Science.gov

Sample records for fiber optical parametric

  1. Normal dispersion femtosecond fiber optical parametric oscillator.

    PubMed

    Nguyen, T N; Kieu, K; Maslov, A V; Miyawaki, M; Peyghambarian, N

    2013-09-15

    We propose and demonstrate a synchronously pumped fiber optical parametric oscillator (FOPO) operating in the normal dispersion regime. The FOPO generates chirped pulses at the output, allowing significant pulse energy scaling potential without pulse breaking. The output average power of the FOPO at 1600 nm was ∼60  mW (corresponding to 1.45 nJ pulse energy and ∼55% slope power conversion efficiency). The output pulses directly from the FOPO were highly chirped (∼3  ps duration), and they could be compressed outside of the cavity to 180 fs by using a standard optical fiber compressor. Detailed numerical simulation was also performed to understand the pulse evolution dynamics around the laser cavity. We believe that the proposed design concept is useful for scaling up the pulse energy in the FOPO using different pumping wavelengths. PMID:24104828

  2. Femtosecond fiber-feedback optical parametric oscillator.

    PubMed

    Südmeyer, T; Aus der Au, J; Paschotta, R; Keller, U; Smith, P G; Ross, G W; Hanna, D C

    2001-03-01

    We demonstrate what is to our knowledge the first synchronously pumped high-gain optical parametric oscillator (OPO) with feedback through a single-mode fiber. This device generates 2.3-2.7 W of signal power in 700-900-fs pulses tunable in a wavelength range from 1429 to 1473 nm. The necessary high gain was obtained from a periodically poled LiTaO(3) crystal pumped with as much as 8.2 W of power at 1030 nm from a passively mode-locked Yb:YAG laser with 600-fs pulse duration and a 35-MHz repetition rate. The fiber-feedback OPO setup is compact because most of the resonator feedback path consists of a standard telecom fiber. Because of the high parametric gain, the fiber-feedback OPO is highly insensitive to intracavity losses. For the same reason, the synchronization of the cavity with the pump laser is not critical, so active stabilization of the cavity length is not required. PMID:18040309

  3. Polarized fiber optical parametric amplification in randomly birefringent fibers.

    PubMed

    Wang, S H; Xu, Xinchuan; Wai, P K A

    2015-12-14

    A comprehensive theoretical model to investigate phase matching in degenerate polarized fiber optical parametric amplifiers (FOPAs) in randomly birefringent fibers is developed. We show that in the small signal region, simulation results from the proposed model agree well with the experimental results. It was also shown that four waves mixing (FWM) effect could compensate polarization mode dispersion (PMD) induced phase mismatch. Similar to counter-propagating fiber Raman amplifiers (FRAs), the degree of polarization of FOPAs approaches unity exponentially with the gain but at a larger rate 1/Γ. Thus larger polarization-pulling can be achieved in FOPAs than the counter-propagating FRAs for the same gain. PMID:26699064

  4. Fiber optical parametric amplifiers in optical communication systems

    PubMed Central

    Marhic (†), Michel E; Andrekson, Peter A; Petropoulos, Periklis; Radic, Stojan; Peucheret, Christophe; Jazayerifar, Mahmoud

    2015-01-01

    The prospects for using fiber optical parametric amplifiers (OPAs) in optical communication systems are reviewed. Phase-insensitive amplifiers (PIAs) and phase-sensitive amplifiers (PSAs) are considered. Low-penalty amplification at/or near 1 Tb/s has been achieved, for both wavelength- and time-division multiplexed formats. High-quality mid-span spectral inversion has been demonstrated at 0.64 Tb/s, avoiding electronic dispersion compensation. All-optical amplitude regeneration of amplitude-modulated signals has been performed, while PSAs have been used to demonstrate phase regeneration of phase-modulated signals. A PSA with 1.1-dB noise figure has been demonstrated, and preliminary wavelength-division multiplexing experiments have been performed with PSAs. 512 Gb/s have been transmitted over 6,000 km by periodic phase conjugation. Simulations indicate that PIAs could reach data rate x reach products in excess of 14,000 Tb/s × km in realistic wavelength-division multiplexed long-haul networks. Technical challenges remaining to be addressed in order for fiber OPAs to become useful for long-haul communication networks are discussed. PMID:25866588

  5. Thermal noise for SBS suppression in fiber optical parametric amplifiers

    NASA Astrophysics Data System (ADS)

    Mussot, Arnaud; Le Parquier, Marc; Szriftgiser, Pascal

    2010-06-01

    We demonstrate a new and simple solution to suppress stimulated Brillouin scattering in fiber optical parametric amplifiers. Cumbersome PRBS or sinusoidal generators used to broaden the pump spectrum are replaced by a filtered microwave noise source. Stimulated Brillouin scattering threshold can be increased up to large values still keeping an excellent quality of amplification of nonreturn to zero signals. The simplicity and the performances of this setup open the way for a wide variety of applications for FOPAs.

  6. Polarization pulling in Raman assisted fiber optical parametric amplifiers.

    PubMed

    Wang, S H; Xu, Xinchuan; Wai, P K A

    2016-04-01

    We proposed a theoretical model to investigate the polarization pulling effect in bi-directionally pumped degenerate Raman assisted fiber optical parameter amplifiers (RA-FOPAs) using randomly birefringent fibers. The contributions of chromatic dispersion, polarization mode dispersion (PMD), Raman gain, and nonlinear effects to the phase matching in RA-FOPAs are investigated. We characterize four different states of polarization pulling in RA-FOPAs. We found that broadband polarization attraction can be obtained in the optimum phase-matching state of the bi-directionally pumped RA-FOPAs when the parametric pump power is chosen to avoid deep saturation of the Raman gain. PMID:27136985

  7. Experimental demonstration of fiber optical parametric chirped-pulse amplification

    NASA Astrophysics Data System (ADS)

    Zhou, Yue; Cheung, Kim K. Y.; Chui, P. C.; Wong, Kenneth K. Y.

    2010-02-01

    A fiber optical parametric chirped-pulse amplifier (FOPCPA) is experimentally demonstrated. A 1.76 ps signal at 1542 nm with a peak power of 20 mW is broadened to 40 ps, and then amplified by a 100-ps pulsed pump at 1560 nm. The corresponding idler at 1578 nm is generated as the FOPCPA output. The same medium used to stretch the signal is deployed to compress the idler to 3.8 ps, and another spool of fiber is deployed to further compress the idler to 1.87 ps. The peak power of the compressed idler is 2 W, which corresponds to a gain of 20 dB.

  8. Response enhancement of deeply saturated fiber optic parametric amplifier via inhomogeneous fiber.

    PubMed

    Nissim, Ron R; Radic, Stojan

    2014-11-17

    Deeply saturated fiber optic parametric amplifiers can have very high performance. While it's a common practice to model the fiber as a longitudinally homogenous entity, we show that the inhomogeneous nature of the fiber leads to a greater performance level which is neither accessible nor accountable using the homogenous model. This indicates that some experimental results cannot be predicted using the homogenous fiber model, even in principle. Consequently, future studies on the performance limit of the system will have to include an inhomogeneous fiber model. PMID:25402022

  9. Locally Controlled Deeply Saturated Fiber Optic Parametric Amplifiers

    NASA Astrophysics Data System (ADS)

    Nissim, Ron Reuven

    A new class of highly efficient Optical Parametric Amplifiers (OPA) is explored in this dissertation, which have the potential to reduce the power requirement on the pump and enable new functionalities. This originates from the simple notion that figure of merit (FoM) of an OPA is proportional to the product of the pump power and amplifier's length and nonlinearity. Silica fibers have been developed for over five decades and offer unparalleled transparency. By merely extending the fiber, i.e. the amplifier's length, a high FoM amplifier can be formed while keeping the pump at a moderate, sub-Watt power level. Unfortunately, optical fibers are inherently non-uniform. Their core size fluctuates along the fiber on a nanometer scale which is on the order of the fiber's molecular constituents. It is currently established that the performance of a fiber-based OPA (FOPA) is dictated by its stochastic nature. In fact, given a moderate pump power level, the highly efficient OPA will be required to maintain a strict phase matching condition across hundreds of meters. Facing this challenge, this dissertation focuses on a locally-controlled, high FoM FOPA. A high FoM FOPA operates in the deeply saturated regime in which a weak signal saturates the amplifier and depletes the pump power, effectively generating an inverse response of the pump output power to the signal input power. Given FOPAs' inhomogeneous nature, the performance limit of deeply saturated FOPAs is studied. So far, FOPAs have been commonly treated as a uniform entity; however, this study discovers unique features of the system which originate from and are strongly influenced by the fiber's inhomogeneous nature. One major example is the non-reciprocal response of deeply saturated FOPAs. It was found that deeply saturated FOPAs perform very highly, as the pump can respond to a rapidly varying (sub-THz) weak (sub-muW) signal. This is a novel method which obtained orders of magnitude improvement over current

  10. Frequency-resolved noise figure measurements of phase (in)sensitive fiber optical parametric amplifiers.

    PubMed

    Malik, R; Kumpera, A; Lorences-Riesgo, A; Andrekson, P A; Karlsson, M

    2014-11-17

    We measure the frequency-resolved noise figure of fiber optical parametric amplifiers both in phase-insensitive and phase-sensitive modes in the frequency range from 0.03 to 3 GHz. We also measure the variation in noise figure due to the degradation in pump optical signal to noise ratio and also as a function of the input signal powers. Noise figure degradation due to stimulated Brillouin scattering is observed. PMID:25402025

  11. Multimodal coherent anti-Stokes Raman spectroscopic imaging with a fiber optical parametric oscillator

    PubMed Central

    Zhai, Yan-Hua; Goulart, Christiane; Sharping, Jay E.; Wei, Huifeng; Chen, Su; Tong, Weijun; Slipchenko, Mikhail N.; Zhang, Delong; Cheng, Ji-Xin

    2011-01-01

    We report on multimodal coherent anti-Stokes Raman scattering (CARS) imaging with a source composed of a femtosecond fiber laser and a photonic crystal fiber (PCF)-based optical parametric oscillator (FOPO). By switching between two PCFs with different zero dispersion wavelengths, a tunable signal beam from the FOPO covering the range from 840 to 930 nm was produced. By combining the femtosecond fiber laser and the FOPO output, simultaneous CARS imaging of a myelin sheath and two-photon excitation fluorescence imaging of a labeled axons in rat spinal cord have been demonstrated at the speed of 20 μs per pixel. PMID:21677908

  12. Parametric modeling in distributed optical fiber vibration sensing system for position determination

    NASA Astrophysics Data System (ADS)

    Wu, Hongyan; Wang, Jian; Jia, Bo

    2016-04-01

    Distributed optical fiber vibration sensing system is widely used as a monitoring system in communication cable and pipeline of long distances. When a vibration signal occurs at a particular position along the fiber, the response of the system, in the frequency domain, presents a series of periodic maxima and minima (or null frequencies). These minima depend on the position of the vibration signal along the fiber. Power spectral estimation methods are considered to denoise the power spectrum of the system and determine these minima precisely. The experimental results show higher accuracy of the position using a parametric model with appropriate selection of order p and q than just using fast Fourier transform algorithm.

  13. Ultra-wideband fiber optical parametric amplifier for spectrally-encoded microscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wei, Xiaoming; Tan, Sisi; Mussot, Arnaud; Kudlinski, Alexandre; Tsia, Kevin K.; Wong, Kenneth

    2016-03-01

    Fiber optical parametric amplifier (FOPA) has gained its popularity in the telecommunication systems at the 1.5-um window for its gain, bandwidth etc. Unfortunately, its practical application at the bio-favorable window, i.e. 1.0 um, still requires substantial efforts. Thus, here we report a versatile all-fiber optical parametric amplifier for life-science (OPALS) at 1.0 um as an add-on module for optical imaging system. The parametric gain fiber (photonic-crystal fiber (PCF), 110 m in length) is specially designed to reduce the longitudinal dispersion fluctuation, which yields a superior figure of merit, i.e. a total insertion loss of ~2.5 dB and a nonlinear coefficient of 34 /(W•km). Our OPALS delivers a superior performance in terms of gain (~158,000), bandwidth (>100 nm) and gain flatness (< 3-dB ripple). Experimentally, we show that: 1) a wavelength-varying quasi-monochrome pump achieves a 52-dB gain and 160-nm bandwidth, but at the expense of a larger gain-spectrum ripple, i.e. a bell-shaped; 2) the birefringence of the parametric gain medium, i.e. PCF in this case, can be utilized to improve the gain-spectrum flatness of OPALS by 10.5 dB, meanwhile a 100-nm bandwidth can be guaranteed; 3) the gain-spectrum flatness of OPALS can be further flattened by using a high-speed wavelength-sweeping pump, which exhibits a 110-nm flat gain spectrum with ripple less than 3 dB. Finally, we employ this versatile all-fiber OPALS as an add-on module to enhance the sensitivity of a spectrally-encoded microscope by 47 dB over an ultra-wide spectral range.

