad; Butt, Saira

    2013-05-20

    This paper presents a simple displacement sensor for indoor machine calibrations. The sensor, which is placed in the path of a diverging laser beam, consists of two plane mirror pieces laterally displaced with the line joining their centers initially held perpendicular to the optical axis of the beam during the displacement of the sensor with one of the mirrors always traveling along the optical axis of the laser beam. The optical signals from the two mirrors are combined and a simple detector at the interference plane counts the fringes during the sensor displacement. The sensor could be mounted on the moving head of any mechanical machine, e.g., the lathe machine for displacement calibration. The device has been tested over a range of 10 cm beyond a distance of 150 cm from a diverging laser source giving an accuracy of 1.1015 μm. Theoretical modeling, simulation, and experimental results are presented which establish that the proposed sensor can be used as a promising displacement measuring device.

  17. Scalable stacked array piezoelectric deformable mirror for astronomy and laser processing applications

    SciTech Connect

    Wlodarczyk, Krystian L. Maier, Robert R. J.; Hand, Duncan P.; Bryce, Emma; Hutson, David; Kirk, Katherine; Schwartz, Noah; Atkinson, David; Beard, Steven; Baillie, Tom; Parr-Burman, Phil; Strachan, Mel

    2014-02-15

    A prototype of a scalable and potentially low-cost stacked array piezoelectric deformable mirror (SA-PDM) with 35 active elements is presented in this paper. This prototype is characterized by a 2 μm maximum actuator stroke, a 1.4 μm mirror sag (measured for a 14 mm × 14 mm area of the unpowered SA-PDM), and a ±200 nm hysteresis error. The initial proof of concept experiments described here show that this mirror can be successfully used for shaping a high power laser beam in order to improve laser machining performance. Various beam shapes have been obtained with the SA-PDM and examples of laser machining with the shaped beams are presented.

  18. Scalable stacked array piezoelectric deformable mirror for astronomy and laser processing applications.

    PubMed

    Wlodarczyk, Krystian L; Bryce, Emma; Schwartz, Noah; Strachan, Mel; Hutson, David; Maier, Robert R J; Atkinson, David; Beard, Steven; Baillie, Tom; Parr-Burman, Phil; Kirk, Katherine; Hand, Duncan P

    2014-02-01

    A prototype of a scalable and potentially low-cost stacked array piezoelectric deformable mirror (SA-PDM) with 35 active elements is presented in this paper. This prototype is characterized by a 2 μm maximum actuator stroke, a 1.4 μm mirror sag (measured for a 14 mm × 14 mm area of the unpowered SA-PDM), and a ±200 nm hysteresis error. The initial proof of concept experiments described here show that this mirror can be successfully used for shaping a high power laser beam in order to improve laser machining performance. Various beam shapes have been obtained with the SA-PDM and examples of laser machining with the shaped beams are presented.

  19. Charging machine

    DOEpatents

    Medlin, John B.

    1976-05-25

    A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine.

  20. Induction machine

    DOEpatents

    Owen, Whitney H.

    1980-01-01

    A polyphase rotary induction machine for use as a motor or generator utilizing a single rotor assembly having two series connected sets of rotor windings, a first stator winding disposed around the first rotor winding and means for controlling the current induced in one set of the rotor windings compared to the current induced in the other set of the rotor windings. The rotor windings may be wound rotor windings or squirrel cage windings.

  1. Machine vision

    SciTech Connect

    Horn, D.

    1989-06-01

    To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human learning patterns. These networks and their hardware implementations (neurocomputers) show a great deal of promise for machine vision systems because they allow the systems to understand the use sensory data input more effectively. Neurocomputers excel at pattern-recognition tasks when input data are fuzzy or the vision algorithm is not optimal and is difficult to ascertain.

  2. Metamaterial mirrors in optoelectronic devices.

    PubMed

    Esfandyarpour, Majid; Garnett, Erik C; Cui, Yi; McGehee, Michael D; Brongersma, Mark L

    2014-07-01

    The phase reversal that occurs when light is reflected from a metallic mirror produces a standing wave with reduced intensity near the reflective surface. This effect is highly undesirable in optoelectronic devices that use metal films as both electrical contacts and optical mirrors, because it dictates a minimum spacing between the metal and the underlying active semiconductor layers, therefore posing a fundamental limit to the overall thickness of the device. Here, we show that this challenge can be circumvented by using a metamaterial mirror whose reflection phase is tunable from that of a perfect electric mirror (φ = π) to that of a perfect magnetic mirror (φ = 0). This tunability in reflection phase can also be exploited to optimize the standing wave profile in planar devices to maximize light-matter interaction. Specifically, we show that light absorption and photocurrent generation in a sub-100 nm active semiconductor layer of a model solar cell can be enhanced by ∼20% over a broad spectral band.

  3. Compact neutron imaging system using axisymmetric mirrors

    SciTech Connect

    Khaykovich, Boris; Moncton, David E; Gubarev, Mikhail V; Ramsey, Brian D; Engelhaupt, Darell E

    2014-05-27

    A dispersed release of neutrons is generated from a source. A portion of this dispersed neutron release is reflected by surfaces of a plurality of nested, axisymmetric mirrors in at least an inner mirror layer and an outer mirror layer, wherein the neutrons reflected by the inner mirror layer are incident on at least one mirror surface of the inner mirror layer N times, wherein N is an integer, and wherein neutrons reflected by the outer mirror are incident on a plurality of mirror surfaces of the outer layer N+i times, where i is a positive integer, to redirect the neutrons toward a target. The mirrors can be formed by a periodically reversed pulsed-plating process.

  4. Development of Individually Addressable Micro-Mirror-Arrays for Space Applications

    NASA Technical Reports Server (NTRS)

    Dutta, Sanghamitra B.; Ewin, Audrey J.; Jhabvala, Murzy; Kotecki, Carl A.; Kuhn, Jonathan L.; Mott, D. Brent

    2000-01-01

    We have been developing a 32 x 32 prototype array of individually addressable Micro-Mirrors capable of operating at cryogenic temperature for Earth and Space Science applications. Micro-Mirror-Array technology has the potential to revolutionize imaging and spectroscopy systems for NASA's missions of the 21st century. They can be used as programmable slits for the Next Generation Space Telescope, as smart sensors for a steerable spectrometer, as neutral density filters for bright scene attenuation etc. The, entire fabrication process is carried out in the Detector Development Laboratory at NASA, GSFC. The fabrication process is low temperature compatible and involves integration of conventional CMOS technology and surface micro-machining used in MEMS. Aluminum is used as the mirror material and is built on a silicon substrate containing the CMOS address circuit. The mirrors are 100 microns x l00 microns in area and deflect by +/- 10 deg induced by electrostatic actuation between two parallel plate capacitors. A pair of thin aluminum torsion straps allow the mirrors to tilt. Finite-element-analysis and closed form solutions using electrostatic and mechanical torque for mirror operation were developed and the results were compared with laboratory performance. The results agree well both at room temperature and at cryogenic temperature. The development demonstrates the first cryogenic operation of two-dimensional Micro-Mirrors with bi-state operation. Larger arrays will be developed meeting requirements for different science applications. Theoretical analysis, fabrication process, laboratory test results and different science applications will be described in detail.

  5. SUPER MIRROR FABRICATION VIA ELECTROFORMING.

    SciTech Connect

    ULMER,M.P.; ALTKORN,R.; KRIEGER,A.; PARSIGNAULT,D.; CHUNG,Y.W.; WONG,M.S.; LAI,B.; MANCINI,D.; TAKACS,P.Z.; CHURCH,E.

    1997-07-27

    As part of a project to develop methods of placing highly reflective multilayer coatings on the inside of Wolter I mirrors, we have been pursuing a program of measuring flat mirrors. These flats have been produced and examined at various stages of the process we plan to use to fabricate multilayer coated Wolter I mirrors. The flats were measured via optical profiler, AFM, (both done at Brookhaven National Lab) and X-ray reflection (done at the Argonne National Lab (ANL) Advanced Photon Source (APS)). We report for the first time, to our knowledge, the successful placement of multilayers on an electroform by depositing the multilayers on a master and then electroforming onto this master and removing the multilayers, intact, on the electroform. This process is the one we plan to use to place multilayers on the inside of Wolter I optics.

  6. Metrology of IXO Mirror Segments

    NASA Technical Reports Server (NTRS)

    Chan, Kai-Wing

    2011-01-01

    For future x-ray astrophysics mission that demands optics with large throughput and excellent angular resolution, many telescope concepts build around assembling thin mirror segments in a Wolter I geometry, such as that originally proposed for the International X-ray Observatory. The arc-second resolution requirement posts unique challenges not just for fabrication, mounting but also for metrology of these mirror segments. In this paper, we shall discuss the metrology of these segments using normal incidence metrological method with interferometers and null lenses. We present results of the calibration of the metrology systems we are currently using, discuss their accuracy and address the precision in measuring near-cylindrical mirror segments and the stability of the measurements.

  7. First Giant Mirror for the ESO VLT Ready at REOSC

    NASA Astrophysics Data System (ADS)

    1995-11-01

    The REOSC Contract In 1989, the European Southern Observatory (ESO), the European Organisation for Astronomy, awarded to REOSC, a subsidiary of the SFIM Group and located in Saint Pierre du Perray (France), a comprehensive contract for the polishing of four 8.2-metre diameter mirrors for the unit telescopes of the ESO Very Large Telescope (VLT) project. These mirrors are the largest ever manufactured and polished. This contract comprises not only the polishing and high-precision optical testing of each giant mirror, but also the safe condition of transportation of the blanks which were manufactured by Schott Glaswerke in Mainz (Germany). In order to fulfill the contract, REOSC conceived, built and equipped a novel, high-tech workshop which would allow to polish and test the mirrors, each of which has a surface area of more than 50 square metres. First 8.2-Metre Mirror is Ready and within Specifications The REOSC polishing facility for giant mirrors was built in Saint Pierre du Perray, just south of Paris. It is equipped with two machines: one for grinding and the other for polishing the mirrors, and both with 150-actuator systems that support the thin and flexible mirrors. All equipment is computer controlled. State-of-the-art interferometers probe the accuracy of the mirror surface as the polishing proceeds; they are installed at the top level of the facility in a 30-metre high tower, at the centre of the mirror's radius of curvature. The success of the work at REOSC is now evident by the fact that careful measurements of the first mirror earlier this month have shown that the final optical surface is correct to within 0.00005 millimetres. For illustration, this corresponds to an accuracy of only 1 millimetre deviation over a surface with a diameter of 165 kilometres (equivalent to the entire Paris area)! ESO Receives the First VLT Mirror After having been carefully placed in a special transport box designed by REOSC, the first mirror blank, weighing 23.5 tons and

  8. Fokker-Planck equation in mirror research

    SciTech Connect

    Post, R.F.

    1983-08-11

    Open confinement systems based on the magnetic mirror principle depend on the maintenance of particle distributions that may deviate substantially from Maxwellian distributions. Mirror research has therefore from the beginning relied on theoretical predictions of non-equilibrium rate processes obtained from solutions to the Fokker-Planck equation. The F-P equation plays three roles: Design of experiments, creation of classical standards against which to compare experiment, and predictions concerning mirror based fusion power systems. Analytical and computational approaches to solving the F-P equation for mirror systems will be reviewed, together with results and examples that apply to specific mirror systems, such as the tandem mirror.

  9. Fused silica mirror development for SIRTF

    NASA Technical Reports Server (NTRS)

    Barnes, W. P., Jr.

    1983-01-01

    An advanced design, lightweight, fuse-quartz mirror of sandwich construction was evaluated for optical figure performance at cryogenic temperatures. A low temperature shroud was constructed with an integral mirror mount and interface to a cryostat for use in a vacuum chamber. The mirror was tested to 13 K. Cryogenic distortion of the mirror was measured interferometrically. Separate interferometry of the chamber window during the test permitted subtraction of the small window distortions from the data. Results indicate that the imaging performance of helium cooled, infrared telescopes will be improved using this type of mirror without correction of cryogenic distortion of the primary mirror.

  10. Strength of Zerodur® for mirror applications

    NASA Astrophysics Data System (ADS)

    Béhar-Lafenêtre, S.; Cornillon, Laurence; Ait-Zaid, Sonia

    2015-09-01

    Zerodur® is a well-known glass-ceramic used for optical components because of its unequalled dimensional stability under thermal environment. In particular it has been used since decades in Thales Alenia Space's optical payloads for space telescopes, especially for mirrors. The drawback of Zerodur® is however its quite low strength, but the relatively small size of mirrors in the past had made it unnecessary to further investigate this aspect, although elementary tests have always shown higher failure strength. As performance of space telescopes is increasing, the size of mirrors increases accordingly, and an optimization of the design is necessary, mainly for mass saving. Therefore the question of the effective strength of Zerodur® has become a real issue. Thales Alenia Space has investigated the application of the Weibull law and associated size effects on Zerodur® in 2014, under CNES funding, through a thorough test campaign with a high number of samples (300) of various types. The purpose was to accurately determine the parameters of the Weibull law for Zerodur® when machined in the same conditions as mirrors. The proposed paper will discuss the obtained results, in the light of the Weibull theory. The applicability of the 2-parameter and 3-parameter (with threshold strength) laws will be compared. The expected size effect has not been evidenced therefore some investigations are led to determine the reasons of this result, from the test implementation quality to the data post-processing methodology. However this test campaign has already provided enough data to safely increase the allowable value for mirrors sizing.

  11. TEMPO machine

    SciTech Connect

    Rohwein, G.J.; Lancaster, K.T.; Lawson, R.N.

    1986-06-01

    TEMPO is a transformer powered megavolt pulse generator with an output pulse of 100 ns duration. The machine was designed for burst mode operation at pulse repetition rates up to 10 Hz with minimum pulse-to-pulse voltage variations. To meet the requirement for pulse duration a nd a 20-..omega.. output impedance within reasonable size constraints, the pulse forming transmission line was designed as two parallel water-insulated, strip-type Blumleins. Stray capacitance and electric fields along the edges of the line elements were controlled by lining the tank with plastic sheet.

  12. Tandem Mirror Experiment Upgrade (TMX-U) overview-recent events

    SciTech Connect

    Calderon, M.O.; Bell, H.H.

    1985-11-14

    Since its construction and commissioning was completed in the winter of 1981, the Tandem Mirror Experiment Upgrade (TMX-U) has been conducting tandem mirror thermal barrier experiments. The work, following the fall of 1983 when strong plugging with thermal barriers was achieved, has been directed toward controlling radial transport and forming thermal barriers with high density and Beta. This paper describes the overall engineering component of these efforts. Major changes to the machine have included vacuum improvements, changes to the Electron and Ion Cyclotron Resonance Heating systems (ECRH and ICRH), and the installation of a Plasma Potential Control system (PPC) for radial transport reduction. TMX-U operates an extensive diagnostics system that acquires data from 21 types of diagnostic instruments with more than 600 channels, in addition to 246 machine parameters. The changes and additions will be presented. The closing section of this paper will describe the initial study work for a proposed TMX-U octupole configured machine.

  13. Compaction managed mirror bend achromat

    DOEpatents

    Douglas, David

    2005-10-18

    A method for controlling the momentum compaction in a beam of charged particles. The method includes a compaction-managed mirror bend achromat (CMMBA) that provides a beamline design that retains the large momentum acceptance of a conventional mirror bend achromat. The CMMBA also provides the ability to tailor the system momentum compaction spectrum as desired for specific applications. The CMMBA enables magnetostatic management of the longitudinal phase space in Energy Recovery Linacs (ERLs) thereby alleviating the need for harmonic linearization of the RF waveform.

  14. Controllable objective with deformable mirrors

    SciTech Connect

    Agafonov, V V; Safronov, A G

    2004-03-31

    A new optical device - an objective with deformable mirrors and parameters controlled in the dynamic regime is proposed. The computer simulation of the objective is performed. The dependences of some parameters of the objective on the control voltage are determined. The simulation showed that the ranges of control of the rear focal segment and the focal distance for the objective with the focal distance 602 mm were 1057 and 340 mm, respectively, which is substantially greater than in the control of an equivalent deformable mirror. (laser applications and other topics in quantum electronics)

  15. High temperature current mirror amplifier

    DOEpatents

    Patterson, R.B. III.

    1984-05-22

    Disclosed is a high temperature current mirror amplifier having biasing means in the transdiode connection of the input transistor for producing a voltage to maintain the base-collector junction reversed-biased and a current means for maintaining a current through the biasing means at high temperatures so that the base-collector junction of the input transistor remained reversed-biased. For accuracy, a second current mirror is provided with a biasing means and current means on the input leg. 2 figs.

  16. Nonsupersymmetric Dualities from Mirror Symmetry

    NASA Astrophysics Data System (ADS)

    Kachru, Shamit; Mulligan, Michael; Torroba, Gonzalo; Wang, Huajia

    2017-01-01

    We study supersymmetry breaking perturbations of the simplest dual pair of (2 +1 )-dimensional N =2 supersymmetric field theories—the free chiral multiplet and N =2 super QED with a single flavor. We find dual descriptions of a phase diagram containing four distinct massive phases. The equivalence of the intervening critical theories gives rise to several nonsupersymmetric avatars of mirror symmetry: we find dualities relating scalar QED to a free fermion and Wilson-Fisher theories to both scalar and fermionic QED. Thus, mirror symmetry can be viewed as the multicritical parent duality from which these nonsupersymmetric dualities directly descend.

  17. NASA CONNECT: Algebra: Mirror, Mirror on the Universe

    NASA Technical Reports Server (NTRS)

    2000-01-01

    'Algebra: Mirror, Mirror on the Universe' is the last of seven programs in the 1999-2000 NASA CONNECT series. Produced by NASA Langley Research Center's Office of Education, NASA CONNECT is an award-winning series of instructional programs designed to enhance the teaching of math, science and technology concepts in grades 5-8. NASA CONNECT establishes the 'connection' between the mathematics, science, and technology concepts taught in the classroom and NASA research. Each program in the series supports the national mathematics, science, and technology standards; includes a resource-rich teacher guide; and uses a classroom experiment and web-based activity to complement and enhance the math, science, and technology concepts presented in the program. NASA CONNECT is FREE and the programs in the series are in the public domain. Visit our web site and register. http://connect.larc.nasa.gov In 'Algebra: Mirror, Mirror on the Universe', students will learn how algebra is used to explore the universe.

  18. Lightweight ZERODUR: Validation of Mirror Performance and Mirror Modeling Predictions

    NASA Technical Reports Server (NTRS)

    Hull, Tony; Stahl, H. Philip; Westerhoff, Thomas; Valente, Martin; Brooks, Thomas; Eng, Ron

    2017-01-01

    Upcoming spaceborne missions, both moderate and large in scale, require extreme dimensional stability while relying both upon established lightweight mirror materials, and also upon accurate modeling methods to predict performance under varying boundary conditions. We describe tests, recently performed at NASA's XRCF chambers and laboratories in Huntsville Alabama, during which a 1.2 m diameter, f/1.2988% lightweighted SCHOTT lightweighted ZERODUR(TradeMark) mirror was tested for thermal stability under static loads in steps down to 230K. Test results are compared to model predictions, based upon recently published data on ZERODUR(TradeMark). In addition to monitoring the mirror surface for thermal perturbations in XRCF Thermal Vacuum tests, static load gravity deformations have been measured and compared to model predictions. Also the Modal Response(dynamic disturbance) was measured and compared to model. We will discuss the fabrication approach and optomechanical design of the ZERODUR(TradeMark) mirror substrate by SCHOTT, its optical preparation for test by Arizona Optical Systems (AOS). Summarize the outcome of NASA's XRCF tests and model validations

  19. Lightweight ZERODUR®: Validation of mirror performance and mirror modeling predictions

    NASA Astrophysics Data System (ADS)

    Hull, Anthony B.; Stahl, H. Philip; Westerhoff, Thomas; Valente, Martin; Brooks, Thomas; Eng, Ron

    2017-01-01

    Upcoming spaceborne missions, both moderate and large in scale, require extreme dimensional stability while relying both upon established lightweight mirror materials, and also upon accurate modeling methods to predict performance under varying boundary conditions. We describe tests, recently performed at NASA’s XRCF chambers and laboratories in Huntsville Alabama, during which a 1.2m diameter, f/1.29 88% lightweighted SCHOTT lightweighted ZERODUR® mirror was tested for thermal stability under static loads in steps down to 230K. Test results are compared to model predictions, based upon recently published data on ZERODUR®. In addition to monitoring the mirror surface for thermal perturbations in XRCF Thermal Vacuum tests, static load gravity deformations have been measured and compared to model predictions. Also the Modal Response (dynamic disturbance) was measured and compared to model. We will discuss the fabrication approach and optomechanical design of the ZERODUR® mirror substrate by SCHOTT, its optical preparation for test by Arizona Optical Systems (AOS), and summarize the outcome of NASA’s XRCF tests and model validations.

  20. Ultra-high-precision surface processing techniques for nanofocusing ellipsoidal mirrors in hard x-ray region

    NASA Astrophysics Data System (ADS)

    Yumoto, Hirokatsu; Koyama, Takahisa; Matsuyama, Satoshi; Yamauchi, Kazuto; Ohashi, Haruhiko

    2014-09-01

    X-ray microscopic analysis as a fundamental tool in various scientific fields is supported by advancements in highprecision x-ray optics. Off-axis ellipsoidal focusing mirror optics, which can produce two-dimensional focus with a mirror and has characteristics of high reflectivity and achromaticity, is quite attractive for use in microscopic analysis. However, technical problems in fabrication prevent a realization of off-axis ellipsoidal mirrors with nanometer accuracy for nano-focusing of hard x-rays. The purpose of this study was to resolve a problem of surface processing technique for fabrication of nanofocusing ellipsoidal mirrors in the hard x-ray region. We developed two types of ultra-high-precision surface processing machines by advancing the Elastic Emission Machining method. One is a machine for improvement of surface roughness with a rotary type working head, and the other is a machine for a computer-controlled figure correction with a small-aperture nozzle type working head. Using the rotary type machine, we confirmed that surface roughness of 4.32 nm root-mean-square (RMS) on an off-axis ellipsoidal mirror surface was improved to 0.14 nm (RMS) within a spatial wavelength range of shorter than several hundred microns. Using the nozzle type machine, we demonstrated a figure correction in a spatial wavelength of longer than 100 μm with nanometer height accuracy. Ultrahigh- precision surface processing technologies with the capability of fabricating nano-focusing off-axis ellipsoidal mirrors were established.

  1. Timecourse of mirror and counter-mirror effects measured with transcranial magnetic stimulation.

    PubMed

    Cavallo, Andrea; Heyes, Cecilia; Becchio, Cristina; Bird, Geoffrey; Catmur, Caroline

    2014-08-01

    The human mirror system has been the subject of much research over the past two decades, but little is known about the timecourse of mirror responses. In addition, it is unclear whether mirror and counter-mirror effects follow the same timecourse. We used single-pulse transcranial magnetic stimulation to investigate the timecourse of mirror and counter-mirror responses in the human brain. Experiment 1 demonstrated that mirror responses can be measured from around 200 ms after observed action onset. Experiment 2 demonstrated significant effects of counter-mirror sensorimotor training at all timepoints at which a mirror response was found in Experiment 1 (i.e. from 200 ms onward), indicating that mirror and counter-mirror responses follow the same timecourse. By suggesting similarly direct routes for mirror and counter-mirror responses, these results support the associative account of mirror neuron origins whereby mirror responses arise as a result of correlated sensorimotor experience during development. More generally, they contribute to theorizing regarding mirror neuron function by providing some constraints on how quickly mirror responses can influence social cognition.

  2. Parallel machines: Parallel machine languages

    SciTech Connect

    Iannucci, R.A. )

    1990-01-01

    This book presents a framework for understanding the tradeoffs between the conventional view and the dataflow view with the objective of discovering the critical hardware structures which must be present in any scalable, general-purpose parallel computer to effectively tolerate latency and synchronization costs. The author presents an approach to scalable general purpose parallel computation. Linguistic Concerns, Compiling Issues, Intermediate Language Issues, and hardware/technological constraints are presented as a combined approach to architectural Develoement. This book presents the notion of a parallel machine language.

  3. Genetics Home Reference: congenital mirror movement disorder

    MedlinePlus

    ... Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Congenital mirror movement disorder is a condition in which intentional movements of one side of the body are mirrored by involuntary movements ...

  4. Mirror with thermally controlled radius of curvature

    DOEpatents

    Neil, George R.; Shinn, Michelle D.

    2010-06-22

    A radius of curvature controlled mirror for controlling precisely the focal point of a laser beam or other light beam. The radius of curvature controlled mirror provides nearly spherical distortion of the mirror in response to differential expansion between the front and rear surfaces of the mirror. The radius of curvature controlled mirror compensates for changes in other optical components due to heating or other physical changes. The radius of curvature controlled mirror includes an arrangement for adjusting the temperature of the front surface and separately adjusting the temperature of the rear surface to control the radius of curvature. The temperature adjustment arrangements can include cooling channels within the mirror body or convection of a gas upon the surface of the mirror. A control system controls the differential expansion between the front and rear surfaces to achieve the desired radius of curvature.

  5. [The ontogeny of the mirror neuron system].

    PubMed

    Myowa-Yamakoshi, Masako

    2014-06-01

    Abstract Humans utilize the mirror neuron system to understand and predict others' actions. However, the ontogeny of the mirror neuron system remains unknown. Whether mirror neuron function is an innate trait or whether mirror neurons acquire their sensorimotor matching properties ontogenetically remains to be clarified. In this paper, I review the ontogenetic theory of the mirror neuron system. I then discuss the functioning of the mirror neuron system in the context of social cognitive abilities, which are unique to humans. Recently, some researchers argue that it is too early to interpret the function of mirror neurons as an understanding of the underlying psychological states of others. They imply that such functioning would require inferential cognitive processes that are known to involve areas outside the mirror neuron system. Filling in this missing link may be the key to elucidating the unique ability of humans to understand others' actions.

  6. Metallic waveguide mirrors in polymer film waveguides

    NASA Astrophysics Data System (ADS)

    Wolff, S.; Giehl, A. R.; Renno, M.; Fouckhardt, H.

    2001-10-01

    A technology for the fabrication of metallic waveguide mirrors is developed. Plane and curved waveguide mirrors, the latter acting in the same way as cylindrical lenses, are realized in benzocyclobutene (BCB) film waveguides. The waveguide mirror structure is dry-etched into the BCB film waveguide. To enhance the reflectivity of the waveguide mirrors, the waveguide edge is metallized. The BCB film waveguide mirrors are characterized with respect to waveguide attenuation and mirror reflectivity. The waveguide attenuation of the processed BCB waveguide is 0.5 dB/cm. Ag-coated BCB waveguide mirrors show a reflectivity of 71%. The efficiency of total internal reflection (TIR, i.e. in the case without metallization) at the dry-etched waveguide edge is 74%. As an application of the BCB waveguide mirrors a hybrid integrated optical module for Fourier-optical transverse mode selection in broad area lasers (BAL) is proposed.

  7. The "Rear View Mirror" Approach.

    ERIC Educational Resources Information Center

    Nord, James R.

    1987-01-01

    The new interactive videodisk systems with augmented audio capabilities have great potential for improving the teaching of foreign languages. At present that potential is unfulfilled because the profession is following a "rear view mirror" approach to media use: first, to fixate current practice; second, to distribute it broadly; and last, to…

  8. Collodion technique of mirror cleaning

    NASA Technical Reports Server (NTRS)

    Tyndall, J. B.

    1970-01-01

    Cleaning method is modified by addition of a layer of cheesecloth between thin coatings of U.S.P. collodion. After drying, the collodion is peeled off by an even pull on the cheesecloth, leaving the mirror clean and ready for use.

  9. Mounting and Alignment of IXO Mirror Segments

    NASA Technical Reports Server (NTRS)

    Chan, Kai-Wing; Zhang, William; Evans, Tyler; McClelland, Ryan; Hong, Melinda; Mazzarella, James; Saha, Timo; Jalota, Lalit; Olsen, Lawrence; Byron, Glenn

    2010-01-01

    A suspension-mounting scheme is developed for the IXO (International X-ray Observatory) mirror segments in which the figure of the mirror segment is preserved in each stage of mounting. The mirror, first fixed on a thermally compatible strongback, is subsequently transported, aligned and transferred onto its mirror housing. In this paper, we shall outline the requirement, approaches, and recent progress of the suspension mount processes.

  10. The Axisymmetric Tandem Mirror: A Magnetic Mirror Concept Game Changer Magnet Mirror Status Study Group

    SciTech Connect

    Simonen, T; Cohen, R; Correll, D; Fowler, K; Post, D; Berk, H; Horton, W; Hooper, E B; Fisch, N; Hassam, A; Baldwin, D; Pearlstein, D; Logan, G; Turner, B; Moir, R; Molvik, A; Ryutov, D; Ivanov, A A; Kesner, J; Cohen, B; McLean, H; Tamano, T; Tang, X Z; Imai, T

    2008-10-24

    Experimental results, theory and innovative ideas now point with increased confidence to the possibility of a Gas Dynamic Trap (GDT) neutron source which would be on the path to an attractively simple Axisymmetric Tandem Mirror (ATM) power plant. Although magnetic mirror research was terminated in the US 20 years ago, experiments continued in Japan (Gamma 10) and Russia (GDT), with a very small US effort. This research has now yielded data, increased understanding, and generated ideas resulting in the new concepts described here. Early mirror research was carried out with circular axisymmetric magnets. These plasmas were MHD unstable due to the unfavorable magnetic curvature near the mid-plane. Then the minimum-B concept emerged in which the field line curvature was everywhere favorable and the plasma was situated in a MHD stable magnetic well (70% average beta in 2XII-B). The Ioffe-bar or baseball-coil became the standard for over 40 years. In the 1980's, driven by success with minimum-B stabilization and the control of ion cyclotron instabilities in PR6 and 2XII-B, mirrors were viewed as a potentially attractive concept with near-term advantages as a lower Q neutron source for applications such as a hybrid fission fuel factory or toxic waste burner. However there are down sides to the minimum-B geometry: coil construction is complex; restraining magnetic forces limit field strength and mirror ratios. Furthermore, the magnetic field lines have geodesic curvature which introduces resonant and neoclassical radial transport as observed in early tandem mirror experiments. So what now leads us to think that simple axisymmetric mirror plasmas can be stable? The Russian GDT experiment achieves on-axis 60% beta by peaking of the kinetic plasma pressure near the mirror throat (where the curvature is favorable) to counter-balance the average unfavorable mid-plane curvature. Then a modest augmentation of plasma pressure in the expander results in stability. The GDT

  11. Material removal characteristics of orthogonal velocity polishing tool for efficient fabrication of CVD SiC mirror surfaces

    NASA Astrophysics Data System (ADS)

    Seo, Hyunju; Han, Jeong-Yeol; Kim, Sug-Whan; Seong, Sehyun; Yoon, Siyoung; Lee, Kyungmook; Lee, Haengbok

    2015-09-01

    Today, CVD SiC mirrors are readily available in the market. However, it is well known to the community that the key surface fabrication processes and, in particular, the material removal characteristics of the CVD SiC mirror surface varies sensitively depending on the shop floor polishing and figuring variables. We investigated the material removal characteristics of CVD SiC mirror surfaces using a new and patented polishing tool called orthogonal velocity tool (OVT) that employs two orthogonal velocity fields generated simultaneously during polishing and figuring machine runs. We built an in-house OVT machine and its operating principle allows for generation of pseudo Gaussian shapes of material removal from the target surface. The shapes are very similar to the tool influence functions (TIFs) of other polishing machine such as IRP series polishing machines from Zeeko. Using two CVD SiC mirrors of 150 mm in diameter and flat surface, we ran trial material removal experiments over the machine run parameter ranges from 12.901 to 25.867 psi in pressure, 0.086 m/sec to 0.147 m/sec in tool linear velocity, and 5 to 15 sec in dwell time. An in-house developed data analysis program was used to obtain a number of Gaussian shaped TIFs and the resulting material removal coefficient varies from 3.35 to 9.46 um/psi hour m/sec with the mean value to 5.90 ± 1.26(standard deviation). We report the technical details of the new OVT machine, of the data analysis program, of the experiments and the results together with the implications to the future development of the OVT machine and process for large CVD SiC mirror surfaces.