  14. Electronically and rapidly tunable fiber-integrable optical parametric oscillator for nonlinear microscopy.

    PubMed

    Brinkmann, Maximilian; Janfrüchte, Sarah; Hellwig, Tim; Dobner, Sven; Fallnich, Carsten

    2016-05-15

    We present a fiber-based optical parametric oscillator (FOPO) pumped by a fiber-coupled laser diode. The FOPO consisted of a photonic crystal fiber to convert the pump pulses via four-wave mixing and a dispersive resonator formed by a single-mode fiber. Via dispersion filtering, output pulses with a bandwidth of about 3 nm, a temporal duration of about 8 ps and a pulse energy of up to 22 nJ could be generated. By changing the repetition frequency of the pump laser diode by about ±1  kHz, the wavelength of the output pulses could be tuned between 1130 and 1310 nm within 8 μs, without the need to change the length of the resonator. Therewith, the FOPO should especially be suited for hyperspectral imaging, while its all-electronic control constitutes a promising approach to a turnkey and alignment-free light source. PMID:27176960

  15. Ultrafast, atto-Joule switch using fiber-optic parametric amplifier operated in saturation.

    PubMed

    Andrekson, Peter A; Sunnerud, Henrik; Oda, Shoichiro; Nishitani, Takashi; Yang, Jiang

    2008-07-21

    All-optical manipulation of signals carried by lightwaves is attractive because controlling the light directly can be more efficient, allows a multitude of signal formats, and can also prove most cost effective. We implemented a novel scheme for ultrafast optical switching using very small control energy that relies on the use of a saturated fiber-optic parametric amplifier. Approximately 19 aJ (150 photons) of control pulse energy was needed for 50% extinction of the signal which is three to four orders of magnitude smaller than in other all-optical switching demonstrations. This allows the consideration of novel practical approaches to implement all-optical switching devices and all-optical subsystems for telecommunications and other applications. PMID:18648409

  16. Tunable modulational instability sidebands via parametric resonance in periodically tapered optical fibers.

    PubMed

    Armaroli, Andrea; Biancalana, Fabio

    2012-10-22

    We analyze the modulation instability induced by periodic variations of group velocity dispersion and nonlinearity in optical fibers, which may be interpreted as an analogue of the well-known parametric resonance in mechanics. We derive accurate analytical estimates of resonant detuning, maximum gain and instability margins, significantly improving on previous literature on the subject. We also design a periodically tapered photonic crystal fiber, in order to achieve narrow instability sidebands at a detuning of 35 THz, above the Raman maximum gain peak of fused silica. The wide tunability of the resonant peaks by variations of the tapering period and depth will allow to implement sources of correlated photon pairs which are far-detuned from the input pump wavelength, with important applications in quantum optics. PMID:23187276

  17. High repetition rate fiber amplifier pumped sub-20 fs optical parametric amplifier.

    PubMed

    Rothhardt, J; Hädrich, S; Schimpf, D N; Limpert, J; Tünnermann, A

    2007-12-10

    We report on a high repetition rate noncollinear optical parametric amplifier system (NOPA) based on a cavity dumped Ti:Sapphire oscillator providing the signal, and an Ytterbium-doped fiber amplifier pumping the device. Temporally synchronized NOPA pump pulses are created via soliton generation in a highly nonlinear photonic crystal fiber. This soliton is fiber amplified to high pulse-energies at high repetition rates. The broadband Ti:Sapphire laser pulses are parametrically amplified either directly or after additional spectral broadening. The approach of fiber-based pump-pulse generation from a femtosecond laser, that emits in the spectral region of NOPA-gain, offers enhanced long-term stability and pulse quality compared to conventional techniques, such as signal pulse generation from a high power laser system via filamentation in bulk media. The presented system produces high-energy ultra-short pulses with pulse-durations down to 15.6 fs and pulse-energies up to 500 nJ at a repetition rate as high as 2 MHz. PMID:19550960

  18. A novel structure photonic crystal fiber based on bismuth-oxide for optical parametric amplification

    NASA Astrophysics Data System (ADS)

    Jin, Cang; Yuan, Jinhui; Yu, Chongxiu

    2010-11-01

    The heavy metal oxide glasses containing bismuth such as bismuth sesquioxide show unique high refractive index. In addition, the bismuth-oxide based glass does not include toxic elements such as Pb, As, Se, Te, and exhibits well chemical, mechanical and thermal stability. Hence, it is used to fabricate high nonlinear fiber for nonlinear optical application. Although the bismuth-oxide based high nonlinear fiber can be fusion-spliced to conventional silica fibers and have above advantages, yet it suffers from large group velocity dispersion because of material chromatic dispersion which restricts its utility. In regard to this, the micro-structure was introduced to adjust the dispersion of bismuth-oxide high nonlinear fiber in the 1550nm wave-band. In this paper, a hexagonal solid-core micro-structure is developed to balance its dispersion and nonlinearity. Our simulation and calculation results show that the bismuth-oxide based photonic crystal fiber has near zero dispersion around 1550nm where the optical parametric amplification suitable wavelength is. Its dispersion slop in the communication wavelength range is also relatively flat. Moreover, both nonlinear coefficient and model filed distribution were simulated, respectively.

  19. Broadband mid-infrared fiber optical parametric oscillator based on a three-hole suspended-core chalcogenide fiber.

    PubMed

    Bai, Hangyu; Yang, Xiong; Wei, Yizhen; Gao, Shiming

    2016-01-20

    A mid-infrared fiber optical parametric oscillator is proposed and designed based on a three-hole As(2)S(5) suspended-core fiber (SCF). The eigenmodes of the SCF are depicted and the pump condition for single-mode operation is analyzed. The zero-dispersion wavelength is shifted to 2 μm by tuning the core diameter of the SCF. Using the degenerate four-wave mixing coupled-wave equations, a tuning range of the idler wavelength from 2 to 5 μm and a maximum conversion efficiency of 19% are numerically predicted in a 0.1-m-long SCF pumped by a 2.7 W thulium-doped fiber laser. PMID:26835926

  20. A flexible receiver with fiber optical parametric amplifier in OCDMA-FSO communication system

    NASA Astrophysics Data System (ADS)

    Xia, Min; Yuan, Jin-hui; Sang, Xin-zhu; Yin, Xiao-li; Rao, Lan; Yu, Chong-xiu

    2014-11-01

    A new receiver is proposed, which uses the fiber optical parametric amplifier (FOPA) in optical code division multiple access (OCDMA) over free space optic (FSO) communication system. The noise tolerance as the performance index in this receiver is derived. The receiver can not only improve the noise tolerance but also change the pump data conveniently for adapting to the length variation of the coding sequence under a complex and fast-changing weather condition. The influence of different factors on the noise tolerance is analyzed, and a significant improvement of about 18.77 dB for the noise tolerance can be achieved when the pump power and the length of coding sequence are 5 W and 256, respectively.

  1. 110 nm versatile fiber optical parametric amplifier at 1.0 μm.

    PubMed

    Wei, Xiaoming; Tan, Sisi; Mussot, Arnaud; Kudlinski, Alexandre; Tsia, Kevin K; Wong, Kenneth K Y

    2015-09-01

    The fiber optical parametric amplifier (FOPA) has been well investigated and widely adopted at the telecommunication window, and outstanding progress has been achieved in areas such as high gain, wide bandwidths, and even flexible gain-spectrum shape. In contrast, a FOPA at the bio-favorable window, 1.0 μm, has been largely underexploited, especially for its relatively limited bandwidth. Here, we demonstrate an all-fiber single-pump FOPA at 1.0 μm with versatile performances, including ultrahigh gain (∼52  dB), wide bandwidth (∼110  nm), and good gain-spectrum flatness (∼3  dB). To showcase the practical applications, the FOPA is utilized to amplify the broadband optical image signal from a spectrally encoded microscopy, yielding a sensitivity enhancement of 47 dB. Thus, it is promising that this all-fiber versatile FOPA works well as an add-on module in boosting sensitivity for existing optical systems at a 1.0 μm window. PMID:26368719

  2. Amplification of ultra-short optical pulses in a two-pump fiber optical parametric chirped pulse amplifier.

    PubMed

    Mussot, Arnaud; Kudlinski, Alexandre; d'Augères, Patrick Beaure; Hugonnot, Emmanuel

    2013-05-20

    We demonstrate with realistic numerical simulations that fiber optical parametric chirped pulse amplification is able to amplify ultra-short optical pulses. Such amplifiers driven by two-pump waves can amplify pulse bandwidth twice as large as the one of a single pump configuration. We show that pulses as short as 50 fs can be directly amplified. In addition, we take benefit from the saturation regime to achieve spectral broadening which makes possible to reduce pulse duration down to 15 fs. PMID:23736440

  3. Numerical modeling of mid-infrared fiber optical parametric oscillator based on the degenerated FWM of tellurite photonic crystal fiber.

    PubMed

    Cheng, Huihui; Luo, Zhengqian; Ye, Chenchun; Huang, Yizhong; Liu, Chun; Cai, Zhiping

    2013-01-20

    Mid-infrared fiber optical parametric oscillators (MIR FOPOs) based on the degenerate four-wave mixing (DFWM) of tellurite photonic crystal fibers (PCFs) are proposed and modeled for the first time. Using the DFWM coupled-wave equations, numerical simulations are performed to analyze the effects of tellurite PCFs, single-resonant cavity, and pump source on the MIR FOPO performances. The numerical results show that: (1) although a longer tellurite PCF can decrease the pump threshold of MIR FOPOs to a few watts only, the high conversion-efficiency of MIR idler usually requires a short-length optimum PCF with low loss; (2) compared with the single-pass DFWM configurations of the MIR fiber sources published previously, the stable oscillation of signal light in single-resonant cavity can significantly promote the MIR idler output efficiency. With a suggested tellurite PCF as parametric gain medium, the theoretical prediction indicates that such a MIR FOPO could obtain a wide MIR-tunable range and a high conversion efficiency of more than 10%. PMID:23338203

  4. Quantum information tapping using a fiber optical parametric amplifier with noise figure improved by correlated inputs.

    PubMed

    Guo, Xueshi; Li, Xiaoying; Liu, Nannan; Ou, Z Y

    2016-01-01

    One of the important functions in a communication network is the distribution of information. It is not a problem to accomplish this in a classical system since classical information can be copied at will. However, challenges arise in quantum system because extra quantum noise is often added when the information content of a quantum state is distributed to various users. Here, we experimentally demonstrate a quantum information tap by using a fiber optical parametric amplifier (FOPA) with correlated inputs, whose noise is reduced by the destructive quantum interference through quantum entanglement between the signal and the idler input fields. By measuring the noise figure of the FOPA and comparing with a regular FOPA, we observe an improvement of 0.7 ± 0.1 dB and 0.84 ± 0.09 dB from the signal and idler outputs, respectively. When the low noise FOPA functions as an information splitter, the device has a total information transfer coefficient of Ts+Ti = 1.5 ± 0.2, which is greater than the classical limit of 1. Moreover, this fiber based device works at the 1550 nm telecom band, so it is compatible with the current fiber-optical network for quantum information distribution. PMID:27458089

  5. Quantum information tapping using a fiber optical parametric amplifier with noise figure improved by correlated inputs

    NASA Astrophysics Data System (ADS)

    Guo, Xueshi; Li, Xiaoying; Liu, Nannan; Ou, Z. Y.

    2016-07-01

    One of the important functions in a communication network is the distribution of information. It is not a problem to accomplish this in a classical system since classical information can be copied at will. However, challenges arise in quantum system because extra quantum noise is often added when the information content of a quantum state is distributed to various users. Here, we experimentally demonstrate a quantum information tap by using a fiber optical parametric amplifier (FOPA) with correlated inputs, whose noise is reduced by the destructive quantum interference through quantum entanglement between the signal and the idler input fields. By measuring the noise figure of the FOPA and comparing with a regular FOPA, we observe an improvement of 0.7 ± 0.1 dB and 0.84 ± 0.09 dB from the signal and idler outputs, respectively. When the low noise FOPA functions as an information splitter, the device has a total information transfer coefficient of Ts+Ti = 1.5 ± 0.2, which is greater than the classical limit of 1. Moreover, this fiber based device works at the 1550 nm telecom band, so it is compatible with the current fiber-optical network for quantum information distribution.

  6. Quantum information tapping using a fiber optical parametric amplifier with noise figure improved by correlated inputs

    PubMed Central

    Guo, Xueshi; Li, Xiaoying; Liu, Nannan; Ou, Z. Y.

    2016-01-01

    One of the important functions in a communication network is the distribution of information. It is not a problem to accomplish this in a classical system since classical information can be copied at will. However, challenges arise in quantum system because extra quantum noise is often added when the information content of a quantum state is distributed to various users. Here, we experimentally demonstrate a quantum information tap by using a fiber optical parametric amplifier (FOPA) with correlated inputs, whose noise is reduced by the destructive quantum interference through quantum entanglement between the signal and the idler input fields. By measuring the noise figure of the FOPA and comparing with a regular FOPA, we observe an improvement of 0.7 ± 0.1 dB and 0.84 ± 0.09 dB from the signal and idler outputs, respectively. When the low noise FOPA functions as an information splitter, the device has a total information transfer coefficient of Ts+Ti = 1.5 ± 0.2, which is greater than the classical limit of 1. Moreover, this fiber based device works at the 1550 nm telecom band, so it is compatible with the current fiber-optical network for quantum information distribution. PMID:27458089

  7. Bandwidth-efficient phase modulation techniques for stimulated Brillouin scattering suppression in fiber optic parametric amplifiers.

    PubMed

    Coles, J B; Kuo, B P-P; Alic, N; Moro, S; Bres, C-S; Chavez Boggio, J M; Andrekson, P A; Karlsson, M; Radic, S

    2010-08-16

    Two novel bandwidth efficient pump-dithering Stimulated Brillouin Scattering (SBS) suppression techniques are introduced. The techniques employ a frequency-hopped chirp and an RF noise source to impart phase modulation on the pumps of a two pump Fiber Optical Parametric Amplifier (FOPA). The effectiveness of the introduced techniques is confirmed by measurements of the SBS threshold increase and the associated improvements relative to the current state of the art. Additionally, the effect on the idler signal integrity is presented as measured following amplification from a two pump FOPA employing both techniques. The measured 0.8 dB penalty with pumps dithered by an RF noise source, after accruing 160 ps/nm of dispersion with 38 dB conversion gain in a two-pump FOPA is the lowest reported to date. PMID:20721202

  8. Multichannel fiber optic pressure sensor system for parametric emission monitoring in combustion engines

    NASA Astrophysics Data System (ADS)

    Poorman, Thomas J.; Kalashnikov, Sergey P.; Wlodarczyk, Marek T.; Daire, Adam; Goeke, Wayne; Kropp, Richard; Kamat, Pradip

    1995-09-01

    A multichannel fiber-optic combustion pressure sensor system is described dedicated to parametric emission monitoring systems (PEMS) for use in natural gas-fueled, stationary, and reciprocating engines. In view of the emerging 1995 emission regulations for large stationary engines, the natural gas pipeline operators have turned their attention to PEMS' for predicting and controlling the amount of polluting emissions such as NOx and HC. We present design considerations and performance data of a 8-channel pressure monitoring system employing fiber-optic combustion pressure sensors. The control/monitoring unit offers capabilities of sensor calibration, health monitoring, and real-time data acquisition. Using an engine position sensor trigger, the monitoring unit can calculate peak pressure, indicative mean pressure, and location of peak pressure. The system allows for 50 kHz, burst mode transfer of multisensor data to a host PC. We demonstrated performance data collected on three large-bore engines and long-term endurance test data. While initially intended for stationary engines, the system can be used in applications requiring portability including moving vehicles.

  9. Gain-saturated one-pump fiber optical parametric amplifiers in presence of longitudinal dispersion fluctuations.

    PubMed

    Bagheri, M; Pakarzadeh, H; Keshavarz, A

    2016-05-01

    In this paper, we investigate the impact of longitudinal dispersion fluctuations of the optical fiber on the gain spectrum and the saturation behavior of one-pump fiber-optical parametric amplifiers (1-P FOPAs). The gain spectra and the saturation curves of 1-P FOPAs are simulated by solving the coupled amplitude equations numerically and taking into account the dispersion fluctuations as a stochastic process with a given standard deviation and correlation length. Results show that the shape and the level of the gain spectrum and also the saturation power of 1-P FOPAs are considerably changed in the presence of dispersion fluctuations in comparison with the case when dispersion fluctuations are ignored. This feature is also totally different compared with the small-signal gain spectrum of the FOPA in the presence of dispersion fluctuations. Moreover, the value of the change in the gain and the saturation power depends strongly on the fluctuation parameters, i.e., the standard deviation and the correlation length. PMID:27140344

  10. High power mid-infrared continuous-wave optical parametric oscillator pumped by fiber lasers

    NASA Astrophysics Data System (ADS)

    Xu, Xiaojun; Li, Xiao; Liu, Lei; Shang, Yaping

    2015-02-01

    3~5μm mid-infrared laser has many important applications, such as gas detection, spectral analysis, remote sensing, medical treatment, and also in the military laser radar, infrared countermine, and so on. Optical parametric oscillator (OPO) is an efficient way to generate laser in this wavelength range, which has attracted the eyes of many people. In this paper, the recent development of mid-infrared OPO is overviewed. Meanwhile, detailed introduction on our recent work is given. Maximum idler output power of 34.2W at center wavelength of 3.35μm was obtained, to our knowledge, which is the new power record of the international public reporting for the continue-wave (CW) mid-infrared OPO. It is worth mentioning that the pump source, the quasi single-frequency (SF) narrow line width fiber laser, was also developed by our groups. According to the current status of research, some solutions is proposed in order to achieve higher power, narrower line width, and compact volume mid-infrared OPO in a wide tunable range.

  11. Optical frequency up-conversion of UWB monocycle pulse based on pulsed-pump fiber optical parametric amplifier

    NASA Astrophysics Data System (ADS)

    Li, Jia; Liang, Yu; Xu, Xing; Cheung, Kim K. Y.; Wong, Kenneth K. Y.

    2009-11-01

    We propose a method to realize frequency up-conversion of UWB monocycle pulse using pulsed-pump fiber optical parametric amplifier (OPA). The spectrum of the amplified signal contains many discrete frequency components which are separated by the modulation frequency of the pump. Each frequency components contain the same spectral information as that of the original signal. By selecting the first-order or higher-order frequency components of the amplified signal and beating in the photodetector, up-converted signal at different frequencies are obtained. We demonstrate frequency up-conversion of baseband UWB monocycle pulse from 3-GHz to 19-GHz in the experiment and frequency up-conversion of pseudo-random binary sequence (PRBS) signal from 3-GHz to 60-GHz in the simulation.

  12. Widely tunable parametric generation of picosecond visible and mid-infrared radiation in optical fibers

    NASA Astrophysics Data System (ADS)

    Giree, Achut; Jauregui, Cesar; Limpert, Jens; Tünnermann, Andreas

    2013-03-01

    Parametric generation in an endlessly single-mode photonic crystal fiber can be a simple and efficient way to generate tunable visible and mid-infrared radiation. In this manuscript we report on a visible light source that is tunable from 628nm to 661nm with up to 25% conversion efficiency. This was obtained by tuning the parametric pump from 1030nm to 1055nm in a 1.6m long LMA-10 PM photonic crystal fiber. At the same time, the source generates mid-infrared radiation that can be tuned from ~2.65μm to ~2.9μm. A further increase of the tunable range of both the visible and midinfrared is possible simply by extending the pump tuning range.

  13. Progress in optical parametric oscillators

    NASA Technical Reports Server (NTRS)

    Fan, Y. X.; Byer, R. L.

    1984-01-01

    It is pointed out that tunable coherent sources are very useful for many applications, including spectroscopy, chemistry, combustion diagnostics, and remote sensing. Compared with other tunable sources, optical parametric oscillators (OPO) offer the potential advantage of a wide wavelength operating range, which extends from 0.2 micron to 25 microns. The current status of OPO is examined, taking into account mainly advances made during the last decade. Attention is given to early LiNbO3 parametric oscillators, problems which have prevented wide use of parametric oscillators, the demonstration of OPO's using urea and AgGaS2, progress related to picosecond OPO's, a breakthrough in nanosecond parametric oscillators, the first demonstration of a waveguide and fiber parametric amplification and generation, the importance of chalcopyrite crystals, and theoretical work performed with the aim to understand the factors affecting the parametric oscillator performance.

  14. Investigation of laser induced parametric interactions in optical waveguides and fibers

    NASA Technical Reports Server (NTRS)

    Yu, C.

    1978-01-01

    Experimental and theoretical aspects of the laser pump depletion characteristics in an optical fiber due to stimulated Raman scattering, and stimulated Brillouin scattering were studied. A review is presented of research in fiber transmission accompanied by stimulated scattering. Results of experimental work with tunable dye lasers and argon lasers are presented. The spectral profiles of the laser pump and its transmitted light through the fiber are given.

  15. Broadband fiber-optical parametric amplification for ultrafast time-stretch imaging at 1.0 μm.

    PubMed

    Wei, Xiaoming; Lau, Andy K S; Xu, Yiqing; Zhang, Chi; Mussot, Arnaud; Kudlinski, Alexandre; Tsia, Kevin K; Wong, Kenneth K Y

    2014-10-15

    We demonstrate a broadband all-fiber-optical parametric amplifier for ultrafast time-stretch imaging at 1.0 μm, featured by its compact design, alignment-free, high efficiency, and flexible gain spectrum through fiber nonlinearity- and dispersion-engineering: specifically on a dispersion-stabilized photonic-crystal fiber (PCF) to achieve a net gain over 20 THz (75 nm) and a highest gain of ~6000 (37.5 dB). Another unique feature of the parametric amplifier, over other optical amplifiers, is the coherent generation of a synchronized signal replica (called idler) that can be exploited to offer an extra 3-dB gain by optically superposing the signal and idler. It further enhances signal contrast and temporal stability. For proof-of-concept purpose, ultrahigh speed and diffraction-limited time-stretch microscopy is demonstrated with a single-shot line-scan rate of 13 MHz based on the dual-band (signal and idler) detection. Our scheme can be extended to other established bioimaging modalities, such as optical coherence tomography, near infrared fluorescence, and photoacoustic imaging, where weak signal detection at high speed is required. PMID:25361137

  16. Demonstration of optical parametric gain generation in the 1 μm regime based on a photonic crystal fiber pumped by a picosecond mode-locked ytterbium-doped fiber laser

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Yang, Si-Gang; Wang, Xiao-Jian; Gou, Dou-Dou; Chen, Hong-Wei; Chen, Ming-Hua; Xie, Shi-Zhong

    2014-01-01

    We report the experimental demonstration of the optical parametric gain generation in the 1 μm regime based on a photonic crystal fiber (PCF) with a zero group velocity dispersion (GVD) wavelength of 1062 nm pumped by a homemade tunable picosecond mode-locked ytterbium-doped fiber laser. A broad parametric gain band is obtained by pumping the PCF in the anomalous GVD regime with a relatively low power. Two separated narrow parametric gain bands are observed by pumping the PCF in the normal GVD regime. The peak of the parametric gain profile can be tuned from 927 to 1038 nm and from 1099 to 1228 nm. This widely tunable parametric gain band can be used for a broad band optical parametric amplifier, large span wavelength conversion or a tunable optical parametric oscillator.

  17. High-power femtosecond fiber-feedback optical parametric oscillator based on periodically poled stoichiometric LiTaO3.

    PubMed

    Südmeyer, T; Innerhofer, E; Brunner, F; Paschotta, R; Usami, T; Ito, H; Kurimura, S; Kitamura, K; Hanna, D C; Keller, U

    2004-05-15

    We demonstrate a synchronously pumped high-gain optical parametric oscillator with feedback through a fiber, using a passively mode-locked Yb:YAG thin-disk laser as a pump source. We obtain as much as 19-W average signal power at a wavelength of 1.45 microm in 840-fs pulses and 7.8 W of idler power at 3.57 microm. The repetition rate of the pulses is 56 MHz, and the transverse beam quality of the generated signal is M2 < 1.6. PMID:15182002

  18. Third-order spontaneous parametric down-conversion in thin optical fibers as a photon-triplet source

    SciTech Connect

    Corona, Maria; Garay-Palmett, Karina; U'Ren, Alfred B.

    2011-09-15

    We study the third-order spontaneous parametric down-conversion (TOSPDC) process, as a means to generate entangled photon triplets. Specifically, we consider thin optical fibers as the nonlinear medium to be used as the basis for TOSPDC in configurations where phase matching is attained through the use of more than one fiber transverse modes. Our analysis in this paper, which follows from our earlier paper [Opt. Lett. 36, 190-192 (2011)], aims to supply experimentalists with the details required in order to design a TOSPDC photon-triplet source. Specifically, our analysis focuses on the photon triplet state, on the rate of emission, and on the TOSPDC phase-matching characteristics for the cases of frequency-degenerate and frequency nondegenerate TOSPDC.

  19. A real-time structural parametric identification system based on fiber optic sensing and neural network algorithms

    NASA Astrophysics Data System (ADS)

    Wu, Zhishen; Xu, Bin

    2003-07-01

    A structural parametric identification strategy based on neural networks algorithms using dynamic macro-strain measurements in time domain from a long-gage strain sensor by fiber optic sensing technique such as Fiber Bragg Grating (FBG) sensor is developed. An array of long-gage sensors is bounded on the structure to measure reliably and accurately macro-strains. By the proposed methodology, the structural parameter of stiffness can be identified. A beam model with known mass distribution is considered as an object structure. Without any eigenvalue analysis or optimization computation, the structural parameter of stiffness can be identified. First an emulator neural network is presented to identify the beam structure in current state. Free vibration macro-strain responses of the beam structure are used to train the emulator neural network. The trained emulator neural network can be used to forecast the free vibration macro-strain response of the beam structure with enough precision and decide the difference between the free vibration macro-strain responses of other assumed structure with different structural parameters and those of the original beam structure. The root mean square (RMS) error vector is presented to evaluate the difference. Subsequently, corresponding to each assumed structure with different structural parameters, the RMS error vector can be calculated. By using the training data set composed of the structural parameters and RMS error vector, a parametric evaluation neural network is trained. A beam structure is considered as an existing structure, based on the trained parametric evaluation neural network, the stiffness of the beam structure can be forecast. It is shown that the parametric identification strategy using macro-strain measurement from long-gage sensors has the potential of being a practical tool for a health monitoring methodology applied to civil engineering structures.

  20. Parametric Study of the Reflective Periodic Grating for In-Plane Displacement Measurement Using Optical Fibers

    PubMed Central

    Lee, Yeon-Gwan; Kim, Dae-Hyun; Kim, Chun-Gon

    2012-01-01

    This paper presents a technique for a simple sensing principle that can be used for the measurement of displacement. The proposed sensor head is composed of a reflective grating panel and an optical fiber as a transceiver. The simplified layout contributes to resolving the issues of space restraints during installation and complex cabling problems in transmission fiber optic sensors. In order to verify the effectiveness of the proposed technique, it is important to obtain the sinusoidal signal reflected from the grating for reasonable phase tracking. In the numerical analysis, a real wave based optical beam model is proposed for the extraction of predicted signal according to the grating width and ratio of reflection bar width to spacing. The grating pattern design to obtain a sine wave reflected sensor signal was determined within an R-square value of 0.98 after sine curve fitting analysis. Consequently, the proposed sensor principle achieved the in-plane displacement measurement with a maximum accuracy error of 5.34 μm. PMID:22666030

  1. Optical parametric chirped pulse amplification and spectral shaping of a continuum generated in a photonic band gap fiber.

    PubMed

    Hugonnot, E; Somekh, M; Villate, D; Salin, F; Freysz, E

    2004-05-31

    A chirped pulse, spectrally broadened in a photonic bandgap optical fiber by 120 fs Ti:Sapphire laser pulses, is parametrically amplified in a BBO crystal pumped by a frequency doubled nanosecond Nd:YAG laser pulse. Without changing the frequency of the Ti:Sapphire, a spectral tunability of the amplified pulses is demonstrated. The possibility to achieve broader spectral range amplification is confirmed for a non-collinear pump-signal interaction geometry. For optimal non-collinear interaction geometry, the pulse duration of the original and amplified pulse are similar. Finally, we demonstrate that the combination of two BBO crystals makes it possible to spectrally shape the amplified pulses. PMID:19475076

  2. Multipass optical parametric amplifier

    SciTech Connect

    Jeys, T.H.

    1996-08-01

    A compact, low-threshold, multipass optical parametric amplifier has been developed for the conversion of short-pulse (360-ps) 1064-nm Nd:YAG laser radiation into eye-safe 1572-nm radiation for laser ranging and radar applications. The amplifier had a threshold pump power of as low as 45{mu}J, and at three to four times this threshold pump power the amplifier converted 30{percent} of the input 1064-nm radiation into 1572-nm output radiation. {copyright} {ital 1996 Optical Society of America.}

  3. Fiber-laser-based, green-pumped, picosecond optical parametric oscillator using fan-out grating PPKTP.

    PubMed

    Chaitanya Kumar, S; Parsa, S; Ebrahim-Zadeh, M

    2016-01-01

    We report a stable, Yb-fiber-laser-based, green-pumped, picosecond optical parametric oscillator (OPO) for the near-infrared based on periodically poled potassium titanyl phosphate (PPKTP) nonlinear crystal, using fan-out grating design and operating near room temperature. The OPO is continuously tunable across 726-955 nm in the signal and 1201-1998 nm in the idler, resulting in a total signal plus idler wavelength coverage of 1026 nm by grating tuning at a fixed temperature. The device generates up to 580 mW of average power in the signal at 765 nm and 300 mW in the idler at 1338 nm, with an overall extraction efficiency of up to 52% and a pump depletion >76%. The extracted signal at 765 nm and idler at 1746 nm exhibit excellent passive power stability better than 0.5% and 0.8% rms, respectively, over 1 h with good beam quality in TEM00 mode profile. The output signal pulses have a Gaussian temporal duration of 13.2 ps, with a FWHM spectral bandwidth of 3.4 nm at 79.5 MHz repetition rate. Power scaling limitations of the OPO due to the material properties of PPKTP are studied. PMID:26696156

  4. High-power, fiber-laser-pumped, picosecond optical parametric oscillator based on MgO:sPPLT.

    PubMed

    Kumar, S Chaitanya; Ebrahim-Zadeh, M

    2011-12-19

    We report a stable, high-power, mid-infrared synchronously-pumped optical parametric oscillator (SPOPO) based on MgO:sPPLT, pumped by a 1064 nm, picosecond Yb-fiber laser operating at a repetition rate of 81.1 MHz. The singly resonant SPOPO is tunable over 1531-1642 nm (111 nm) in the near-infrared signal and 3022-3488 nm (466 nm) in the mid-infrared idler, providing a total tuning range of 577 nm. Careful optimization of output coupling results in a signal output power as high as 4.3 W at 1593 nm and a mid-infrared idler power of 2 W at 3204 nm for 13.4 W of pump power at a total extraction efficiency of 47%. The SPOPO can be operated near room temperature, down to 30 °C, and exhibits passive peak-to-peak power stability better than 8.6% at 1568 nm (signal) and 8.2% at 3310 nm (idler) over 13 hours at full power. The output signal pulses have duration of 17.5 ps, with a FWHM spectral bandwidth of 1.4 nm centered at 1568 nm. PMID:22274250

  5. Generation of multi-mode squeezed vacuum using pulse pumped fiber optical parametric amplifiers.

    PubMed

    Liu, Nannan; Liu, Yuhong; Li, Jiamin; Yang, Lei; Li, Xiaoying

    2016-02-01

    Multimode squeezed states are essential resources in quantum information processing and quantum metrology with continuous variables. Here we present the experimental generation of squeezed vacuum via the degenerate four wave mixing realized by pumping a piece of dispersion shifted fiber with mode-locked ultrafast pulse trains. The noise fluctuation is lower than the shot noise limit by 1.1 ± 0.08 dB (1.95 ± 0.17 dB after correction for detection losses). The detailed investigation illustrates that the results can be further improved by suppressing Raman scattering and by reshaping the spectrum of the local oscillator to achieve the required mode-matching of the homodyne detection system. Our study is useful for developing a compact fiber source of multi-mode squeezed vacuum. PMID:26906788

  6. High-power PPMgLN-based optical parametric oscillator pumped by a linearly polarized, semi-fiber-coupled acousto-optic Q-switched fiber master oscillator power amplifier.