  12. Optimization of the process chain for mirrors made of silicon carbide

    NASA Astrophysics Data System (ADS)

    Waechter, Daniel; Kroedel, Matthias; Huenten, Martin; Klocke, Fritz

    2012-09-01

    Different grades of silicon carbide (SiC) became an established material for structures as well as optical mirrors in space-borne applications. But the manufacturing still causes high efforts and restrains an extension of application in further fields. The research project MirrorFab aims for a qualification of an optimized process chain for manufacturing mirrors made of Cesic®. Cesic® consists of a matrix of SiC reinforced with chopped carbon fibers. There is a space qualified Cesic® manufacturing process and an established network for the supply chain. The project addresses the required gain in efficiency and flexibility in the manufacturing capabilities. The consortium covers the major parts of the process chain. It aims for increasing the performance of each manufacturing technology. Additionally, the consideration of the complete process chain enables a holistic optimization approach. This paper deals particularly with the process optimization of the grinding step after infiltration. The benefit of the use of an ultra precision grinding machine for mirrors in the range of 200 mm is evaluated. This paper presents the results of a systematical study on the influence of the grit size, the type of bond as well the major machining parameters on the surface roughness and the grinding forces, when machining the material Cesic®. A major finding is, that the use of ultra fine grinding wheels does not result in a superior surface quality compared to the use of a D46 grinding wheel with resinoid bond.

  13. Removing Silicon Monoxide From Nickel Mirrors

    NASA Technical Reports Server (NTRS)

    Zaniewski, John J.

    1987-01-01

    Combination of polishing tool and polishing mixture used to remove adherent fragments of silicon monoxide protective coatings from nickel/aluminum mirrors without altering shapes or harming polishes of mirror surfaces. Polishing technique developed to prepare stained mirrors for recoating to restore high reflectance.

  14. Light Weight Silicon Mirrors for Space Instrumentation

    NASA Technical Reports Server (NTRS)

    Bly, Vincent T.; Hill, Peter C.; Hagopian, John G.; Strojay, Carl R.; Miller, Timothy

    2012-01-01

    Each mirror is a monolithic structure from a single crystal of silicon. The mirrors are light weighted after the optical surface is ground and polished. Mirrors made during the initial phase of this work were typically 1/50 lambda or better (RMS at 633 n m)

  15. 21 CFR 886.1500 - Headband mirror.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Headband mirror. 886.1500 Section 886.1500 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1500 Headband mirror. (a) Identification. A headband mirror is a device intended to be strapped to the head of the user to reflect light for use...

  16. 21 CFR 886.1500 - Headband mirror.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Headband mirror. 886.1500 Section 886.1500 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1500 Headband mirror. (a) Identification. A headband mirror is a device intended to be strapped to the head of the user to reflect light for use...

  17. 21 CFR 886.1500 - Headband mirror.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Headband mirror. 886.1500 Section 886.1500 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1500 Headband mirror. (a) Identification. A headband mirror is a device intended to be strapped to the head of the user to reflect light for use...

  18. 21 CFR 886.1500 - Headband mirror.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Headband mirror. 886.1500 Section 886.1500 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1500 Headband mirror. (a) Identification. A headband mirror is a device intended to be strapped to the head of the user to reflect light for use...

  19. 21 CFR 886.1500 - Headband mirror.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Headband mirror. 886.1500 Section 886.1500 Food... DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1500 Headband mirror. (a) Identification. A headband mirror is a device intended to be strapped to the head of the user to reflect light for use...

  20. Tandem mirror next step conceptual design

    SciTech Connect

    Doggett, J.N.; Damm, C.C.; Bulmer, R.H.

    1980-10-14

    A study was made to define the features of the experimental mirror fusion device - The Tandem Mirror Next Step, or TMNS - that will bridge the gap between present mirror confinement experiments and a power-producing reactor. We outline the project goals, describe some initial device parameters, and relate the technological requirements to ongoing development programs.

  1. Through the looking-glass: mirror reading.

    PubMed

    Duñabeitia, Jon Andoni; Molinaro, Nicola; Carreiras, Manuel

    2011-02-14

    At early stages of object identification we process correctly oriented and mirrored versions of an object similarly. However, in letter and word perception, such tolerance to mirror reversals is harmful for efficient reading. Do readers successfully develop blindness mechanisms for mirror-letters and words? We conducted two masked priming experiments while recording participants' electrophysiological brain responses to briefly presented primes including mirror-letters (Experiment 1) or to shortly presented mirror-words (Experiment 2). Results showed that the human visual word recognition system is not totally blind to mirror-letters and mirror-words, since the early stages of processing mirror-letters and mirror-words produced effects on target word recognition that were highly similar to the effects produced by identical primes (N250 component). In a posterior stage of processing (N400 epoch), the effect of mirror-letters and mirror-words was different from the effect of identical primes, even though reversed primes still elicited N400 priming effects different from unrelated primes. These results demonstrate that readers perceive mirror-letters and words as correct at initial stages of word recognition, and that the visual word recognition system's neural representation is grounded on basic principles that govern object perception.

  2. Design and Fabrication of Automatic Glass Cutting Machine

    NASA Astrophysics Data System (ADS)

    Veena, T. R.; Kadadevaramath, R. S.; Nagaraj, P. M.; Madhusudhan, S. V.

    2016-09-01

    This paper deals with the design and fabrication of the automatic glass or mirror cutting machine. In order to increase the accuracy of cut and production rate; and decrease the production time and accidents caused due to manual cutting of mirror or glass, this project aims at development of an automatic machine which uses a programmable logic controller (PLC) for controlling the movement of the conveyer and also to control the pneumatic circuit. In this machine, the work of the operator is to load and unload the mirror. The cutter used in this machine is carbide wheel with its cutting edge ground to a V-shaped profile. The PLC controls the pneumatic cylinder and intern actuates the cutter along the glass, a fracture layer is formed causing a mark to be formed below the fracture layer and a crack to be formed below the rib mark. The machine elements are designed using CATIA V5R20 and pneumatic circuit are designed using FESTO FLUID SIM software.

  3. Preliminary design of a Tandem-Mirror-Next-Step facility

    SciTech Connect

    Damm, C.C.; Doggett, J.N.; Bulmer, R.H.

    1980-12-18

    The Tandem-Mirror-Next-Step (TMNS) facility is designed to demonstrate the engineering feasibility of a tandem-mirror reactor. The facility is based on a deuterium-tritium (D-T) burning, tandem-mirror device with a fusion power output of 245 MW. The fusion power density in the central cell is 2.1 MW/m/sup 3/, with a resultant neutron wall loading of 0.5 MW/m/sup 2/. Overall machine length is 116 m, and the effective central-cell length is 50.9 m. The magnet system includes end cells with yin-yang magnets to provide magnetohydrodynamic (MHD) stability and thermal-barrier cells to help achieve a plasma Q of 4.7 (where Q = fusion power/injected power). Neutral beams at energies up to 200 keV are used for plasma heating, fueling, and barrier pumping. Electron cyclotron resonant heating at 50 and 100 GHz is used to control the electron temperature in the barriers. Based on the resulting engineering design, the overall cost of the facility is estimated to be just under $1 billion. Unresolved physics issues include central-cell ..beta..-limits against MHD ballooning modes (the assumed reference value of ..beta.. exceeds the current theory-derived limit), and the removal of thermalized ..cap alpha..-particles from the plasma.

  4. Assembly aligning and measuring of a reflective telescope primary mirror

    NASA Astrophysics Data System (ADS)

    Wu, Kun-Huan; Lie, Chun-Chieh; Lin, Yu-Chuan; Chan, Chia-Yen; Huang, Ting-Ming; Hsu, Ming-Ying

    2016-09-01

    Gluing technology has been widely used in aerospace, optical, electrical and mechanical and other related industries, and already has excellent bonding strength, mechanical properties and airtightness, gluing material selection and process which is a key issue. In this paper, we choice EC2216 glue to assemble a reflective telescope primary mirror. In this study, a lightweight aluminum mirror with a diameter of 566 mm with three stainless parts have been taken as the gluing and assembly benchmark. We control the thickness of the glue between 0.35 +/- 0.15 mm by a 0.3 mm shim, and control stainless parts on the Neutral plane effectively at the same time, after the installation of bipod in the future, this assembly can ensure effective verification to avoid stress is transmitted to the mirror distortion caused by the optical system. This paper aims to provide assembly and aligning by coordinate measurement machine (CMM). In order to obtain more accurate optimization results, we trace parts and the measurement results of CMM.

  5. Study Of Pre-Shaped Membrane Mirrors And Electrostatic Mirrors With Nonlinear-Optical Correction

    DTIC Science & Technology

    2002-01-01

    mirrors have been manufactured of glass-like material Zerodur with very low coefficient of linear expansion. They have a more light cellular construction...primary and flat secondary mirrors are both segmented ones. In the case of the primary mirror made of traditional materials such as Zerodur or fused...FINAL REPORT ISTC Project #2103p “Study of Pre-Shaped Membrane Mirrors and Electrostatic Mirrors with Nonlinear-Optical Correction” Manager

  6. Implementation of Bluetooth technology in processing aspheric mirrors

    NASA Astrophysics Data System (ADS)

    Chen, Dong-yun; Li, Xiao-jin

    2010-10-01

    This paper adopts the Bluetooth wireless transmission to replace the conducting rings currently using in the active lap process to overcome the cost and abrasion problems brought by the conducting rings, which has great significance for reducing the costs of processing large aspheric mirrors. Based on the actual application requirements, Article proposes the overall program of using Bluetooth technology as data transmission, including the active lap-side and machine tool-side: In the machine tool-side, the MCU separately connects with Bluetooth module and the sensor via UART0 and UART1 serial port, and when the MCU receives the signals sending from the sensor, the MCU packs and then sends them through the Bluetooth module; while in the active lap side, the CCAL reads-out the position signals of sensor detecting in dual-port memory via one-side ports, and the other side ports connect with the MCU's high ports P4-P7, so the MCU can unpacks and stores the position signals receiving via Bluetooth module. This paper designs and implements the system's hardware circuit, and mainly introduces the ways of serial and parallel. Based upon the realized system, design the test program for the Bluetooth wireless transmission and the experiment results, in the condition of the active lap processing large aspheric mirrors, showed that Bluetooth technology can meet the requirements of practical applications.

  7. First Results of the Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2002-01-01

    An experimental Gasdynamic Mirror or GDM device has been constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the applicability of this technology for propulsion systems. This paper presents the first experimental results obtained from the machine and an analysis of the types of plasma instabilities likely to be encountered. It is intended that this device operate at higher plasma densities and with much larger L/D ratios than previous mirror machines. The high L/D ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. The high plasma density results in the plasma behaving much more like a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. The device has been constructed to allow a considerable degree of flexibility in its configuration thus permitting the experiment to grow over time without necessitating a great deal of additional fabrication.

  8. Polarization aberrations of crossed folding mirrors

    NASA Astrophysics Data System (ADS)

    Crandall, David G.; Chipman, Russell A.

    1995-08-01

    Polarization aberrations due to varying polarization state across the field of view (FOV) are investigated for crossed folding mirrors. We define crossed mirrors as oriented in space such that s-polarized light incident on the first mirror is p-polarized at the second mirror. This completely compensates for polarization state changes at one point in the field of view. The resulting polarization aberrations are explored across the FOV using the example of aluminum mirrors overcoated with a 12 layer, highly reflective, dielectric stack. The polarization aberration is very low along a band across the field of view. For arbitrary points in the FOV, the retardance and diattenuation are slightly elliptical.

  9. [What mirror neurons have revealed: revisited].

    PubMed

    Murata, Akira; Maeda, Kazutaka

    2014-06-01

    The first paper on mirror neurons was published in 1992. In the span of over two decades since then, much knowledge about the relationship between social cognitive function and the motor control system has been accumulated. Direct matching of visual actions and their corresponding motor representations is the most important functional property of mirror neuron. Many studies have emphasized intrinsic simulation as a core concept for mirror neurons. Mirror neurons are thought to play a role in social cognitive function. However, the function of mirror neurons in the macaque remains unclear, because such cognitive functions are limited or lacking in macaque monkeys. It is therefore important to discuss these neurons in the context of motor function. Rizzolatti and colleagues have stressed that the most important function of mirror neurons in macaques is recognition of actions performed by other individuals. I suggest that mirror neurons in the Macaque inferior pariental lobule might be correlated with body schema. In the parieto-premotor network, matching of corollary discharge and actual sensory feedback is an essential neuronal operation. Recently, neurons showing mirror properties were found in some cortical areas outside the mirror neuron system. The current work would revisit the outcomes of mirror neuron studies to discuss the function of mirror neurons in the monkey.

  10. New and improved technology for manufacture of GMT primary mirror segments

    NASA Astrophysics Data System (ADS)

    Kim, Dae Wook; Burge, James H.; Davis, Jonathan M.; Martin, Hubert M.; Tuell, Michael T.; Graves, Logan R.; West, Steve C.

    2016-07-01

    The Giant Magellan Telescope (GMT) primary mirror consists of seven 8.4 m light-weight honeycomb mirrors that are being manufactured at the Richard F. Caris Mirror Lab (RFCML), University of Arizona. In order to manufacture the largest and most aspheric astronomical mirrors various high precision fabrication technologies have been developed, researched and implemented at the RFCML. The unique 8.4 m (in mirror diameter) capacity fabrication facilities are fully equipped with large optical generator (LOG), large polishing machine (LPM), stressed lap, rigid conformal lap (RC lap) and their process simulation/optimization intelligence called MATRIX. While the core capability and key manufacturing technologies have been well demonstrated by completing the first GMT off-axis segment, there have been significant hardware and software level improvements in order to improve and enhance the GMT primary mirror manufacturing efficiency. The new and improved manufacturing technology plays a key role to realize GMT, the next generation extremely large telescope enabling new science and discoveries, with high fabrication efficiency and confidence.

  11. MODEL SIMULATIONS OF CONTINUOUS ION INTERJECTION INTO EBIS TRAP WITH SLANTED ELECTROSTATIC MIRROR.

    SciTech Connect

    PIKIN,A.; KPONOU, A.; ALESSI, J.G.; BEEBE, E.N.; PRELEC, K.; RAPARIA, D.

    2007-08-26

    The efficiency of trapping ions in an EBIS is of primary importance for many applications requiring operations with externally produced ions: RIA breeders, ion sources, traps. At the present time, the most popular method of ion injection is pulsed injection, when short bunches of ions get trapped in a longitudinal trap while traversing the trap region. Continuous trapping is a challenge for EBIS devices because mechanisms which reduce the longitudinal ion energy per charge in a trap (cooling with residual gas, energy exchange with other ions, ionization) are not very effective, and accumulation of ions is slow. A possible approach to increase trapping efficiency is to slant the mirror at the end of the trap which is opposite to the injection end. A slanted mirror will convert longitudinal motion of ions into transverse motion, and, by reducing their longitudinal velocity, prevent these ions from escaping the trap on their way out. The trade off for the increased trapping efficiency this way is an increase in the initial transverse energy of the accumulated ions. The slanted mirror can be realized if the ends of two adjacent electrodes- drift tubes - which act as an electrostatic mirror, are machined to produce a slanted gap, rather than an upright one. Applying different voltages to these electrodes will produce a slanted mirror. The results are presented of 2D and 3D computer simulations of ion injection into a simplified model of EBIS with slanted mirror.

  12. JWST Lightweight Mirror TRL-6 Results

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2007-01-01

    Mirror technology for a Primary Mirror Segment Assembly (PMSA) is a system of components: reflective coating; polished optical surface; mirror substrate; actuators, mechanisms and flexures; and reaction structure. The functional purpose of a PMSA is to survive launch, deploy and align itself to form a 25 square meter collecting area 6.5 meter diameter primary mirror with a 131 nm rms wavefront error at temperatures less than 50K and provide stable optical performance for the anticipated thermal environment. At the inception of JWST in 1996, such a capability was at a Technology Readiness Level (TRL) of 3. A highly successful technology development program was initiated including the Sub-scale Beryllium Mirror Demonstrator (SBMD) and Advanced Mirror System Demonstrator (AMSD) projects. These projects along with flight program activities have matured mirror technology for JWST to TRL-6. A directly traceable prototype (and in some cases the flight hardware itself) has been built, tested and operated in a relevant environment.

  13. A Deployable Primary Mirror for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Phelps, James E.; Dyer, Jack E.; Caudle, David A.; Tam, Anthony; Escobedo, Javier; Kasl, Eldon P.

    1999-01-01

    NASA Langley Research Center, Composite Optics, Inc., and Nyma/ADF have developed jointly a deployable primary mirror for space telescopes that combines over five years of research on deployment of optical-precision structures and over ten years of development of fabrication techniques for optical-precision composite mirror panels and structures. The deployable mirror is directly applicable to a broad class of non-imaging "lidar" (light direction and ranging) telescopes whose figure-error requirements are in the range of one to ten microns RMS. Furthermore, the mirror design can be readily modified to accommodate imaging-quality reflector panels and active panel-alignment control mechanisms for application to imaging telescopes. The present paper: 1) describes the deployable mirror concept; 2) explains the status of the mirror development; and 3) provides some technical specifications for a 2.55-m-diameter, proof-of-concept mirror.

  14. Radius of curvature controlled mirror

    DOEpatents

    Neil, George R.; Rathke, John Wickham; Schultheiss, Thomas John; Shinn, Michelle D.; Dillon-Townes, Lawrence A.

    2006-01-17

    A controlled radius of curvature mirror assembly comprising: a distortable mirror having a reflective surface and a rear surface; and in descending order from the rear surface; a counter-distortion plate; a flow diverter having a flow diverter aperture at the center thereof; a flow return plate having a flow return aperture at the center thereof; a thermal isolation plate having a thermal isolation plate aperture at the center thereof and a flexible heater having a rear surface and a flexible heater aperture at the center thereof; a double walled tube defining a coolant feed chamber and a coolant return chamber; said coolant feed chamber extending to and through the flow diverter aperture and terminating at the counter-distortion plate and the coolant return chamber extending to and through the thermal isolation backplate and terminating at the flow diverter; and a coolant feed and a coolant return exit at the rear of said flexible heater.

  15. Mirror symmetry for Enriques surfaces

    NASA Astrophysics Data System (ADS)

    Lakuriqi, Enkeleida

    In this thesis, we investigate three separate but related projects. In the first one, we describe the geometric backgrounds of Type II string theory which are given by Enriques surfaces and their mirrors. We also study the effect of various string dualities on such backgrounds, in particular phase change in Gauged Linear Sigma Models and mirror symmetry. In the second project, we investigate special Kahler geometry in order to find canonical coordinates on the moduli of generalised Calabi-Yau spaces and the associated (2, 2) superconformal field theories. In the third project, we develop a general technique for computing the massless spectrum of (0, 2) quantum field theory compactified on a proper stack or an orbifold. We produce general formulas for the contribution of the twisted sectors and compute specific examples of compactifications on gerbes on projective spaces and Calabi-Yau threefolds.

  16. The alignment of the aerospace Cassegrain telescope primary mirror and iso-static mount by using CMM

    NASA Astrophysics Data System (ADS)

    Lin, Wei-Cheng; Chang, Shenq-Tsong; Lin, Yu-Chuan; Cheng, Yu-Cheng; Hsu, Ming-Ying; Huang, Ting-Ming

    2011-10-01

    In order to meet both optical performance and structural stiffness requirements of the aerospace Cassegrain telescope, the primary mirror shall be mounted with the main plate by iso-static mount. This article describes of the alignment of the aerospace Cassegrain telescope's primary mirror and iso-static mount by using coordinate-measuring machine (CMM), and the design and assembly of mechanical ground support equipment (MGSE). The primary mirror adjusting MGSE consists of three 3-axis linear stages and point contact platforms, which hold the mirror while avoid the rotated movement when adjusting the stage. This MGSE provide the adjustment of tilt and height for the mirror. After the CMM measurement, the coordinates of measured point on the mirror will be analyzed by the software based on least square fitting to find the radius of curvature, conic constant, de-center and tilt, etc. According to these results, the mirror posture will be adjusted to reduce de-center and tilt by the designed MGSE. The tilt in x and y direction are reduced within 0.001 degrees and the distance deviation from the best fitted profile of the mirror to the main plate shall be less than 0.008mm.

  17. Machine musicianship

    NASA Astrophysics Data System (ADS)

    Rowe, Robert

    2002-05-01

    The training of musicians begins by teaching basic musical concepts, a collection of knowledge commonly known as musicianship. Computer programs designed to implement musical skills (e.g., to make sense of what they hear, perform music expressively, or compose convincing pieces) can similarly benefit from access to a fundamental level of musicianship. Recent research in music cognition, artificial intelligence, and music theory has produced a repertoire of techniques that can make the behavior of computer programs more musical. Many of these were presented in a recently published book/CD-ROM entitled Machine Musicianship. For use in interactive music systems, we are interested in those which are fast enough to run in real time and that need only make reference to the material as it appears in sequence. This talk will review several applications that are able to identify the tonal center of musical material during performance. Beyond this specific task, the design of real-time algorithmic listening through the concurrent operation of several connected analyzers is examined. The presentation includes discussion of a library of C++ objects that can be combined to perform interactive listening and a demonstration of their capability.

  18. Oculometer focus and mirror control

    NASA Technical Reports Server (NTRS)

    Guy, W. J.

    1982-01-01

    An automatic focusing system designed around an ultrasonic range measurement is described. Besides maintaining the focus, subject distance is a by-product which could lighten the NOVA computational effort. An automatic head tracking unit is also discussed. It is intended to reduce the search time required when track is lost. An X-Y ultrasonic measurement is also made in this design to control the deflection mirrors.

  19. Construction of Prototype Lightweight Mirrors

    NASA Technical Reports Server (NTRS)

    Robinson, William G.

    1997-01-01

    This contract and the work described was in support of a Seven Segment Demonstrator (SSD) and demonstration of a different technology for construction of lightweight mirrors. The objectives of the SSD were to demonstrate functionality and performance of a seven segment prototype array of hexagonal mirrors and supporting electromechanical components which address design issues critical to space optics deployed in large space based telescopes for astronomy and for optics used in spaced based optical communications systems. The SSD was intended to demonstrate technologies which can support the following capabilities; Transportation in dense packaging to existing launcher payload envelopes, then deployable on orbit to form space telescope with large aperture. Provide very large (less than 10 meters) primary reflectors of low mass and cost. Demonstrate the capability to form a segmented primary or quaternary mirror into a quasi-continuous surface with individual subapertures phased so that near diffraction limited imaging in the visible wavelength region is achieved. Continuous compensation of optical wavefront due to perturbations caused by imperfections, natural disturbances, and equipment induced vibrations/deflections to provide near diffraction limited imaging performance in the visible wavelength region. Demonstrate the feasibility of fabricating such systems with reduced mass and cost compared to past approaches. While the SSD could not be expected to satisfy all of the above capabilities, the intent was to start identifying and understanding new technologies that might be applicable to these goals.

  20. Flotation machine

    SciTech Connect

    Zlobin, M.N.; Permyakov, G.P.; Nemarov, A.A.; Metsik, V.M.; Medetsky, J.V.; Taraban, N.T.

    1993-08-10

    A flotation machine is described for beneficiating minerals comprising: a vertical cylindrical chamber for circulating a flotation pulp; a downwardly tapered bottom connected to said vertical cylindrical chamber; feed pipe means for feeding the flotation pulp carrying mineral particles of fine fraction, particles of the useful ingredient of the fine fraction being capable of floating up from the volume of said aerated pulp; discharge pipe means connected to the tapered bottom near its lowest point for discharging gangue; an annular trough for collecting froth concentrate at the top of said chamber; a group of frustoconical shells each having bases of different diameters and a tapered surface secured axially in said chamber and spaced equidistantly from one another height wise of said chamber; aerator means for aerating the flotation pulp secured to the walls of said chamber and communicating therewith to provide aerated water into said chamber; means for feeding mineral particles of coarse fraction, particles of the useful ingredient of the coarse fraction being capable of floating in the froth layer of the flotation pulp, in the form of a hydrocyclone having a cylindrical casing positioned axially over said chamber and a downwardly tapering outlet directed downwardly to feed the coarse particles to said chamber; feed pipe means for feeding the flotation pulp carrying mineral particles of coarse fraction positioned tangentially at said cylindrical casing of the hydrocyclone; and evacuation means for evacuating the liquid phase of the flotation pulp positioned tangentially at said casing of the hydrocyclone over said feed pipe means and connected to said feed pipe means for feeding the flotation pulp carrying mineral particles of the fine fraction.

  1. Mirror Metrology Using Nano-Probe Supports

    NASA Technical Reports Server (NTRS)

    Robinson, David; Hong, Maoling; Byron, Glenn; McClelland, Ryan; Chan, Kai-Wing

    2012-01-01

    Thin, lightweight mirrors are needed for future x-ray space telescopes in order to increase x-ray collecting area while maintaining a reduced mass and volume capable of being launched on existing rockets. However, it is very difficult to determine the undistorted shape of such thin mirrors because the mounting of the mirror during measurement causes distortion. Traditional kinematic mounts have insufficient supports to control the distortion to measurable levels and prevent the mirror from vibrating during measurement. Over-constrained mounts (non-kinematic) result in an unknown force state causing mirror distortion that cannot be determined or analytically removed. In order to measure flexible mirrors, it is necessary to over-constrain the mirror. Over-constraint causes unknown distortions to be applied to the mirror. Even if a kinematic constraint system can be used, necessary imperfections in the kinematic assumption can lead to an unknown force state capable of distorting the mirror. Previously, thicker, stiffer, and heavier mirrors were used to achieve low optical figure distortion. These mirrors could be measured to an acceptable level of precision using traditional kinematic mounts. As lighter weight precision optics have developed, systems such as the whiffle tree or hydraulic supports have been used to provide additional mounting supports while maintaining the kinematic assumption. The purpose of this invention is to over-constrain a mirror for optical measurement without causing unacceptable or unknown distortions. The invention uses force gauges capable of measuring 1/10,000 of a Newton attached to nano-actuators to support a thin x-ray optic with known and controlled forces to allow for figure measurement and knowledge of the undeformed mirror figure. The mirror is hung from strings such that it is minimally distorted and in a known force state. However, the hanging mirror cannot be measured because it is both swinging and vibrating. In order to

  2. Manufacturing Large Membrane Mirrors at Low Cost

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Relatively inexpensive processes have been developed for manufacturing lightweight, wide-aperture mirrors that consist mainly of reflectively coated, edge-supported polyimide membranes. The polyimide and other materials in these mirrors can withstand the environment of outer space, and the mirrors have other characteristics that make them attractive for use on Earth as well as in outer space: With respect to the smoothness of their surfaces and the accuracy with which they retain their shapes, these mirrors approach the optical quality of heavier, more expensive conventional mirrors. Unlike conventional mirrors, these mirrors can be stowed compactly and later deployed to their full sizes. In typical cases, deployment would be effected by inflation. Potential terrestrial and outer-space applications for these mirrors include large astronomical telescopes, solar concentrators for generating electric power and thermal power, and microwave reflectors for communication, radar, and short-distance transmission of electric power. The relatively low cost of manufacturing these mirrors stems, in part, from the use of inexpensive tooling. Unlike in the manufacture of conventional mirrors, there is no need for mandrels or molds that have highly precise surface figures and highly polished surfaces. The surface smoothness is an inherent property of a polyimide film. The shaped area of the film is never placed in contact with a mold or mandrel surface: Instead the shape of a mirror is determined by a combination of (1) the shape of a fixture that holds the film around its edge and (2) control of manufacturing- process parameters. In a demonstration of this manufacturing concept, spherical mirrors having aperture diameters of 0.5 and 1.0 m were fabricated from polyimide films having thicknesses ranging from <20 m to 150 m. These mirrors have been found to maintain their preformed shapes following deployment.

  3. Assessment of cleaning methods for first mirrors tested in JET for ITER

    NASA Astrophysics Data System (ADS)

    Ivanova, D.; Widdowson, A.; Likonen, J.; Marot, L.; Koivuranta, S.; Coad, J. P.; Rubel, M.; Petersson, P.; De Temmerman, G.; JET-EFDA Contributors

    2013-07-01

    Two cleaning techniques were used for removal of co-deposits from the tested first mirrors exposed in JET: (a) ultrasonic bath; (b) a broad range of polishing conditions from manual buffing to machine polishing with the diamond grain size of up to 3 μm. Reflectivity measurements were performed after each step in the cleaning procedure. Surfaces were also examined with electron microscopy and ion beam analysis methods. Ultrasonic cleaning leads to partial recovery of reflectivity due to enhanced detachment of deposits. Typically 30-50% of the original reflectivity was recovered in the visible light and 50-90% in the infrared region. One mirror was cleaned completely. Polishing with diamond paste may lead to successful removal of deposits but the damage to the surface in case of the large diamond grains was observed. Recovery of up to 100% of the initial reflectivity was achieved for some mirrors.

  4. Marking LANDSAT images with small mirror reflectors. [in Virginia and California

    NASA Technical Reports Server (NTRS)

    Evans, W. E.

    1975-01-01

    Uniquely identifiable artificial landmarks were generated in LANDSAT imagery by making use of specular solar reflection from small, easily transportable mirrors. The results are impressive in well-registered color composite enlargements, where the mirror returns appear as bright white spots. The signatures are unique enough that returns can be readily located in the computer compatible tape records either manually or by machine search. As embodied in experiments to date, the system is entirely passive. Mirrors must be carefully positioned prior to each satellite pass, but the required angle calculations are simple enough to be made on a hand calculator and the required input data are easily available. Possible applications of the technique include providing site identification and geodetic control in remote regions of the earth, enhancement of small targets such as offshore oil derricks, providing atmospheric transmission data coincident with other LANDSAT experiments, and providing a nearly perfect optical point source for overall system checkout.