    PubMed

    Chen, Tao; Jiang, Peipei; Yang, Dingzhong; Hu, Chengzhi; Wu, Bo; Shen, Yonghang

    2013-09-01

    We have experimentally demonstrated a periodically poled magnesium-oxide-doped lithium niobate (PPMgLN)-based, fiber-laser-pumped optical parametric oscillator (OPO) generating idler wavelength of 3.82 μm. The pump fiber laser was constructed with a linearly polarized, semi-fiber-coupled acousto-optic Q-switched fiber oscillator and a polarization-maintaining fiber amplifier with pulse duration of 190 ns at the highest output power. The OPO was specifically configured in single-pass, singly resonant linear cavity structure to avoid the damage risk of the pump fiber laser, which is always a serious issue in the fiber-laser-pumped, double-pass, singly oscillating structured OPOs. Under the highest pump power of 25 W, an idler average output power of 3.27 W with one-hour peak-to-peak instability of 5.2% was obtained. The measured M2 factors were 1.98 and 1.44 for horizontal and vertical axis, respectively. The high power stability and good beam quality demonstrated the suitability of such technology for practical application. PMID:24085093

  7. Optical Fibers

    NASA Astrophysics Data System (ADS)

    Ghatak, Ajoy; Thyagarajan, K.

    With the development of extremely low-loss optical fibers and their application to communication systems, a revolution has taken fiber glass place during the last 40 years. In 2001, using glass fibers as the transmission medium and lightwaves as carrier wave waves, information was transmitted at a rate more than 1 Tbit/s (which is roughly equivalent to transmission of about 15 million simultaneous telephone conversations) through one hair thin optical fiber. Experimental demonstration of transmission at the rate of 14 Tbit/s over a 160 km long single fiber was demonstrated in 2006, which is equivalent to sending 140 digital high definition movies in 1 s. Very recently record transmission of more than 100 Tbit/s over 165 km single mode fiber has been reported. These can be considered as extremely important technological achievements. In this chapter we will discuss the propagation characteristics of optical fibers with special applications to optical communication systems and also present some of the noncommunication applications such as sensing.

  8. Optimization of noncollinear optical parametric amplification

    NASA Astrophysics Data System (ADS)

    Schimpf, D. N.; Rothardt, J.; Limpert, J.; Tünnermann, A.

    2007-02-01

    Noncollinearly phase-matched optical parametric amplifiers (NOPAs) - pumped with the green light of a frequency doubled Yb-doped fiber-amplifier system 1, 2 - permit convenient generation of ultrashort pulses in the visible (VIS) and near infrared (NIR) 3. The broad bandwidth of the parametric gain via the noncollinear pump configuration allows amplification of few-cycle optical pulses when seeded with a spectrally flat, re-compressible signal. The short pulses tunable over a wide region in the visible permit transcend of frontiers in physics and lifescience. For instance, the resulting high temporal resolution is of significance for many spectroscopic techniques. Furthermore, the high magnitudes of the peak-powers of the produced pulses allow research in high-field physics. To understand the demands of noncollinear optical parametric amplification using a fiber pump source, it is important to investigate this configuration in detail 4. An analysis provides not only insight into the parametric process but also determines an optimal choice of experimental parameters for the objective. Here, the intention is to design a configuration which yields the shortest possible temporal pulse. As a consequence of this analysis, the experimental setup could be optimized. A number of aspects of optical parametric amplifier performance have been treated analytically and computationally 5, but these do not fully cover the situation under consideration here.

  9. High-power multichannel PPMgLN-based optical parametric oscillator pumped by a master oscillation power amplification-structured Q-switched fiber laser.

    PubMed

    Chen, Tao; Wei, Kaihua; Jiang, Peipei; Wu, Bo; Shen, Yonghang

    2012-10-01

    We experimentally demonstrated a compact fiber laser-pumped multichannel PPMgLN-based optical parametric oscillator (OPO) generating total OPO output power of 15.8, 15.2, 14.2, 12.9, and 8.8 W with idler output power of 4.7, 4.3, 4.1, 3.3, and 2.1 W at the wavelength of 3.43, 3.63, 3.72, 3.83, and 3.99 μm, respectively. The OPO was pumped by a fully fiberized polarization maintaining (PM) ytterbium-doped pulsed fiber master oscillation power amplifier (MOPA) operating at 1064 nm at a repetition rate of 65 kHz with effective pump power of 28.7 W. The MOPA system was constructed with an acousto-optic Q-switched fiber laser seed and only one stage PM fiber amplifier without any free space components, which makes the pump system compact and stable in the long-term. Comparisons on efficiencies and signal wavelength shifts between different channels showed that the idler absorption was the main factor preventing high average-power OPO operation with long idler wavelength. PMID:23033106

  10. Compact high power mid-infrared optical parametric oscillator pumped by a gain-switched fiber laser with "figure-of-h" pulse shape.

    PubMed

    Jiang, Peipei; Chen, Tao; Wu, Bo; Yang, Dingzhong; Hu, Chengzhi; Wu, Pinghui; Shen, Yonghang

    2015-02-01

    We demonstrate a compact high power mid-infrared (MIR) optical parametric oscillator (OPO) pumped by a gain-switched linearly polarized, pulsed fiber laser. The gain-switched fiber laser was constructed with a piece of Yb doped polarization maintaining (PM) fiber, a pair of fiber Bragg gratings written into the matched passive PM fiber and 6 pigtailed pump laser diodes working at 915 nm with 30 W output peak power each. By modulating the pulse width of the pump laser diode, simple pedestal-free pulse shape or pedestal-free trailing pulse shape ("figure-of-h" as we call it) could be achieved from the gain-switched fiber laser. The laser was employed as the pump of a two-channel, periodically poled magnesium oxide lithium niobate-based OPO system. High power MIR emission was generated with average output power of 5.15 W at 3.8 μm channel and 8.54 W at 3.3 μm channel under the highest pump power of 45 W. The corresponding pump-to-idler conversion efficiency was computed to be 11.7% and 19.1%, respectively. Experimental results verify a significant improvement to signal-to-idler conversion efficiency by using "figure-of-h" pulses over simple pedestal-free pulses. Compared to the master oscillator power amplifier (MOPA) fiber laser counterpart, the presented gain switched fiber laser is more attractive in OPO pumping due to its compactness and simplicity which are beneficial to construction of OPO systems for practical MIR applications. PMID:25836126

  11. Fiber optic coupled optical sensor

    DOEpatents

    Fleming, Kevin J.

    2001-01-01

    A displacement sensor includes a first optical fiber for radiating light to a target, and a second optical fiber for receiving light from the target. The end of the first fiber is adjacent and not axially aligned with the second fiber end. A lens focuses light from the first fiber onto the target and light from the target onto the second fiber.

  12. Fiber optic monitoring device

    DOEpatents

    Samborsky, James K.

    1993-01-01

    A device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information.

  13. Broadband high-power mid-IR femtosecond pulse generation from an ytterbium-doped fiber laser pumped optical parametric amplifier.

    PubMed

    Hu, Chengzhi; Chen, Tao; Jiang, PeiPei; Wu, Bo; Su, Jianjia; Shen, Yonghang

    2015-12-15

    We report on a high-power periodically poled MgO-doped lithium niobate (MgO:PPLN)-based femtosecond optical parametric amplifier (OPA), featuring a spectral seamless broadband mid-infrared (MIR) output. By modifying the initial chirp and spectrum of the mode-locked seed laser, the Yb fiber pump laser exhibits a final output power of 14 W with sub-200-fs pulse duration after power amplification and compression. When the OPA was seeded with a broadband amplified spontaneous emission (ASE) source, a damage-limited 0.6 W broadband MIR radiation was experimentally obtained under the pump power of 10.15 W at 82 MHz repetition rate, corresponding to an overall OPA conversion efficiency of 32.7%. The 3 dB bandwidth of the mid-IR idler was 291.9 nm, centering at 3.34 μm. PMID:26670509

  14. Widely tunable eye-safe laser by a passively Q-switched photonic crystal fiber laser and an external-cavity optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Chang, H. L.; Zhuang, W. Z.; Huang, W. C.; Huang, J. Y.; Huang, K. F.; Chen, Y. F.

    2011-09-01

    We report on a widely tunable passively Q-switched photonic crystal fiber (PCF) laser with wavelength tuning range up to 80 nm. The PCF laser utilizes an AlGaInAs quantum well/barrier structure as a saturable absorber and incorporates an external-cavity optical parametric oscillator (OPO) to achieve wavelength conversion. Under a pump power of 13.1 W at 976 nm, the PCF laser generated 1029-nm radiation with maximum output energy of 750 μJ and was incident into an external-cavity OPO. The output energy and peak power of signal wave was found to be 138 μJ and 19 kW, respectively. By tuning the temperature of nonlinear crystal, periodically poled lithium niobate (PPLN), in the OPO, the signal wavelength in eye-safe regime from 1513 to 1593 nm was obtained.

  15. Fiber optic temperature sensor

    NASA Technical Reports Server (NTRS)

    Sawatari, Takeo (Inventor); Gaubis, Philip A. (Inventor)

    2000-01-01

    A fiber optic temperature sensor uses a light source which transmits light through an optical fiber to a sensor head at the opposite end of the optical fiber from the light source. The sensor head has a housing coupled to the end of the optical fiber. A metallic reflective surface is coupled to the housing adjacent the end of the optical fiber to form a gap having a predetermined length between the reflective surface and the optical fiber. A detection system is also coupled to the optical fiber which determines the temperature at the sensor head from an interference pattern of light which is reflected from the reflective surface.

  16. Fiber optic temperature sensor

    NASA Technical Reports Server (NTRS)

    Sawatari, Takeo (Inventor); Gaubis, Philip A. (Inventor); Mattes, Brenton L. (Inventor); Charnetski, Clark J. (Inventor)

    1999-01-01

    A fiber optic temperature sensor uses a light source which transmits light through an optical fiber to a sensor head at the opposite end of the optical fiber from the light source. The sensor head has a housing coupled to the end of the optical fiber. A metallic reflective surface is coupled to the housing adjacent the end of the optical fiber to form a gap having a predetermined length between the reflective surface and the optical fiber. A detection system is also coupled to the optical fiber which determines the temperature at the sensor head from an interference pattern of light which is reflected from the reflective surface.

  17. Fiber optic connector

    DOEpatents

    Rajic, S.; Muhs, J.D.

    1996-10-22

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded are disclosed. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled. 3 figs.

  18. Fiber optic connector

    DOEpatents

    Rajic, Slobodan; Muhs, Jeffrey D.

    1996-01-01

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled.

  19. Frequency domain optical parametric amplification

    PubMed Central

    Schmidt, Bruno E.; Thiré, Nicolas; Boivin, Maxime; Laramée, Antoine; Poitras, François; Lebrun, Guy; Ozaki, Tsuneyuki; Ibrahim, Heide; Légaré, François

    2014-01-01

    Today’s ultrafast lasers operate at the physical limits of optical materials to reach extreme performances. Amplification of single-cycle laser pulses with their corresponding octave-spanning spectra still remains a formidable challenge since the universal dilemma of gain narrowing sets limits for both real level pumped amplifiers as well as parametric amplifiers. We demonstrate that employing parametric amplification in the frequency domain rather than in time domain opens up new design opportunities for ultrafast laser science, with the potential to generate single-cycle multi-terawatt pulses. Fundamental restrictions arising from phase mismatch and damage threshold of nonlinear laser crystals are not only circumvented but also exploited to produce a synergy between increased seed spectrum and increased pump energy. This concept was successfully demonstrated by generating carrier envelope phase stable, 1.43 mJ two-cycle pulses at 1.8 μm wavelength. PMID:24805968

  20. High-efficiency PPMgLN-based mid-infrared optical parametric oscillator pumped by a MOPA-structured fiber laser with long pulse duration

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Liu, Hao; Huang, Yuxiang; Shu, Rong

    2015-12-01

    We report our recent investigation on the conversion efficiency improvement of a PPMgLN-based single pump pass, singly resonant optical parametric oscillator (OPO) pumped by an acousto-optic Q-switched fiber MOPA. The impacts of the pump pulse duration and signal reflectivity on the pump-to-idler conversion efficiency were studied by numerically solving the coupled wave equations in the first place. The results revealed that longer pulse durations were beneficial to higher conversion efficiencies as long as the signal reflectivity of the OPO cavity was optimized accordingly. Experiments were carried out thereafter utilizing the optimal parameters obtained from the simulation. Idler powers of 4.7 and 3.81 W were achieved at 3.4 and 3.8 μm, respectively, under the highest pump power of 28 W with pump pulse duration of 240 ns. The experimental results were in good agreement with the calculated results. According to our simulation, higher conversion efficiency could be expected when such an OPO was pumped by pulses with even longer duration provided that the signal reflectivity of the output coupler was optimized under that pump condition.

  1. Degenerate four-wave mixing based all-optical wavelength conversion in a semiconductor optical amplifier and highly-nonlinear photonic crystal fiber parametric loop mirror

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Cheng, Tee Hiang; Yeo, Yong kee; Wang, Yixin; Xue, Lifang; Wang, Dawei; Yu, Xiaojun

    2008-11-01

    The idler is separated from the co-propagating pump in a degenerate four-wave mixing (DFWM) with a symmetrical parametric loop mirror (PALM), which is composed of two identical SOAs and a 70 m highly-nonlinear photonic crystal fiber (HN-PCF). The signal and pump are coupled into the symmetrical PALM from different ports, respectively. After the DFWM based wavelength conversion (WC) in the clockwise and anticlockwise, the idler exits from the signal port, while the pump outputs from its input port. Therefore, the pump is effectively suppressed in the idler channel without a high-speed tunable filter. Contrast to a traditional PALM, the DFWM based conversion efficiency is increased greatly, and the functions of the amplification and the WC are integrated in the smart SOA and HN-PCF PALM.

  2. Fiber optic monitoring device

    DOEpatents

    Samborsky, J.K.

    1993-10-05

    A device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information. 4 figures.

  3. Fiber optic monitoring device

    SciTech Connect

    Samborsky, J.K.

    1992-12-31

    This invention is comprised of a device for the purpose of monitoring light transmissions in optical fibers comprises a fiber optic tap that optically diverts a fraction of a transmitted optical signal without disrupting the integrity of the signal. The diverted signal is carried, preferably by the fiber optic tap, to a lens or lens system that disperses the light over a solid angle that facilitates viewing. The dispersed light indicates whether or not the monitored optical fiber or system of optical fibers is currently transmitting optical information.

  4. Fiber Optics Technology.

    ERIC Educational Resources Information Center

    Burns, William E.

    1986-01-01

    Discusses various applications of fiber optics technology: information systems, industrial robots, medicine, television, transportation, and training. Types of jobs that will be available with fiber optics training (such as electricians and telephone cable installers and splicers) are examined. (CT)

  5. Fiber optic chemical sensors

    NASA Astrophysics Data System (ADS)

    Jung, Chuck C.; McCrae, David A.; Saaski, Elric W.

    1998-09-01

    This paper provides a broad overview of the field of fiber optic chemical sensors. Several different types of fiber optic sensors and probes are described, and references are cited for each category discussed.

  6. Fiber Optics Instrumentation Development

    NASA Technical Reports Server (NTRS)

    Chan, Patrick Hon Man; Parker, Allen R., Jr.; Richards, W. Lance

    2010-01-01

    This is a general presentation of fiber optics instrumentation development work being conducted at NASA Dryden for the past 10 years and recent achievements in the field of fiber optics strain sensors.

  7. Fiber optics in adverse environments

    SciTech Connect

    Lyous, P.B.

    1982-01-01

    Radiation effects in optical fibers are considered, taking into account recent progress in the investigation of radiation resistant optical fibers, radiation damage in optical fibers, radiation-induced transient absorption in optical fibers, X-ray-induced transient attenuation at low temperatures in polymer clad silica (PCS) fibers, optical fiber composition and radiation hardness, the response of irradiated optical waveguides at low temperatures, and the effect of ionizing radiation on fiber-optic waveguides. Other topics explored are related to environmental effects on components of fiber optic systems, and radiation detection systems using optical fibers. Fiber optic systems in adverse environments are also discussed, giving attention to the survivability of Army fiber optics systems, space application of fiber optics systems, fiber optic wavelength multiplexing for civil aviation applications, a new fiber optic data bus topology, fiber optics for aircraft engine/inlet control, and application of fiber optics in high voltage substations.

  8. Two Fiber Optical Fiber Thermometry

    NASA Technical Reports Server (NTRS)

    Jones, Mathew R.; Farmer, Jeffery T.; Breeding, Shawn P.

    2000-01-01

    An optical fiber thermometer consists of an optical fiber whose sensing tip is given a metallic coating. The sensing tip of the fiber is essentially an isothermal cavity, so the emission from this cavity will be approximately equal to the emission from a blackbody. Temperature readings are obtained by measuring the spectral radiative heat flux at the end of the fiber at two wavelengths. The ratio of these measurements and Planck's Law are used to infer the temperature at the sensing tip. Optical fiber thermometers have high accuracy, excellent long-term stability and are immune to electromagnetic interference. In addition, they can be operated for extended periods without requiring re-calibration. For these reasons. it is desirable to use optical fiber thermometers in environments such as the International Space Station. However, it has recently been shown that temperature readings are corrupted by emission from the fiber when extended portions of the probe are exposed to elevated temperatures. This paper will describe several ways in which the reading from a second fiber can be used to correct the corrupted temperature measurements. The accuracy and sensitivity to measurement uncertainty will be presented for each method.

  9. Fiber optic sensors

    NASA Technical Reports Server (NTRS)

    Hesse, J.; Sohler, W.

    1984-01-01

    A survey of the developments in the field of fiber optics sensor technology is presented along with a discussion of the advantages of optical measuring instruments as compared with electronic sensors. The two primary types of fiber optics sensors, specifically those with multiwave fibers and those with monowave fibers, are described. Examples of each major sensor type are presented and discussed. Multiwave detectors include external and internal fiber optics sensors. Among the monowave detectors are Mach-Zender interferometers, Michelson interferometers, Sagnac interferometers (optical gyroscopes), waveguide resonators, and polarimeter sensors. Integrated optical sensors and their application in spectroscopy are briefly discussed.

  10. Specialty optical fibers: revisited

    NASA Astrophysics Data System (ADS)

    Romaniuk, Ryszard S.

    2011-10-01

    The paper contains description of chosen aspects of analysis and design of tailored optical fibers. By specialty optical fibers we understand here the fibers which have complex construction and which serve for the functional processing of optical signal rather than long distance transmission. Thus, they are called also instrumentation optical fibers. The following issues are considered: transmission properties, transformation of optical signal, fiber characteristics, fiber susceptibility to external reactions. The technology of tailored optical fibers offers a wider choice of the design tools for the fiber itself, and then various devices made from these fiber, than classical technology of communication optical fibers. The consequence is different fiber properties, nonstandard dimensions and different metrological problems. The price to be paid for wider design possibilities are bigger optical losses of these fibers and weaker mechanical properties, and worse chemical stability. These fibers find their applications outside the field of telecommunications. The applications of instrumentation optical fibers combine other techniques apart from the photonics ones like: electronic, chemical and mechatronic.

  11. Omnidirectional fiber optic tiltmeter

    DOEpatents

    Benjamin, B.C.; Miller, H.M.

    1983-06-30

    A tiltmeter is provided which is useful in detecting very small movements such as earth tides. The device comprises a single optical fiber, and an associated weight affixed thereto, suspended from a support to form a pendulum. A light source, e.g., a light emitting diode, mounted on the support transmits light through the optical fiber to a group of further optical fibers located adjacent to but spaced from the free end of the single optical fiber so that displacement of the single optical fiber with respect to the group will result in a change in the amount of light received by the individual optical fibers of the group. Photodetectors individually connectd to the fibers produce corresponding electrical outputs which are differentially compared and processed to produce a resultant continuous analog output representative of the amount and direction of displacement of the single optical fiber.

  12. High-performance fiber parametric oscillator for coherent Raman microscopy

    NASA Astrophysics Data System (ADS)

    Lamb, Erin S.; Lefrancois, Simon; Ji, Minbiao; Wadsworth, William J.; Xie, X. Sunney; Wise, Frank W.

    2014-02-01

    A compact, alignment-free, and inexpensive fiber source for coherent Raman spectroscopy would benefit the field considerably. We present a fiber optical parametric oscillator offering the best performance from a fiber-source to date. Pumping the oscillator with amplified pulses from a 1 μm fiber laser, we achieve widely spaced, narrowband pulses suitable for coherent anti-Stokes Raman scattering microscopy. The nearly transform limited, 2 ps signal pulses are generated through the use of normal dispersion four wave mixing in photonic crystal fiber, and can be tuned from 779-808 nm, limited by the tuning range of the seed laser. The average signal power can reach 180 mW (pulse energies up to 4 nJ). The long-wavelength idler field is resonant in the oscillator, and the use of a narrow bandpass filter in the feedback loop is critical for stable operation, as seen in both simulation and experiment. Due to the self-consistent nature of the oscillator, this source provides lower relative intensity noise on its output pulses than parametric amplifiers based on the same frequency conversion process. We present high quality images of mouse tissues taken with this source that exhibit an outstanding signal to noise ratio at top imaging speeds.

  13. Fiber optic vibration sensor

    DOEpatents

    Dooley, J.B.; Muhs, J.D.; Tobin, K.W.

    1995-01-10

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity. 2 figures.

  14. Fiber optic vibration sensor

    DOEpatents

    Dooley, Joseph B.; Muhs, Jeffrey D.; Tobin, Kenneth W.

    1995-01-01

    A fiber optic vibration sensor utilizes two single mode optical fibers supported by a housing with one optical fiber fixedly secured to the housing and providing a reference signal and the other optical fiber having a free span length subject to vibrational displacement thereof with respect to the housing and the first optical fiber for providing a signal indicative of a measurement of any perturbation of the sensor. Damping or tailoring of the sensor to be responsive to selected levels of perturbation is provided by altering the diameter of optical fibers or by immersing at least a portion of the free span length of the vibration sensing optical fiber into a liquid of a selected viscosity.

  15. Fiber optic micro accelerometer

    DOEpatents

    Swierkowski, Steve P.

    2005-07-26

    An accelerometer includes a wafer, a proof mass integrated into the wafer, at least one spring member connected to the proof mass, and an optical fiber. A Fabry-Perot cavity is formed by a partially reflective surface on the proof mass and a partially reflective surface on the end of the optical fiber. The two partially reflective surfaces are used to detect movement of the proof mass through the optical fiber, using an optical detection system.

  16. The Fiber Optic Connection.

    ERIC Educational Resources Information Center

    Reese, Susan

    2003-01-01

    Describes the fiber optics programs at the Career and Technical Center in Berlin, Pennsylvania and the Charles S. Monroe Technology Center in Loudoun County, Virginia. Discusses the involvement of the Fiber Optic Association with education, research and development, manufacturing, sales, distribution, installation, and maintenance of fiber optic…

  17. Airy beam optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Aadhi, A.; Chaitanya, N. Apurv; Jabir, M. V.; Vaity, Pravin; Singh, R. P.; Samanta, G. K.

    2016-05-01

    Airy beam, a non-diffracting waveform, has peculiar properties of self-healing and self-acceleration. Due to such unique properties, the Airy beam finds many applications including curved plasma wave-guiding, micro-particle manipulation, optically mediated particle clearing, long distance communication, and nonlinear frequency conversion. However, many of these applications including laser machining of curved structures, generation of curved plasma channels, guiding of electric discharges in a curved path, study of nonlinear propagation dynamics, and nonlinear interaction demand Airy beam with high power, energy, and wavelength tunability. Till date, none of the Airy beam sources have all these features in a single device. Here, we report a new class of coherent sources based on cubic phase modulation of a singly-resonant optical parametric oscillator (OPO), producing high-power, continuous-wave (cw), tunable radiation in 2-D Airy intensity profile existing over a length >2 m. Based on a MgO-doped periodically poled LiNbO3 crystal pumped at 1064 nm, the Airy beam OPO produces output power more than 8 W, and wavelength tunability across 1.51–1.97 μm. This demonstration gives new direction for the development of sources of arbitrary structured beams at any wavelength, power, and energy in all time scales (cw to femtosecond).

  18. Airy beam optical parametric oscillator.

    PubMed

    Aadhi, A; Chaitanya, N Apurv; Jabir, M V; Vaity, Pravin; Singh, R P; Samanta, G K

    2016-01-01

    Airy beam, a non-diffracting waveform, has peculiar properties of self-healing and self-acceleration. Due to such unique properties, the Airy beam finds many applications including curved plasma wave-guiding, micro-particle manipulation, optically mediated particle clearing, long distance communication, and nonlinear frequency conversion. However, many of these applications including laser machining of curved structures, generation of curved plasma channels, guiding of electric discharges in a curved path, study of nonlinear propagation dynamics, and nonlinear interaction demand Airy beam with high power, energy, and wavelength tunability. Till date, none of the Airy beam sources have all these features in a single device. Here, we report a new class of coherent sources based on cubic phase modulation of a singly-resonant optical parametric oscillator (OPO), producing high-power, continuous-wave (cw), tunable radiation in 2-D Airy intensity profile existing over a length >2 m. Based on a MgO-doped periodically poled LiNbO3 crystal pumped at 1064 nm, the Airy beam OPO produces output power more than 8 W, and wavelength tunability across 1.51-1.97 μm. This demonstration gives new direction for the development of sources of arbitrary structured beams at any wavelength, power, and energy in all time scales (cw to femtosecond). PMID:27143582

  19. Airy beam optical parametric oscillator

    PubMed Central

    Aadhi, A.; Chaitanya, N. Apurv; Jabir, M. V.; Vaity, Pravin; Singh, R. P.; Samanta, G. K.

    2016-01-01

    Airy beam, a non-diffracting waveform, has peculiar properties of self-healing and self-acceleration. Due to such unique properties, the Airy beam finds many applications including curved plasma wave-guiding, micro-particle manipulation, optically mediated particle clearing, long distance communication, and nonlinear frequency conversion. However, many of these applications including laser machining of curved structures, generation of curved plasma channels, guiding of electric discharges in a curved path, study of nonlinear propagation dynamics, and nonlinear interaction demand Airy beam with high power, energy, and wavelength tunability. Till date, none of the Airy beam sources have all these features in a single device. Here, we report a new class of coherent sources based on cubic phase modulation of a singly-resonant optical parametric oscillator (OPO), producing high-power, continuous-wave (cw), tunable radiation in 2-D Airy intensity profile existing over a length >2 m. Based on a MgO-doped periodically poled LiNbO3 crystal pumped at 1064 nm, the Airy beam OPO produces output power more than 8 W, and wavelength tunability across 1.51–1.97 μm. This demonstration gives new direction for the development of sources of arbitrary structured beams at any wavelength, power, and energy in all time scales (cw to femtosecond). PMID:27143582

  20. Fiber optic laser rod

    DOEpatents

    Erickson, G.F.

    1988-04-13

    A laser rod is formed from a plurality of optical fibers, each forming an individual laser. Synchronization of the individual fiber lasers is obtained by evanescent wave coupling between adjacent optical fiber cores. The fiber cores are dye-doped and spaced at a distance appropriate for evanescent wave coupling at the wavelength of the selected dye. An interstitial material having an index of refraction lower than that of the fiber core provides the optical isolation for effective lasing action while maintaining the cores at the appropriate coupling distance. 2 figs.

  1. Self-seeding ring optical parametric oscillator

    DOEpatents

    Smith, Arlee V.; Armstrong, Darrell J.

    2005-12-27

    An optical parametric oscillator apparatus utilizing self-seeding with an external nanosecond-duration pump source to generate a seed pulse resulting in increased conversion efficiency. An optical parametric oscillator with a ring configuration are combined with a pump that injection seeds the optical parametric oscillator with a nanosecond duration, mJ pulse in the reverse direction as the main pulse. A retroreflecting means outside the cavity injects the seed pulse back into the cavity in the direction of the main pulse to seed the main pulse, resulting in higher conversion efficiency.

  2. Infrared optical fibers

    NASA Astrophysics Data System (ADS)

    Drexhage, Martin G.; Moynihan, Cornelius T.

    1988-11-01

    The development of IR optical fibers for medical, laser, industrial, and telecommunications applications is discussed. IR studies of single and polycrystalline materials, chalcogenide glasses, and heavy-metal fluoride glasses are reviewed. It is suggested that heavy-metal fluoride glasses are the best prospects for obtaining optical losses lower than those in high-quality silica fibers.

  3. Multimode optical fiber

    DOEpatents

    Bigot-Astruc, Marianne; Molin, Denis; Sillard, Pierre

    2014-11-04

    A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

  4. Fiber optic temperature sensor

    NASA Technical Reports Server (NTRS)

    Morey, W. W.; Glenn, W. H.; Snitzer, E.

    1983-01-01

    A temperature sensor has been developed that utilizes the temperature dependent absorption of a rare earth doped optical fiber. The temperature measurement is localized at a remote position by splicing a short section of the rare earth fiber into a loop of commercial data communication fiber that sends and returns an optical probe signal to the temperature sensitive section of fiber. The optical probe signal is generated from two different wavelength filtered LED sources. A four port fiber optic coupler combines the two separate wavelength signals into the fiber sensing loop. Time multiplexing is used so that each signal wavelength is present at a different time. A reference signal level measurement is also made from the LED sources and a ratio taken with the sensor signal to produce a transmission measurement of the fiber loop. The transmission is affected differently at each wavelength by the rare earth temperature sensitive fiber. The temperature is determined from a ratio of the two transmission measurements. This method eliminates any ambiguity with respect to changes in signal level in the fiber loop such as mating and unmating optical connectors. The temperature range of the sensor is limited to about 800 C by the temperature limit fo the feed fibers.