  5. Diamond machining of micro-optical components and structures

    NASA Astrophysics Data System (ADS)

    Gläbe, Ralf; Riemer, Oltmann

    2010-05-01

    Diamond machining originates from the 1950s to 1970s in the USA. This technology was originally designed for machining of metal optics at macroscopic dimensions with so far unreached tolerances. During the following decades the machine tools, the monocrystalline diamond cutting tools, the workpiece materials and the machining processes advanced to even higher precision and flexibility. For this reason also the fabrication of small functional components like micro optics at a large spectrum of geometries became technologically and economically feasible. Today, several kinds of fast tool machining and multi axis machining operations can be applied for diamond machining of micro optical components as well as diffractive optical elements. These parts can either be machined directly as single or individual component or as mold insert for mass production by plastic replication. Examples are multi lens arrays, micro mirror arrays and fiber coupling lenses. This paper will give an overview about the potentials and limits of the current diamond machining technology with respect to micro optical components.

  6. Magnetic mirror fusion: status and prospects

    SciTech Connect

    Post, R.F.

    1980-02-11

    Two improved mirror systems, the tandem mirror (TM) and the field-reversed mirror (FRM) are being intensively studied. The twin practical aims of these studies: to improve the economic prospects for mirror fusion power plants and to reduce the size and/or complexity of such plants relative to earlier approaches to magnetic fusion. While at the present time the program emphasis is still strongly oriented toward answering scientific questions, the emphasis is shifting as the data accumulates and as larger facilities - ones with a heavy technological and engineering orientation - are being prepared. The experimental and theoretical progress that led to the new look in mirror fusion research is briefly reviewed, the new TM and the FRM ideas are outlined, and the projected future course of mirror fusion research is discussed.

  7. Deformable mirrors development program at ESO

    NASA Astrophysics Data System (ADS)

    Stroebele, Stefan; Vernet, Elise; Brinkmann, Martin; Jakob, Gerd; Lilley, Paul; Casali, Mark; Madec, Pierre-Yves; Kasper, Markus

    2016-07-01

    Over the last decade, adaptive optics has become essential in different fields of research including medicine and industrial applications. With this new need, the market of deformable mirrors has expanded a lot allowing new technologies and actuation principles to be developed. Several E-ELT instruments have identified the need for post focal deformable mirrors but with the increasing size of the telescopes the requirements on the deformable mirrors become more demanding. A simple scaling up of existing technologies from few hundred actuators to thousands of actuators will not be sufficient to satisfy the future needs of ESO. To bridge the gap between available deformable mirrors and the future needs for the E-ELT, ESO started a development program for deformable mirror technologies. The requirements and the path to get the deformable mirrors for post focal adaptive optics systems for the E-ELT is presented.

  8. Tandem mirror technology demonstration facility

    SciTech Connect

    Not Available

    1983-10-01

    This report describes a facility for generating engineering data on the nuclear technologies needed to build an engineering test reactor (ETR). The facility, based on a tandem mirror operating in the Kelley mode, could be used to produce a high neutron flux (1.4 MW/M/sup 2/) on an 8-m/sup 2/ test area for testing fusion blankets. Runs of more than 100 h, with an average availability of 30%, would produce a fluence of 5 mW/yr/m/sup 2/ and give the necessary experience for successful operation of an ETR.

  9. Deformable Mirrors Correct Optical Distortions

    NASA Technical Reports Server (NTRS)

    2010-01-01

    By combining the high sensitivity of space telescopes with revolutionary imaging technologies consisting primarily of adaptive optics, the Terrestrial Planet Finder is slated to have imaging power 100 times greater than the Hubble Space Telescope. To this end, Boston Micromachines Corporation, of Cambridge, Massachusetts, received Small Business Innovation Research (SBIR) contracts from the Jet Propulsion Laboratory for space-based adaptive optical technology. The work resulted in a microelectromechanical systems (MEMS) deformable mirror (DM) called the Kilo-DM. The company now offers a full line of MEMS DMs, which are being used in observatories across the world, in laser communication, and microscopy.

  10. Process for preparing improved silvered glass mirrors

    DOEpatents

    Buckwalter, Jr., Charles Q.

    1981-01-01

    Glass mirrors having improved weathering properties are prepared by an improvement in the process for making the mirrors. The glass surface after it has been cleaned but before it is silvered, is contacted with a solution of lanthanide rare earths in addition to a sensitization solution of tin or palladium. The addition of the rare earths produces a mirror which has increased resistance to delamination of the silver from the glass surface in the presence of water.

  11. Process for preparing improved silvered glass mirrors

    DOEpatents

    Buckwalter, C.Q. Jr.

    1980-01-28

    Glass mirrors having improved weathering properties are prepared by an improvement in the process for making the mirrors. The glass surface after it has been cleaned but before it is silvered, is contacted with a solution of lanthanide rare earths in addition to a sensitization solution of tin or palladium. The addition of the rare earths produces a mirror which has increased resistance to delamination of the silver from the glass surface in the presence of water.

  12. Silicon Carbide Technologies for Lightweighted Aerospace Mirrors

    DTIC Science & Technology

    2008-09-01

    Silicon Carbide Technologies for Lightweighted Aerospace Mirrors Lawrence E. Matson (1) Ming Y. Chen (1) Brett deBlonk (2) Iwona A...glass and beryllium to produce lightweighted aerospace mirror systems has reached its limits due to the long lead times, high processing costs...for making mirror structural substrates, figuring and finishing technologies being investigated to reduce cost time and cost, and non-destructive

  13. White Light Holography Using Flexible Membrane Mirrors

    NASA Astrophysics Data System (ADS)

    Warren, D.; King, W.; Waddell, P.; Raptodimos, T.

    1988-06-01

    White light transmission holograms have been made using revolutionary flexible membrane concave mirrors of variable focal length. These mirrors are used as collimators to produce and project conjugate imagery for making white light holograms. The era of super large scale white light holography with undistorted imagery and large angular field of view is predicted, based on current results and the availability of very wide plastic sheets suitable for use as the reflective membrane of the flexible mirrors.

  14. Deformable mirror for short wavelength applications

    DOEpatents

    Chapman, Henry N.; Sweeney, Donald W.

    1999-01-01

    A deformable mirror compatible with short wavelength (extreme ultraviolet) radiation that can be precisely controlled to nanometer and subnanometer accuracy is described. Actuators are coupled between a reaction plate and a face plate which has a reflective coating. A control system adjusts the voltage supplied to the actuators; by coordinating the voltages supplied to the actuators, the reflective surface of the mirror can be deformed to correct for dimensional errors in the mirror or to produce a desired contour.

  15. Segmented Mirror Telescope Model and Simulation

    DTIC Science & Technology

    2011-06-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS SEGMENTED MIRROR TELESCOPE MODEL AND SIMULATION by Travis W. Axtell June 2011 Thesis Co...Mirror Telescope Model and Simulation Travis W. Axtell Naval Postgraduate School Monterey, CA 93943 Department of the Navy Approved for public release...Department of Defense or the U.S. Government. IRB Protocol Number: N/A The Segmented Mirror Telescope (SMT) housed at the Naval Postgraduate School is a

  16. Advanced Mirror System Demonstrator (AMSD) Risk Management

    NASA Technical Reports Server (NTRS)

    Byberg, Alicia; Russell, J. Kevin; Kaukler, Donna; Burdine, Robert V. (Technical Monitor)

    2002-01-01

    This paper will report risk issues associated with designing, manufacturing, and testing the Advanced Mirror System Demonstrator (AMSD). The Advanced Mirror System Demonstrator (AMSD) will be developed as a lightweight primary mirror system that can be produced at a low cost and with a short manufacturing schedule. This technology will add to the knowledge base for selection for the Next Generation Space Telescope (NGST), Space Based Laser (SBL), Research Laboratory mission (AFRL), and other government agency programs.

  17. Astronomical Secondary Mirrors And Field Correctors: Special Challenges And Metrology Solutions Routinely Used At Brashear

    NASA Astrophysics Data System (ADS)

    Piche, Francios; Gardopee, G.; Clarkson, A.; Hull, T.

    2012-01-01

    It has been said that the secondary mirror is the most difficult optic of an astronomical telescope. Much of this difficulty is associated with metrology of a convex mirror. With the advent of highly deterministic modern optical finishing machines delivering high process convergence rates, like those processes used at L-3 Integrated Optical Systems (IOS), the availability of high-quality metrology on convex optical surfaces is of greater importance to take full advantage of those new technological capabilities. Once the surface error map is determined, modern optical finishing machines, like those at L-3 Integrated Optical Systems (IOS), can readily make the correction, even on optics mounted in their deliverable cells. Due to IOS' innovative engineering coupled with our extensive experience with large, fast secondary mirrors, we have delivered exceptional mirrors on short schedules. We frequently address requirements where the optical figure must be controlled to a few nanometers in wavefront error, and associated metrology must address not only low spatial frequencies (LSF), but also mid spatial frequencies (MSF) and high spatial frequencies (HSF). Special tooling and techniques that control the accumulated error are described, and examples of control of all spatial frequencies presented. Methods are available at IOS to remove predicted mounting dimples whether measured in-situ with the optics mounted in its cell or predicted from a finite-element model of the mounted optic. We will also describe metrology methods for astronomical field correctors.

  18. Fabrication of experimental three-meter space telescope primary and secondary mirror support structure

    NASA Technical Reports Server (NTRS)

    Mishler, H. W.

    1974-01-01

    The fabrication of prototype titanium alloy primary and secondary mirror support structures for a proposed experimental three-meter space telescope is discussed. The structure was fabricated entirely of Ti-6Al-4V tubing and plate. Fabrication included the development of procedures including welding, forming, and machining. Most of the structures was fabricated by gas-shielding tungsten-arc (GTA) welding with several major components fabricated by high frequency resistance (HFR) welding.

  19. Development of ultra-light-weight mirror with carbon/carbon composites for optical-IR astronomy

    NASA Astrophysics Data System (ADS)

    Takeya, Hajime; Kume, Masami; Hahn, Steven; Ozaki, Tsuyoshi; Kohara, Naoki; Otsubo, Masashi; Tsuneta, Saku

    2004-10-01

    Future large aperture telescope projects will require very lightweight mirrors that can be produced at significantly lower cost and faster production times than currently possible. Tailorable, low thermal expansion composite materials offer an attractive path to achieve these goals. Application of carbon/carbon composites is particularly attractive as these materials do not exhibit the moisture-absorption-related expansion problems observed in typical resin matrix composites. The National Astronomical Observatory of Japan and Mitsubishi Electric Corporation are collaborating to develop materials and surface finishing technologies to enable future carbon/carbon composite mirror applications. Material processing techniques for improved substrate surface finish have been developed. An innovative surface finish approach involving high precision machining of a metal layer applied to the mirror surface has also been developed. As a result, 150mm diameter C/C spherical mirror with honeycomb sandwich structure was successfully demonstrated.

  20. Multilayer dielectric narrow band mangin mirror

    NASA Astrophysics Data System (ADS)

    Ahmed, K.; Khan, A. N.; Rauf, A.; Gul, A.

    2014-06-01

    The design of multilayer stack of dielectric films for narrow band mirror is developed using thin film coating software. The proposed design is materialized by employing thin film coating (PVD) method and reflectance in narrow band spectrum range is achieved. Thickness of high and low refractive index material is taken precisely up to nanometer level. The curved coated substrate is cemented with another K9 matching substrate that forms a Mangin mirror for wavelength 650nm. Narrow band mirrors with reflectivity more than 90% has been produced by properly stacking of 21 layers and advantage of the use of this type of mirror as an interference filter is discussed.

  1. Dynamical Casimir effect with δ -δ' mirrors

    NASA Astrophysics Data System (ADS)

    Silva, Jeferson Danilo L.; Braga, Alessandra N.; Alves, Danilo T.

    2016-11-01

    We calculate the spectrum and the total rate of created particles for a real massless scalar field in 1 +1 dimensions, in the presence of a partially transparent moving mirror simulated by a Dirac δ -δ' point interaction. We show that, for this model, a partially reflecting mirror can produce a larger number of particles in comparison with a perfect one. In the limit of a perfect mirror, our formulas recover those found in the literature for the particle creation by a moving mirror with a Robin boundary condition.

  2. Mounting with compliant cylinders for deformable mirrors.

    PubMed

    Reinlein, Claudia; Goy, Matthias; Lange, Nicolas; Appelfelder, Michael

    2015-04-01

    A method is presented to mount large aperture unimorph deformable mirrors by compliant cylinders (CC). The CCs are manufactured from a soft silicone, and shear testing is performed in order to evaluate the Young's modulus. A scale mirror model is assembled to evaluate mount-induced change of piezoelectric deformation, and its applicability for tightly focusing mirrors. Experiments do not show any decrease of piezoelectric stroke. Further it is shown that the changes of surface fidelity by the attachment of the deformable mirror to its mount are neglectable.

  3. Topology optimization design of a space mirror

    NASA Astrophysics Data System (ADS)

    Liu, Jiazhen; Jiang, Bo

    2015-11-01

    As key components of the optical system of the space optical remote sensor, Space mirrors' surface accuracy had a direct impact that couldn't be ignored of the imaging quality of the remote sensor. In the future, large-diameter mirror would become an important trend in the development of space optical technology. However, a sharp increase in the mirror diameter would cause the deformation of the mirror and increase the thermal deformation caused by temperature variations. A reasonable lightweight structure designed to ensure the optical performance of the system to meet the requirements was required. As a new type of lightweight approach, topology optimization technology was an important direction of the current space optical remote sensing technology research. The lightweight design of rectangular mirror was studied. the variable density method of topology optimization was used. The mirror type precision of the mirror assemblies was obtained in different conditions. PV value was less than λ/10 and RMS value was less than λ/50(λ = 632.8nm). The results show that the entire The mirror assemblies can achieve a sufficiently high static rigidity, dynamic stiffness and thermal stability and has the capability of sufficient resistance to external environmental interference . Key words: topology optimization, space mirror, lightweight, space optical remote sensor

  4. Double curvature mirrors for linear concentrators

    NASA Astrophysics Data System (ADS)

    Lance, Tamir; Ackler, Harold; Finot, Marc

    2012-10-01

    Skyline Solar's medium concentration photovoltaic system uses quasi-parabolic mirrors and one axis tracking. Improvements in levelized cost of energy can be achieved by effective management of non-uniformity of the flux line on the panels. To reduce non uniformity of the flux line due to mirror to mirror gaps, Skyline developed a dual curvature mirror that stretches the flux line along the panel. Extensive modeling and experiments have been conducted to analyze the impact of this new design and to optimize the design.

  5. The uncanny mirror: a re-framing of mirror self-experience.

    PubMed

    Rochat, Philippe; Zahavi, Dan

    2011-06-01

    Mirror self-experience is re-casted away from the cognitivist interpretation that has dominated discussions on the issue since the establishment of the mirror mark test. Ideas formulated by Merleau-Ponty on mirror self-experience point to the profoundly unsettling encounter with one's specular double. These ideas, together with developmental evidence are re-visited to provide a new, psychologically and phenomenologically more valid account of mirror self-experience: an experience associated with deep wariness.

  6. One mirror beam steering: determination of steering mirror parameters from image pointing direction

    NASA Astrophysics Data System (ADS)

    Andersen, Torben B.; Granger, Zachary A.

    2016-09-01

    Mathematical models are used to establish the exact path of a beam reflected by a plane mirror in terms of the mirror geometry descriptors. In particular, the mirror geometry descriptors (tilt angles) are determined as functions of the beam path in image space. This is also useful for determining scan patterns when the mirror is used as a scanning device. These formulations are readily adaptable to commercially available ray tracing programs.

  7. Comparative analysis of deformable mirrors for ocular adaptive optics.

    PubMed

    Dalimier, Eugenie; Dainty, Chris

    2005-05-30

    We have evaluated the ability of three commercially available deformable mirrors to compensate the aberrations of the eye using a model for aberrations developed by Thibos, Bradley and Hong. The mirrors evaluated were a 37 actuator membrane mirror and 19 actuator piezo mirror (OKO Technologies) and a 35 actuator bimorph mirror (AOptix Inc). For each mirror, Zernike polynomials and typical ocular aberrated wavefronts were fitted with the mirror modes measured using a Twyman-Green interferometer. The bimorph mirror showed the lowest root mean square error, although the 19 actuator piezo device showed promise if extended to more actuators. The methodology can be used to evaluate new deformable mirrors as they become available.

  8. Barstow heliostat mirror glass characterization

    SciTech Connect

    Lind, M.A.; Buckwalter, C.Q.

    1980-09-01

    The technical analysis performed on the special run of low iron float glass procured from the Ford Glass Division for the ten megawatt solar thermal/electric pilot power plant to be constructed at Barstow, California is discussed. The topics that are addressed include the optical properties and the relative durability of the glass. Two optical parameters, solar transmittance and optical flatness, were measured as referenced in the specification and found to be better than the stated tolerances. The average solar transmittance exceeded 0.890 transmittance units. The glass also exhibited optical angular flatness deviations less than +-1.0 mrad as required. Both qualitative and quantitative accelerated weathering tests were performed on the glass in order to compare its durability to other soda lime float glass and alternate composition glasses of interest to the solar community. In both the quantitative leaching experiments and the more qualitative room temperature and elevated temperature water vapor exposure experiments the heliostat glass exhibited the same characteristics as the other soda-lime silicate float glasses. As a final test for mirroring compatability, selected samples of the production run of the glass were sent to four different commercial manufacturers for mirror coating. None of the manufacturers reported any difficulty silvering the glass. Based on the tests performed, the glass meets or exceeds all optical specifications for the Barstow heliostat field.

  9. Explaining mirror-touch synesthesia.

    PubMed

    Ward, Jamie; Banissy, Michael J

    2015-01-01

    Mirror-touch synesthesia (MTS) is the conscious experience of tactile sensations induced by seeing someone else touched. This paper considers two different, although not mutually exclusive, theoretical explanations and, in the final section, considers the relation between MTS and other forms of synesthesia and also other kinds of vicarious perception (e.g., contagious yawning). The Threshold Theory explains MTS in terms of hyper-activity within a mirror system for touch and/or pain. This offers a good account for some of the evidence (e.g., from fMRI) but fails to explain the whole pattern (e.g., structural brain differences outside of this system; performance on some tests of social cognition). The Self-Other Theory explains MTS in terms of disturbances in the ability to distinguish the self from others. This can be construed in terms of over-extension of the bodily self in to others, or as difficulties in the control of body-based self-other representations. In this account, MTS is a symptom of a broader cognitive profile. We suggest this meets the criteria for synesthesia, despite the proximal causal mechanisms remaining largely unknown, and that the tendency to localize vicarious sensory experiences distinguishes it from other kinds of seemingly related phenomena (e.g., non-localized affective responses to observing pain).

  10. ROSAT wide field camera mirrors.

    PubMed

    Willingale, R

    1988-04-15

    The ROSAT wide field camera (WFC) is an XUV telescope operating in the 12-250-eV energy band. The mirror system utilizes Wolter-Schwarzschild type I (WS I) grazing incidence optics with a focal length of 525 mm, comprised of three nested aluminum shells with an outermost diameter of 576 mm providing a geometric aperture area of 456 cm(2). The reflecting surfaces are electroless nickel plated and coated with gold to enhance their reflectivity in the XUV. The mirrors have undergone full aperture optical testing, narrow beam XUV testing, and full aperture XUV testing. Measurements of the reflectivity are compared to theoretical values derived from the optical constants of gold in the XUV range. Analysis of the focused distribution is used to estimate the surface roughness and figuring errors of the polished surfaces. The results are compared to the mechanical metrology data collected during manufacture of the shells and the power spectral density of the reflecting surfaces is found to have a power-law form.

  11. ROSAT Wide Field Camera Mirrors

    NASA Astrophysics Data System (ADS)

    Willingale, R.

    1988-08-01

    The ROSAT wide field camera (WFC) is an XUV telescope operating in the 12-250-eV energy band. The mirror system utilizes Wolter-Schwarzschild type I (WSI) grazing incidence optics with a focal length of 525 mm, comprised of three nested aluminum shells with an outermost diameter of 576 mm providing a geometric aperture area of 456 cm2. The reflecting surfaces are electroless nickel plated and coated with gold to enhance their reflectivity in the XUV. The mirrors have undergone full aperture optical testing, narrow beam XUV testing, and full aperture XUV testing. Measurements of the reflectivity are compared to theoretical values derived from the optical constants of gold in the XUV range. Analysis of the focused distribution is used to estimate the surface roughness and figuring errors of the polished surfaces. The results are compared to the mechanical metrology data collected during manufacture of the shells and the power spectral density of the reflecting surfaces is found to have a power-law form.

  12. FAME: freeform active mirror experiment

    NASA Astrophysics Data System (ADS)

    Aitink-Kroes, Gabby; Agócs, Tibor; Miller, Chris; Black, Martin; Farkas, Szigfrid; Lemared, Sabri; Bettonvil, Felix; Montgomery, David; Marcos, Michel; Jaskó, Attila; van Duffelen, Farian; Challita, Zalpha; Fok, Sandy; Kiaeerad, Fatemeh; Hugot, Emmanuel; Schnetler, Hermine; Venema, Lars

    2016-07-01

    FAME is a four-year project and part of the OPTICON/FP7 program that is aimed at providing a breakthrough component for future compact, wide field, high resolution imagers or spectrographs, based on both Freeform technology, and the flexibility and versatility of active systems. Due to the opening of a new parameter space in optical design, Freeform Optics are a revolution in imaging systems for a broad range of applications from high tech cameras to astronomy, via earth observation systems, drones and defense. Freeform mirrors are defined by a non-rotational symmetry of the surface shape, and the fact that the surface shape cannot be simply described by conicoids extensions, or off-axis conicoids. An extreme freeform surface is a significantly challenging optical surface, especially for UV/VIS/NIR diffraction limited instruments. The aim of the FAME effort is to use an extreme freeform mirror with standard optics in order to propose an integrated system solution for use in future instruments. The work done so far concentrated on identification of compact, fast, widefield optical designs working in the visible, with diffraction limited performance; optimization of the number of required actuators and their layout; the design of an active array to manipulate the face sheet, as well as the actuator design. In this paper we present the status of the demonstrator development, with focus on the different building blocks: an extreme freeform thin face sheet, the active array, a highly controllable thermal actuator array, and the metrology and control system.

  13. Plasma confinement apparatus using solenoidal and mirror coils

    DOEpatents

    Fowler, T. Kenneth; Condit, William C.

    1979-01-01

    A plasma confinement apparatus, wherein multiple magnetic mirror cells are linked by magnetic field lines inside of a solenoid with the mirroring regions for adjacent magnetic mirror cells each formed by a separate mirror coil inside of the solenoid. The magnetic mirror cells may be field reversed.

  14. James Webb Space Telescope (JWST) Primary Mirror Material Selection

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Feinberg, Lee D.; Russell, Kevin; Texter, Scott

    2004-01-01

    The James Webb Space Telescope (JWST) conducted a phase down select process via the Advanced Mirror System Demonstrator (AMSD) project to assess the Technology Readiness Level of various candidate mirror materials. This process culminated in the selection of Beryllium as the JWST primary mirror material. This paper outlines the mirror evaluation process, defines the selection criteria and summarizes the candidate mirror's performances.

  15. Mirrors, Mirrors on the Wall...The Ubiquitous Multiple Reflection Error

    ERIC Educational Resources Information Center

    Lawson, Rebecca

    2012-01-01

    Participants decided when somebody, Janine, could see their face in a horizontal row of adjacent mirrors mounted flat on the same wall. They saw real mirrors and a shop-dummy representing Janine. Such coplanar mirrors reflect different, non-overlapping areas of a scene. However, almost everybody made an unexpected error: they claimed that Janine…

  16. Production of the 4.26 m ZERODUR mirror blank for the Advanced Technology Solar telescope (ATST)

    NASA Astrophysics Data System (ADS)

    Jedamzik, Ralf; Werner, Thomas; Westerhoff, Thomas

    2014-07-01

    The Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST) will be the most powerful solar telescope in the world. It is currently being built by the Association of Universities for Research in Astronomy (AURA) in a height of 3000 m above sea level on the mountain Haleakala of Maui, Hawaii. The primary mirror blank of diameter 4.26 m is made of the extremely low thermal expansion glass ceramic ZERODUR® of SCHOTT AG Advanced Optics. The DKIST primary mirror design is extremely challenging. With a mirror thickness of only 78 to 85 mm it is the smallest thickness ever machined on a mirror of 4.26 m in diameter. Additionally the glassy ZERODUR® casting is one of the largest in size ever produced for a 4 m class ZERODUR® mirror blank. The off axis aspherical mirror surface required sophisticated grinding procedures to achieve the specified geometrical tolerance. The small thickness of about 80 mm required special measures during processing, lifting and transport. Additionally acid etch treatment was applied to the convex back-surface and the conical shaped outer diameter surface to improve the strength of the blank. This paper reports on the challenging tasks and the achievements on the material property and dimensional specification parameter during the production of the 4.26 m ZERODUR® primary mirror blank for AURA.

  17. Tandem mirror magnet system for the mirror fusion test facility

    SciTech Connect

    Bulmer, R.H.; Van Sant, J.H.

    1980-10-14

    The Tandem Mirror Fusion Test Facility (MFTF-B) will be a large magnetic fusion experimental facility containing 22 supercounducting magnets including solenoids and C-coils. State-of-the-art technology will be used extensively to complete this facility before 1985. Niobium titanium superconductor and stainless steel structural cases will be the principle materials of construction. Cooling will be pool boiling and thermosiphon flow of 4.5 K liquid helium. Combined weight of the magnets will be over 1500 tonnes and the stored energy will be over 1600 MJ. Magnetic field strength in some coils will be more than 8 T. Detail design of the magnet system will begin early 1981. Basic requirements and conceptual design are disclosed in this paper.

  18. Figure and Dimension Metrology of Extremely Lightweight X-Ray Mirrors for Space Astronomy Applications

    NASA Technical Reports Server (NTRS)

    Zhang, William W.

    2010-01-01

    The International X-ray Observatory (IXO) is the next major space X-ray observatory, performing both imaging and spectroscopic studies of all kinds of objects in the Universe. It is a collaborative mission of the National Aeronautics and Space Administration of the United States, the European Space Agency, and Japan Aerospace Exploration Agency. It is to be launched into a Sun-Earth L2 orbit in 2021. One of the most challenging aspects of the mission is the construction of a flight mirror assembly capable focusing X-rays in the band of 0.1 to 40 keY with an angular resolution of better than 5 arc-seconds and with an effective collection area of more than 3 sq m. The mirror assembly will consist of approximately 15,000 parabolic and hyperbolic mirror segments, each of which is approximately 200mm by 300mm with a thickness of 0.4mm. The manufacture and qualification of these mirror segments and their integration into the giant mirror assembly have been the objectives of a vigorous technology development program at NASA's Goddard Space Flight Center. Each of these mirror segments needs to be measured and qualified for both optical figure and mechanical dimensions. In this talk, I will describe the technology program with a particular emphasis on a measurement system we are developing to meet those requirements, including the use of coordinate measuring machines, Fizeau interferometers, and custom-designed, and -built null lens. This system is capable of measuring highly off-axis aspherical or cylindrical mirrors with repeatability, accuracy, and speed.

  19. Hemispheric superiority for processing a mirror image.

    PubMed

    Garren, R B; Gehlsen, G M

    1981-04-01

    39 adult subjects were administered a test using tachistoscopic half-field presentations to determine hemispheric dominance and a mirror-tracing task to determine if an hemispheric superiority exists for processing a mirror-image. The results indicate superiority of the nondominant hemisphere for this task.

  20. Corrected mirror systems with double reflection

    NASA Astrophysics Data System (ADS)

    Artyukhina, N. K.; Shkadarevich, A. P.

    2007-03-01

    We propose objectives consisting of two mirrors with central holes for passage of a light beam. The optical layout ensures multiple reflection of rays from both mirrors. We consider several approaches to calculating the design parameters for which three and four aberrations do not occur. The objectives can be used in optical devices operating in the UV and IR regions of the spectrum.

  1. Micromachined deformable mirrors for dynamic wavefront control

    NASA Astrophysics Data System (ADS)

    Bifano, Thomas; Bierden, Paul; Perreault, Julie

    2004-10-01

    The design, manufacture, and testing of optical quality surface micromachined deformable mirrors (DMs) is described. With such mirrors, the shape of the reflective surface can be modified dynami-cally to compensate for optical aberrations and thereby improve image resolution in telescopes or microscopes. Over several years, we have developed microelectromechanical system (MEMS) processing technologies that allow production of optical quality of surface micromachined mirrors. These process steps have been integrated with a commercial foundry process to produce deformable mirrors of unprecedented quality. The devices employ 140 electrostatic actuators. Measurements of their performance detailed in this paper include 2µm of useful stroke, 3nm position repeatability, >90% reflectivity, and flatness better than 20nm RMS. A chemo-mechanical polishing process has been used to improve surface quality of the mirrors, and a gold coating process has been developed to improve the reflectivity without introducing a significant amount of stress in the mirror mem-brane. An ion bombardment technique has been developed to flatten mirrors. These silicon based deformable mirrors have the potential to modulate spatial and temporal features of an optical wave-front, and have applications in imaging, beam-forming, and optical communication systems. Design considerations and performance evaluation of recently fabricated DMs are presented.

  2. LED structure with enhanced mirror reflectivity

    DOEpatents

    Bergmann, Michael; Donofrio, Matthew; Heikman, Sten; Schneider, Kevin S; Haberern, Kevin W; Edmond, John A

    2014-04-01

    Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

  3. Naive Optics: Acting on Mirror Reflections

    ERIC Educational Resources Information Center

    Hecht, Heiko; Bertamini, Marco; Gamer, Matthias

    2005-01-01

    It is known that naive observers have striking misconceptions about mirror reflections. In 5 experiments, this article systematically extends the findings to graphic stimuli, to interactive visual tasks, and finally to tasks involving real mirrors. The results show that the perceptual knowledge of nonexpert adults is far superior to their…

  4. Foil Panel Mirrors for Nonimaging Applications

    NASA Technical Reports Server (NTRS)

    Kuyper, D. J.; Castillo, A. A.

    1984-01-01

    Large durable, lightweight mirrors made by bonding thick aluminum foil to honeycomb panels or other rigid, flat backings. Mirrors suitable for use as infrared shields, telescope doors, solar-furnance doors, advertising displays, or other reflectors that require low thermal emissivity and high specularity but do not require precise surface figure necessary for imaging.

  5. Three-point spherical mirror mount

    DOEpatents

    Cutburth, Ronald W.

    1990-01-01

    A three-point spherical mirror mount for use with lasers is disclosed. The improved mirror mount is adapted to provide a pivot ring having an outer surface with at least three spaced apart mating points to engage an inner spherical surface of a support housing.

  6. Unbroken Mirror Neurons in Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Fan, Yang-Teng; Decety, Jean; Yang, Chia-Yen; Liu, Ji-Lin; Cheng, Yawei

    2010-01-01

    Background: The "broken mirror" theory of autism, which proposes that a dysfunction of the human mirror neuron system (MNS) is responsible for the core social and cognitive deficits in individuals with autism spectrum disorders (ASD), has received considerable attention despite weak empirical evidence. Methods: In this electroencephalographic…

  7. Three-point spherical mirror mount

    DOEpatents

    Cutburth, R.W.

    1984-01-23

    A three-point spherical mirror mount for use with lasers is disclosed. The improved mirror mount is adapted to provide a pivot ring having an outer surface with at least three spaced apart mating points to engage an inner spherical surface of a support housing.

  8. Technology for large tandem mirror experiments

    SciTech Connect

    Thomassen, K.I.

    1980-09-04

    Construction of a large tandem mirror (MFTF-B) will soon begin at Lawrence Livermore National Laboratory (LLNL). Designed to reach break-even plasma conditions, the facility will significantly advance the physics and technology of magnetic-mirror-based fusion reactors. This paper describes the objectives and the design of the facility.

  9. Stirling machine operating experience

    NASA Technical Reports Server (NTRS)

    Ross, Brad; Dudenhoefer, James E.

    1991-01-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that Stirling machines are capable of reliable and lengthy lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and were not expected to operate for any lengthy period of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered.

  10. Women, Men, and Machines.

    ERIC Educational Resources Information Center

    Form, William; McMillen, David Byron

    1983-01-01

    Data from the first national study of technological change show that proportionately more women than men operate machines, are more exposed to machines that have alienating effects, and suffer more from the negative effects of technological change. (Author/SSH)

  11. Optical properties of relativistic plasma mirrors

    PubMed Central

    Vincenti, H.; Monchocé, S.; Kahaly, S.; Bonnaud, G.; Martin, Ph.; Quéré, F.

    2014-01-01

    The advent of ultrahigh-power femtosecond lasers creates a need for an entirely new class of optical components based on plasmas. The most promising of these are known as plasma mirrors, formed when an intense femtosecond laser ionizes a solid surface. These mirrors specularly reflect the main part of a laser pulse and can be used as active optical elements to manipulate its temporal and spatial properties. Unfortunately, the considerable pressures exerted by the laser can deform the mirror surface, unfavourably affecting the reflected beam and complicating, or even preventing, the use of plasma mirrors at ultrahigh intensities. Here we derive a simple analytical model of the basic physics involved in laser-induced deformation of a plasma mirror. We validate this model numerically and experimentally, and use it to show how such deformation might be mitigated by appropriate control of the laser phase. PMID:24614748

  12. DAMA annual modulation and mirror Dark Matter

    NASA Astrophysics Data System (ADS)

    Cerulli, R.; Villar, P.; Cappella, F.; Bernabei, R.; Belli, P.; Incicchitti, A.; Addazi, A.; Berezhiani, Z.

    2017-02-01

    The DAMA experiment using ultra low background NaI(Tl) crystal scintillators has measured an annual modulation effect in the keV region which satisfies all the peculiarities of an effect induced by Dark Matter particles. In this paper we analyze this annual modulation effect in terms of mirror Dark Matter, an exact duplicate of ordinary matter from parallel hidden sector, which chemical composition is dominated by mirror helium while it can also contain significant fractions of heavier elements as Carbon and Oxygen. Dark mirror atoms are considered to interact with the target nuclei in the detector via Rutherford-like scattering induced by kinetic mixing between mirror and ordinary photons, both being massless. In the present analysis we consider various possible scenarios for the mirror matter chemical composition. For all the scenarios, the relevant ranges for the kinetic mixing parameter have been obtained taking also into account various existing uncertainties in nuclear and particle physics quantities.

  13. Optical data processing using paraboloidal mirror segments

    NASA Technical Reports Server (NTRS)

    Husain-Abidi, A. S. (Inventor)

    1973-01-01

    An optical data processing system using paraboloidal reflecting surfaces is disclosed. In the preferred embodiment the paraboloidal reflecting surfaces are segments of a paraboloidal mirror. A source of coherent light is in the focal plane of the first paraboloidal mirror segment which collimates the beam and reflects it toward a second paraboloidal mirror surface. The information to be analyzed, on a transparency for example, is placed in the collimated beam. The beam is reflected from the second paraboloidal mirror segment and focused on a Fourier transform plane. A photon detector could be placed in the Fourier transform plane or suitable spatial filters, with the filtered beam then being reflected from a third paraboloidal mirror segment to be focused on a reconstruction plane.

  14. Optical properties of relativistic plasma mirrors.

    PubMed

    Vincenti, H; Monchocé, S; Kahaly, S; Bonnaud, G; Martin, Ph; Quéré, F

    2014-03-11

    The advent of ultrahigh-power femtosecond lasers creates a need for an entirely new class of optical components based on plasmas. The most promising of these are known as plasma mirrors, formed when an intense femtosecond laser ionizes a solid surface. These mirrors specularly reflect the main part of a laser pulse and can be used as active optical elements to manipulate its temporal and spatial properties. Unfortunately, the considerable pressures exerted by the laser can deform the mirror surface, unfavourably affecting the reflected beam and complicating, or even preventing, the use of plasma mirrors at ultrahigh intensities. Here we derive a simple analytical model of the basic physics involved in laser-induced deformation of a plasma mirror. We validate this model numerically and experimentally, and use it to show how such deformation might be mitigated by appropriate control of the laser phase.

  15. Replicated Electro-Formed Nickel Alloy Mirror

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. Dr. Joe Ritter examines a replicated electro-formed nickel-alloy mirror which exemplifies the improvements in mirror fabrication techniques, with benefits such as dramtic weight reduction that have been achieved at the Marshall Space Flight Center's Space Optics Manufacturing Technology Center (SOMTC).

  16. Mirror Neurons through the Lens of Epigenetics

    PubMed Central

    Ferrari, Pier F.; Tramacere, Antonella; Simpson, Elizabeth A.; Iriki, Atsushi

    2013-01-01

    The consensus view in mirror neuron research is that mirror neurons comprise a uniform, stable execution-observation matching system. In this article, we argue that, in light of recent evidence, this is, at best, an incomplete and oversimplified view of mirror neurons, whose activity is actually quite variable and more plastic than previously theorized. We propose an epigenetic account for understanding developmental changes in sensorimotor systems, including variations in mirror neuron activity. Although extant associative and genetic accounts fail to consider the complexity of genetic and non-genetic interactions, we propose a new Evo-Devo perspective, which predicts that environmental differences early in development, or through sensorimotor training, should produce variations in mirror neuron response patterns, tuning them to the social environment. PMID:23953747

  17. The Iowa wave machines

    NASA Astrophysics Data System (ADS)

    Daffron, John D.; Greenslade, Thomas B.; Stille, Dale

    2010-03-01

    Wave machines are a staple of demonstration lectures, and a good pair of wave machines can make the idea of transverse and longitudinal waves clearly evident to students. The demonstration apparatus collection of the University of Iowa contains examples of transverse and longitudinal wave machines that will be of interest to readers of The Physics Teacher. These machines probably date from about 1925 and may have been locally produced. You too can build them.

  18. [Motion control of moving mirror based on fixed-mirror adjustment in FTIR spectrometer].

    PubMed

    Li, Zhong-bing; Xu, Xian-ze; Le, Yi; Xu, Feng-qiu; Li, Jun-wei

    2012-08-01

    The performance of the uniform motion of the moving mirror, which is the only constant motion part in FTIR spectrometer, and the performance of the alignment of the fixed mirror play a key role in FTIR spectrometer, and affect the interference effect and the quality of the spectrogram and may restrict the precision and resolution of the instrument directly. The present article focuses on the research on the uniform motion of the moving mirror and the alignment of the fixed mirror. In order to improve the FTIR spectrometer, the maglev support system was designed for the moving mirror and the phase detection technology was adopted to adjust the tilt angle between the moving mirror and the fixed mirror. This paper also introduces an improved fuzzy PID control algorithm to get the accurate speed of the moving mirror and realize the control strategy from both hardware design and algorithm. The results show that the development of the moving mirror motion control system gets sufficient accuracy and real-time, which can ensure the uniform motion of the moving mirror and the alignment of the fixed mirror.

  19. Durable silver coating for mirrors

    DOEpatents

    Wolfe, Jesse D.; Thomas, Norman L.

    2000-01-01

    A durable multilayer mirror includes reflective layers of aluminum and silver and has high reflectance over a broad spectral range from ultraviolet to visible to infrared. An adhesion layer of a nickel and/or chromium alloy or nitride is deposited on an aluminum surface, and a thin layer of silver is then deposited on the adhesion layer. The silver layer is protected by a passivation layer of a nickel and/or chromium alloy or nitride and by one or more durability layers made of metal oxides and typically a first layer of metal nitride. The durability layers may include a composite silicon aluminum nitride and an oxinitride transition layer to improve bonding between nitride and oxide layers.

  20. Compact active mirror laser (CAMIL)

    NASA Astrophysics Data System (ADS)

    Vetrovec, John

    2002-03-01

    This work presents concept and scaling considerations for a solid-state laser with a gain medium disk operating in the active mirror mode. The disk is of composite construction formed by bonding undoped optical medium to the peripheral edges of a gain medium disk. Pump diode arrays are placed around the perimeter of the composite disk and pump light is injected into the undoped edge. With proper choice of lasant doping, diode placement and diode divergence, a uniform laser gain can be achieved across large portions of the disk. To mitigate thermal deformations, the gain medium disk is pressure-clamped to a rigid, cooled substrate. Effective reduction of thermo-optical distortions makes this laser suitable for operation at high-average power.

  1. Mirror Modes in the Heliosheath

    SciTech Connect

    Tsurutani, B. T.; Guarnieri, F. L.; Echer, E. E.; Lakhina, G. S.; Verkhoglyadova, O. P.

    2011-01-04

    Mirror mode (MM) structures are identified in the Voyager 1 heliosheath magnetic field data. Their characteristics are: (1) quasiperiodic structures with a typical scale size of {approx}57 {rho}{sub p}(proton gyroradii), (2) little or no angular changes across the structures ({approx}3 deg. longitude and {approx}3 deg. latitude), and (3) a lack of sharp boundaries at the magnetic dip edges. It is proposed that the pickup of interstellar neutrals in the upstream region of the termination shock (TS) is the likely cause of MM instability during intervals when the IMF is nearly orthogonal to the solar wind flow direction. Concomitant (quasiperpendicular) shock compression of the MM structures at the TS and additional injection of pickup ions (PUIs) throughout the heliosheath will enhance MM growth.

  2. Deformable Mirror Materials Issue Assessment

    SciTech Connect

    Rudd, R E

    2008-05-27

    It was a pleasure to speak with you and Dr. Olivier Guyon about your project to develop a coronagraph and in particular about materials science considerations in the development of the deformable mirror (DM) for the coronagraph. The coronagraph application will demand more of a DM than previous applications with regard to precision, and since the characterization and modeling tools are currently under development, you asked me to comment on materials issues that might impact the DM design and testing. I have not conducted research on this question, and my own research on modeling MEMS has not included DM systems. I am only in a position to discuss some general considerations that may help in developing a research plan for the DM system. As I understand it, the relevant points about the DM system are as follows. The DM surface needs to be positioned to less than 1 {angstrom} RMS of the desired shape, and be stable to 0.3 {angstrom} RMS for an hour. In the ultimate application in space the stability requirements may be greater. For example, the DM shape can be set using a bright star and then allow the coronagraph to be turned to a dim star to collect data for several hours, counting on the mirror shape to be stable. The DM is made of a polysilicon membrane coated with one or more metal layers for the reflective surface and actuated by 32x32 or 64x64 electrostatic actuators on the back side. The uncertainty in the position of any one actuator should be at the few-picometer level or less averaged over the 300-{micro}m region of the actuator. Currently, experiments are conducted that can characterize the surface shape to the 1 nm level, and it is anticipated that the experiments will be able to characterize the shape at the sub-Angstrom level but not in the immediate future. Regarding stability, under relatively large deformations (10's of nm), the DM mirror surface shows no hysteresis at the measurable nm level. Let me begin by saying that I am not aware of any

  3. Toward a large lightweight mirror for AO: development of a 1m Ni coated CFRP mirror

    NASA Astrophysics Data System (ADS)

    Thompson, S. J.; Doel, A. P.; Brooks, D.; Strangwood, M.

    2008-07-01

    We present our recent developments towards the construction of a large, thin, single-piece mirror for adaptive optics (AO). Our current research program aims to have completed fabrication and testing of a 1m diameter, nickel coated carbon-fibre reinforced cyanate ester resin mirror by the last quarter of 2009. This composite mirror material is being developed to provide a lightweight and robust alternative to thin glass shell mirrors, with the challenge of future large deformable mirrors such as the 2.5m M4 on the E-ELT in mind. A detailed analysis of the material properties of test mirror samples is being performed at the University of Birmingham (UK), the first results of which are discussed and presented here. We discuss the project progress achieved so far, including fabrication of the 1m flat moulds for the replication process, manufacturing and testing methods for 20 cm diameter sample mirrors and system simulations.

  4. Dreams that mirror the session.

    PubMed

    Civitarese, Giuseppe

    2006-06-01

    Dreams in which the analyst appears undisguised almost always depict violations of the setting. Often experienced as special, epiphanic moments, they give a glimpse of an intense, emotional reaction to traumatogenic or otherwise significant events that have occurred during the session or in the most recent previous ones. Probably, the essential aspect of these dreams can be found in the 'form of their content'. This may be paralleled by the narrative technique of mise en abyme or mirror-text. The dream appears as a story within the main story and the scene of the analysis is reflected anti-illusionistically. The fictional structure of the setting is emphasized. Its theatrical self-consciousness quality is revealed at its best. The author postulates that the transformative therapeutic value of these dreams derives from denouncing the referential illusion of 'concrete reality' and of 'what really happened'. For the analysand, they are an effective (i.e. emotionally intense) opportunity to discover the spatial articulations and the staggering refractions of the inside/outside, the textual/extra-textual, the psychic reality/material reality. In the continual comings and goings from one term to another, the work of symbolization is reactivated and the subject is constructed. Dreams that mirror the session, from this point of view, provide a model for conceptualizing the analytic work, and their significance goes beyond the specific phenomena referred to. A clinical case is given, in which some of one patient's dreams are considered as they occurred over a short period. In one of them, the dream-within-a-dream phenomenon is present.

  5. Relation between Radial and Axial Losses in Tandem Mirrors

    NASA Astrophysics Data System (ADS)

    Pratt, J.; Horton, W.; Berk, H. L.

    2006-04-01

    The tandem mirror still remains a potentially attractive magnetic confinement geometry. The absence of toroidal curvature and internal plasma parallel current gives the system strongly favorable stability. Additionally, GAMMA-10 experimental results demonstrate that sheared rotation can suppress turbulent radial losses. For an MHD stable system, we investigate the interplay between drift wave (ITG, ETG and Bohm) radial transport and axial losses. Using empirical energy confinement scaling laws from large ITER and ISS databases as upper bounds on the radial loss rates, we simulate radial transport using a transport barrier dynamics (TBD) code. Simulations are carried out for a machine of volume 212 m^3 (central cell length/radius 30 m/1.5 m) with central cell field 3 T. ITER stores 7022 MJ of energy in the toroidal magnetic field; in our tandem mirror design this energy is reduced to 954 MJ. Our simulations show that high core temperatures result in long Pastukhov loss times; drift wave radial transport dominates, except at the plasma edge, where pitch angle scattering causes losses.

  6. Current Status of the Gasdynamic Mirror Fusion Propulsion Experiment

    NASA Technical Reports Server (NTRS)

    Emrich, William J., Jr.

    2002-01-01

    Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). An experimental GDM device has been constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. An initial shakedown of the device is currently underway with initial experiments slated to occur in late 2001. This device would operate at much higher plasma densities and with much larger L/D ratios than previous mirror machines. The high L/D ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. The high plasma density results in the plasma behaving much more like a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with 'loss cone' microinstabilities. The device has been constructed to allow a considerable degree of flexibility in its configuration thus permitting the experiment to grow over time without necessitating a great deal of additional fabrication.

  7. Archetypal-Imaging and Mirror-Gazing

    PubMed Central

    Caputo, Giovanni B.

    2013-01-01

    Mirrors have been studied by cognitive psychology in order to understand self-recognition, self-identity, and self-consciousness. Moreover, the relevance of mirrors in spirituality, magic and arts may also suggest that mirrors can be symbols of unconscious contents. Carl G. Jung investigated mirrors in relation to the unconscious, particularly in Psychology and Alchemy. However, the relationship between the conscious behavior in front of a mirror and the unconscious meaning of mirrors has not been clarified. Recently, empirical research found that gazing at one’s own face in the mirror for a few minutes, at a low illumination level, produces the perception of bodily dysmorphic illusions of strange-faces. Healthy observers usually describe huge distortions of their own faces, monstrous beings, prototypical faces, faces of relatives and deceased, and faces of animals. In the psychiatric population, some schizophrenics show a dramatic increase of strange-face illusions. They can also describe the perception of multiple-others that fill the mirror surface surrounding their strange-face. Schizophrenics are usually convinced that strange-face illusions are truly real and identify themselves with strange-face illusions, diversely from healthy individuals who never identify with them. On the contrary, most patients with major depression do not perceive strange-face illusions, or they perceive very faint changes of their immobile faces in the mirror, like death statues. Strange-face illusions may be the psychodynamic projection of the subject’s unconscious archetypal contents into the mirror image. Therefore, strange-face illusions might provide both an ecological setting and an experimental technique for “imaging of the unconscious”. Future researches have been proposed. PMID:25379264

  8. Mirror Figuring Techniques of Sir William Herschel

    NASA Astrophysics Data System (ADS)

    Albin, E. F.

    2004-05-01

    Between the years 1773 to 1818, Sir William Herschel constructed dozens of speculum telescope mirrors, with diameters ranging from 6 - 48 inches. Very little, if any, detailed information has ever been published on the specifics of his mirror figuring efforts. The reason for this certainly relates to his desire to closely guard mirror production trade secrets. Upon Herschel's death, all telescope-making documents were passed on to his only son, Sir John Herschel. These materials are now in the possession of the British RAS and primarily consist of: a) a four volume series entitled "Experiments on the Construction of Specula," b) a 129 page treaty called "On the Construction of Specula," and c) a 179 page manuscript entitled "Results of Experiments on the Construction of Mirrors." It is suggested that publication was further delayed and then eventually abandoned due to silver-coated glass mirrors coming into favor. A recent investigation by the author, of the unpublished manuscripts on the construction of specula, suggests that Herschel's mirror figuring techniques did not involve any guess work; in fact, his methods were highly refined -- never leaving to chance the evolution of a spherical surface into the required paraboloid. At the heart of Herschel's figuring techniques were a series of aperture diaphragms (similar to the Couder masks used by modern telescope makers) that were placed over the mirror, which allowed for the precise determination of its curvature at various predefined zones. With this information, Herschel was able to vary his figuring strokes with his polishing tool accordingly. In addition, all mirrors were subsequently "star tested," sometimes with aperture diaphragms in place, allowing for field examination of the mirror's "distinctness" or performance. Double stars and the planet Saturn were favorite targets used to analyze and then correct a mirror's figure.

  9. Large thin adaptive x-ray mirrors

    NASA Astrophysics Data System (ADS)

    Doel, Peter; Atkins, Carolyn; Thompson, Samantha; Brooks, David; Yao, Jun; Feldman, Charlotte; Willingale, Richard; Button, Tim; Zhang, Dou; James, Ady

    2007-09-01

    This paper describes the progress made in a proof of concept study and recent results of a research program into large active x-ray mirrors that is part of the UK Smart X-ray Optics project. The ultimate aim is to apply the techniques of active/adaptive optics to the next generation of nested shell astronomical X-ray space telescopes. A variety of deformable mirror technologies are currently available, the most promising of which for active X-ray mirrors are probably unimorph and bimorph piezoelectric mirrors. In this type of mirror one or more sheets of piezoelectric material are bonded to or coated with a passive reflective layer. On the back or between the piezoceramic layer/layers are series of electrodes. Application of an electric field causes the piezoelectric material to undergo local deformation thus changing the mirror shape. Starting in 2005 a proof of concept active mirror research program has been undertaken. This work included modelling and development of actively controlled thin shell mirrors. Finite element models of piezo-electric actuated mirrors have been developed and verified against experimental test systems. This has included the modelling and test of piezo-electric hexagonal unimorph segments. Various actuator types and low shrinkage conductive bonding methods have been investigated and laboratory tests of the use of piezo-electric actuators to adjust the form of an XMM-Newton space telescope engineering model mirror shell have been conducted and show that movement of the optics at the required level is achievable. Promising technological approaches have been identified including moulded piezo-ceramics and piezo-electrics fibre bundles.

  10. Archetypal-imaging and mirror-gazing.

    PubMed

    Caputo, Giovanni B

    2014-03-01

    Mirrors have been studied by cognitive psychology in order to understand self-recognition, self-identity, and self-consciousness. Moreover, the relevance of mirrors in spirituality, magic and arts may also suggest that mirrors can be symbols of unconscious contents. Carl G. Jung investigated mirrors in relation to the unconscious, particularly in Psychology and Alchemy. However, the relationship between the conscious behavior in front of a mirror and the unconscious meaning of mirrors has not been clarified. Recently, empirical research found that gazing at one's own face in the mirror for a few minutes, at a low illumination level, produces the perception of bodily dysmorphic illusions of strange-faces. Healthy observers usually describe huge distortions of their own faces, monstrous beings, prototypical faces, faces of relatives and deceased, and faces of animals. In the psychiatric population, some schizophrenics show a dramatic increase of strange-face illusions. They can also describe the perception of multiple-others that fill the mirror surface surrounding their strange-face. Schizophrenics are usually convinced that strange-face illusions are truly real and identify themselves with strange-face illusions, diversely from healthy individuals who never identify with them. On the contrary, most patients with major depression do not perceive strange-face illusions, or they perceive very faint changes of their immobile faces in the mirror, like death statues. Strange-face illusions may be the psychodynamic projection of the subject's unconscious archetypal contents into the mirror image. Therefore, strange-face illusions might provide both an ecological setting and an experimental technique for "imaging of the unconscious". Future researches have been proposed.

  11. Lightweight deformable mirrors for future space telescopes

    NASA Astrophysics Data System (ADS)

    Patterson, Keith

    This thesis presents a concept for ultra-lightweight deformable mirrors based on a thin substrate of optical surface quality coated with continuous active piezopolymer layers that provide modes of actuation and shape correction. This concept eliminates any kind of stiff backing structure for the mirror surface and exploits micro-fabrication technologies to provide a tight integration of the active materials into the mirror structure, to avoid actuator print-through effects. Proof-of-concept, 10-cm-diameter mirrors with a low areal density of about 0.5 kg/m2 have been designed, built and tested to measure their shape-correction performance and verify the models used for design. The low cost manufacturing scheme uses replication techniques, and strives for minimizing residual stresses that deviate the optical figure from the master mandrel. It does not require precision tolerancing, is lightweight, and is therefore potentially scalable to larger diameters for use in large, modular space telescopes. Other potential applications for such a laminate could include ground-based mirrors for solar energy collection, adaptive optics for atmospheric turbulence, laser communications, and other shape control applications. The immediate application for these mirrors is for the Autonomous Assembly and Reconfiguration of a Space Telescope (AAReST) mission, which is a university mission under development by Caltech, the University of Surrey, and JPL. The design concept, fabrication methodology, material behaviors and measurements, mirror modeling, mounting and control electronics design, shape control experiments, predictive performance analysis, and remaining challenges are presented herein. The experiments have validated numerical models of the mirror, and the mirror models have been used within a model of the telescope in order to predict the optical performance. A demonstration of this mirror concept, along with other new telescope technologies, is planned to take place during

  12. Mirror neurons: from origin to function.

    PubMed

    Cook, Richard; Bird, Geoffrey; Catmur, Caroline; Press, Clare; Heyes, Cecilia

    2014-04-01

    This article argues that mirror neurons originate in sensorimotor associative learning and therefore a new approach is needed to investigate their functions. Mirror neurons were discovered about 20 years ago in the monkey brain, and there is now evidence that they are also present in the human brain. The intriguing feature of many mirror neurons is that they fire not only when the animal is performing an action, such as grasping an object using a power grip, but also when the animal passively observes a similar action performed by another agent. It is widely believed that mirror neurons are a genetic adaptation for action understanding; that they were designed by evolution to fulfill a specific socio-cognitive function. In contrast, we argue that mirror neurons are forged by domain-general processes of associative learning in the course of individual development, and, although they may have psychological functions, they do not necessarily have a specific evolutionary purpose or adaptive function. The evidence supporting this view shows that (1) mirror neurons do not consistently encode action "goals"; (2) the contingency- and context-sensitive nature of associative learning explains the full range of mirror neuron properties; (3) human infants receive enough sensorimotor experience to support associative learning of mirror neurons ("wealth of the stimulus"); and (4) mirror neurons can be changed in radical ways by sensorimotor training. The associative account implies that reliable information about the function of mirror neurons can be obtained only by research based on developmental history, system-level theory, and careful experimentation.

  13. Cable-Twisting Machine

    NASA Technical Reports Server (NTRS)

    Kurnett, S.

    1982-01-01

    New cable-twisting machine is smaller and faster than many production units. Is useful mainly in production of short-run special cables. Already-twisted cable can be fed along axis of machine. Faster operation than typical industrial cable-twisting machines possible by using smaller spools of wire.

  14. Apprentice Machine Theory Outline.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational-Technical Schools.

    This volume contains outlines for 16 courses in machine theory that are designed for machine tool apprentices. Addressed in the individual course outlines are the following topics: basic concepts; lathes; milling machines; drills, saws, and shapers; heat treatment and metallurgy; grinders; quality control; hydraulics and pneumatics;…

  15. Impedance Matched to Vacuum, Invisible Edge, Diffraction Suppressed Mirror

    NASA Technical Reports Server (NTRS)

    Hagopian, John G. (Inventor); Roman, Patrick A. (Inventor); Shiri, Sharham (Inventor); Wollack, Edward J. (Inventor)

    2015-01-01

    Diffraction suppressed mirrors having an invisible edge are disclosed for incident light at both targeted wavelengths and broadband incident light. The mirrors have a first having at least one discontiguous portion having a plurality of nanostructured apertures. The discontiguous mirror portion impedance matches a relatively high impedance portion of the mirror to a relatively low impedance portion of the mirror, thereby reducing the diffraction edge effect otherwise present in a conventional mirror.

  16. Double arch mirror study. Part 3: Fabrication and test report

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    A method of mounting a cryogenically cooled, lightweight, double arch, glass mirror was developed for infrared, astronomical telescopes such as the Space Infrared Telescope Facility (SIRTF). A 50 cm, fused silica mirror which was previously fabricated was modified for use with a new mount configuration. This mount concept was developed. The modification of the mirror, the fabrication of the mirror mount, and the room temperature testing of the mounted mirror are reported. A design for a SIRTF class primary mirror is suggested.

  17. Fabrication of metal mirror modules for snap-together VIS telescopes

    NASA Astrophysics Data System (ADS)

    Beier, Matthias; Hartung, Johannes; Kinast, Jan; Gebhardt, Andreas; Burmeister, Frank; Zeitner, Uwe D.; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

    2015-10-01

    The assembly effort of an optical system naturally relies on the degrees of freedom and the maximum allowable tolerances each optical surface introduces into the overall budget. Snap-together approaches traditionally can be regarded as attractive solutions for IR systems having moderate tolerances, where the required precision is achieved by simultaneously machining optical surfaces and mounting interfaces in a single machine setup. Recent improvements in manufacturing and metrology enable a transfer of the assembly approach to shorter wavelength applications, where sub-aperture figuring techniques are used in combination with suitable amorphous polishing layers to achieve the increased requirements on figure and finish. A further decrease of the assembly effort is gained by machining several optical surfaces on common mechanical substrates and fixing the relative position with uncertainties as low as the machine precision. The article presents the fabrication of large electroless nickel coated aluminum mirror modules having two functional freeform surfaces and references for metrology and system integration. The modules are part of an all metal anamorphic imaging telescope operating in the visual spectral range. Presented methods open up a rapid and reliable assembly of metal mirror based VIS telescopes to be used in ground and space based astronomy or remote sensing applications.

  18. Clamping in Boltzmann machines.

    PubMed

    Livesey, M

    1991-01-01

    A certain assumption that appears in the proof of correctness of the standard Boltzmann machine learning procedure is investigated. The assumption, called the clamping assumption, concerns the behavior of a Boltzmann machine when some of its units are clamped to a fixed state. It is argued that the clamping assumption is essentially an assertion of the time reversibility of a certain Markov chain underlying the behavior of the Boltzmann machine. As such, the clamping assumption is generally false, though it is certainly true of the Boltzmann machines themselves. The author also considers how the concept of the Boltzmann machine may be generalized while retaining the validity of the clamping assumption.

  19. Fabrication of high precision metallic freeform mirrors with magnetorheological finishing (MRF)

    NASA Astrophysics Data System (ADS)

    Beier, Matthias; Scheiding, Sebastian; Gebhardt, Andreas; Loose, Roman; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

    2013-09-01

    The fabrication of complex shaped metal mirrors for optical imaging is a classical application area of diamond machining techniques. Aspherical and freeform shaped optical components up to several 100 mm in diameter can be manufactured with high precision in an acceptable amount of time. However, applications are naturally limited to the infrared spectral region due to scatter losses for shorter wavelengths as a result of the remaining periodic diamond turning structure. Achieving diffraction limited performance in the visible spectrum demands for the application of additional polishing steps. Magnetorheological Finishing (MRF) is a powerful tool to improve figure and finish of complex shaped optics at the same time in a single processing step. The application of MRF as a figuring tool for precise metal mirrors is a nontrivial task since the technology was primarily developed for figuring and finishing a variety of other optical materials, such as glasses or glass ceramics. In the presented work, MRF is used as a figuring tool for diamond turned aluminum lightweight mirrors with electroless nickel plating. It is applied as a direct follow-up process after diamond machining of the mirrors. A high precision measurement setup, composed of an interferometer and an advanced Computer Generated Hologram with additional alignment features, allows for precise metrology of the freeform shaped optics in short measuring cycles. Shape deviations less than 150 nm PV / 20 nm rms are achieved reliably for freeform mirrors with apertures of more than 300 mm. Characterization of removable and induced spatial frequencies is carried out by investigating the Power Spectral Density.

  20. Design of bipod flexures for space mirror

    NASA Astrophysics Data System (ADS)

    Chu, Chang-bo; Li, Ying-cai; Chai, Wen-yi; Fan, Xue-wu

    2011-08-01

    Bipod flexures are used in many high-precision space mirror mount applications. The flexures are used to provide moment isolation for the mirror to minimize surface figure distortion resulting from mount assembly error or distortion of the mount temperature-change-induced. In this paper, we developed a bipod flexure for the Zerodur primary mirror with diameter 520 mm and thickness 70 mm. The characteristic of the bipod flexure is the two-strip flexure on the top and bottom of each leg. By those, the bending stress in mirror resulting from the mount assembly is remarkably reduced. Thanking to a semi-open structure with small mouth and big stomach in the back and a six parts symmetrical honeycomb structure for the primary mirror, using the FEA (Finite Element Analysis) method we analyze that how the axial and circumferential locations of the three bipod flexures impact mirror surface figure and gain the better result after optimization. In the design of the detail bipod flexures, thickness of the blade is analyzed and compared; also we achieve an optimization design. The two results demonstrate that the bipod flexures could keep the precision of the mirror surface figure under the load of external force and thermal constraints and meanwhile they could keep stability of structure.