  5. Fiber optic attenuator

    NASA Technical Reports Server (NTRS)

    Buzzetti, Mike F. (Inventor)

    1994-01-01

    A fiber optic attenuator of the invention is a mandrel structure through which a bundle of optical fibers is wrapped around in a complete circle. The mandrel structure includes a flexible cylindrical sheath through which the bundle passes. A set screw on the mandrel structure impacts one side of the sheath against two posts on the opposite side of the sheath. By rotating the screw, the sheath is deformed to extend partially between the two posts, bending the fiber optic bundle to a small radius controlled by rotating the set screw. Bending the fiber optic bundle to a small radius causes light in each optical fiber to be lost in the cladding, the amount depending upon the radius about which the bundle is bent.

  6. Python fiber optic seal

    SciTech Connect

    Ystesund, K.; Bartberger, J.; Brusseau, C.; Fleming, P.; Insch, K.; Tolk, K.

    1993-08-01

    Sandia National Laboratories has developed a high security fiber optic seal that incorporates tamper resistance features that are not available in commercial fiber optic seals. The Python Seal is a passive fiber optic loop seal designed to give indication of unauthorized entry. The seal includes a fingerprint feature that provides seal identity information in addition to the unique fiber optic pattern created when the seal is installed. The fiber optic cable used for the seal loop is produced with tamper resistant features that increase the difficulty of attacking that component of a seal. A Seal Reader has been developed that will record the seal signature and the fingerprint feature of the seal. A Correlator software program then compares seal images to establish a match or mismatch. SNL is also developing a Polaroid reader to permit hard copies of the seal patterns to be obtained directly from the seal.

  7. Fiber optic hydrophone

    DOEpatents

    Kuzmenko, Paul J.; Davis, Donald T.

    1994-01-01

    A miniature fiber optic hydrophone based on the principles of a Fabry-Perot interferometer. The hydrophone, in one embodiment, includes a body having a shaped flexible bladder at one end which defines a volume containing air or suitable gas, and including a membrane disposed adjacent a vent. An optic fiber extends into the body with one end terminating in spaced relation to the membrane. Acoustic waves in the water that impinge on the bladder cause the pressure of the volume therein to vary causing the membrane to deflect and modulate the reflectivity of the Fabry-Perot cavity formed by the membrane surface and the cleaved end of the optical fiber disposed adjacent to the membrane. When the light is transmitted down the optical fiber, the reflected signal is amplitude modulated by the incident acoustic wave. Another embodiment utilizes a fluid filled volume within which the fiber optic extends.

  8. Fiber optic hydrophone

    DOEpatents

    Kuzmenko, P.J.; Davis, D.T.

    1994-05-10

    A miniature fiber optic hydrophone based on the principles of a Fabry-Perot interferometer is disclosed. The hydrophone, in one embodiment, includes a body having a shaped flexible bladder at one end which defines a volume containing air or suitable gas, and including a membrane disposed adjacent a vent. An optical fiber extends into the body with one end terminating in spaced relation to the membrane. Acoustic waves in the water that impinge on the bladder cause the pressure of the volume therein to vary causing the membrane to deflect and modulate the reflectivity of the Fabry-Perot cavity formed by the membrane surface and the cleaved end of the optical fiber disposed adjacent to the membrane. When the light is transmitted down the optical fiber, the reflected signal is amplitude modulated by the incident acoustic wave. Another embodiment utilizes a fluid filled volume within which the fiber optic extends. 2 figures.

  9. Fiber optics for controls

    NASA Technical Reports Server (NTRS)

    Seng, Gary T.

    1987-01-01

    The challenge of those involved in control-system hardware development is to accommodate an ever-increasing complexity in aircraft control, while limiting the size and weight of the components and improving system reliability. A technology that displays promise towards this end is the area of fiber optics for controls. The primary advantages of employing optical fibers, passive optical sensors, and optically controlled actuators are weight and volume reduction, immunity from electromagnetic effects, superior bandwidth capabilities, and freedom from short circuits and sparking contacts. Since 1975, NASA Lewis has performed in-house, contract, and grant research in fiber optic sensors, high-temperature electro-optic switches, and fly-by-light control-system architecture. Passive optical sensor development is an essential yet challenging area of work and has therefore received much attention during this period. A major effort to develop fly-by-light control-system technology, known as the Fiber-Optic Control System Integration (FOCSI) program, was initiated in 1985 as a cooperative effort between NASA and DOD. Phase 1 of FOCSI, completed in 1986, was aimed at the design of a fiber-optic integrated propulsion/flight control system. Phase 2, yet to be initiated, will provide subcomponent and system development, and a system engine test. In addition to a summary of the benefits of fiber optics, the FOCSI program, sensor advances, and future directions in the NASA Lewis program will be discussed.

  10. Fiber optic moisture sensor

    DOEpatents

    Kirkham, R.R.

    1984-08-03

    A method and apparatus for sensing moisture changes by utilizing optical fiber technology. One embodiment uses a reflective target at the end of an optical fiber. The reflectance of the target varies with its moisture content and can be detected by a remote unit at the opposite end of the fiber. A second embodiment utilizes changes in light loss along the fiber length. This can be attributed to changes in reflectance of cladding material as a function of its moisture content. It can also be affected by holes or inserts interposed in the cladding material and/or fiber. Changing light levels can also be coupled from one fiber to another in an assembly of fibers as a function of varying moisture content in their overlapping lengths of cladding material.

  11. Fiber optic choline biosensor

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Cao, Xiaojian; Jia, Ke; Chai, Xueting; Lu, Hua; Lu, Zuhong

    2001-10-01

    A fiber optic fluorescence biosensor for choline is introduced in this paper. Choline is an important neurotransmitter in mammals. Due to the growing needs for on-site clinical monitoring of the choline, much effect has been devoted to develop choline biosensors. Fiber-optic fluorescence biosensors have many advantages, including miniaturization, flexibility, and lack of electrical contact and interference. The choline fiber-optic biosensor we designed implemented a bifurcated fiber to perform fluorescence measurements. The light of the blue LED is coupled into one end of the fiber as excitation and the emission spectrum from sensing film is monitored by fiber-spectrometer (S2000, Ocean Optics) through the other end of the fiber. The sensing end of the fiber is coated with Nafion film dispersed with choline oxidase and oxygen sensitive luminescent Ru(II) complex (Tris(2,2'-bipyridyl)dichlororuthenium(II), hexahydrate). Choline oxidase catalyzes the oxidation of choline to betaine and hydrogen peroxide while consuming oxygen. The fluorescence intensity of oxygen- sensitive Ru(II) are related to the choline concentration. The response of the fiber-optic sensor in choline solution is represented and discussed. The result indicates a low-cost, high-performance, portable choline biosensor.

  12. Infrared fiber optic materials

    NASA Technical Reports Server (NTRS)

    Feigelson, Robert S.

    1987-01-01

    The development of IR fiber optics for use in astronomical and other space applications is summarized. Candidate materials were sought for use in the 1 to 200 micron and the 200 to 1000 micron wavelength range. Synthesis and optical characterization were carried out on several of these materials in bulk form. And the fabrication of a few materials in single crystal fiber optic form were studied.

  13. Fiber optic communication links

    SciTech Connect

    Meyer, R. H.

    1980-01-01

    Fiber optics is a new, emerging technology which offers relief from many of the problems which limited past communications links. Its inherent noise immunity and high bandwidth open the door for new designs with greater capabilities. Being a new technology, certain problems can be encountered in specifying and installing a fiber optic link. A general fiber optic system is discussed with emphasis on the advantages and disadvantages. It is not intended to be technical in nature, but a general discussion. Finally, a general purpose prototype Sandia communications link is presented.

  14. Generation of 1.024-Tb/s Nyquist-WDM phase-conjugated twin vector waves by a polarization-insensitive optical parametric amplifier for fiber-nonlinearity-tolerant transmission.

    PubMed

    Liu, Xiang; Hu, Hao; Chandrasekhar, S; Jopson, R M; Gnauck, A H; Dinu, M; Xie, C; Winzer, P J

    2014-03-24

    We experimentally demonstrate the generation of 1.024-Tb/s Nyquist-WDM phase-conjugated vector twin waves (PCTWs), consisting of eight 128-Gb/s polarization-division-multiplexed QPSK signals and their idlers, by a broadband polarization-insensitive fiber optic parametric amplifier. This novel all-optical signal processing approach to generate WDM-PCTWs enables a 2-fold reduction in the needed optical transmitters as compared to the conventional approach where each idler is generated by a dedicated transmitter. Digital coherent superposition of the twin waves at the receiver enables more than doubled reach in a dispersion-managed transmission link. We further study the impact of polarization-mode dispersion on the performance gain brought by the phase-conjugated twin waves, showing a gain of ~3.8 dB in signal quality factors. PMID:24663996

  15. Splicing Efficiently Couples Optical Fibers

    NASA Technical Reports Server (NTRS)

    Lutes, G. F.

    1985-01-01

    Method of splicing single-mode optical fibers results in very low transmission losses through joined fiber ends. Coupling losses between joined optical-fiber ends only 0.1 dB. Method needs no special operator training.

  16. Fiber Optics: No Illusion.

    ERIC Educational Resources Information Center

    American School and University, 1983

    1983-01-01

    A campus computer center at Hofstra University (New York) that holds 70 terminals for student use was first a gymnasium, then a language laboratory. Strands of fiber optics are used for the necessary wiring. (MLF)

  17. Fiber optic data transmission

    NASA Technical Reports Server (NTRS)

    Shreve, Steven T.

    1987-01-01

    The Ohio University Avionics Engineering Center is currently developing a fiber optic data bus transmission and reception system that could eventually replace copper cable connections in airplanes. The original form of the system will transmit information from an encoder to a transponder via a fiber optic cable. An altimeter and an altitude display are connected to a fiber optic transmitter by copper cable. The transmitter converts the altimetry data from nine bit parallel to serial form and send these data through a fiber optic cable to a receiver. The receiver converts the data using a cable similar to that used between the altimeter and display. The transmitting and receiving ends also include a display readout. After completion and ground testing of the data bus, the system will be tested in an airborne environment.

  18. Simulating Optical Fibers.

    ERIC Educational Resources Information Center

    Edgar, Dale

    1988-01-01

    Described is a demonstration of Snell's law using a laser beam and an optical fiber. Provided are the set-up method of the demonstration apparatus and some practical suggestions including "index matching" technique using vaseline. (YP)

  19. Fiber optic hydrogen sensor

    DOEpatents

    Buchanan, B.R.; Prather, W.S.

    1991-01-01

    Apparatus and method for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading, by a single spectrophotometer.

  20. Fiber optic hydrogen sensor

    DOEpatents

    Buchanan, B.R.; Prather, W.S.

    1992-10-06

    An apparatus and method are described for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading by a single spectrophotometer. 4 figs.

  1. Fiber optic hydrogen sensor

    DOEpatents

    Buchanan, Bruce R.; Prather, William S.

    1992-01-01

    An apparatus and method for detecting a chemical substance by exposing an optic fiber having a core and a cladding to the chemical substance so that the chemical substance can be adsorbed onto the surface of the cladding. The optic fiber is coiled inside a container having a pair of valves for controlling the entrance and exit of the substance. Light from a light source is received by one end of the optic fiber, preferably external to the container, and carried by the core of the fiber. Adsorbed substance changes the transmissivity of the fiber as measured by a spectrophotometer at the other end, also preferably external to the container. Hydrogen is detected by the absorption of infrared light carried by an optic fiber with a silica cladding. Since the adsorption is reversible, a sensor according to the present invention can be used repeatedly. Multiple positions in a process system can be monitored using a single container that can be connected to each location to be monitored so that a sample can be obtained for measurement, or, alternatively, containers can be placed near each position and the optic fibers carrying the partially-absorbed light can be multiplexed for rapid sequential reading by a single spectrophotometer.

  2. Fiber optic detector

    SciTech Connect

    Partin, J.K.; Ward, T.E.; Grey, A.E.

    1990-12-31

    This invention is comprised of a portable fiber optic detector that senses the presence of specific target chemicals by exchanging the target chemical for a fluorescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

  3. Fiber optic detector

    NASA Astrophysics Data System (ADS)

    Partin, Judy K.; Ward, Thomas E.; Grey, Alan E.

    1990-04-01

    This invention is comprised of a portable fiber optic detector that senses the presence of specific target chemicals by exchanging the target chemical for a fluorescently-tagged antigen that is bound to an antibody which is in turn attached to an optical fiber. Replacing the fluorescently-tagged antigen reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

  4. Fiber optics welder

    DOEpatents

    Higgins, R.W.; Robichaud, R.E.

    A system is described for welding fiber optic waveguides together. The ends of the two fibers to be joined together are accurately, collinearly aligned in a vertical orientation and subjected to a controlled, diffuse arc to effect welding and thermal conditioning. A front-surfaced mirror mounted at a 45/sup 0/ angle to the optical axis of a stereomicroscope mounted for viewing the junction of the ends provides two orthogonal views of the interface during the alignment operation.

  5. Fiber optics: A research paper

    NASA Technical Reports Server (NTRS)

    Drone, Melinda M.

    1987-01-01

    Some basic aspects concerning fiber optics are examined. Some history leading up to the development of optical fibers which are now used in the transmission of data in many areas of the world is discussed. Basic theory of the operation of fiber optics is discussed along with methods for improving performance of the optical fiber through much research and design. Splices and connectors are compared and short haul and long haul fiber optic networks are discussed. Fiber optics plays many roles in the commercial world. The use of fiber optics for communication applications is emphasized.

  6. Self Similar Optical Fiber

    NASA Astrophysics Data System (ADS)

    Lai, Zheng-Xuan

    This research proposes Self Similar optical fiber (SSF) as a new type of optical fiber. It has a special core that consists of self similar structure. Such a structure is obtained by following the formula for generating iterated function systems (IFS) in Fractal Theory. The resulted SSF can be viewed as a true fractal object in optical fibers. In addition, the method of fabricating SSF makes it possible to generate desired structures exponentially in numbers, whereas it also allows lower scale units in the structure to be reduced in size exponentially. The invention of SSF is expected to greatly ease the production of optical fiber when a large number of small hollow structures are needed in the core of the optical fiber. This dissertation will analyze the core structure of SSF based on fractal theory. Possible properties from the structural characteristics and the corresponding applications are explained. Four SSF samples were obtained through actual fabrication in a laboratory environment. Different from traditional conductive heating fabrication system, I used an in-house designed furnace that incorporated a radiation heating method, and was equipped with automated temperature control system. The obtained samples were examined through spectrum tests. Results from the tests showed that SSF does have the optical property of delivering light in a certain wavelength range. However, SSF as a new type of optical fiber requires a systematic research to find out the theory that explains its structure and the associated optical properties. The fabrication and quality of SSF also needs to be improved for product deployment. As a start of this extensive research, this dissertation work opens the door to a very promising new area in optical fiber research.

  7. Fiber optic hydrogen sensor

    NASA Astrophysics Data System (ADS)

    Jung, Chuck C.; Saaski, Elric W.; McCrae, David A.