  1. A Deployable Primary Mirror for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Phelps, James E.; Dyer, Jack E.; Caudle, David A.; Tam, Anthony; Escobedo, Javier; Kasl, Eldon P.

    1999-01-01

    NASA Langley Research Center, Composite Optics, Inc., and Nyma/ADF have developed jointly a deployable primary mirror for space telescopes that combines over five years of research on deployment of optical-precision structures and over ten years of development of fabrication techniques for optical-precision composite mirror panels and structures. The deployable mirror is directly applicable to a broad class of non-imaging "lidar" (light direction a nd ranging) telescopes whose figure-error requirements are in the range of one to ten microns RMS. Furthermore, the mirror design can be readily modified to accommodate imaging-quality reflector panels and active panel-alignment control mechanisms for application to imaging telescopes. The present paper: 1) describes the deployable mirror concept; 2) explains the status of the mirror development; and 3) provides some technical specifications for a 2.55- m-diameter, proof-of-concept mirror. Keywords: precision deployment, hinge joint, latch joint, deployable structures, fabrication, space telescopes, optical instruments, microdynamics.

  2. Mirror neurons: functions, mechanisms and models.

    PubMed

    Oztop, Erhan; Kawato, Mitsuo; Arbib, Michael A

    2013-04-12

    Mirror neurons for manipulation fire both when the animal manipulates an object in a specific way and when it sees another animal (or the experimenter) perform an action that is more or less similar. Such neurons were originally found in macaque monkeys, in the ventral premotor cortex, area F5 and later also in the inferior parietal lobule. Recent neuroimaging data indicate that the adult human brain is endowed with a "mirror neuron system," putatively containing mirror neurons and other neurons, for matching the observation and execution of actions. Mirror neurons may serve action recognition in monkeys as well as humans, whereas their putative role in imitation and language may be realized in human but not in monkey. This article shows the important role of computational models in providing sufficient and causal explanations for the observed phenomena involving mirror systems and the learning processes which form them, and underlines the need for additional circuitry to lift up the monkey mirror neuron circuit to sustain the posited cognitive functions attributed to the human mirror neuron system.

  3. Laser cleaning of ITER's diagnostic mirrors

    NASA Astrophysics Data System (ADS)

    Skinner, C. H.; Gentile, C. A.; Doerner, R.

    2012-10-01

    Practical methods to clean ITER's diagnostic mirrors and restore reflectivity will be critical to ITER's plasma operations. We report on laser cleaning of single crystal molybdenum mirrors coated with either carbon or beryllium films 150 - 420 nm thick. A 1.06 μm Nd laser system provided 220 ns pulses at 8 kHz with typical power densities of 1-2 J/cm^2. The laser beam was fiber optically coupled to a scanner suitable for tokamak applications. The efficacy of mirror cleaning was assessed with a new technique that combines microscopic imaging and reflectivity measurements [1]. The method is suitable for hazardous materials such as beryllium as the mirrors remain sealed in a vacuum chamber. Excellent restoration of reflectivity for the carbon coated Mo mirrors was observed after laser scanning under vacuum conditions. For the beryllium coated mirrors restoration of reflectivity has so far been incomplete and modeling indicates that a shorter duration laser pulse is needed. No damage of the molybdenum mirror substrates was observed.[4pt][1] C.H. Skinner et al., Rev. Sci. Instrum. at press.

  4. Stressed mirror annular polishing for scale-down TMT primary segments

    NASA Astrophysics Data System (ADS)

    Li, Xinnan; Jiang, Zibo; Gong, Xuefei; Zhang, Haiying; Chen, Kunxing; Zheng, Yi; Li, Bo; Yu, Binbin; Xu, Chen; Ji, Bo; Xu, Qiuyun

    2016-07-01

    A new type Stressed Mirror Polishing method using annular polishing machine is developed in NIAOT. It provides good efficiency for the massive production of off-axis segments for the extremely large telescope because 3 or more pieces of segment can be polished simultaneously on a AP machine. With an annular polishing machine with 3.6m diameter, two scale-down TMT segments have been polished. Both 2 segments are Φ1100mm in diameter, with the vertex radius of curvature of 60m and aspheric constant K=-1.000953. The off-axis distances (OAD) are 8m and 12m respectively. After SMAP process, the acceptable surface accuracy can be reached, which is 1.12μm/0.23μm of PV/RMS value for the segment with 8m OAD, and 1.22 μm/0.26 μm for another one.

  5. Multilayer active shell mirrors for space telescopes

    NASA Astrophysics Data System (ADS)

    Steeves, John; Jackson, Kathryn; Pellegrino, Sergio; Redding, David; Wallace, J. Kent; Bradford, Samuel Case; Barbee, Troy

    2016-07-01

    A novel active mirror technology based on carbon fiber reinforced polymer (CFRP) substrates and replication techniques has been developed. Multiple additional layers are implemented into the design serving various functions. Nanolaminate metal films are used to provide a high quality reflective front surface. A backing layer of thin active material is implemented to provide the surface-parallel actuation scheme. Printed electronics are used to create a custom electrode pattern and flexible routing layer. Mirrors of this design are thin (< 1.0 mm), lightweight (2.7 kg/m2), and have large actuation capabilities. These capabilities, along with the associated manufacturing processes, represent a significant change in design compared to traditional optics. Such mirrors could be used as lightweight primaries for small CubeSat-based telescopes or as meter-class segments for future large aperture observatories. Multiple mirrors can be produced under identical conditions enabling a substantial reduction in manufacturing cost and complexity. An overview of the mirror design and manufacturing processes is presented. Predictions on the actuation performance have been made through finite element simulations demonstrating correctabilities on the order of 250-300× for astigmatic modes with only 41 independent actuators. A description of the custom metrology system used to characterize the active mirrors is also presented. The system is based on a Reverse Hartmann test and can accommodate extremely large deviations in mirror figure (> 100 μm PV) down to sub-micron precision. The system has been validated against several traditional techniques including photogrammetry and interferometry. The mirror performance has been characterized using this system, as well as closed-loop figure correction experiments on 150 mm dia. prototypes. The mirrors have demonstrated post-correction figure accuracies of 200 nm RMS (two dead actuators limiting performance).

  6. Lightweight active controlled primary mirror technology demonstrator

    NASA Astrophysics Data System (ADS)

    Mazzinghi, P.; Bratina, V.; Ferruzzi, D.; Gambicorti, L.; Simonetti, F.; Zuccaro Marchi, A.; Salinari, P.; Lisi, F.; Olivier, M.; Bursi, A.; Gallieni, D.; Biasi, R.; Pereira, J.

    2007-10-01

    This paper describes the design, manufacturing and test of a ground demonstrator of an innovative technology able to realize lightweight active controlled space-borne telescope mirror. This analysis is particularly devoted to applications for a large aperture space telescope for advanced LIDAR, but it can be used for any lightweight mirror. For a space-borne telescope the mirror weight is a fundamental parameter to be minimized (less than 15 Kg/m2), while maximizing the optical performances (optical quality better than λ/3). In order to guarantee these results, the best selected solution is a thin glass primary mirror coupled to a stiff CFRP (Carbon Fiber Reinforced Plastic) panel with a surface active control system. A preliminary design of this lightweight structure highlighted the critical areas that were deeply analyzed by the ground demonstrator: the 1 mm thick mirror survivability on launch and the actuator functional performances with low power consumption. To preserve the mirror glass the Electrostatic Locking technique was developed and is here described. The active optics technique, already widely used for ground based telescopes, consists of a metrology system (wave front sensor, WFS), a control algorithm and a system of actuators to slightly deform the primary mirror and/or displace the secondary, in a closed-loop control system that applies the computed corrections to the mirror's optical errors via actuators. These actuators types are properly designed and tested in order to guarantee satisfactory performances in terms of stroke, force and power consumption. The realized and tested ground demonstrator is a square CFRP structure with a flat mirror on the upper face and an active actuator beneath it. The test campaign demonstrated the technology feasibility and robustness, supporting the next step toward the large and flat surface with several actuators.

  7. Long-lived resonances at mirrors

    NASA Astrophysics Data System (ADS)

    Queisser, Friedemann; Unruh, William G.

    2016-12-01

    Motivated by realistic scattering processes of composite systems, we study the dynamics of a two-particle bound system which is scattered at a mirror. We consider two different scenarios: In the first case we assume that only one particle interacts directly with the mirror whereas in the second case both particles are scattered. The coherence between the transmitted and the reflected wave packet is reduced when the internal degree of freedom (the relative coordinate) of the bound system becomes excited. Depending on the particular system-mirror interaction, long-lived resonances can occur.

  8. Affect regulation: holding, containing and mirroring.

    PubMed

    Pedersen, Signe Holm; Poulsen, Stig; Lunn, Susanne

    2014-10-01

    Gergely and colleagues' state that their "Social Biofeedback Theory of Parental Affect Mirroring" can be seen as a kind of operationalization of the classical psychoanalytic concepts of holding, containing and mirroring. This article examines to what extent the social biofeedback theory of parental affect mirroring may be understood as a specification of these concepts. It is argued that despite similarities at a descriptive level the concepts are embedded in theories with different ideas of subjectivity. Hence an understanding of the concept of affect regulation as a concretization and specification of the classical concepts dilutes the complexity of both the concept of affect regulation and of the classical concepts.

  9. Fine alignment of a large segmented mirror

    NASA Technical Reports Server (NTRS)

    Dey, Thomas William (Inventor)

    2010-01-01

    A system for aligning a segmented mirror includes a source of radiation directed along a first axis to the segmented mirror and a beamsplitter removably inserted along the first axis for redirecting radiation from the first axis to a second axis, substantially perpendicular to the first axis. An imaging array is positioned along the second axis for imaging the redirected radiation, and a knife-edge configured for cutting the redirected radiation is serially positioned to occlude and not occlude the redirected radiation, effectively providing a variable radiation pattern detected by the imaging array for aligning the segmented mirror.

  10. Particle Deconfinement in a Bent Magnetic Mirror

    SciTech Connect

    Renaud Gueroult and Nathaniel J. Fisch

    2012-09-06

    Coils misalignment in a magnetic mirror can produce additional particle transport. The magnetic field non axi-symmetry is responsible for radial and longitudinal drifts in a way much similar to the neo-classical transport in a tandem mirror cell distorted by end plugs. Accordingly, a regime exhibiting large radial displacements - similar to the resonant regime in tandem mirrors - can be obtained by confining ions azimuthally, for example by means of a properly tuned radial electric field. Because of the mass dependence of the magnetic field non-homogeneity drift velocities, the azimuthal trapping is mass specific, allowing in principle the filtering of a specific species based on its mass.

  11. Theoretical aspects of the agile mirror

    NASA Astrophysics Data System (ADS)

    Manheimer, Wallace M.; Fernsler, Richard

    1994-01-01

    A planar plasma mirror which can be oriented electronically could have the capability of providing electronic steering of a microwave beam in a radar or electronic warfare system. This system is denoted the agile mirror. A recent experiment has demonstrated such a planar plasma and the associated microwave reflection. This plasma was produced by a hollow cathode glow discharge, where the hollow cathode was a grooved metallic trench in a Lucite plate. Various theoretical aspects of this configuration of an agile mirror are examined here.

  12. Tandem Mirror Reactor Systems Code (Version I)

    SciTech Connect

    Reid, R.L.; Finn, P.A.; Gohar, M.Y.; Barrett, R.J.; Gorker, G.E.; Spampinaton, P.T.; Bulmer, R.H.; Dorn, D.W.; Perkins, L.J.; Ghose, S.

    1985-09-01

    A computer code was developed to model a Tandem Mirror Reactor. Ths is the first Tandem Mirror Reactor model to couple, in detail, the highly linked physics, magnetics, and neutronic analysis into a single code. This report describes the code architecture, provides a summary description of the modules comprising the code, and includes an example execution of the Tandem Mirror Reactor Systems Code. Results from this code for two sensitivity studies are also included. These studies are: (1) to determine the impact of center cell plasma radius, length, and ion temperature on reactor cost and performance at constant fusion power; and (2) to determine the impact of reactor power level on cost.

  13. Stroboscopic Interferometer for Measuring Mirror Vibrations

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Robers, Ted

    2005-01-01

    Stroboscopic interferometry is a technique for measuring the modes of vibration of mirrors that are lightweight and, therefore, unavoidably flexible. The technique was conceived especially for modal characterization of lightweight focusing mirror segments to be deployed in outer space; however, the technique can be applied to lightweight mirrors designed for use on Earth as well as the modal investigation of other optical and mechanical structures. To determine the modal structure of vibration of a mirror, it is necessary to excite the mirror by applying a force that varies periodically with time at a controllable frequency. The excitation can utilize sinusoidal, square, triangular, or even asynchronous waveforms. Because vibrational modes occur at specific resonant frequencies, it is necessary to perform synchronous measurements and sweep the frequency to locate the significant resonant modes. For a given mode it is possible to step the phase of data acquisition in order to capture the modal behavior over a single cycle of the resonant frequency. In order to measure interferometrically the vibrational response of the mirror at a given frequency, an interferometer must be suitably aligned with the mirror and adjustably phase-locked with the excitation signal. As in conventional stroboscopic photography, the basic idea in stroboscopic interferometry is to capture an image of the shape of a moving object (in this case, the vibrating mirror) at a specified instant of time in the vibration cycle. Adjusting the phase difference over a full cycle causes the interference fringes to vary over the full range of motion for the mode at the excitation frequency. The interference-fringe pattern is recorded as a function of the phase difference, and, from the resulting data, the surface shape of the mirror for the given mode is extracted. In addition to the interferometer and the mirror to be tested, the equipment needed for stroboscopic interferometry includes an arbitrary

  14. Fiber ring laser with a feedback mirror.

    PubMed

    Abitan, H; Bohr, H; Pedersen, C F

    2005-12-20

    We describe the spectral and power features of a ytterbium-doped double-clad photonic crystal fiber laser that is operated in a ring configuration with an external mirror that feeds back only one of its two output beams. We compare the operation of the laser with and without an external feedback mirror. We find that the feedback mirror reduces significantly the spectral and power fluctuations. It is also responsible for an interesting spectral phenomenon: The laser frequency is drifting periodically over 9 nm at a rate of 2 nm/s from a short wavelength to a longer wavelength and vice versa.

  15. HCN laser with an adaptive output mirror

    SciTech Connect

    Kamenev, Yu E; Masalov, S A; Filimonova, A A

    2006-09-30

    A device for optimal coupling between a laser resonator and the external medium, having the form of one-dimensional wire grating conjugated with a plane mirror with an aperture, is proposed, developed and tested experimentally. The dependences of the output laser power on the separation between the grating and the mirror, diameter of the aperture in the plane mirror, and the grating period, are studied. The obtained results not only confirm the possibility of using such a coupling device, but also point towards the ways and principles of its application. (lasers)

  16. Exclusive lower extremity mirror movements and diastematomyelia.

    PubMed

    Tubbs, R Shane; Smyth, Matthew D; Dure, Leon S; Oakes, W Jerry

    2004-01-01

    Mirror movements usually seen in the Klippel-Feil syndrome are most commonly appreciated in the upper extremities. Lower extremity involvement is seen rarely and when observed, is found in conjunction with upper extremity mirror movements. We report what we believe to be the first case of mirror movements found exclusively in the lower extremities in a female patient presenting with tethered cord syndrome. Our hopes are that this report will help elucidate mechanisms involved with these anomalous movements, as currently there is no commonly accepted etiology.

  17. Perspex machine: VII. The universal perspex machine

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2006-01-01

    The perspex machine arose from the unification of projective geometry with the Turing machine. It uses a total arithmetic, called transreal arithmetic, that contains real arithmetic and allows division by zero. Transreal arithmetic is redefined here. The new arithmetic has both a positive and a negative infinity which lie at the extremes of the number line, and a number nullity that lies off the number line. We prove that nullity, 0/0, is a number. Hence a number may have one of four signs: negative, zero, positive, or nullity. It is, therefore, impossible to encode the sign of a number in one bit, as floating-point arithmetic attempts to do, resulting in the difficulty of having both positive and negative zeros and NaNs. Transrational arithmetic is consistent with Cantor arithmetic. In an extension to real arithmetic, the product of zero, an infinity, or nullity with its reciprocal is nullity, not unity. This avoids the usual contradictions that follow from allowing division by zero. Transreal arithmetic has a fixed algebraic structure and does not admit options as IEEE, floating-point arithmetic does. Most significantly, nullity has a simple semantics that is related to zero. Zero means "no value" and nullity means "no information." We argue that nullity is as useful to a manufactured computer as zero is to a human computer. The perspex machine is intended to offer one solution to the mind-body problem by showing how the computable aspects of mind and, perhaps, the whole of mind relates to the geometrical aspects of body and, perhaps, the whole of body. We review some of Turing's writings and show that he held the view that his machine has spatial properties. In particular, that it has the property of being a 7D lattice of compact spaces. Thus, we read Turing as believing that his machine relates computation to geometrical bodies. We simplify the perspex machine by substituting an augmented Euclidean geometry for projective geometry. This leads to a general

  18. The University of Tokyo Atacama Observatory 6.5m Telescope: design of mirror coating system and its performances

    NASA Astrophysics Data System (ADS)

    Takahashi, Hidenori; Yoshii, Yuzuru; Doi, Mamoru; Kohno, Kotaro; Miyata, Takashi; Motohara, Kentaro; Tanaka, Masuo; Minezaki, Takeo; Morokuma, Tomoki; Sako, Shigeyuki; Tamura, Yoichi; Tanabé, Toshihiko; Konishi, Masahiro; Kamizuka, Takafumi; Kato, Natsuko; Aoki, Tsutomu; Soyano, Takao; Tarusawa, Ken'ichi

    2016-07-01

    The telescope of the University of Tokyo Atacama Observatory has a primary mirror with a diameter in 6.5m. In order to fabricate the reflecting film initially on the mirror surface and to maintain its optical performance over a long period, we have a mirror-coating facility being installed at the summit of Co. Chajnantor (5,640m). The facility consists of a clean booth for stripping off the old film, a mirror coating chamber, and a cart with a lifter for handling the primary mirror. A conventional evaporation system with a metal pre-wetted filament array is adopted for achieving various optical requests. Among the many development items, the fabrication of the transportation and lifting cart has been already completed. It has efficient performance in load capacity (>60 tons) and maximum lifting height (1,750 mm). A cleaning machine having injection nozzles that can realize an efficient and safe cleaning sequence also been completed. A test of the evaporation system using dedicated filaments and filament boxes, which are customized to the TAO's requirements, has shown a uniform coating on a test mirror. An array pattern of the filaments has also been decided based on the coating tests to satisfy the optical specification of the telescope. A detailed design of the main chamber has been almost completed, it is only waiting for the production in the near future.

  19. Scaling laws for light weight optics, studies of light weight mirrors mounting and dynamic mirror stress, and light weight mirror and mount designs

    NASA Technical Reports Server (NTRS)

    Vukobratovich, Daniel; Richard, Ralph M.; Valente, Tina M.; Cho, Myung K.

    1990-01-01

    Scaling laws for light-weight optical systems are examined. A cubic relationship between mirror diameter and weight has been suggested and used by many designers of optical systems as the best description for all light-weight mirrors. A survey of existing light-weight systems in the open literature was made to clarify this issue. Fifty existing optical systems were surveyed with all varieties of light-weight mirrors including glass and beryllium structured mirrors, contoured mirrors, and very thin solid mirrors. These mirrors were then categorized and weight to diameter ratio was plotted to find a best curve for each case. A best fitting curve program tests nineteen different equations and ranks a goodness-to-fit for each of these equations. The resulting relationship found for each light-weight mirror category helps to quantify light-weight optical systems and methods of fabrication and provides comparisons between mirror types.

  20. Polishing X-ray Mirror Mandrel

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery, and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. MSFC's Space Optics Manufacturing Technology Center (SOMTC) has grinding and polishing equipment ranging from conventional spindles to custom-designed polishers. These capabilities allow us to grind precisely and polish a variety of optical devices, including x-ray mirror mandrels. This image shows Charlie Griffith polishing the half-meter mandrel at SOMTC.

  1. Mirror Advanced Reactor Study interim design report

    SciTech Connect

    Not Available

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  2. Coating considerations for mirrors of CPV devices

    SciTech Connect

    Schmauder, Torsten; Sauer, Peter; Ickes, Gerd

    2014-09-26

    One of the different optical concepts for concentrator devices is to place a focussing primary mirror behind a transparent front plate. In addition (also in case of Fresnel-diffractive main optics), further 'secondary' reflectors may be used further along the beam path. Such mirrors are usually implemented as coating stacks of a highly reflective metal - usually silver - and protective layers. The protective layers are preferably designed as reflection enhancing interference stack. The design of such protective layer stacks yields two difficulties, which are addressed in this paper: (a) vacuum coating of three-dimensional parts will result in a thickness distribution and the optical design of the stack should thus be tolerant to layer thickness variations, and (b) different places of the mirror will have different angle-of-incidence of the sunlight under operating conditions. As result, the layer stack has a different design at different places of the mirror.

  3. Applied physics: Optical trapping for space mirrors.

    PubMed

    McGloin, David

    2014-02-27

    Might it be possible to create mirrors for space telescopes, using nothing but microscopic particles held in place by light? A study that exploits a technique called optical binding provides a step towards this goal.

  4. The mirror mechanism: recent findings and perspectives.

    PubMed

    Rizzolatti, Giacomo; Fogassi, Leonardo

    2014-01-01

    Mirror neurons are a specific type of visuomotor neuron that discharge both when a monkey executes a motor act and when it observes a similar motor act performed by another individual. In this article, we review first the basic properties of these neurons. We then describe visual features recently investigated which indicate that, besides encoding the goal of motor acts, mirror neurons are modulated by location in space of the observed motor acts, by the perspective from which the others' motor acts are seen, and by the value associated with the object on which others' motor acts are performed. In the last part of this article, we discuss the role of the mirror mechanism in planning actions and in understanding the intention underlying the others' motor acts. We also review some human studies suggesting that motor intention in humans may rely, as in the monkey, on the mirror mechanism.

  5. Lightweight hollow rooftop mirrors for stabilized interferometry

    NASA Astrophysics Data System (ADS)

    Hill, Robert J.; Courtney, Trevor L.; Park, Samuel D.; Jonas, David M.

    2013-10-01

    Hollow rooftop mirrors, also known as dihedral retroreflectors, can simultaneously preserve polarization, minimize chromatic dispersion, and allow beams to be stacked inside an interferometer. Two hollow rooftop mirrors were fabricated and characterized using a Fizeau interferometer and an inexpensive home-built jig instead of a master cube. The mass was 3.3 g for a clear aperture surface area of 110 mm2 with maximum retroreflected beam deviation of 12 arc s. With a hollow rooftop mirror mounted on a piezoelectric transducer in one arm of a Mach-Zehnder interferometer, a displacement stability of ±0.8 nm rms was achieved using active feedback. The rooftop mirrors' suitability for Fourier transform spectroscopy was demonstrated.

  6. Auditory-vocal mirroring in songbirds.

    PubMed

    Mooney, Richard

    2014-01-01

    Mirror neurons are theorized to serve as a neural substrate for spoken language in humans, but the existence and functions of auditory-vocal mirror neurons in the human brain remain largely matters of speculation. Songbirds resemble humans in their capacity for vocal learning and depend on their learned songs to facilitate courtship and individual recognition. Recent neurophysiological studies have detected putative auditory-vocal mirror neurons in a sensorimotor region of the songbird's brain that plays an important role in expressive and receptive aspects of vocal communication. This review discusses the auditory and motor-related properties of these cells, considers their potential role on song learning and communication in relation to classical studies of birdsong, and points to the circuit and developmental mechanisms that may give rise to auditory-vocal mirroring in the songbird's brain.

  7. Coating considerations for mirrors of CPV devices

    NASA Astrophysics Data System (ADS)

    Schmauder, Torsten; Sauer, Peter; Ickes, Gerd

    2014-09-01

    One of the different optical concepts for concentrator devices is to place a focussing primary mirror behind a transparent front plate. In addition (also in case of Fresnel-diffractive main optics), further "secondary" reflectors may be used further along the beam path. Such mirrors are usually implemented as coating stacks of a highly reflective metal - usually silver - and protective layers. The protective layers are preferably designed as reflection enhancing interference stack. The design of such protective layer stacks yields two difficulties, which are addressed in this paper: (a) vacuum coating of three-dimensional parts will result in a thickness distribution and the optical design of the stack should thus be tolerant to layer thickness variations, and (b) different places of the mirror will have different angle-of-incidence of the sunlight under operating conditions. As result, the layer stack has a different design at different places of the mirror.

  8. Design Considerations for a Highly Segmented Mirror

    NASA Astrophysics Data System (ADS)

    Padin, Stephen

    2003-06-01

    Design issues for a 30-m highly segmented mirror are explored, with emphasis on parametric models of simple, inexpensive segments. A mirror with many small segments offers cost savings through quantity production and permits high-order active and adaptive wave-front corrections. For a 30-m f/1 .5 paraboloidal mirror made of spherical, hexagonal glass segments, with simple warping harnesses and three-point supports, the maximum segment diameter is ~100 mm, and the minimum segment thickness is ~5 mm. Large-amplitude, low-order gravitational deformations in the mirror cell can be compensated if the segments are mounted on a plate floating on astatic supports. Because gravitational deformations in the plate are small, the segment actuators require a stroke of only a few tens of micrometers, and the segment positions can be measured by a wave-front sensor.

  9. Electric dipole radiation near a mirror

    SciTech Connect

    Li Xin; Arnoldus, Henk F.

    2010-05-15

    The emission of radiation by a linearly oscillating electric dipole is drastically altered when the dipole is close to the surface of a mirror. The energy is not emitted along optical rays, as for a free dipole, but as a set of four optical vortices. The field lines of energy flow spiral around a set of two lines through the dipole. At a larger distance from the dipole, singularities and isolated vortices appear. It is shown that these interference vortices are due to the vanishing of the magnetic field at their centers. In the plane of the mirror there is a singular circle with a diameter which is proportional to the distance between the dipole and the mirror. Inside this circle, all energy flows to a singularity on the mirror surface.

  10. Space Optic Manufacturing - X-ray Mirror

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA's Space Optics Manufacturing Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century - including the long-term goal of imaging Earth-like planets in distant solar systems. To reduce the cost of mirror fabrication, Marshall Space Flight Center (MSFC) has developed replication techniques, the machinery and materials to replicate electro-formed nickel mirrors. The process allows fabricating precisely shaped mandrels to be used and reused as masters for replicating high-quality mirrors. This image shows a lightweight replicated x-ray mirror with gold coatings applied.

  11. Supersymmetric defect models and mirror symmetry

    SciTech Connect

    Hook, Anson; Kachru, Shamit; Torroba, Gonzalo

    2013-11-01

    We study supersymmetric field theories in three space-time dimensions doped by various configurations of electric charges or magnetic fluxes. These are supersymmetric avatars of impurity models. In the presence of additional sources such configurations are shown to preserve half of the supersymmetries. Mirror symmetry relates the two sets of configurations. We discuss the implications for impurity models in 3d NN = 4 QED with a single charged hypermultiplet (and its mirror, the theory of a free hypermultiplet) as well as 3d NN = 2 QED with one flavor and its dual, a supersymmetric Wilson-Fisher fixed point. Mirror symmetry allows us to find backreacted solutions for arbitrary arrays of defects in the IR limit of NN = 4 QED. Our analysis, complemented with appropriate string theory brane constructions, sheds light on various aspects of mirror symmetry, the map between particles and vortices and the emergence of ground state entropy in QED at finite density.

  12. ATST telescope mount: telescope of machine tool

    NASA Astrophysics Data System (ADS)

    Jeffers, Paul; Stolz, Günter; Bonomi, Giovanni; Dreyer, Oliver; Kärcher, Hans

    2012-09-01

    The Advanced Technology Solar Telescope (ATST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope mount has proportions similar to an 8 meter class telescope. The technology normally used in this class of telescope is well understood in the telescope community and has been successfully implemented in numerous projects. The world of large machine tools has developed in a separate realm with similar levels of performance requirement but different boundary conditions. In addition the competitive nature of private industry has encouraged development and usage of more cost effective solutions both in initial capital cost and thru-life operating cost. Telescope mounts move relatively slowly with requirements for high stability under external environmental influences such as wind buffeting. Large machine tools operate under high speed requirements coupled with high application of force through the machine but with little or no external environmental influences. The benefits of these parallel development paths and the ATST system requirements are being combined in the ATST Telescope Mount Assembly (TMA). The process of balancing the system requirements with new technologies is based on the experience of the ATST project team, Ingersoll Machine Tools who are the main contractor for the TMA and MT Mechatronics who are their design subcontractors. This paper highlights a number of these proven technologies from the commercially driven machine tool world that are being introduced to the TMA design. Also the challenges of integrating and ensuring that the differences in application requirements are accounted for in the design are discussed.

  13. Ultra-precision grinding of chemically vapor deposited silicon carbide mirrors for synchrotron radiation

    SciTech Connect

    Namba, Yoshiharu

    1996-12-31

    Chemically vapor deposited silicon carbide (CVD-SiC) is the most important material of mirrors for high-brightness synchrotron radiation beamlines, though the material is too difficult to be machined. It takes quite a long time to polish SiC substrate to make mirrors. This paper intends to reduce the machining time to make CVD-SiC mirrors by using ultra-precision grinding technology. The CVD-SiC sample has been ground into 0.4nm rms in surface roughness by a resinoid-bonded diamond wheel and an ultra-precision surface grinder having a glass-ceramic spindle of extremely-low thermal expansion. The surface roughness of ground samples were measured with TOPO-3D and AFM. 88.7% reflectivity has been obtained on the ground CVD-SiC flat surface, measured with X-ray of 0.834 nm in wavelength at the grazing incident angle of 0.7--0.95 degree. The reflectivity depends upon the angle between the direction of incident beam and grinding marks on the sample. The relationship between the surface roughness and grinding conditions was also discussed.

  14. Research on process technology of off-axis ellipsoid aspheric mirror

    NASA Astrophysics Data System (ADS)

    Liu, Dongmei; Ma, Ke; Jia, Zonghe

    2015-02-01

    In recent years, the off-axis aspheric surface is widely used in wide coverage and high-resolution space optical systems. In this paper, research on processing technology of high precision and high efficiency off-axis ellipsoid aspheric mirror was studied deeply. With the help of CNC milling and polishing machine, off-axis ellipsoid aspheric mirror with diameter of 58mm was developed, by optimizing the concentration of polish liquid, grinding size, machining direction and other process parameters, based on the disadvantage of traditional processing that off-axis aspheric is easy to generate edge splitting and secondary surface damage, a new processing method "vertical off-axis ellipsoid aspheric surface processing method" was put forward. This method not only ensures the accuracy of work piece of optical axis, surface accuracy and accuracy of the edge, but also reduces secondary surface damage, improves processing efficiency and achieves high precision and high efficiency processing of off-axis ellipsoid aspheric surface, which is conducive to mass production. Through the detection of off-axis ellipsoid aspheric mirror by Taylor Profiler , surface accuracy (PV value) is 0.1981μm, the aspheric surface finish is level II and the optical axis accuracy is 0.01mm that it meets the requirements.

  15. Motorized control for mirror mount apparatus

    SciTech Connect

    Cutburth, Ronald W.

    1989-01-01

    A motorized control and automatic braking system for adjusting mirror mount apparatus is disclosed. The motor control includes a planetary gear arrangement to provide improved pitch adjustment capability while permitting a small packaged design. The motor control for mirror mount adjustment is suitable for laser beam propagation applications. The brake is a system of constant contact, floating detents which engage the planetary gear at selected between-teeth increments to stop rotation instantaneously when the drive motor stops.

  16. Motorized control for mirror mount apparatus

    SciTech Connect

    Cutburth, R.W.

    1989-03-14

    This patent describes a motorized control and automatic braking system for adjusting mirror mount apparatus. The motor control includes a planetary gear arrangement to provide improved pitch adjustment capability while permitting a small packaged design. The motor control for mirror mount adjustment is suitable for laser beam propagation applications. The brake is a system of constant contact, floating detents which engage the planetary gear at selected between-teeth increments to stop rotation instantaneously when the drive motor stops.

  17. On horizonless temperature with an accelerating mirror

    NASA Astrophysics Data System (ADS)

    Good, Michael R. R.; Yelshibekov, Khalykbek; Ong, Yen Chin

    2017-03-01

    A new solution of a unitary moving mirror is found to produce finite energy and emit thermal radiation despite the absence of an acceleration horizon. In the limit that the mirror approaches the speed of light, the model corresponds to a black hole formed from the collapse of a null shell. For speeds less than light, the black hole correspondence, if it exists, is that of a remnant.

  18. Testing the first neutron mirror flipper

    NASA Astrophysics Data System (ADS)

    Pleshanov, N. K.; Syromyatnikov, V. G.

    2016-11-01

    The first neutron mirror flipper built as a magnetic Co70Fe30 (71.1 nm) layer on a non-magnetic periodic multilayer {NiMo(6.96 nm)/Ti(6.17 nm)}×20 was tested. Its efficiency at the Bragg peak was found to exceed 0.966. Thus, the possibility of producing neutron mirror spin turners, including π/2- and π-turners (flippers), was experimentally demonstrated.

  19. Differential interferometric measurement of mirror shape parameters

    NASA Astrophysics Data System (ADS)

    Robinson, Brian

    This project was inspired by the need for a remote method to accurately measure radius of curvature of mirrors tested under the NASA Advanced Mirror System Demonstrator program. Under this program, off axis parabolas (subscale candidates for James Webb Space Telescope optical elements) were tested under cryo-vac conditions. A remote, differential interferometric method is presented for measuring the shape parameters of general aspheric mirrors. The result of measurement is the assignment of best-fit values to a set of parameters that characterize the shape of the surface. If the mirror is nominally a conic of rotation, for example, the measurement yields the radius of curvature and conic constant. The method involves testing the optic in an interferometric center-of-curvature null configuration but can easily be extended to include conjugate null tests. During the measurement, known translational misalignments are introduced and the effects on the optical path length function are measured using a phase-shifting interferometer. Based on the nominal mirror shape, a model function is defined, up to a set of free shape parameters. The mirror shape parameters are regressed, based on the interferometric data, from this model. This differential measurement method works for on- and off-axis mirrors of all shapes and can be applied remotely as long as the mirror is mounted on an actuated stage. Hence, this measurement method would work well in a cryogenic testing situation. We have successfully applied the method to the case of an off-axis parabola with a nominal radius of curvature of 304.8 mm, a diameter of 76.17 mm, and a pupil offset of -89.40 mm.

  20. Experimental study of solar simulator mirror cryocontamination

    NASA Technical Reports Server (NTRS)

    Galjaev, V. L.; Makarov, A. A.; Afanassiev, N. A.

    1994-01-01

    The background and tasks formulation of the study of Solar Simulator collimation mirror cryocontamination in Large Thermal Vacuum Facility are outlined, research methods and experiment procedures are described, experimental relationships obtained are analyzed and practical recommendations are given. The accepted procedure of thermal vacuum tests as a rule defines the sequence of operations for verifying the spacecraft under test without taking into account measures for preventing Solar Simulator collimation mirror contamination and degradation. On the other hand, evacuation procedures is defined for conditions of achieving the required vacuum in the shortest possible time with using the available evacuation equipment at a regime close to the optimum one. Similarly, cryopanel cooling down cyclogram and test object preparation process are not analyzed from the viewpoint of ways of reducing environmental detrimental effects on thermal vacuum facility contamination-sensitive systems. Solar Simulator mirror contamination and its reflective characteristics change results in degradation of solar flux parameters and reduction of simulator continuous operation time. Methods of consideration of optical effects due to mirror surface contamination are actually missing. The effects themselves are not quite understood and data cited in literature as a rule, were obtained under conditions different from real thermal vacuum facility and therefore should be subjected to additional experimental verification. Only in the last few years contamination effect on optical surfaces degradation has been considered with using empirical relations. Mirror reflective properties degradation leads to the increase of Solar Simulator errors. This ultimately has an adverse effect on S/C ground development, schedule and cost of thermal vacuum tests. Besides, the mirror maintenance in operable state becomes more expensive. The present paper is dedicated to the study of Solar Simulator collimation

  1. Exit slit mirrors for the ebert spectrometer.

    PubMed

    Fastie, W G

    1972-09-01

    The use of a very long straight entrance slit in an Ebert grating spectrometer with two plane mirrors at the shorter exit slit to increase the energy density is described. This system has been employed in a far uv rocket spectrometer to provide higher sensitivity than has been achieved previously. The imaging properties and required slit and mirror adjustments are presented. Experimental results are included.

  2. High-speed mirror-scanning tracker

    NASA Astrophysics Data System (ADS)

    Tong, HengWei

    1999-06-01

    This paper introduces a high speed single-mirror scanner developed by us as a versatile tracker. It can be connected with a high speed camera, a TV tracker (or color video recorder) /measurer/recorder. It can be guided by a computer, a joystick (automatic or manual) or TV tracker. In this paper, we also present the advantages of our scanner contrasted with the limitations of fixed camera system. In addition, several usable projects of mirror scanner are discussed.

  3. Electroformed grazing incidence X-ray mirrors for a mirror array telescope

    NASA Technical Reports Server (NTRS)

    Ulmer, Melville P.; Matsui, Yutaka; Bedford, D. K.; Simnett, G. M.; Takacs, Peter Z.

    1987-01-01

    Grazing incidence Wolter type I mirrors for higher-energy X-rays have been replicated from two superpolished mandrels by electroforming. Single mirrors and a nested pair were tested with 1.5- and 6.4-keV X-rays, and their subminute of arc resolution and reflectivity close to the theoretical values are confirmed. The design of the mandrels, the mirror mounting scheme, and results of the X-ray test are presented. The microroughnesses of the mirrors measured using an optical profilometer were compared with the X-ray test results.

  4. Machine tool locator

    DOEpatents

    Hanlon, John A.; Gill, Timothy J.

    2001-01-01

    Machine tools can be accurately measured and positioned on manufacturing machines within very small tolerances by use of an autocollimator on a 3-axis mount on a manufacturing machine and positioned so as to focus on a reference tooling ball or a machine tool, a digital camera connected to the viewing end of the autocollimator, and a marker and measure generator for receiving digital images from the camera, then displaying or measuring distances between the projection reticle and the reference reticle on the monitoring screen, and relating the distances to the actual position of the autocollimator relative to the reference tooling ball. The images and measurements are used to set the position of the machine tool and to measure the size and shape of the machine tool tip, and examine cutting edge wear. patent

  5. Mirror reversal: empirical tests of competing accounts.

    PubMed

    Takano, Yohtaro; Tanaka, Akihiro

    2007-11-01

    In a mirror, left and right are said to look reversed. Surprisingly, this very familiar phenomenon, mirror reversal, has still no agreed-upon account to date. This study compared a variety of accounts in the light of empirical data. In Experiment 1, 102 students judged whether the mirror image of a person or a character looked reversed or not in 15 settings and also judged the directional relation between its components. In Experiment 2, 52 students made the reversal judgements in 13 settings. It was found for the first time that a substantial proportion of people denied the left-right mirror reversal of a person, whereas virtually all of them did recognize that of a character. This discrepancy strongly suggested that these two kinds of mirror reversal are produced by different processes, respectively. A number of findings including this discrepancy clearly contradicted two accounts that are currently active: the one based on the priority of the up-down and front-back axes over the left-right axis, and the one based on the physical rotation of an object. All the findings were consistent with an account that considered mirror reversal a complex of three different phenomena produced by three different processes, respectively.

  6. Aspheric mirror measurement based on fringe reflection

    NASA Astrophysics Data System (ADS)

    Su, Xianyu; Tang, Yan; Liu, Yuankun; Zhang, Qican; Xiang, Liqun

    2009-05-01

    The aspheric mirror can correct aberrations and improve imaging quality of optical system . M oreover using such mirror can reduce the num ber of optical elem ents in an optical system and further reduce the weight and size of the system . In order to improve the accuracy of aspheric mirror fabrication, there are many methods used to m easure aspheric mirror. Am ong these methods, the most popular one is interferom etry which can m easure the surface with very high accuracy. However, interferom etry commonly requires com plicated and expensive assistant optics, and its m easurem ent range is limited. In order to measure aspheric mirror conveniently and effectively, we further evolve the well know n approaches of 'Phase M easuring Deflectom ety'(PM D) to measure such surface. In this study, we present a novel m ethod based on fringe reflection to m easure aspheric m irror. In the m easurem ent process, the screen and the cam era are m oved along the mirror optical axis, respectively. Using the phase information of the recording fringe patterns, for each cam era pixel, we can calculate the slope and coordinate of its corresponding point on the surface to be tested. By integrating, the absolute height of the tested surface can be reconstructed. Com pared with traditional PM D, this m ethod can m easure the absolute height of an aspheric m irror unam biguously and doesn't need com plex calibration.

  7. The Dizzying Depths of the Cylindrical Mirror

    NASA Astrophysics Data System (ADS)

    DeWeerd, Alan J.; Hill, S. Eric

    2005-02-01

    A typical introduction to geometrical optics treats plane and spherical mirrors. At first glance, it may be surprising that texts seldom mention the cylindrical mirror, except for the occasional reference to use in fun houses and to viewing anamorphic art.1,2 However, even a cursory treatment reveals its complexity. Holzberlein used an extended object to qualitatively illustrate that images are produced both before and behind a concave cylindrical mirror.3 He also speculated on how this extreme astigmatism results in an observer's dizziness. By considering a simple point object, we make a more detailed analysis of the cylindrical mirror and the dizziness it induces. First, we illustrate how rays from a point object reflect to form not one point image but two line images. Next, we describe how an observer perceives a likeness of the object. Finally, we suggest how confusing depth cues induce dizziness. Although we focus on the concave cylindrical mirror, the discussion is easy to generalize to the convex cylindrical mirror.

  8. Development of CFRP mirrors for space telescopes

    NASA Astrophysics Data System (ADS)

    Utsunomiya, Shin; Kamiya, Tomohiro; Shimizu, Ryuzo

    2013-09-01

    CFRP (Caron fiber reinforced plastics) have superior properties of high specific elasticity and low thermal expansion for satellite telescope structures. However, difficulties to achieve required surface accuracy and to ensure stability in orbit have discouraged CFRP application as main mirrors. We have developed ultra-light weight and high precision CFRP mirrors of sandwich structures composed of CFRP skins and CFRP cores using a replica technique. Shape accuracy of the demonstrated mirrors of 150 mm in diameter was 0.8 μm RMS (Root Mean Square) and surface roughness was 5 nm RMS as fabricated. Further optimization of fabrication process conditions to improve surface accuracy was studied using flat sandwich panels. Then surface accuracy of the flat CFRP sandwich panels of 150 mm square was improved to flatness of 0.2 μm RMS with surface roughness of 6 nm RMS. The surface accuracy vs. size of trial models indicated high possibility of fabrication of over 1m size mirrors with surface accuracy of 1μm. Feasibility of CFRP mirrors for low temperature applications was examined for JASMINE project as an example. Stability of surface accuracy of CFRP mirrors against temperature and moisture was discussed.

  9. Evaluation of microfabricated deformable mirror systems

    NASA Astrophysics Data System (ADS)

    Cowan, William D.; Lee, Max K.; Bright, Victor M.; Welsh, Byron M.

    1998-09-01

    This paper presents recent result for aberration correction and beam steering experiments using polysilicon surface micromachined piston micromirror arrays. Microfabricated deformable mirrors offer a substantial cost reduction for adaptive optic systems. In addition to the reduced mirror cost, microfabricated mirrors typically require low control voltages, thus eliminating high voltage amplifiers. The greatly reduced cost per channel of adaptive optic systems employing microfabricated deformable mirrors promise high order aberration correction at low cost. Arrays of piston micromirrors with 128 active elements were tested. Mirror elements are on a 203 micrometers 12 by 12 square grid. The overall array size is 2.4 mm square. The arrays were fabricated in the commercially available DARPA supported MUMPs surface micromachining foundry process. The cost per mirror array in this prototyping process is less than 200 dollars. Experimental results are presented for a hybrid correcting element comprised of a lenslet array and piston micromirror array, and for a piston micromirror array only. Also presented is a novel digital deflection micromirror which requires no digital to analog converters, further reducing the cost of adaptive optics system.

  10. Vibration damping for the Segmented Mirror Telescope

    NASA Astrophysics Data System (ADS)

    Maly, Joseph R.; Yingling, Adam J.; Griffin, Steven F.; Agrawal, Brij N.; Cobb, Richard G.; Chambers, Trevor S.

    2012-09-01

    The Segmented Mirror Telescope (SMT) at the Naval Postgraduate School (NPS) in Monterey is a next-generation deployable telescope, featuring a 3-meter 6-segment primary mirror and advanced wavefront sensing and correction capabilities. In its stowed configuration, the SMT primary mirror segments collapse into a small volume; once on location, these segments open to the full 3-meter diameter. The segments must be very accurately aligned after deployment and the segment surfaces are actively controlled using numerous small, embedded actuators. The SMT employs a passive damping system to complement the actuators and mitigate the effects of low-frequency (<40 Hz) vibration modes of the primary mirror segments. Each of the six segments has three or more modes in this bandwidth, and resonant vibration excited by acoustics or small disturbances on the structure can result in phase mismatches between adjacent segments thereby degrading image quality. The damping system consists of two tuned mass dampers (TMDs) for each of the mirror segments. An adjustable TMD with passive magnetic damping was selected to minimize sensitivity to changes in temperature; both frequency and damping characteristics can be tuned for optimal vibration mitigation. Modal testing was performed with a laser vibrometry system to characterize the SMT segments with and without the TMDs. Objectives of this test were to determine operating deflection shapes of the mirror and to quantify segment edge displacements; relative alignment of λ/4 or better was desired. The TMDs attenuated the vibration amplitudes by 80% and reduced adjacent segment phase mismatches to acceptable levels.

  11. Development of Nanolaminate Thin Shell Mirrors

    SciTech Connect

    Hickey, G S; Lih, S S; Barbee, T

    2002-08-09

    The space science community has identified a need for ultra-light weight, large aperture optical systems that are capable of producing high-resolution images of low contrast. Current mirror technologies are limited due either to not being scalable to larger sizes at reasonable masses, or to lack of surface finish, dimensional stability in a space environment or long fabrication times. This paper will discuss the development of thin-shell, nano-laminate mirror substrates that are capable of being electro-actively figured. This technology has the potential to substantially reduce the cost of space based optics by allowing replication of ultra-lightweight primary mirrors from a master precision tool. Precision master tools have been shown to be used multiple times with repeatable surface quality results with less than one week fabrication times for the primary optical mirror substrate. Current development has developed a series of 0.25 and 0.5 meter spherical nanolaminate mirrors that are less than 0.5 kg/m{sup 2} areal density before electroactive components are mounted, and a target of less than 2.0 kg/m with control elements. This paper will provide an overview of nanolaminate materials for optical mirrors, modeling of their behavior under figure control and experiments conducted to validate precision control.

  12. Cryogenic Test Results of Hextek Mirror

    NASA Technical Reports Server (NTRS)

    Hadaway, James; Stahl, H. Philip; Eng, Ron; Hogue, William

    2004-01-01

    A 250 mm diameter lightweight borosilicate mirror has been interferometrically tested from room-temperature down to 30 K at the X-Ray Calibration Facility (XRCF) at Marshall Space Flight Center (MSFC). The minor blank was manufactured by Hextek Corporation using a high-temperature gas fusion process and was then polished at MSFC. It is a sandwich-type mirror consisting of a thin face-sheet (approx.1.5 mm thick), a core structure (20 mm thick, approx.43 mm diameter cells, & 0.5-1.2 mm thick walls), and a thin back-sheet (3 mm thick). The mirror has a 2500 mm spherical radius-of- curvature @/lo). The areal density is 14 kg/sq m. The mirror was tested in the 1 m x 2 m chamber using an Instantaneous Phase Interferometer (PI) from ADE Phase Shift Technologies. The mirror was tested twice. The first test measured the change in surface figure from ambient to 30 K and the repeatability of the change. An attempt was then made by QED Technologies to cryo-figure the mirror using magnetorheological finishing. The second test measured the effectiveness of the cryo- figuring. This paper will describe the test goals, the test instrumentation, and the test results for these cryogenic tests.

  13. Agent Based Computing Machine

    DTIC Science & Technology

    2005-12-09

    coordinates as in cellular automata systems. But using biology as a model suggests that the most general systems must provide for partial, but constrained...17. SECURITY CLASSIFICATION OF 118. SECURITY CLASSIFICATION OF 19. SECURITY CLASSIFICATION OF 20. LIMITATION OF ABSTRA REPORT THIS PAGE ABSTRACT...system called an "agent based computing" machine (ABC Machine). The ABC Machine is motivated by cellular biochemistry and it is based upon a concept

  14. Perspex machine II: visualization

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2004-12-01

    We review the perspex machine and improve it by reducing its halting conditions to one condition. We also introduce a data structure, called the "access column," that can accelerate a wide class of perspex programs. We show how the perspex can be visualised as a tetrahedron, artificial neuron, computer program, and as a geometrical transformation. We discuss the temporal properties of the perspex machine, dissolve the famous time travel paradox, and present a hypothetical time machine. Finally, we discuss some mental properties and show how the perspex machine solves the mind-body problem and, specifically, how it provides one physical explanation for the occurrence of paradigm shifts.

  15. Perspex machine II: visualization

    NASA Astrophysics Data System (ADS)

    Anderson, James A. D. W.

    2005-01-01

    We review the perspex machine and improve it by reducing its halting conditions to one condition. We also introduce a data structure, called the "access column," that can accelerate a wide class of perspex programs. We show how the perspex can be visualised as a tetrahedron, artificial neuron, computer program, and as a geometrical transformation. We discuss the temporal properties of the perspex machine, dissolve the famous time travel paradox, and present a hypothetical time machine. Finally, we discuss some mental properties and show how the perspex machine solves the mind-body problem and, specifically, how it provides one physical explanation for the occurrence of paradigm shifts.

  16. Progress in machine consciousness.

    PubMed

    Gamez, David

    2008-09-01

    This paper is a review of the work that has been carried out on machine consciousness. A clear overview of this diverse field is achieved by breaking machine consciousness down into four different areas, which are used to understand its aims, discuss its relationship with other subjects and outline the work that has been carried out so far. The criticisms that have been made against machine consciousness are also covered, along with its potential benefits, and the work that has been done on analysing systems for signs of consciousness. Some of the social and ethical issues raised by machine consciousness are examined at the end of the paper.

  17. Chaotic Boltzmann machines

    NASA Astrophysics Data System (ADS)

    Suzuki, Hideyuki; Imura, Jun-Ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-04-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented.

  18. Chaotic Boltzmann machines.

    PubMed

    Suzuki, Hideyuki; Imura, Jun-ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-01-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented.

  19. Manufacture of large-scale lightweight SiC mirror for space

    NASA Astrophysics Data System (ADS)

    Huang, Zhengren; Liu, Guiling; Liu, Xuejian; Chen, Zhongming; Jiang, Dongliang

    2012-01-01

    Large-scale lightweight silicon carbide (SiC) mirrors were manufactured for space. Sintered SiC (SSiC) ceramic was adopted as the material to manufacture these mirrors. Complex structure designed for highly weight reduction and installation requirements was near-net-shape formed on SiC green body by digital machining technique before the high temperature sintering process. The dimensional accuracy of thin ribs and faceplate can be precisely controlled above 99.5%. During sintering process, the temperature distribution was kept uniform enough to avoid residual stress and deformation in the whole furnace. Isotropic shrinkage occurs during densification from SiC green body to ceramic with a fluctuation less than 0.3%, which is the dimension error of the final size as well. Mirror surface with low surface roughness, high shape accuracy and reflectivity was finished by polishing and plating. Moreover, large-scale lightweight SSiC mirror was demonstrated to be suitable for space use by tests simulating launch conditions and space environments.

  20. Development of plasma sources for ICRF heating experiment in KMAX mirror device

    NASA Astrophysics Data System (ADS)

    Sun, Xuan; Liu, Ming; Yi, Hongshen; Lin, Munan; Shi, Peiyun

    2016-10-01

    KMAX, Keda Mirror with AXisymmeticity, is a tandem mirror machine with a length of 10 meters and diameters of 1.2 meters in the central cell and 0.3 meters in the mirror throat. In the past experiments, the plasma was generated by helicon wave launched from the west end. We obtained the blue core mode in argon discharge, however, it cannot provide sufficient plasma for hydrogen discharge, which is at least 1012 cm-3 required for effective ICRF heating. Several attempts have thus been tried or under design to increase the central cell's plasma density: (1) a washer gun with aperture of 1cm has been successfully tested, and a plasma density of 1013 cm-3 was achieved in the west cell near the gun, however, the plasma is only 1011 cm-3 in the central cell possible due to the mirror trapping and/or neutral quenching effect (2) a larger washer gun with aperture of 2.5 cm and a higher power capacitor bank are being assembled in order to generate more plasmas. In addition, how to mitigate the neutrals is under consideration (3) A hot cathode is been designed and will be tested in combination with plasma gun or alone. Preliminary results from those plasma sources will be presented and discussed.

  1. Development of surface profiler for master mandrel of x-ray ellipsoidal mirror

    NASA Astrophysics Data System (ADS)

    Takei, Yoshinori; Mimura, Hidekazu

    2016-09-01

    The performance of ellipsoidal mirrors, which can be used to focus soft X-rays to nanometer spots, has not yet been optimized. Development of the surface profiler used in the fabrication process is a key step toward improving the performance of such mirrors. Because ellipsoidal mirrors have a complex geometry, our group has developed the following two-step process for their fabrication. First, a master mandrel with the inverse shape is prepared, after which the ellipsoidal mirror is fabricated by replicating the surface using an electroforming method. In this study, we develop a surface profiler for the master mandrel using multiple displacement sensors and motorized stages. One displacement sensor is used to measure the surface profile and the others are used to measure the motion errors of the stages. The longitudinal surface profiles of the mandrel could be measured with a repeatability of 1.58 nm (RMS). Based on the measured shape error profile, shape correction processing was conducted using elastic emission machining (EEM), which is an ultra-precision technique. After performing EEM three times, the shape error of the mandrel improved from 20.5 nm (RMS) to 4.2 nm (RMS).

  2. The mirror illusion: does proprioceptive drift go hand in hand with sense of agency?

    PubMed

    Tajima, Daisuke; Mizuno, Tota; Kume, Yuichiro; Yoshida, Takako

    2015-01-01

    Vection can be regarded as the illusion of "whole-body" position perception. In contrast, the mirror illusion is that of "body-part" position perception. When participants viewed their left hands in a mirror positioned along the midsaggital axis while moving both hands synchronously, they hardly noticed the spatial offset between the hand in the mirror and the obscured real right hand. This illusion encompasses two phenomena: proprioceptive drift and sense of agency. Proprioceptive drift represented a perceptual change in the position of the obscured hand relative to that of the hand in the mirror. Sense of agency referred to the participants' subjective sense of controlling body image as they would their own bodies. We examined the spatial offset between these two phenomena. Participants responded to a two-alternative forced choice (2AFC) question regarding the subjective position of their right hands and questionnaires regarding sense of agency at various positions of the right hand. We analyzed the 2AFC data using a support vector machine and compared its classification result and the questionnaire results. Our data analysis suggested that the two phenomena were observed in concentric space, but the estimated range of the proprioceptive drift was slightly narrower than the range of agency. Although this outcome can be attributed to differences in measurement or analysis, to our knowledge, this is the first report to suggest that proprioceptive drift and sense of agency are concentric and almost overlap.

  3. Laser Alignment Techniques For Simultaneous Machine Tool Geometric Error Detection

    NASA Astrophysics Data System (ADS)

    Ni, J.; Wu, S. M.

    1989-01-01

    An optical measurement system has been developed for the simultaneous detection of multiple geometric error components of machine tools. The system is designed based upon laser alignment techniques where laser beams are used as measurement reference datum. The system can measure simultaneously 5 error components for each moving axis of a machine tool or coordinate measuring machine. They are: two straightness error components, pitch, yaw, and roll errors. Through actual calibration and measurement, the accuracy of the current system is estimated to be 2 µm for straightness measurements and better than 0.05 arcsec for angular error measurements with a 0.5 m offset between a reflecting mirror and a receiving photo sensor.

  4. Drum cutter mining machine

    SciTech Connect

    Oberste-beulmann, K.; Schupphaus, H.

    1980-02-19

    A drum cutter mining machine includes a machine frame with a winch having a drive wheel to engage a rack or chain which extends along the path of travel by the mining machine to propel the machine along a mine face. The mining machine is made up of discrete units which include a machine body and machine housings joined to opposite sides of the machine body. The winch is either coupled through a drive train with a feed drive motor or coupled to the drive motor for cutter drums. The machine housings each support a pivot shaft coupled by an arm to a drum cutter. One of these housings includes a removable end cover and a recess adapted to receive a support housing for a spur gear system used to transmit torque from a feed drive motor to a reduction gear system which is, in turn, coupled to the drive wheel of the winch. In one embodiment, a removable end cover on the machine housing provides access to the feed drive motor. The feed drive motor is arranged so that the rotational axis of its drive output shaft extends transversely to the stow side of the machine frame. In another embodiment, the reduction gear system is arranged at one side of the pivot shaft for the cutter drum while the drive motor therefor is arranged at the other side of the pivot shaft and coupled thereto through the spur gear system. In a further embodiment, the reduction gear system is disposed between the feed motor and the pivot shaft.

  5. Magnetic mirror fusion-fission early history and applicability to other systems

    SciTech Connect

    Moir, R

    2009-08-24

    In the mid 1970s to mid 1980s the mirror program was stuck with a concept, the Standard Mirror that was Q {approx} 1 where Q=P{sub fusion}/P{sub injection}. Heroic efforts were put into hybridizing thinking added energy and fuel sales would make a commercial product. At the same time the tokamak was thought to allow ignition and ultrahigh Q values of 20 or even higher. There was an effort to use neutral beams to drive the tokamak just like the mirror machines were driven in which case the Q value plunged to a few, however this was thought to be achievable decades earlier than the high Q versions. Meanwhile current drive and other features of the tokamak have seen the projected Q values come down to the range of 10. Meanwhile the mirror program got Q enhancement into high gear and various tandem mirrors projected Q values up towards 10 and with advanced features over 10 with axi-symmetric magnets (See R. F. Post papers), however the experimental program is all but non-existent. Meanwhile, the gas dynamic trap mirror system which is present day state-of-the-art can with low risk produce Q of {approx}0.1 useful for a low risk, low cost neutron source for materials development useful for the development of materials for all fusion concepts (see Simonen white paper: 'A Physics-Based Strategy to Develop a Mirror Fusion-Fission Hybrid' and D.D. Ryutov, 'Axisymmetric MHD-stable mirror as a neutron source and a driver for a fusion-fission hybrid'). Many early hybrid designs with multi-disciplinary teams were carried out in great detail for the mirror system with its axi-symmetric blanket modules. It is recognized that most of these designs are adaptable to tokamak or inertial fusion geometry. When Q is low (1 to 2) economics gives a large economic penalty for high recirculating power. These early studies covered the three design types: Power production, fuel production and waste burning. All three had their place but power production fell away because every study showed

  6. Diamond machine tool face lapping machine

    DOEpatents

    Yetter, H.H.

    1985-05-06

    An apparatus for shaping, sharpening and polishing diamond-tipped single-point machine tools. The isolation of a rotating grinding wheel from its driving apparatus using an air bearing and causing the tool to be shaped, polished or sharpened to be moved across the surface of the grinding wheel so that it does not remain at one radius for more than a single rotation of the grinding wheel has been found to readily result in machine tools of a quality which can only be obtained by the most tedious and costly processing procedures, and previously unattainable by simple lapping techniques.

  7. Design and construction of a cost-efficient Arduino-based mirror galvanometer system for scanning optical microscopy

    NASA Astrophysics Data System (ADS)

    Hsu, Jen-Feng; Dhingra, Shonali; D'Urso, Brian

    2017-01-01

    Mirror galvanometer systems (galvos) are commonly employed in research and commercial applications in areas involving laser imaging, laser machining, laser-light shows, and others. Here, we present a robust, moderate-speed, and cost-efficient home-built galvo system. The mechanical part of this design consists of one mirror, which is tilted around two axes with multiple surface transducers. We demonstrate the ability of this galvo by scanning the mirror using a computer, via a custom driver circuit. The performance of the galvo, including scan range, noise, linearity, and scan speed, is characterized. As an application, we show that this galvo system can be used in a confocal scanning microscopy system.