    1998-09-01

    This paper describes a novel fiber optic-based hydrogen sensor. The sensor consists of a thin-film etalon, constructed on the distal end of a fiber optic. The exterior mirror of the etalon is palladium or a palladium-alloy, which undergoes an optical change upon exposure to hydrogen. Data is presented on fiber optic sensors constructed with palladium and several alloys of palladium. The linearity of the optical response of these sensors to hydrogen is examined. Etalons made with pure palladium are found to be desirable for sensing low concentrations of hydrogen, or for one-time exposure to high concentrations of hydrogen. Etalons made from palladium alloys are found to be more desirable in applications were repeated cycling in high concentrations of hydrogen occurs.

  8. Compact, passively Q-switched, all-solid-state master oscillator-power amplifier-optical parametric oscillator (MOPA-OPO) system pumped by a fiber-coupled diode laser generating high-brightness, tunable, ultraviolet radiation.

    PubMed

    Peuser, Peter; Platz, Willi; Fix, Andreas; Ehret, Gerhard; Meister, Alexander; Haag, Matthias; Zolichowski, Paul

    2009-07-01

    We report on a compact, tunable ultraviolet laser system that consists of an optical parametric oscillator (OPO) and a longitudinally diode-pumped Nd:YAG master oscillator-power amplifier (MOPA). The pump energy for the whole laser system is supplied via a single delivery fiber. Nanosecond pulses are produced by an oscillator that is passively Q-switched by a Cr(4+):YAG crystal. The OPO is pumped by the second harmonic of the Nd:YAG MOPA. Continuously tunable radiation is generated by an intracavity sum-frequency mixing process within the OPO in the range of 245-260 nm with high beam quality. Maximum pulse energies of 1.2 mJ were achieved, which correspond to an optical efficiency of 3.75%, relating to the pulse energy of the MOPA at 1064 nm. PMID:19571944

  9. Fiber optic accelerometer

    NASA Technical Reports Server (NTRS)

    August, Rudolf R. (Inventor); Strahan, Virgil H. (Inventor); James, Kenneth A. (Inventor); Nichols, Donald K. (Inventor)

    1980-01-01

    An inexpensive, light weight fiber optic accelerometer to convert input mechanical motion (e.g. acceleration) into digitized optical output signals. The output of the accelerometer may be connected directly to data processing apparatus without the necessity of space consuming analog to digital interface means.

  10. Fiber optic accelerometer

    NASA Technical Reports Server (NTRS)

    Strahan, Virgil H. (Inventor); James, Kenneth A. (Inventor); Quick, William H. (Inventor)

    1983-01-01

    An inexpensive, light weight fiber optic accelerometer to convert input mechanical motion (e.g. acceleration) into digitized optical output signals. The output of the accelerometer may be connected directly to data processing apparatus without the necessity of space consuming analog to digital interface means.

  11. Fiber optics for controls

    NASA Technical Reports Server (NTRS)

    Seng, Gary T.

    1990-01-01

    The design, development, and testing of a fiber optic integrated propulsion/flight control system for an advanced supersonic dash aircraft (flies at supersonic speeds for short periods of time) is the goal of the joint NASA/DOD Fiber Optic Control System Integration (FOCSI) program. Phase 1 provided a comparison of electronic and optical control systems, identified the status of current optical sensor technology, defined the aircraft sensor/actuator environment, proposed architectures for fully optical control systems, and provided schedules for development. Overall, it was determined that there are sufficient continued efforts to develop such a system. It was also determined that it is feasible to build a fiber optic control system for the development of a data base for this technology, but that further work is necessary in sensors, actuators, and components to develop an optimum design, fully fiber optic integrated control system compatible with advanced aircraft environments. Phase 2 is to design, construct, and ground test a fly by light control system. Its first task is to provide a detailed design of the electro-optic architecture.

  12. Fiber optic interferometric accelerometers

    SciTech Connect

    Vohra, S.T.; Danver, B.; Tveten, A.; Dandridge, A.

    1996-04-01

    Recent progress on the development of flexural disk based fiber optic acceleration sensors is reported. Appropriate geometric considerations have resulted in fiber optic accelerometers with many desirable features including (i) high sensitivity ({approx_gt}20 dB rerad/g), (ii) flat frequency response (200 Hz to {approx_gt}10 kHz), and (iii) low pressure ({lt}{minus}180 dB rerad/{mu}Pa) and transverse sensitivity ({lt}{minus}30 dB). Alternate transducer designs are discussed and preliminary results reported. Various optical multiplexing schemes for accelerometer arrays are discussed. {copyright} {ital 1996 American Institute of Physics.}

  13. Silicon fiber optic sensors

    DOEpatents

    Pocha, Michael D.; Swierkowski, Steve P.; Wood, Billy E.

    2007-10-02

    A Fabry-Perot cavity is formed by a partially or wholly reflective surface on the free end of an integrated elongate channel or an integrated bounding wall of a chip of a wafer and a partially reflective surface on the end of the optical fiber. Such a constructed device can be utilized to detect one or more physical parameters, such as, for example, strain, through the optical fiber using an optical detection system to provide measuring accuracies of less than aboutb0.1%.

  14. Optical fiber laser

    SciTech Connect

    Snitzer, E.

    1988-10-25

    This patent describes an optical fiber laser comprising: a gain cavity including a single mode optical fiber of given length and index of refraction and a cladding surrounding the core and having an index of refraction lower than that of the core. The core comprising a host material having incorporated therein a predetermined concentration of just erbium oxide having a fluorescence spectrum with a peak emission line at 1.54 micrometers; filter means optically coupled to each end of the fiber gain cavity for providing feedback in the cavity at the peak emission line of the erbium oxide and for permitting energy to be introduced into the cavity at the absorption band of the erbium oxide in the region of 1.45 to 1.53 micrometers; and a laser diode optically coupled to one end of the core for pumping energy into the end of the gain cavity so that the gain cavity oscillates at just the peak emission line.

  15. Optical fiber switch

    DOEpatents

    Early, James W.; Lester, Charles S.

    2002-01-01

    Optical fiber switches operated by electrical activation of at least one laser light modulator through which laser light is directed into at least one polarizer are used for the sequential transport of laser light from a single laser into a plurality of optical fibers. In one embodiment of the invention, laser light from a single excitation laser is sequentially transported to a plurality of optical fibers which in turn transport the laser light to separate individual remotely located laser fuel ignitors. The invention can be operated electro-optically with no need for any mechanical or moving parts, or, alternatively, can be operated electro-mechanically. The invention can be used to switch either pulsed or continuous wave laser light.

  16. Electrospun Amplified Fiber Optics

    PubMed Central

    2015-01-01

    All-optical signal processing is the focus of much research aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for efficient signal transmission. However, the complex fabrication methods involving high-temperature processes performed in a highly pure environment slow the fabrication process and make amplified components expensive with respect to an ideal, high-throughput, room temperature production. Here, we report on near-infrared polymer fiber amplifiers working over a band of ∼20 nm. The fibers are cheap, spun with a process entirely carried out at room temperature, and shown to have amplified spontaneous emission with good gain coefficients and low levels of optical losses (a few cm–1). The amplification process is favored by high fiber quality and low self-absorption. The found performance metrics appear to be suitable for short-distance operations, and the large variety of commercially available doping dyes might allow for effective multiwavelength operations by electrospun amplified fiber optics. PMID:25710188

  17. Wavelength-doubling optical parametric oscillator

    DOEpatents

    Armstrong, Darrell J.; Smith, Arlee V.

    2007-07-24

    A wavelength-doubling optical parametric oscillator (OPO) comprising a type II nonlinear optical medium for generating a pair of degenerate waves at twice a pump wavelength and a plurality of mirrors for rotating the polarization of one wave by 90 degrees to produce a wavelength-doubled beam with an increased output energy by coupling both of the degenerate waves out of the OPO cavity through the same output coupler following polarization rotation of one of the degenerate waves.

  18. The Quantum Theory of Optical Parametric Amplification

    NASA Astrophysics Data System (ADS)

    Hussain, N. A.

    Available from UMI in association with The British Library. Requires signed TDF. The aim of this thesis is to investigate the effect of parametric amplification on various forms of light. In particular we shall consider number and coherent states, but many of the calculations hold for those states whose operators satisfy the properties, < {a}^+{a}^+ >=<{a}{a }> = < {a}^+>=<{a }>=0 e.g. chaotic light. The first chapter lays down the fundamental preliminaries necessary for our calculations and reviews linear amplifier theory. We consider the phase sensitive and insensitive forms of amplifiers modelling the former on the degenerate parametric amplifier and the latter on the non-degenerate and inverted population amplifiers. Chapter 2 deals with balanced homodyne detection of a narrow band coherent state before and after degenerate parametric amplification. In chapter 3 we consider a continuous mode number state produced by atomic emission and parametrically amplified using the formalism of Collett and Gardiner. We give general results for the output flux intensity and also consider the simpler case where the atomic decay rate is much smaller than the parametric cavity decay rate. Also we consider the degree of second order coherence using this simplified theory. Chapters 4 and 5 consider the double amplifier interferometer, using single and continuous mode theories, and enable us to determine the form of amplifier which produces the best visibility and hence lowest noise figures. The travelling-wave parametric amplifier is discussed in chapter 6 and is contrasted with the cavity parametric amplifier discussed in chapters 1 and 2. Finally we consider the much contemplated idea of using amplifiers to boost signals in fibre optic transmission lines using our model of the parametric amplifier and examining the degradation of the signal-to-noise ratio. We consider both coherent and squeezed inputs and our results hold for both cavity and travelling -wave amplifiers.

  19. Optical fiber stripper positioning apparatus

    DOEpatents

    Fyfe, Richard W.; Sanchez, Jr., Amadeo

    1990-01-01

    An optical fiber positioning apparatus for an optical fiber stripping device is disclosed which is capable of providing precise axial alignment between an optical fiber to be stripped of its outer jacket and the cutting blades of a stripping device. The apparatus includes a first bore having a width approximately equal to the diameter of an unstripped optical fiber and a counter bore axially aligned with the first bore and dimensioned to precisely receive a portion of the stripping device in axial alignment with notched cutting blades within the stripping device to thereby axially align the notched cutting blades of the stripping device with the axis of the optical fiber to permit the notched cutting blades to sever the jacket on the optical fiber without damaging the cladding on the optical fiber. In a preferred embodiment, the apparatus further includes a fiber stop which permits determination of the length of jacket to be removed from the optical fiber.

  20. Fiber Optic Calorimetry

    SciTech Connect

    Rudy, C.; Bayliss, S.; Bracken, D.; Bush, J.; Davis, P.

    1997-12-12

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using optical fibers for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processes to allow phase shifts as small as 1 microradian ({micro}rad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% {sup 240}Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium.

  1. Diode-pumped optical parametric oscillator

    SciTech Connect

    Geiger, A.R.; Hemmati, H.; Farr, W.H.

    1996-02-01

    Diode-pumped optical parametric oscillation has been demonstrated for the first time to our knowledge in a single Nd:MgO:LiNbO{sub 3} nonlinear crystal. The crystal is pumped by a semiconductor diode laser array at 812 nm. The Nd{sup 3+} ions absorb the 812-nm radiation to generate 1084-nm laser oscillation. On internal {ital Q} switching the 1084-nm radiation pumps the LiNbO{sub 3} host crystal that is angle cut at 46.5{degree} and generates optical parametric oscillation. The oscillation threshold that is due to the 1084-nm laser pump with a pulse length of 80 ns in a 1-mm-diameter beam was measured to be {approx_equal}1 mJ and produced 0.5-mJ output at 3400-nm signal wavelength. {copyright} {ital 1996 Optical Society of America.}

  2. Electro-optically spectrum tailorable intracavity optical parametric oscillator.

    PubMed

    Chung, H P; Chang, W K; Tseng, C H; Geiss, R; Pertsch, T; Chen, Y H

    2015-11-15

    We report a unique, pulsed intracavity optical parametric oscillator (IOPO) whose output spectrum is electro-optically (EO) tailorable based on an aperiodically poled lithium niobate (APPLN) working simultaneously as an optical parametric gain medium and an active gain spectrum filter in the system. We have successfully obtained from the IOPO the emission of single to multiple narrow-line signal spectral peaks in a near-infrared (1531 nm) band simply by electro-optic control. The power spectral density of the EO tailored signal can be enhanced by up to 10 times over the original (nontailored) signal. PMID:26565817

  3. Hermetically coated specialty optical fibers

    NASA Astrophysics Data System (ADS)

    Semjonov, Sergey L.; Bogatyrev, Vladimir A.; Malinin, Alexei A.

    2010-10-01

    Manufacturing processes for different types of hermetically coated fibers are described. Optical and mechanical properties of metal and carbon coated fibers are compared. Prospects of application of both types of hermetically coated fibers in special applications are discussed.

  4. Integrated optics for fiber optic sensors

    NASA Technical Reports Server (NTRS)

    Minford, W. J.; Depaula, R. P.

    1991-01-01

    Recent progress achieved in the field of fiber-optic sensor applications is discussed with emphasis placed on LiNbO3-based integrated optics (IO). Particular consideration is given to advanced electromagnetic-field sensors, an integrated laser vibrometer system, and a fiber-optic gyroscope system. It is shown that the multifunction IO chips have enabled high perforamance fiber-optic sensors (e.g., fiber-optic gyros), provided advanced and unique signal processing capabilities and advanced architectures, and have a potential of making fiber-optic sensors at low cost.

  5. Fiber optic fluid detector

    DOEpatents

    Angel, S.M.

    1987-02-27

    Particular gases or liquids are detected with a fiber optic element having a cladding or coating of a material which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses. 10 figs.

  6. Fiber optic fluid detector

    DOEpatents

    Angel, S. Michael

    1989-01-01

    Particular gases or liquids are detected with a fiber optic element (11, 11a to 11j) having a cladding or coating of a material (23, 23a to 23j) which absorbs the fluid or fluids and which exhibits a change of an optical property, such as index of refraction, light transmissiveness or fluoresence emission, for example, in response to absorption of the fluid. The fluid is sensed by directing light into the fiber optic element and detecting changes in the light, such as exit angle changes for example, that result from the changed optical property of the coating material. The fluid detector (24, 24a to 24j) may be used for such purposes as sensing toxic or explosive gases in the atmosphere, measuring ground water contamination or monitoring fluid flows in industrial processes, among other uses.

  7. Enhanced radiation resistant fiber optics

    DOEpatents

    Lyons, P.B.; Looney, L.D.

    1993-11-30

    A process for producing an optical fiber having enhanced radiation resistance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation. 4 figures.

  8. Enhanced radiation resistant fiber optics

    DOEpatents

    Lyons, Peter B.; Looney, Larry D.

    1993-01-01

    A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.