  8. Optical Performance Modeling of FUSE Telescope Mirror

    NASA Technical Reports Server (NTRS)

    Saha, Timo T.; Ohl, Raymond G.; Friedman, Scott D.; Moos, H. Warren

    2000-01-01

    We describe the Metrology Data Processor (METDAT), the Optical Surface Analysis Code (OSAC), and their application to the image evaluation of the Far Ultraviolet Spectroscopic Explorer (FUSE) mirrors. The FUSE instrument - designed and developed by the Johns Hopkins University and launched in June 1999 is an astrophysics satellite which provides high resolution spectra (lambda/Delta(lambda) = 20,000 - 25,000) in the wavelength region from 90.5 to 118.7 nm The FUSE instrument is comprised of four co-aligned, normal incidence, off-axis parabolic mirrors, four Rowland circle spectrograph channels with holographic gratings, and delay line microchannel plate detectors. The OSAC code provides a comprehensive analysis of optical system performance, including the effects of optical surface misalignments, low spatial frequency deformations described by discrete polynomial terms, mid- and high-spatial frequency deformations (surface roughness), and diffraction due to the finite size of the aperture. Both normal incidence (traditionally infrared, visible, and near ultraviolet mirror systems) and grazing incidence (x-ray mirror systems) systems can be analyzed. The code also properly accounts for reflectance losses on the mirror surfaces. Low frequency surface errors are described in OSAC by using Zernike polynomials for normal incidence mirrors and Legendre-Fourier polynomials for grazing incidence mirrors. The scatter analysis of the mirror is based on scalar scatter theory. The program accepts simple autocovariance (ACV) function models or power spectral density (PSD) models derived from mirror surface metrology data as input to the scatter calculation. The end product of the program is a user-defined pixel array containing the system Point Spread Function (PSF). The METDAT routine is used in conjunction with the OSAC program. This code reads in laboratory metrology data in a normalized format. The code then fits the data using Zernike polynomials for normal incidence

  9. Dual-use bimorph deformable mirrors

    NASA Astrophysics Data System (ADS)

    Griffith, M. S.; Laycock, L. C.; Bagshaw, J. M.; Rowe, D.

    2005-11-01

    Adaptive Optics (AO) is a critical underpinning technology for future optical countermeasures, laser delivery, target illumination and imaging systems. It measures and compensates for optical distortion caused by transmission through the atmosphere, resulting in the ability to deploy smaller lasers and identify targets at greater ranges. AO is also well established in ground based astronomy, and is finding applications in free space optical communications and ophthalmology. One of the key components in an AO system is the wavefront modifier, which acts on the incoming or outgoing beam to counter the effects of the atmosphere. BAE SYSTEMS ATC is developing multi-element Deformable Bimorph Mirrors (DBMs) for such applications. A traditional bimorph deformable mirror uses a set of edge electrodes outside the active area in order to meet the required boundary conditions for the active aperture. This inflicts a significant penalty in terms of bandwidth, which is inversely proportional to the square of the full mirror diameter. We have devised a number of novel mounting arrangements that reduce dead space and thus provide a much improved trade-off between bandwidth and stroke. These schemes include a novel method for providing vertical displacement at the periphery of the aperture, a method for providing a continuous compliant support underneath the bimorph mirror, and a method for providing a three point support underneath the bimorph. In all three cases, there is no requirement for edge electrodes to provide the boundary conditions, resulting in devices of much higher bandwidth. The target is to broaden the use of these types of mirror beyond the current limits of either low order/low bandwidth, to address the high order, high bandwidth systems required by long range, horizontal path applications. This paper will discuss the different mirror designs, and present experimental results for the most recently assembled mirrors.

  10. 14. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific Railroad Carlin Shops, view to north (90mm lens). - Southern Pacific Railroad, Carlin Shops, Roundhouse Machine Shop Extension, Foot of Sixth Street, Carlin, Elko County, NV

  11. BRITISH MOLDING MACHINE, PBQ AUTOMATIC COPE AND DRAG MOLDING MACHINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BRITISH MOLDING MACHINE, PBQ AUTOMATIC COPE AND DRAG MOLDING MACHINE MAKES BOTH MOLD HALVES INDIVIDUALLY WHICH ARE LATER ROTATED, ASSEMBLED, AND LOWERED TO POURING CONVEYORS BY ASSISTING MACHINES. - Southern Ductile Casting Company, Casting, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  12. Integration of Mirror Design with Suspension System using NASA's New Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold,William R., Sr.; Bevan, Ryan M.; Stahl, Philip

    2013-01-01

    Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.

  13. Integration of Mirror Design with Suspension System Using NASA's New Mirror Modeling Software

    NASA Technical Reports Server (NTRS)

    Arnold, William R., Sr.; Bevan, Ryan M.; Stahl, H. Philip

    2013-01-01

    Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.

  14. THE TEACHING MACHINE.

    ERIC Educational Resources Information Center

    KLEIN, CHARLES; WAYNE, ELLIS

    THE ROLE OF THE TEACHING MACHINE IS COMPARED WITH THE ROLE OF THE PROGRAMED TEXTBOOK. THE TEACHING MACHINE IS USED FOR INDIVIDUAL INSTRUCTION, CONTAINS AND PRESENTS PROGRAM CONTENT IN STEPS, PROVIDES A MEANS WHEREBY THE STUDENT MAY RESPOND TO THE PROGRAM, PROVIDES THE STUDENT WITH IMMEDIATE INFORMATION OF SOME KIND CONCERNING HIS RESPONSE THAT CAN…

  15. Semantics via Machine Translation

    ERIC Educational Resources Information Center

    Culhane, P. T.

    1977-01-01

    Recent experiments in machine translation have given the semantic elements of collocation in Russian more objective criteria. Soviet linguists in search of semantic relationships have attempted to devise a semantic synthesis for construction of a basic language for machine translation. One such effort is summarized. (CHK)

  16. The Hooey Machine.

    ERIC Educational Resources Information Center

    Scarnati, James T.; Tice, Craig J.

    1992-01-01

    Describes how students can make and use Hooey Machines to learn how mechanical energy can be transferred from one object to another within a system. The Hooey Machine is made using a pencil, eight thumbtacks, one pushpin, tape, scissors, graph paper, and a plastic lid. (PR)

  17. Machining heavy plastic sections

    NASA Technical Reports Server (NTRS)

    Stalkup, O. M.

    1967-01-01

    Machining technique produces consistently satisfactory plane-parallel optical surfaces for pressure windows, made of plexiglass, required to support a photographic study of liquid rocket combustion processes. The surfaces are machined and polished to the required tolerances and show no degradation from stress relaxation over periods as long as 6 months.

  18. Technique for Machining Glass

    NASA Technical Reports Server (NTRS)

    Rice, S. H.

    1982-01-01

    Process for machining glass with conventional carbide tools requires a small quantity of a lubricant for aluminum applied to area of glass to be machined. A carbide tool is then placed against workpiece with light pressure. Tool is raised periodically to clear work of glass dust and particles. Additional lubricant is applied as it is displaced.

  19. Compound taper milling machine

    NASA Technical Reports Server (NTRS)

    Campbell, N. R.

    1969-01-01

    Simple, inexpensive milling machine tapers panels from a common apex to a uniform height at panel edge regardless of the panel perimeter configuration. The machine consists of an adjustable angled beam upon which the milling tool moves back and forth above a rotatable table upon which the workpiece is held.

  20. Stirling machine operating experience

    SciTech Connect

    Ross, B.; Dudenhoefer, J.E.

    1994-09-01

    Numerous Stirling machines have been built and operated, but the operating experience of these machines is not well known. It is important to examine this operating experience in detail, because it largely substantiates the claim that stirling machines are capable of reliable and lengthy operating lives. The amount of data that exists is impressive, considering that many of the machines that have been built are developmental machines intended to show proof of concept, and are not expected to operate for lengthy periods of time. Some Stirling machines (typically free-piston machines) achieve long life through non-contact bearings, while other Stirling machines (typically kinematic) have achieved long operating lives through regular seal and bearing replacements. In addition to engine and system testing, life testing of critical components is also considered. The record in this paper is not complete, due to the reluctance of some organizations to release operational data and because several organizations were not contacted. The authors intend to repeat this assessment in three years, hoping for even greater participation.

  1. Machine Translation Project

    NASA Technical Reports Server (NTRS)

    Bajis, Katie

    1993-01-01

    The characteristics and capabilities of existing machine translation systems were examined and procurement recommendations were developed. Four systems, SYSTRAN, GLOBALINK, PC TRANSLATOR, and STYLUS, were determined to meet the NASA requirements for a machine translation system. Initially, four language pairs were selected for implementation. These are Russian-English, French-English, German-English, and Japanese-English.

  2. Simple Machines Made Simple.

    ERIC Educational Resources Information Center

    St. Andre, Ralph E.

    Simple machines have become a lost point of study in elementary schools as teachers continue to have more material to cover. This manual provides hands-on, cooperative learning activities for grades three through eight concerning the six simple machines: wheel and axle, inclined plane, screw, pulley, wedge, and lever. Most activities can be…

  3. Simple Machine Junk Cars

    ERIC Educational Resources Information Center

    Herald, Christine

    2010-01-01

    During the month of May, the author's eighth-grade physical science students study the six simple machines through hands-on activities, reading assignments, videos, and notes. At the end of the month, they can easily identify the six types of simple machine: inclined plane, wheel and axle, pulley, screw, wedge, and lever. To conclude this unit,…

  4. Introduction to machine learning.

    PubMed

    Baştanlar, Yalin; Ozuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning approaches for this application area. In this chapter, we first review the fundamental concepts of machine learning such as feature assessment, unsupervised versus supervised learning and types of classification. Then, we point out the main issues of designing machine learning experiments and their performance evaluation. Finally, we introduce some supervised learning methods.

  5. Flute instability and the associated radial transport in the tandem mirror with a divertor mirror cell

    SciTech Connect

    Katanuma, I.; Yagi, K.; Haraguchi, Y.; Ichioka, N.; Masaki, S.; Ichimura, M.; Imai, T.

    2010-11-15

    The flute instability and the associated radial transport are investigated in the tandem mirror with a divertor mirror cell (the GAMMA10 A-divertor) with help of computer simulation, where GAMMA10 is introduced [Inutake et al., Phys. Rev. Lett. 55, 939 (1985)]. The basic equations used in the simulation were derived on the assumption of an axisymmetric magnetic field. So the high plasma pressure in a nonaxisymmetric minimum-B anchor mirror cell, which is important for the flute mode stability, is taken into account by redefining the specific volume of a magnetic field line. It is found that the flute modes are stabilized by the minimum-B magnetic field even with a divertor mirror although its stabilizing effects are weaker than that without the divertor mirror. The flute instability enhances the radial transport by intermittently repeating the growing up and down of the Fourier amplitude of the flute instability in time.

  6. Research study to determine critical optical/mechanical properties of materials considered for selection as substrates for the primary mirror on a large telescope

    NASA Technical Reports Server (NTRS)

    Slomba, A. F.; Goggin, W. R.

    1972-01-01

    An investigation was conducted to evaluate the stability of a specific low expansion glass-ceramic material relative to its use as a large, lightweight mirror substrate for diffraction-limited spaceborne optical applications. These evaluations were made on a segment (0.44 meter diameter by 0.31 meter thick) of a 2 to 3 meter diameter mirror blank. The dimensional stability of this mirror was measured interferometrically before and after lightweighting, as a function of rough machining, etching, thermal environment, and support configuration. A special computer analysis program was used to plot the coefficients corresponding to aberrations with sixfold symmetry (caused by the mirror's self-weight deflection on a three point support). The objective was to enhance the test sensitivity. Results indicate that any such effects due to self-weight deflection are of the order of 0.015 lambda rms. The rms and peak-to-peak figure changes associated with each processing operation are summarized.

  7. Demonstration of Flying Mirror with Improved Efficiency

    SciTech Connect

    Pirozhkov, Alexander S.; Kando, Masaki; Fukuda, Yuji; Chen Liming; Daito, Izuru; Ogura, Koichi; Homma, Takayuki; Hayashi, Yukio; Kotaki, Hideyuki; Sagisaka, Akito; Mori, Michiaki; Koga, James K.; Kawachi, Tetsuya; Kiriyama, Hiromitsu; Okada, Hajime; Kawase, Keigo; Kameshima, Takashi; Nishimori, Nobuyuki; Kimura, Toyoaki; Tajima, Toshiki

    2009-07-25

    A strongly nonlinear wake wave driven by an intense laser pulse can act as a partially reflecting relativistic mirror (the flying mirror)[S. V. Bulanov, et al., Bulletin of the Lebedev Physics Institute, No. 6, 9 (1991); S. V. Bulanov, et al., Phys. Rev. Lett. 91, 085001 (2003)]. Upon reflection from such mirror, a counter-propagating optical-frequency laser pulse is directly converted into high-frequency radiation, with a frequency multiplication factor approx4gamma{sup 2}(the double Doppler effect). We present the results of recent experiment in which the photon number in the reflected radiation was at least several thousand times larger than in our proof-of-principle experiment [M. Kando, et al., Phys. Rev. Lett. 99, 135001 (2007); A. S. Pirozhkov, et al., Phys. Plasmas 14, 123106 (2007)]. The flying mirror holds promise of generating intense coherent ultrashort XUV and x-ray pulses that inherit their temporal shape and polarization from the original optical-frequency (laser) pulses. Furthermore, the reflected radiation bears important information about the reflecting wake wave itself, which can be used for its diagnostics.

  8. Design of Off-Axis PIAACMC Mirrors

    NASA Technical Reports Server (NTRS)

    Pluzhnik, Eugene; Guyon, Olivier; Belikov, Ruslan; Kern, Brian; Bendek, Eduardo

    2015-01-01

    The Phase-Induced Amplitude Apodization Complex Mask Coronagraph (PIAACMC) provides an efficient way to control diffraction propagation effects caused by the central obstruction/segmented mirrors of the telescope. PIAACMC can be optimized in a way that takes into account both chromatic diffraction effects caused by the telescope obstructed aperture and tip/tilt sensitivity of the coronagraph. As a result, unlike classic PIAA, the PIAACMC mirror shapes are often slightly asymmetric even for an on-axis configuration and require more care in calculating off-axis shapes when an off-axis configuration is preferred. A method to design off-axis PIAA mirror shapes given an on-axis mirror design is presented. The algorithm is based on geometrical ray tracing and is able to calculate off-axis PIAA mirror shapes for an arbitrary geometry of the input and output beams. The method is demonstrated using the third generation PIAACMC design for WFIRST-AFTA (Wide Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets) telescope. Geometrical optics design issues related to the off-axis diffraction propagation effects are also discussed.

  9. Microinstabilities in the Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William

    2005-01-01

    The gasdynamic mirror has been proposed as a concept which could form the basis of a highly efficient fusion rocket engine. Gasdynamic mirrors differ from most other mirror type plasma confinement schemes in that they have much larger aspect ratios and operate at somewhat higher plasma densities. There are several types of instabilities which are known to plague mirror type confinement schemes. These instabilities fall into two general classes. One class of instability is the Magnetohdrodynamic or MHD instability which induces gross distortions in the plasma geometry. The other class of instability is the "loss cone" microinstability which leads to general plasma turbulence. The "loss cone" microinstability is caused by velocity space asymmetries resulting from the loss of plasma having constituent particle velocities within the angle of the magnetic mirror "loss cone." These instabilities generally manifest themselves in high temperature, moderately dense plasmas. The present study indicates that a GDM configured as a rocket engine might operate in a plasma regine where microinstabilities could potentially be significant.

  10. Microinstabilities in the Gasdynamic Mirror Propulsion System

    NASA Technical Reports Server (NTRS)

    Emrich, William

    2005-01-01

    The gasdynamic mirror has been proposed as a concept which could form the basis of a highly efficient fusion rocket engine. Gasdynamic mirrors differ from most other mirror type plasma confinement schemes in that they have much larger aspect ratios and operate at somewhat higher plasma densities. There are several types of instabilities which are known to plague mirror type confinement schemes. These instabilities fall into two general classes. One class of instability is the Magnetohydrodynamic or MHD instability which induces gross distortions in the plasma geometry. The other class of instability is the "loss cone" microinstability which leads to general plasma turbulence. The "loss cone" microinstability is caused by velocity space asymmetries resulting from the loss of plasma having constituent particle velocities within the angle of the magnetic mirror "loss cone." These instabilities generally manifest themselves in high temperature, moderately dense plasmas. The present study indicates that a GDM configured as a rocket engine might operate in a plasma regime where microinstabilities could potentially be significant.

  11. Advances in Tandem Mirror fusion power reactors

    SciTech Connect

    Perkins, L.J.; Logan, B.G.

    1986-05-20

    The Tandem Mirror exhibits several distinctive features which make the reactor embodiment of the principle very attractive: Simple low-technology linear central cell; steady-state operation; high-..beta.. operation; no driven current or disruptions; divertorless operation; direction conversion of end-loss power; low-surface heat loads; and advanced fusion fuel capability. In this paper, we examine these features in connection with two tandem mirror reactor designs, MARS and MINIMARS, and several advanced reactor concepts including the wall-stabilized reactor and the field-reversed mirror. With a novel compact end plug scheme employing octopole stabilization, MINIMARS is expressly designed for short construction times, factory-built modules, and a small (600 MWe) but economic reactor size. We have also configured the design for low radioactive afterheat and inherent/passive safety under LOCA/LOFA conditions, thereby obviating the need for expensive engineered safety systems. In contrast to the complex and expensive double-quadrupole end-cell of the MARS reactor, the compact octopole end-cell of MINIMARS enables ignition to be achieved with much shorter central cell lengths and considerably improves the economy of scale for small (approx.250 to 600 MWe) tandem mirror reactors. Finally, we examine the prospects for realizing the ultimate potential of the tandem mirror with regard to both innovative configurations and novel neutron energy conversion schemes, and stress that advanced fuel applications could exploit its unique reactor features.

  12. Optomechanical design software for segmented mirrors

    NASA Astrophysics Data System (ADS)

    Marrero, Juan

    2016-08-01

    The software package presented in this paper, still under development, was born to help analyzing the influence of the many parameters involved in the design of a large segmented mirror telescope. In summary, it is a set of tools which were added to a common framework as they were needed. Great emphasis has been made on the graphical presentation, as scientific visualization nowadays cannot be conceived without the use of a helpful 3d environment, showing the analyzed system as close to reality as possible. Use of third party software packages is limited to ANSYS, which should be available in the system only if the FEM results are needed. Among the various functionalities of the software, the next ones are worth mentioning here: automatic 3d model construction of a segmented mirror from a set of parameters, geometric ray tracing, automatic 3d model construction of a telescope structure around the defined mirrors from a set of parameters, segmented mirror human access assessment, analysis of integration tolerances, assessment of segments collision, structural deformation under gravity and thermal variation, mirror support system analysis including warping harness mechanisms, etc.

  13. LSST secondary mirror system final design

    NASA Astrophysics Data System (ADS)

    Neill, Douglas R.; Bogan, Gregory; Zajac, Dale; Araujo, Constanza; Gressler, William J.; DeVries, Joe; Hileman, Edward A.; Lotz, Paul J.; Mills, Dave; Thomas, Sandrine; Sebring, Thomas A.; Sebag, Jacques; Warner, Mike; Wiecha, Oliver

    2016-07-01

    The Large Synoptic Survey Telescope (LSST) has a 10 degrees square field of view which is achieved through a 3 mirror optical system comprised of an 8.4 meter primary, 3.5 meter secondary (M2) and a 5 meter tertiary mirror. The M2 is a 100mm thick meniscus convex asphere. The mirror surface is actively controlled by 72 axial electromechanical actuators (axial actuators). Transverse support is provided by 6 active tangential electromechanical actuators (tangent links). The final design has been completed by Harris Corporation. They are also providing the fabrication, integration and testing of the mirror cell assembly, as well as the figuring of the mirror. The final optical surface will be produced by ion figuring. All the actuators will experience 1 year of simulated life testing to ensure that they can withstand the rigorous demands produced by the LSST survey mission. Harris Corporation is providing optical surface metrology to demonstrate both the quality of the optical surface and the correctablility produced by the axial actuators.

  14. Mirror Advanced Reactor Study (MARS): executive summary and overview

    SciTech Connect

    Logan, B.G.; Perkins, L.J.; Gordon, J.D.

    1984-07-01

    Two self-consistent MARS configurations are discussed - a 1200-MWe commercial electricity-generating plant and a synguels-generating plant that produces hydrogen with an energy equivalent to 26,000 barrels of oil per day. The MARS machine emphasizes the attractive features of the tandem mirror concept, including steady-state operation, a small-diameter high-beta plasma, a linear central cell with simple low-maintenance blankets, low first-wall heat fluxes (<10 W/cm/sup 2/), no driven plasma currents or associated disruptions, natural halo impurity diversion, and direct conversion of end-loss charged-particle power. The MARS electric plant produces 2600 MW of fusion power in a 130-m-long central cell. Advanced tandem-mirror plasma-engineering concepts, a high-efficiency liquid lithium-lead (Li/sub 17/Pb/sub 83/) blanket, and efficient direct electrical conversion of end loss power combine to produce a high net plant efficiency of 36%. With a total capital cost of $2.9 billion (constant 1983 dollars), the MARS electric plant produces busbar electricity at approx. 7 cents/kW-hour. The MARS synfuels plant produces 3500 MW of fusion power in a 150-m-long central cell. A helium-gas-cooled silicon carbide pebble-bed blanket provides high-temperature (1000/sup 0/C) heat to a thermochemical water-splitting cycle and the resulting hydrogen is catalytically converted to methanol for distribution. With a total capital cost of $3.6 billion (constant 1983 dollars), the synfuels plant produces methanol fuel at about $1.7/gal. The major features of the MARS reactor include sloshing-ion thermal barrier plugs for efficient plasma confinement, a high efficiency blanket, high-field (24-T) choke cells, drift pumping for trapped plasma species, quasi-optical electron-cyclotron resonant heating (ECRH) systems, and a component gridless direct converter.

  15. Forming mandrels for making lightweight x-ray mirrors

    NASA Astrophysics Data System (ADS)

    Blake, Peter N.; Saha, Timo; Zhang, William W.; O'Dell, Stephen; Kester, Thomas; Jones, William

    2011-09-01

    Future x-ray astronomical missions, similar to the proposed International X-ray Observatory (IXO), will utilize replicated mirrors to reduce both mass and production costs. Accurately figured and measured molds (called mandrels) - on which the mirror substrates are thermally formed, replicating the surface of the mandrels - are essential to enable these missions. The Optics Branches of the Goddard Space Flight Center (GSFC) and Marshall Space Flight Center (MSFC) have developed fabrication processes along with metrologies that yield high-precision mandrels; and through the SBIR program, they encourage small businesses to attack parts of the remaining problems. The Goddard full-aperture mandrel polisher (the MPM-500) has been developed to a level where mandrel surfaces match the 1.5 arcsec HPD level allocation in a 5 arcsec telescope program. This paper reviews this current technology and describes a pilot program to design a suite of machine tools and process parameters capable of producing many hundreds of these precision objects. A major challenge is to keep mid-spatial frequency errors below 2 nm rms - a severe specification; but we must also note the factors which work to our advantage: e.g., how the figure departs from a pure cone by only one micron, and how the demanding figure specifications which apply in the axial direction are relaxed by an order of magnitude in the azimuthal. Careful study of other large optical fabrication programs in the light of these challenges and advantages has yielded a realistic plan for the economical production of mandrels that meet program requirements in both surface and quantity.

  16. Mirror, Mirror by the Stairs: The Impact of Mirror Exposure on Stair versus Elevator Use in College Students.

    PubMed

    Hodgin, Katie L; Graham, Dan J

    2016-01-01

    Previous research has indicated that self-awareness-inducing mirrors can successfully incite behaviors that align with one's personal values, such as helping others. Other research has found a large discrepancy between the high percentage of young adults who report valuing the healthfulness of physical activity (PA) and the low percentage who actually meet PA participation standards. However, few studies have examined how mirror exposure and both perceived and actual body size influence highly valued PA participation among college students. The present study assessed stair versus elevator use on a western college campus and hypothesized that mirror exposure would increase the more personally healthy transportation method of stair use. In accordance with previous research, it was also hypothesized that males and those with a lower body mass index (BMI) would be more likely to take the stairs, and that body size distorting mirrors would impact the stair-elevator decision. One hundred sixty-seven students (51% male) enrolled in an introductory psychology course were recruited to take a survey about their "transportation choices" at an indoor campus parking garage. Participants were individually exposed to either no mirror, a standard full-length mirror, or a full-length mirror manipulated to make the reflected body size appear either slightly thinner or slightly wider than normal before being asked to go to the fourth floor of the garage for a survey. Participants' choice of floor-climbing method (stairs or elevator) was recorded, and they were administered an Internet-based survey assessing demographic information, BMI, self-awareness, perceived body size, and other variables likely to be associated with stair use. Results from logistic regression analyses revealed that participants who were not exposed to a mirror [odds ratios (OR) = 0.37, 95% CI: 0.14-0.96], males (OR = 0.33, 95% CI: 0.13-0.85), those with lower BMI (OR = 0.84, 95% CI: 0.71-0.99), those

  17. Mirror, Mirror by the Stairs: The Impact of Mirror Exposure on Stair versus Elevator Use in College Students

    PubMed Central

    Hodgin, Katie L.; Graham, Dan J.

    2016-01-01

    Previous research has indicated that self-awareness-inducing mirrors can successfully incite behaviors that align with one’s personal values, such as helping others. Other research has found a large discrepancy between the high percentage of young adults who report valuing the healthfulness of physical activity (PA) and the low percentage who actually meet PA participation standards. However, few studies have examined how mirror exposure and both perceived and actual body size influence highly valued PA participation among college students. The present study assessed stair versus elevator use on a western college campus and hypothesized that mirror exposure would increase the more personally healthy transportation method of stair use. In accordance with previous research, it was also hypothesized that males and those with a lower body mass index (BMI) would be more likely to take the stairs, and that body size distorting mirrors would impact the stair–elevator decision. One hundred sixty-seven students (51% male) enrolled in an introductory psychology course were recruited to take a survey about their “transportation choices” at an indoor campus parking garage. Participants were individually exposed to either no mirror, a standard full-length mirror, or a full-length mirror manipulated to make the reflected body size appear either slightly thinner or slightly wider than normal before being asked to go to the fourth floor of the garage for a survey. Participants’ choice of floor-climbing method (stairs or elevator) was recorded, and they were administered an Internet-based survey assessing demographic information, BMI, self-awareness, perceived body size, and other variables likely to be associated with stair use. Results from logistic regression analyses revealed that participants who were not exposed to a mirror [odds ratios (OR) = 0.37, 95% CI: 0.14–0.96], males (OR = 0.33, 95% CI: 0.13–0.85), those with lower BMI (OR = 0.84, 95% CI: 0

  18. Four-mirror extreme ultraviolet (EUV) lithography projection system

    DOEpatents

    Cohen, Simon J; Jeong, Hwan J; Shafer, David R

    2000-01-01

    The invention is directed to a four-mirror catoptric projection system for extreme ultraviolet (EUV) lithography to transfer a pattern from a reflective reticle to a wafer substrate. In order along the light path followed by light from the reticle to the wafer substrate, the system includes a dominantly hyperbolic convex mirror, a dominantly elliptical concave mirror, spherical convex mirror, and spherical concave mirror. The reticle and wafer substrate are positioned along the system's optical axis on opposite sides of the mirrors. The hyperbolic and elliptical mirrors are positioned on the same side of the system's optical axis as the reticle, and are relatively large in diameter as they are positioned on the high magnification side of the system. The hyperbolic and elliptical mirrors are relatively far off the optical axis and hence they have significant aspherical components in their curvatures. The convex spherical mirror is positioned on the optical axis, and has a substantially or perfectly spherical shape. The spherical concave mirror is positioned substantially on the opposite side of the optical axis from the hyperbolic and elliptical mirrors. Because it is positioned off-axis to a degree, the spherical concave mirror has some asphericity to counter aberrations. The spherical concave mirror forms a relatively large, uniform field on the wafer substrate. The mirrors can be tilted or decentered slightly to achieve further increase in the field size.

  19. Long Focal Length Large Mirror Fabrication System

    NASA Technical Reports Server (NTRS)

    Bennett, H. E.

    2003-01-01

    The goals of this ambitious program are (1) to develop systems to make large superpolished optical mirrors, (2) to develop low scatter polishing techniques using centrifugal elutriation, (3) to develop a means of measuring scatter at any point on the mirror, (4) to polish a Hindle sphere to measure the optical figure of a one meter diameter convex mandrel, and (5) to fabricate low scatter, large adaptive optic graphite filled, cyanate ester replica transfer mirrors using these mandrels. Deliverables are a 30 cm diameter superpolished composite AO mirror. We fabricated a 1/3rd meter superpolished zerodur flat mandrel and with the support of our major subcontractor, Composite Mirror Applications Inc (CMA) we have demonstrated a 30 cm lightweight cyanate ester mirror with an rms microroughness between 0.6 and 0.8 nm and 8 faceplate influence function of 5 cm. The influence function was chosen to be comparable to the atmospheric correlation coefficient r(sub 0) which is about 5 cm at sea level. There was no print-thru of the graphite fibers in the cyanate ester surface (the bane of many previous efforts to use cyanate ester mirrors). Our subcontractor has devised a means for developing a 30-50 nm thick layer of graphite free pure ester resin on the surface of the mirrors. This graphite fiber filled material has a thermal expansion coefficient in the 10(exp -8) centimeter per Kelvin range (the same range of expansion coefficient as Zerodur and ULE glasses) and does not take up water and swell, so it is a nearly ideal mirror material in these areas. Unfortunately for these 0.8mm thick faceplates, the number of plies is not enough to result in isometric coverage. Isolated figure irregularities can appear, making it necessary to go to thicker faceplates. The influence function will then only approximate the length of r(sub 0), at higher altitudes or longer wavelengths. The influence function goes as the cube of the thickness, so we are now making a faceplate optimized for

  20. Space Adaptation of Active Mirror Segment Concepts

    NASA Technical Reports Server (NTRS)

    Ames, Gregory H.

    1999-01-01

    This report summarizes the results of a three year effort by Blue Line Engineering Co. to advance the state of segmented mirror systems in several separate but related areas. The initial set of tasks were designed to address the issues of system level architecture, digital processing system, cluster level support structures, and advanced mirror fabrication concepts. Later in the project new tasks were added to provide support to the existing segmented mirror testbed at Marshall Space Flight Center (MSFC) in the form of upgrades to the 36 subaperture wavefront sensor. Still later, tasks were added to build and install a new system processor based on the results of the new system architecture. The project was successful in achieving a number of important results. These include the following most notable accomplishments: 1) The creation of a new modular digital processing system that is extremely capable and may be applied to a wide range of segmented mirror systems as well as many classes of Multiple Input Multiple Output (MIMO) control systems such as active structures or industrial automation. 2) A new graphical user interface was created for operation of segmented mirror systems. 3) The development of a high bit rate serial data loop that permits bi-directional flow of data to and from as many as 39 segments daisy-chained to form a single cluster of segments. 4) Upgrade of the 36 subaperture Hartmann type Wave Front Sensor (WFS) of the Phased Array Mirror, Extendible Large Aperture (PAMELA) testbed at MSFC resulting in a 40 to 5OX improvement in SNR which in turn enabled NASA personnel to achieve many significant strides in improved closed-loop system operation in 1998. 5) A new system level processor was built and delivered to MSFC for use with the PAMELA testbed. This new system featured a new graphical user interface to replace the obsolete and non-supported menu system originally delivered with the PAMELA system. The hardware featured Blue Line's new stackable

  1. Mirrors Steer NASA in the Right Direction

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Left Hand Design completed the production of the fine-steering mirror technology through 1995 Phase I and 1996 Phase II SBIR contracts with JPL's Interferometric Astronomy group. Presently, the work resulting from the collaboration with NASA represents the company's main line of products for the commercial sector. Aerospace-related applications include: image motion compensation; interceptor seekers for the U.S. Army and Navy; Earth observation and resource monitoring from spacecraft and airborne platforms; space astronomy; helicopter-based surveillance; and interferometric metrology. Left Hand Design's fine-steering mirrors have also penetrated the commercial marketplace with non-aerospace applications, including laser communications, video cameras, infrared inspection, solar observatories, and bathymeters. These cost-effective, commercial mirrors perform a variety of functions, such as scanning, alignment, chopping, tracking, pointing, and beam stabilization. Potential future applications include laser surgery and photolithography.

  2. Relativistic mirrors in laser plasmas (analytical methods)

    NASA Astrophysics Data System (ADS)

    Bulanov, S. V.; Esirkepov, T. Zh; Kando, M.; Koga, J.

    2016-10-01

    Relativistic flying mirrors in plasmas are realized as thin dense electron (or electron-ion) layers accelerated by high-intensity electromagnetic waves to velocities close to the speed of light in vacuum. The reflection of an electromagnetic wave from the relativistic mirror results in its energy and frequency changing. In a counter-propagation configuration, the frequency of the reflected wave is multiplied by the factor proportional to the Lorentz factor squared. This scientific area promises the development of sources of ultrashort x-ray pulses in the attosecond range. The expected intensity will reach the level at which the effects predicted by nonlinear quantum electrodynamics start to play a key role. We present an overview of theoretical methods used to describe relativistic flying, accelerating, oscillating mirrors emerging in intense laser-plasma interactions.

  3. Topological mirror insulators in one dimension

    NASA Astrophysics Data System (ADS)

    Lau, Alexander; van den Brink, Jeroen; Ortix, Carmine

    2016-10-01

    We demonstrate the existence of topological insulators in one dimension (1D) protected by mirror and time-reversal symmetries. They are characterized by a nontrivial Z2 topological invariant defined in terms of the "partial" polarizations, which we show to be quantized in the presence of a 1D mirror point. The topological invariant determines the generic presence or absence of integer boundary charges at the mirror-symmetric boundaries of the system. We check our findings against spin-orbit coupled Aubry-André-Harper models that can be realized, e.g., in cold-atomic Fermi gases loaded in one-dimensional optical lattices or in density- and Rashba spin-orbit-modulated semiconductor nanowires. In this setup, in-gap end-mode Kramers doublets appearing in the topologically nontrivial state effectively constitute a double-quantum dot with spin-orbit coupling.

  4. Mirror mode structures in the Saturn's MSH

    NASA Astrophysics Data System (ADS)

    Gutynska, O.; Genot, V. N.; André, N.; Jacquey, C.; Budnik, E.

    2012-12-01

    The origin and shape of mirror structures are discussed using the observations of magnetic field and plasma data from Cassini spacecraft during 2004-2007 years. We find that these structures show typically large anticorrelation between plasma and magnetic field fluctuations together with large occurrence frequency of magnetic holes closer to the magnetopause. To propose a process of formation and evolution of mirror structures in the Saturn's magnetosheath we attempt to model the age of magnetic structures with an analytical flow model based on an approach similar to the Earth's magnetosheath case. We discuss dependence of scale sizes of mirror mode structures on different parameters. This work has been performed in the frame of the FP7 Europlanet project.

  5. Double relativistic electron-accelerating mirror

    SciTech Connect

    Andreev, Aleksandr A; Platonov, Konstantin Yu

    2013-05-31

    A numerical simulation of the interaction of a laser pulse with ultrathin targets has revealed a possibility of generating thin dense relativistic electron layers. The maximum kinetic energy of the electron mirror can be gained using an optimal combination of the target thickness and the laser pulse intensity and duration. It is proposed to use an additional (second) laser target, located at an optimal distance from the first target to cut off the laser pulse from the electron layer when the latter gains a maximum kinetic energy. This relativistic electron mirror can be used for efficient generation of 'hard' coherent radiation via counter reflection of an additional (probe) laser pulse from the mirror. (interaction of laser radiation with matter. laser plasma)

  6. Design considerations regarding ellipsoidal mirror based reflectometers.

    PubMed

    Benson, Michael R; Marciniak, Michael A

    2013-11-18

    Hemi-ellipsoidal mirrors are used in reflection-based measurements due to their ability to collect light scattered from one focal point at the other. In this paper, a radiometric model of this energy transfer is derived for arbitrary mirror and detector geometries. This model is used to examine the imaging characteristics of the mirror away from focus for both diffuse and specular light. The radiometric model is applied to several detector geometries for measuring the Directional Hemispherical Reflectance for both diffuse and specular samples. The angular absorption characteristics of the detector are then applied to the measurement to address measurement accuracy for diffuse and specular samples. Examining different detector configurations shows the effectiveness of flat detectors at angles ranging from normal to 50°, and that multifaceted detectors can function from normal incidence to grazing angles.

  7. Progress in the tandem mirror program

    NASA Astrophysics Data System (ADS)

    Fowler, T. K.; Borchers, R. R.

    1981-09-01

    Experimental results in TMX have confirmed the basic principles of the tandem mirror concept. A center cell particle confinement parameter eta tau approximately one hundred billion cu cm obtained at ion temperatures around 100 eV, which is a hundred fold improvement over single mirrors at the same temperatures. For TMX these results were obtained at peak beta values in the center cell in the range 10 to 40%, not yet limited by MHD activity, and ion cyclotron resonant heating in the Phaedrus tandem mirror experiment has produced beta values approximately 25%, which is several times the ideal MHD limit for that device. In addition, it was demonstrated that the end fan chambers of TMX simultaneously isolate the hot electrons from the end walls, provide adequate pumping and conveniently dispose of the exhaust plasma energy either by thermal deposition on the end wall or by direct conversion to electricity (at 48% efficiency in agreement with calculations).

  8. Gasdynamic Mirror (GDM) Fusion Propulsion Engine Experiment

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The Gasdynamic Mirror, or GDM, is an example of a magnetic mirror-based fusion propulsion system. Its design is primarily consisting of a long slender solenoid surrounding a vacuum chamber that contains plasma. The bulk of the fusion plasma is confined by magnetic field generated by a series of toroidal-shaped magnets in the center section of the device. the purpose of the GDM Fusion Propulsion Experiment is to confirm the feasibility of the concept and to demonstrate many of the operational characteristics of a full-size plasma can be confined within the desired physical configuration and still reman stable. This image shows an engineer from Propulsion Research Technologies Division at Marshall Space Flight Center inspecting solenoid magnets-A, an integrate part of the Gasdynamic Mirror Fusion Propulsion Engine Experiment.

  9. Massive Particle Reflection from Moving Mirrors

    NASA Astrophysics Data System (ADS)

    Sfarti, Adrian

    2016-09-01

    We investigate the reflection of massive particles from moving mirrors. The adoption of the formalism based on the energy-momentum allowed us to derive the most general set of formulas, valid for massive and, in the limit, also for massless particles. We show that the momentum change of the reflecting particle always lies along the normal to the mirror, independent of the mirror speed. The subject is interesting not only to physicists designing concentrators for fascicles of massive particles and electron microscopes but also to computer scientists working in raytracing operating in the photon sector. The paper, far from being only theoretical, has profound and novel practical applications in both domains of engineering design and computer science.

  10. Machine Learning and Radiology

    PubMed Central

    Wang, Shijun; Summers, Ronald M.

    2012-01-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers. PMID:22465077

  11. The Basic Anaesthesia Machine

    PubMed Central

    Gurudatt, CL

    2013-01-01

    After WTG Morton's first public demonstration in 1846 of use of ether as an anaesthetic agent, for many years anaesthesiologists did not require a machine to deliver anaesthesia to the patients. After the introduction of oxygen and nitrous oxide in the form of compressed gases in cylinders, there was a necessity for mounting these cylinders on a metal frame. This stimulated many people to attempt to construct the anaesthesia machine. HEG Boyle in the year 1917 modified the Gwathmey's machine and this became popular as Boyle anaesthesia machine. Though a lot of changes have been made for the original Boyle machine still the basic structure remains the same. All the subsequent changes which have been brought are mainly to improve the safety of the patients. Knowing the details of the basic machine will make the trainee to understand the additional improvements. It is also important for every practicing anaesthesiologist to have a thorough knowledge of the basic anaesthesia machine for safe conduct of anaesthesia. PMID:24249876

  12. The basic anaesthesia machine.

    PubMed

    Gurudatt, Cl

    2013-09-01

    After WTG Morton's first public demonstration in 1846 of use of ether as an anaesthetic agent, for many years anaesthesiologists did not require a machine to deliver anaesthesia to the patients. After the introduction of oxygen and nitrous oxide in the form of compressed gases in cylinders, there was a necessity for mounting these cylinders on a metal frame. This stimulated many people to attempt to construct the anaesthesia machine. HEG Boyle in the year 1917 modified the Gwathmey's machine and this became popular as Boyle anaesthesia machine. Though a lot of changes have been made for the original Boyle machine still the basic structure remains the same. All the subsequent changes which have been brought are mainly to improve the safety of the patients. Knowing the details of the basic machine will make the trainee to understand the additional improvements. It is also important for every practicing anaesthesiologist to have a thorough knowledge of the basic anaesthesia machine for safe conduct of anaesthesia.

  13. First results of an auxiliary electron cyclotron resonance heating experiment in the GDT magnetic mirror

    NASA Astrophysics Data System (ADS)

    Bagryansky, P. A.; Kovalenko, Yu. V.; Savkin, V. Ya.; Solomakhin, A. L.; Yakovlev, D. V.

    2014-08-01

    The axially symmetric magnetic mirror device gas-dynamic trap (GDT, Budker Institute, Novosibirsk) has recently demonstrated a tangible increase in plasma electron temperature. According to laser scattering, a value of 0.4 keV has been achieved (a twofold increase). In addition to standard machine operation, utilizing a 5 MW neutral beam injection, a newly installed electron cyclotron resonance heating (ECRH) system was employed (54.5 GHz, 0.4 MW). The reported progress in electron temperature, along with previous experiments, which demonstrated plasma confinement at beta as high as 60%, is a significant advancement towards an energy efficient fusion neutron source based on GDT physics.

  14. Novel high-bandwidth bimorph deformable mirrors

    NASA Astrophysics Data System (ADS)

    Griffith, Michael S.; Laycock, Leslie C.; Archer, Nick J.

    2004-12-01

    Adaptive Optics (AO) is a critical underpinning technology for future laser delivery (including free-space optical communications), target illumination and imaging systems. It measures and compensates for optical distortion caused by transmission through the atmosphere, resulting in the ability to deploy smaller lasers and identify targets at greater ranges. One of the key components in an AO system is the wavefront modifier, which acts on the incoming or outgoing beam to counter the effects of the atmosphere. BAE SYSTEMS Advanced Technology Centre is developing multi-element bimorph deformable mirrors for such an applications. Our initial designs were based on a standard construction and exhibited a resonant frequency of 1kHz with a maximum stroke of +/-20μm for an active aperture of 50mm. These devices were limited by the necessity to have a 'dead space' between the inner active area and the mirror boundary; this ensured that both the requirements for the stroke and the fixed boundary conditions could be met simultaneously. However, there was a significant penalty to pay in terms of bandwidth, which is inversely proportional to the square of the full mirror diameter. In a series of iteration steps, we have created novel mounting arrangements that reduce dead space and thus provide the optimum trade-off between bandwidth and stroke. These schemes include supporting the mirror from underneath, rather than at its edge. As a result, models of 60mm active diameter mirrors predict a resonance in excess of 5kHz, combined with a maximum stroke greater than +/-40μm. This paper will discuss a number of different mirror designs and present experimental results for recently assembled devices.

  15. Adaptive MOEMS mirrors for medical imaging

    NASA Astrophysics Data System (ADS)

    Fayek, Reda; Ibrahim, Hany

    2007-03-01

    This paper presents micro-electro-mechanical-systems (MEMS) optical elements with high angular deflection arranged in arrays to perform dynamic laser beam focusing and scanning. Each element selectively addresses a portion of the laser beam. These devices are useful in medical and research applications including laser-scanning microscopy, confocal microscopes, and laser capture micro-dissection. Such laser-based imaging and diagnostic instruments involve complex laser beam manipulations. These often require compound lenses and mirrors that introduce misalignment, attenuation, distortion and light scatter. Instead of using expensive spherical and aspherical lenses and/or mirrors for sophisticated laser beam manipulations, we propose scalable adaptive micro-opto-electro-mechanical-systems (MOEMS) arrays to recapture optical performance and compensate for aberrations, distortions and imperfections introduced by inexpensive optics. A high-density array of small, individually addressable, MOEMS elements is similar to a Fresnel mirror. A scalable 2D array of micro-mirrors approximates spherical or arbitrary surface mirrors of different apertures. A proof of concept prototype was built using PolyMUMP TM due to its reliability, low cost and limited post processing requirements. Low-density arrays (2x2 arrays of square elements, 250x250μm each) were designed, fabricated, and tested. Electrostatic comb fingers actuate the edges of the square mirrors with a low actuation voltage of 20 V - 50 V. CoventorWare TM was used for the design, 3D modeling and motion simulations. Initial results are encouraging. The array is adaptive, configurable and scalable with low actuation voltage and a large tuning range. Individual element addressability would allow versatile uses. Future research will increase deflection angles and maximize reflective area.

  16. Optical testing of a gamma-ray telescope mirror

    NASA Astrophysics Data System (ADS)

    Udupa, D. V.; Shukla, R. P.; Saksena, G. D.

    1993-09-01

    A large size concave mirror for use in the gamma-ray telescope TACTIC was tested. Focal length of the concave spherical mirror of diameter 600 mm was measured to be 401.2 cm using the Ronchi test. The surface accuracy of the mirror was estimated to be about Lambda/2 by visual observation of the fringes obtained. The spot size of the mirror for a nearly collimated beam was measured to be about 0.5 mm, whereas the computed size of the spot for a spherical mirror is about 0.1 mm. The reflectivity of the mirror was measured to be about 83% in the visible region.

  17. Spherical mirror grazing incidence x-ray optics

    NASA Technical Reports Server (NTRS)

    Cash, Jr., Webster C. (Inventor)

    1997-01-01

    An optical system for x-rays combines at least two spherical or near spherical mirrors for each dimension in grazing incidence orientation to provide the functions of a lens in the x-ray region. To focus x-ray radiation in both the X and the Y dimensions, one of the mirrors focusses the X dimension, a second mirror focusses the Y direction, a third mirror corrects the X dimension by removing comatic aberration and a fourth mirror corrects the Y dimension. Spherical aberration may also be removed for an even better focus. The order of the mirrors is unimportant.

  18. Active Beam Shaping System and Method Using Sequential Deformable Mirrors

    NASA Technical Reports Server (NTRS)

    Norman, Colin A. (Inventor); Pueyo, Laurent A. (Inventor)

    2015-01-01

    An active optical beam shaping system includes a first deformable mirror arranged to at least partially intercept an entrance beam of light and to provide a first reflected beam of light, a second deformable mirror arranged to at least partially intercept the first reflected beam of light from the first deformable mirror and to provide a second reflected beam of light, and a signal processing and control system configured to communicate with the first and second deformable mirrors. The first deformable mirror, the second deformable mirror and the signal processing and control system together provide a large amplitude light modulation range to provide an actively shaped optical beam.

  19. Alignment and focus of mirrored facets of a heliosat

    DOEpatents

    Yellowhair, Julius E; Ho, Clifford Kuofei; Diver, Richard B; Moss, Timothy A

    2013-11-12

    Various technologies pertaining to aligning and focusing mirrored facets of a heliostat are described herein. Updating alignment and/or focus of mirrored facets is undertaken through generation of a theoretical image, wherein the theoretical image is indicative of a reflection of the target via the mirrored facets when the mirrored facets are properly aligned. This theoretical image includes reference points that are overlaid on an image of the target as reflected by the mirrored facets of the heliostat. A technician adjusts alignment/focus of a mirrored facet by causing reflected reference markings to become aligned with the reference points in the theoretical image.

  20. Machine Tool Software

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A NASA-developed software package has played a part in technical education of students who major in Mechanical Engineering Technology at William Rainey Harper College. Professor Hack has been using (APT) Automatically Programmed Tool Software since 1969 in his CAD/CAM Computer Aided Design and Manufacturing curriculum. Professor Hack teaches the use of APT programming languages for control of metal cutting machines. Machine tool instructions are geometry definitions written in APT Language to constitute a "part program." The part program is processed by the machine tool. CAD/CAM students go from writing a program to cutting steel in the course of a semester.

  1. Quantum Boltzmann Machine

    NASA Astrophysics Data System (ADS)

    Kulchytskyy, Bohdan; Andriyash, Evgeny; Amin, Mohammed; Melko, Roger

    The field of machine learning has been revolutionized by the recent improvements in the training of deep networks. Their architecture is based on a set of stacked layers of simpler modules. One of the most successful building blocks, known as a restricted Boltzmann machine, is an energetic model based on the classical Ising Hamiltonian. In our work, we investigate the benefits of quantum effects on the learning capacity of Boltzmann machines by extending its underlying Hamiltonian with a transverse field. For this purpose, we employ exact and stochastic training procedures on data sets with physical origins.

  2. Moving M2 mirror without pointing offset.

    NASA Astrophysics Data System (ADS)

    Ragazzoni, R.; Bortoletto, F.

    1991-09-01

    Moving the secondary mirror M2 to introduce an amount of decentering coma is one of the tasks of active optics. The authors show that this target is accomplished with high accuracy rotating the mirror around a point located near, but not exactly at the center of curvature of M2. Ray tracing results are compared to analytical ones in the case of the Italian Galileo telescope, that will be equipped with an high precision M2 driving device; the close matching with the analytical calculations is demonstrated.

  3. Stress analysis of spherical-mirror panels

    SciTech Connect

    Parks, V J; Sanford, R J

    1982-04-01

    An experimental analysis is reported of the stresses that occur in elastically deformed, spherically curved glass mirrors for solar energy applications. Bending and membrance stresses generated in forming the glass and the effects of springback are analyzed. In addition, thermal stresses caused by focusing the sun's rays on a small region of the mirrors are analyzed. Methods used in the analysis included the use of grids, photoelasticity, and strain gages. Results of the analysis are compared with a theoretical analysis performed by Shelltech Associates in a parallel effort.

  4. Lightweight Deployable Mirrors with Tensegrity Supports

    NASA Technical Reports Server (NTRS)

    Zeiders, Glenn W.; Bradford, Larry J.; Cleve, Richard C.

    2004-01-01

    The upper part of Figure 1 shows a small-scale prototype of a developmental class of lightweight, deployable structures that would support panels in precise alignments. In this case, the panel is hexagonal and supports disks that represent segments of a primary mirror of a large telescope. The lower part of Figure 1 shows a complete conceptual structure containing multiple hexagonal panels that hold mirror segments. The structures of this class are of the tensegrity type, which was invented five decades ago by artist Kenneth Snelson. A tensegrity structure consists of momentfree compression members (struts) and tension members (cables). The structures of this particular developmental class are intended primarily as means to erect large segmented primary mirrors of astronomical telescopes or large radio antennas in outer space. Other classes of tensegrity structures could also be designed for terrestrial use as towers, masts, and supports for general structural panels. An important product of the present development effort is the engineering practice of building a lightweight, deployable structure as an assembly of tensegrity modules like the one shown in Figure 2. This module comprises two octahedral tensegrity subunits that are mirror images of each other joined at their plane of mirror symmetry. In this case, the plane of mirror symmetry is both the upper plane of the lower subunit and the lower plane of the upper subunit, and is delineated by the midheight triangle in Figure 2. In the configuration assumed by the module to balance static forces under mild loading, the upper and lower planes of each sub-unit are rotated about 30 , relative to each other, about the long (vertical) axis of the structure. Larger structures can be assembled by joining multiple modules like this one at their sides or ends. When the module is compressed axially (vertically), the first-order effect is an increase in the rotation angle, but by virtue of the mirror arrangement, the net

  5. Tandem mirror thermal barrier experimental program plan

    SciTech Connect

    Coensgen, F.H.; Drake, R.P.; Simonen, T.C.

    1980-01-02

    This report describes an experimental plan for the development of the Tandem Mirror Thermal Barrier. Included is: (1) a description of thermal barrier related physics experiments; (2) thermal barrier related experiments in the existing TMX and Phaedrus experiments; (3) a thermal barrier TMX upgrade; and (4) initiation of investigations of axisymmetric magnetic geometry. Experimental studies of the first two items are presently underway. Results are expected from the TMX upgrade by the close of 1981 and from axisymmetric tandem mirror experiments at the end of 1983. Plans for Phaedrus upgrades are developing for the same period.

  6. Tandem-mirror program: status and projection

    SciTech Connect

    Van Atta, C.M.

    1981-03-12

    Construction of MFTF-B is scheduled for completion in 1985. Results of experiments in TMX-U and MFTF-B will permit the design of the D-T burning tandem-mirror next-step facility (TMNS) in which physics issues will not be at issue. TMNS will be a facility for engineering research and development. The end cells of TMNS are expected to be appropriate for a tandem-mirror demonstration fusion reactor (TMR), construction of which should begin about 1986 for operation in the 1990's.

  7. Mirror writing and a dissociative identity disorder.

    PubMed

    Le, Catherine; Smith, Joyce; Cohen, Lewis

    2009-01-01

    Individuals with dissociative identity disorder (DID) have been known to show varied skills and talents as they change from one dissociative state to another. For example, case reports have described people who have changed their handedness or have spoken foreign languages during their dissociative states. During an interview with a patient with DID, a surprising talent emerged when she wrote a sentence for the Folstein Mini-Mental State Exam-mirror writing. It is not known whether her mirror writing had a deeper level of meaning; however, it does emphasize the idiosyncratic nature of dissociative identity disorder.

  8. Flute waves in a tandem mirror

    SciTech Connect

    Mikhailovskaya, L.V.

    1984-03-01

    Stability conditions are derived for flute waves in a short tandem mirror stabilized by end cells with a min B. The frequency spectrum of the flute waves is analyzed. Those conditions under which the resonant excitation of waves by ions and electrons must be taken into account are found. When end cells without a min B are added to a central mirror system, the system becomes destabilized as the result of resonant excitation of waves at a frequency near the precession frequency of ions having a finite energy distribution.

  9. Topology optimization design of space rectangular mirror

    NASA Astrophysics Data System (ADS)

    Qu, Yanjun; Wang, Wei; Liu, Bei; Li, Xupeng

    2016-10-01

    A conceptual lightweight rectangular mirror is designed based on the theory of topology optimization and the specific structure size is determined through sensitivity analysis and size optimization in this paper. Under the load condition of gravity along the optical axis, compared with the mirrors designed by traditional method using finite element analysis method, the performance of the topology optimization reflectors supported by peripheral six points are superior in lightweight ratio, structure stiffness and the reflective surface accuracy. This suggests that the lightweight method in this paper is effective and has potential value for the design of rectangular reflector.

  10. Beryllium deposition on International Thermonuclear Experimental Reactor first mirrors: Layer morphology and influence on mirror reflectivity

    SciTech Connect

    De Temmerman, G.; Baldwin, M. J.; Doerner, R. P.; Nishijima, D.; Seraydarian, R.; Schmid, K.; Kost, F.; Linsmeier, Ch.; Marot, L.

    2007-10-15

    Metallic mirrors will be essential components of the optical diagnostic systems in the International Thermonuclear Experimental Reactor (ITER). Reliability of these systems may be affected by mirror reflectivity changes induced by erosion and/or deposition of impurities (carbon, beryllium). The present study aims to assess the effect of beryllium (Be) deposition on the reflectivity of metallic mirrors and to collect data on the optical quality of these layers in terms of morphology, roughness, etc. Mirrors from molybdenum and copper were exposed in the PISCES-B linear plasma device to collect eroded material from graphite and beryllium targets exposed to beryllium-seeded deuterium plasma. After exposure, relative reflectivity of the mirrors was measured and different surface analysis techniques were used to investigate the properties of the deposited layers. Be layers formed in PISCES-B exhibit high levels of porosity which makes the reflectivity of the Be layers much lower than the reflectivity of pure Be. It is found that if Be deposition occurs on ITER first mirrors, the reflectivity of the coated mirrors will strongly depend on the layer morphology, which in turn depends on the deposition conditions.

  11. Fabrication Methods for Adaptive Deformable Mirrors

    NASA Technical Reports Server (NTRS)

    Toda, Risaku; White, Victor E.; Manohara, Harish; Patterson, Keith D.; Yamamoto, Namiko; Gdoutos, Eleftherios; Steeves, John B.; Daraio, Chiara; Pellegrino, Sergio

    2013-01-01

    Previously, it was difficult to fabricate deformable mirrors made by piezoelectric actuators. This is because numerous actuators need to be precisely assembled to control the surface shape of the mirror. Two approaches have been developed. Both approaches begin by depositing a stack of piezoelectric films and electrodes over a silicon wafer substrate. In the first approach, the silicon wafer is removed initially by plasmabased reactive ion etching (RIE), and non-plasma dry etching with xenon difluoride (XeF2). In the second approach, the actuator film stack is immersed in a liquid such as deionized water. The adhesion between the actuator film stack and the substrate is relatively weak. Simply by seeping liquid between the film and the substrate, the actuator film stack is gently released from the substrate. The deformable mirror contains multiple piezoelectric membrane layers as well as multiple electrode layers (some are patterned and some are unpatterned). At the piezolectric layer, polyvinylidene fluoride (PVDF), or its co-polymer, poly(vinylidene fluoride trifluoroethylene P(VDF-TrFE) is used. The surface of the mirror is coated with a reflective coating. The actuator film stack is fabricated on silicon, or silicon on insulator (SOI) substrate, by repeatedly spin-coating the PVDF or P(VDFTrFE) solution and patterned metal (electrode) deposition. In the first approach, the actuator film stack is prepared on SOI substrate. Then, the thick silicon (typically 500-micron thick and called handle silicon) of the SOI wafer is etched by a deep reactive ion etching process tool (SF6-based plasma etching). This deep RIE stops at the middle SiO2 layer. The middle SiO2 layer is etched by either HF-based wet etching or dry plasma etch. The thin silicon layer (generally called a device layer) of SOI is removed by XeF2 dry etch. This XeF2 etch is very gentle and extremely selective, so the released mirror membrane is not damaged. It is possible to replace SOI with silicon

  12. 16. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Interior, Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific Railroad Carlin Shops, view to south (90mm lens). Note the large segmental-arched doorway to move locomotives in and out of Machine Shop. - Southern Pacific Railroad, Carlin Shops, Roundhouse Machine Shop Extension, Foot of Sixth Street, Carlin, Elko County, NV

  13. Tunnel boring machine

    SciTech Connect

    Snyder, L. L.

    1985-07-09

    A tunnel boring machine for controlled boring of a curvilinear tunnel including a rotating cutter wheel mounted on the forward end of a thrust cylinder assembly having a central longitudinal axis aligned with the cutter wheel axis of rotation; the thrust cylinder assembly comprising a cylinder barrel and an extendable and retractable thrust arm received therein. An anchoring assembly is pivotally attached to the rear end of the cylinder barrel for anchoring the machine during a cutting stroke and providing a rear end pivot axis during curved cutting strokes. A pair of laterally extending, extendable and retractable arms are fixedly mounted at a forward portion of the cylinder barrel for providing lateral displacement in a laterally curved cutting mode and for anchoring the machine between cutting strokes and during straight line boring. Forward and rear transverse displacement and support assemblies are provided to facilitate cutting in a transversely curved cutting mode and to facilitate machine movement between cutting strokes.

  14. Molecular Machines: Nanoscale gadgets

    NASA Astrophysics Data System (ADS)

    Garcia-Garibay, Miguel A.

    2008-06-01

    Meeting their biological counterparts halfway, artificial molecular machines embedded in liquid crystals, crystalline solids and mesoporous materials are poised to meet the demands of the next generation of functional materials.

  15. Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

    SciTech Connect

    McGoldrick, P.R.

    1981-01-01

    The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control room consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed.

  16. Nonconventional ultra-precision manufacturing of ULE mirror surfaces using atmospheric reactive plasma jets

    NASA Astrophysics Data System (ADS)

    Arnold, Thomas; Böhm, Georg; Paetzelt, Hendrik

    2016-07-01

    In this paper we present a non-abrasive surface manufacturing technology suited for fast and efficient figuring of optical surfaces made of ULE (Corning Ultra Low Expansion) glass. Plasma Jet Machining (PJM) technology is based on an atmospheric chemical reactive plasma jet tool that locally interacts with the surface in order to remove material by chemical reactions forming volatile species. ULE has been proven to be suited for the PJM process. It has been found that the volume removal rate is approximately 25% higher than for fused silica and values up to 50mm3/min can be reached with our setup. Thus, figuring and figure error correction of large optics like mirror segments for earth based telescopes can be realized within a reasonable time. In the paper principles of the PJM process as well as ULE specific issues are discussed and machining results are presented.

  17. Development and investigation of a CPV module with Cassegrain mirror optics

    NASA Astrophysics Data System (ADS)

    Dreger, Max; Wiesenfarth, Maike; Kisser, Arne; Schmid, Tobias; Bett, Andreas W.

    2014-09-01

    One approach to concentrate the sunlight in concentrating photovoltaic (CPV) modules is using Cassegrain mirror optics. The advantage is that a passively cooled solar cell can be mounted to a large heat spreader that does not shade the primary optics. In addition, the height of the module, hence weight, can be low. The design was selected on the basis of the results of a design study comparing different CPV module approaches presented in [1]. In this work, we present the development of a new prototype micro dish module. First results of the characterization are shown. Besides of the electrical performance, a machined optics and an injection molded was investigated regarding sensitivity to misalignment errors between the optical elements as well as measurement of the acceptance angle in- and outdoors. The machined optics was used as reference.

  18. Doubly fed induction machine

    DOEpatents

    Skeist, S. Merrill; Baker, Richard H.

    2005-10-11

    An electro-mechanical energy conversion system coupled between an energy source and an energy load including an energy converter device having a doubly fed induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer coupled to the energy converter device to control the flow of power or energy through the doubly fed induction machine.

  19. Maraging Steel Machining Improvements

    DTIC Science & Technology

    2007-04-23

    APR 2007 2. REPORT TYPE Technical, Success Story 3. DATES COVERED 01-12-2006 to 23-04-2007 4. TITLE AND SUBTITLE Maraging Steel Machining...consumers of cobalt-strengthened maraging steel . An increase in production requires them to reduce the machining time of certain operations producing... maraging steel ; Success Stories 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 1 18. NUMBER OF PAGES 1 19a. NAME OF RESPONSIBLE

  20. Sealing intersecting vane machines

    DOEpatents

    Martin, Jedd N.; Chomyszak, Stephen M.

    2005-06-07

    The invention provides a toroidal intersecting vane machine incorporating intersecting rotors to form primary and secondary chambers whose porting configurations minimize friction and maximize efficiency. Specifically, it is an object of the invention to provide a toroidal intersecting vane machine that greatly reduces the frictional losses through intersecting surfaces without the need for external gearing by modifying the width of one or both tracks at the point of intermeshing. The inventions described herein relate to these improvements.