  9. Chiral fiber optical isolator

    NASA Astrophysics Data System (ADS)

    Kopp, Victor I.; Zhang, Guoyin; Zhang, Sheng; Genack, Azriel Z.; Neugroschl, Dan

    2009-02-01

    We propose an in-fiber chiral optical isolator based on chiral fiber polarizer technology and calculate its performance by incorporating the magnetic field into the scattering matrix. The design will be implemented in a special preform, which is passed through a miniature heat zone as it is drawn and twisted. The birefringence of the fiber is controlled by adjusted the diameter of a dual-core optical fiber. By adjusting the twist, the fiber can convert linear to circular polarization and reject one component of circular polarization. In the novel central portion of the isolator, the fiber diameter is large. The effective birefringence of the circular central core with high Verdet constant embedded in an outer core of slightly smaller index of refraction is small. The central potion is a non-reciprocal polarization converter which passes forward traveling left circularly polarized (LCP) light as LCP, while converting backward propagating LCP to right circularly polarized (RCP) light. Both polarizations of light traveling backwards are scattered out of the isolator. Since it is an all-glass structure, we anticipate that the isolator will be able to handle several watts of power and will be environmentally robust.

  10. Fiber-Optic Sensing Technology

    SciTech Connect

    Milnes, M.; Baylor, L.C.; Bave, S.

    1996-10-24

    This article offers a basic review of fiber-optic sensing technology, or more specifically, fiber-optic sensing technology as applied to the qualitative or quantitative identification of a chemical sample, and how it works,

  11. Fiber optic calorimetry

    SciTech Connect

    Rudy, C.; Bayliss, S.; Bracken, D.; Bush, J.; Davis, P.

    1998-01-01

    A twin-bridge calorimeter using optical fiber as the sensor element was constructed and tested. This system demonstrates the principle and capability of using fiber for heat-flow measurements of special nuclear material. This calorimeter uses piezoelectric-generated phase-carrier modulation with subsequent electronic signal processing to allow phase shifts as small as 1 microradian ({mu}rad) to be measured. The sensing element consists of 21-m lengths of single-mode optical fiber wrapped around sample and reference chambers. The sensitivity of the calorimeter was determined to be 74 radians (rad) of phase shift per milliwatt of thermal power. One milliwatt of thermal power is equivalent to 400 mg of plutonium (6% {sup 240}Pu). The system noise base was about 0.2 rad, equivalent to about 1 mg of plutonium.

  12. Infrared Fiber Optic Sensors

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Successive years of Small Business Innovation Research (SBIR) contracts from Langley Research Center to Sensiv Inc., a joint venture between Foster-Miller Inc. and Isorad, Ltd., assisted in the creation of remote fiber optic sensing systems. NASA's SBIR interest in infrared, fiber optic sensor technology was geared to monitoring the curing cycles of advanced composite materials. These funds helped in the fabrication of an infrared, fiber optic sensor to track the molecular vibrational characteristics of a composite part while it is being cured. Foster-Miller ingenuity allowed infrared transmitting optical fibers to combine with Fourier Transform Infrared spectroscopy to enable remote sensing. Sensiv probes operate in the mid-infrared range of the spectrum, although modifications to the instrument also permits its use in the near-infrared region. The Sensiv needle-probe is built to be placed in a liquid or powder and analyze the chemicals in the mixture. Other applications of the probe system include food processing control; combustion control in furnaces; and maintenance problem solving.

  13. Optical Fiber Protection

    NASA Technical Reports Server (NTRS)

    1999-01-01

    F&S Inc. developed and commercialized fiber optic and microelectromechanical systems- (MEMS) based instrumentation for harsh environments encountered in the aerospace industry. The NASA SBIR programs have provided F&S the funds and the technology to develop ruggedized coatings and coating techniques that are applied during the optical fiber draw process. The F&S optical fiber fabrication facility and developed coating methods enable F&S to manufacture specialty optical fiber with custom designed refractive index profiles and protective or active coatings. F&S has demonstrated sputtered coatings using metals and ceramics and combinations of each, and has also developed techniques to apply thin coatings of specialized polyimides formulated at NASA Langley Research Center. With these capabilities, F&S has produced cost-effective, reliable instrumentation and sensors capable of withstanding temperatures up to 800? C and continues building commercial sales with corporate partners and private funding. More recently, F&S has adapted the same sensing platforms to provide the rapid detection and identification of chemical and biological agents

  14. Few-Cycle and Cavity-Enhanced Optical Parametric Amplification

    NASA Astrophysics Data System (ADS)

    Siddiqui, Aleem Mohammad

    Optical parametric amplifiers have emerged as important optical sources by extending the properties of few-cycle laser sources, which exist only in materials with sufficiently large gain bandwidths, to wide array of spectral ranges. The work reported in this thesis relates to two areas for the continued development of optical parametric amplification based sources. First, we present a white light seeded, carrier-envelope stable, degenerately pumped OPA producing near tranform-limited sub 7 fs, 3 microJ pulses at the driver wavelength from a long pulse, non-CEP stable Ti:sapphire regenerative amplifier. Problems to the spectral phase jump at the driver wavelength, 800 nm, were avoided by using a near infrared OPA to produce white light continuum down to 800 nm where the spectral phase is smooth. Secondly, enhancement cavities are used in conjunction with parametric amplifiers resulting in a new technique entitled, cavity-enhanced optical parametric chirped-pulse amplification (C-OPCPA). C-OPCPA increases the capabilities of nonlinear crystals and can allow continued scaling of parametric amplifier systems to high repetition rate. This work contains the first theoretical and experimental investigation of C-OPCPA. Numerically, passive pump pulse shaping of the intracavity pump power is shown to enable octave spanning gain. Experimentally, a first proof-of-principle experiment demonstrates a 78 MHz C-OPCPA with more than 50% conversion with under 1 W of incident pump power. A comparison to a single pass system shows improvements in the C-OPCPA of orders of magnitude in conversion efficiency and 3 fold increase in phase matching bandwidth in 10 and 20 mm periodically poled lithium niobate phase matched for parametric amplification with 1030 nm pump wavelength and a 1550 nm signal wavelength. A Yb-fiber laser based CPA system producing up to 5 W of 500 fs pulses comprises the pump source, and a Er-fiber laser the signal. (Copies available exclusively from MIT Libraries

  15. Improved Optical Fiber Chemical Sensors

    NASA Technical Reports Server (NTRS)

    Egalon, Claudio O.; Rogowski, Robert S.

    1994-01-01

    Calculations, based on exact theory of optical fiber, have shown how to increase optical efficiency sensitivity of active-core, step-index-profile optical-fiber fluorosensor. Calculations result of efforts to improve efficiency of optical-fiber chemical sensor of previous concept described in "Making Optical-Fiber Chemical Sensors More Sensitive" (LAR-14525). Optical fiber chemical detector of enhanced sensitivity made in several configurations. Portion of fluorescence or chemiluminescence generated in core, and launched directly into bound electromagnetic modes that propagate along core to photodetector.

  16. Nondegenerate optical parametric chirped pulse amplifier

    DOEpatents

    Jovanovic, Igor; Ebbers, Christopher A.

    2005-03-22

    A system provides an input pump pulse and a signal pulse. A first dichroic beamsplitter is highly reflective for the input signal pulse and highly transmissive for the input pump pulse. A first optical parametric amplifier nonlinear crystal transfers part of the energy from the input pump pulse to the input signal pulse resulting in a first amplified signal pulse and a first depleted pump pulse. A second dichroic beamsplitter is highly reflective for the first amplified signal pulse and highly transmissive for the first depleted pump pulse. A second optical parametric amplifier nonlinear crystal transfers part of the energy from the first depleted pump pulse to the first amplified signal pulse resulting in a second amplified signal pulse and a second depleted pump pulse. A third dichroic beamsplitter receives the second amplified signal pulse and the second depleted pump pulse. The second depleted pump pulse is discarded.

  17. Fiber Optics and Library Technology.

    ERIC Educational Resources Information Center

    Koenig, Michael

    1984-01-01

    This article examines fiber optic technology, explains some of the key terminology, and speculates about the way fiber optics will change our world. Applications of fiber optics to library systems in three major areas--linkage of a number of mainframe computers, local area networks, and main trunk communications--are highlighted. (EJS)

  18. Large core fiber optic cleaver

    DOEpatents

    Halpin, John M.

    1996-01-01

    The present invention relates to a device and method for cleaving optical fibers which yields cleaved optical fiber ends possessing high damage threshold surfaces. The device can be used to cleave optical fibers with core diameters greater than 400 .mu.m.

  19. Aerogel-clad optical fiber

    DOEpatents

    Sprehn, Gregory A.; Hrubesh, Lawrence W.; Poco, John F.; Sandler, Pamela H.

    1997-01-01

    An optical fiber is surrounded by an aerogel cladding. For a low density aerogel, the index of refraction of the aerogel is close to that of air, which provides a high numerical aperture to the optical fiber. Due to the high numerical aperture, the aerogel clad optical fiber has improved light collection efficiency.

  20. Aerogel-clad optical fiber

    DOEpatents

    Sprehn, G.A.; Hrubesh, L.W.; Poco, J.F.; Sandler, P.H.

    1997-11-04

    An optical fiber is surrounded by an aerogel cladding. For a low density aerogel, the index of refraction of the aerogel is close to that of air, which provides a high numerical aperture to the optical fiber. Due to the high numerical aperture, the aerogel clad optical fiber has improved light collection efficiency. 4 figs.

  1. Buying Fiber-Optic Networks.

    ERIC Educational Resources Information Center

    Fickes, Michael

    2003-01-01

    Describes consortia formed by college and university administrators to buy, manage, and maintain their own fiber-optic networks with the goals of cutting costs of leasing fiber-optic cable and planning for the future. Growth capacity is the real advantage of owning fiber-optic systems. (SLD)

  2. Injection-seeded optical parametric oscillator and system

    DOEpatents

    Lucht, Robert P.; Kulatilaka, Waruna D.; Anderson, Thomas N.; Bougher, Thomas L.

    2007-10-09

    Optical parametric oscillators (OPO) and systems are provided. The OPO has a non-linear optical material located between two optical elements where the product of the reflection coefficients of the optical elements are higher at the output wavelength than at either the pump or idler wavelength. The OPO output may be amplified using an additional optical parametric amplifier (OPA) stage.

  3. Entanglement of Coupled Optomechanical Systems Improved by Optical Parametric Amplifiers

    NASA Astrophysics Data System (ADS)

    Pan, Guixia; Xiao, Ruijie; Zhou, Ling

    2016-04-01

    A scheme to generate the stationary entanglement of two distant coupled optical cavities placed optical parametric amplifiers is proposed. We study how the optical parametric amplifiers can affect the entanglement behaviors of the movable mirrors and the cavity fields. With the existence of optical parametric amplifiers, we show that larger stationary entanglement of optical and mechanical modes can be obtained and the entanglement increases with the increasing parametric gain. Especially, the degree of entanglement between the two cavity fields is more pronouncedly enhanced. Moreover, for a fixed parametric gain, the entanglement of distant cavity optomechanical systems increases as the input laser power is increased.

  4. Entanglement of Coupled Optomechanical Systems Improved by Optical Parametric Amplifiers

    NASA Astrophysics Data System (ADS)

    Pan, Guixia; Xiao, Ruijie; Zhou, Ling

    2016-08-01

    A scheme to generate the stationary entanglement of two distant coupled optical cavities placed optical parametric amplifiers is proposed. We study how the optical parametric amplifiers can affect the entanglement behaviors of the movable mirrors and the cavity fields. With the existence of optical parametric amplifiers, we show that larger stationary entanglement of optical and mechanical modes can be obtained and the entanglement increases with the increasing parametric gain. Especially, the degree of entanglement between the two cavity fields is more pronouncedly enhanced. Moreover, for a fixed parametric gain, the entanglement of distant cavity optomechanical systems increases as the input laser power is increased.

  5. Parametric Study Of A Ceramic-Fiber/Metal-Matrix Composite

    NASA Technical Reports Server (NTRS)

    Murthy, P. L. N.; Hopkins, D. A.; Chamis, C. C.

    1992-01-01

    Report describes computer-model parametric study of effects of degradation of constituent materials upon mechanical properties of ceramic-fiber/metal-matrix composite material. Contributes to understanding of weakening effects of large changes in temperature and mechanical stresses in fabrication and use. Concerned mainly with influences of in situ fiber and matrix properties upon behavior of composite. Particular attention given to influence of in situ matrix strength and influence of interphase degradation.

  6. Fiber optics: A brief introduction

    SciTech Connect

    Gruchalla, M.E.

    1989-01-01

    A basic introduction into the principles of fiber optics is presented. A review of both the underlying physical principles and the individual elements of typical fiber-optic systems are presented. The optical phenomenon of total internal reflection is reviewed. The basic construction of the optical fiber is presented. Both step-index and graded-index fiber designs are reviewed. Multimode and single-mode fiber constructions are considered and typical performance parameters given. Typical optical-fiber bandwidth and loss characteristics are compared to various common coaxial cables, waveguides, and air transmission. The constructions of optical-fiber cables are reviewed. Both loose-tube and tightly-buffered designs are considered. Several optical connection approaches are presented. Photographs of several representative optical connectors are included. Light Emitting Diode and Laser Diode emitters for fiber-optic applications are reviewed, and some advantages and shortcomings of each are considered. The phenomenon of modal noise is briefly explained. Both PIN and Avalanche photodetectors are reviewed and their performance parameters compared. Methods of data transmission over optical fiber are introduced. Principles of Wavelength, Frequency, and Time Division Multiplexing are briefly presented. The technology of fiber-optic sensors is briefly reviewed with basic principles introduced. The performance of a fiber-optic strain sensor is included as a practical example. 7 refs., 10 figs.

  7. Parametric Modeling of the Mouse Left Ventricular Myocardial Fiber Structure.

    PubMed

    Merchant, Samer S; Gomez, Arnold David; Morgan, James L; Hsu, Edward W

    2016-09-01

    Magnetic resonance diffusion tensor imaging (DTI) has greatly facilitated detailed quantifications of myocardial structures. However, structural patterns, such as the distinctive transmural rotation of the fibers, remain incompletely described. To investigate the validity and practicality of pattern-based analysis, 3D DTI was performed on 13 fixed mouse hearts and fiber angles in the left ventricle were transformed and fitted to parametric expressions constructed from elementary functions of the prolate spheroidal spatial variables. It was found that, on average, the myocardial fiber helix angle could be represented to 6.5° accuracy by the equivalence of a product of 10th-order polynomials of the radial and longitudinal variables, and 17th-order Fourier series of the circumferential variable. Similarly, the fiber imbrication angle could be described by 10th-order polynomials and 24th-order Fourier series, to 5.6° accuracy. The representations, while relatively concise, did not adversely affect the information commonly derived from DTI datasets including the whole-ventricle mean fiber helix angle transmural span and atlases constructed for the group. The unique ability of parametric models for predicting the 3D myocardial fiber structure from finite number of 2D slices was also demonstrated. These findings strongly support the principle of parametric modeling for characterizing myocardial structures in the mouse and beyond. PMID:26942586

  8. Squeezing in Optical Fibers

    NASA Astrophysics Data System (ADS)

    Boivin, Luc

    The generation of squeezed radiation in single -mode optical fibers is discussed. A self-consistent theory for the quantum propagation of pulses in dispersive and Raman active fibers is developed. A numerical implementation of the corresponding linearized noise theory is presented. This code was used to design a new fiber squeezer operating at 830nm. A closed-form solution to the nonlinear, stochastic and integro-differential equation for the quantum envelope is found at zero dispersion. We use this solution to study the resonance-fluorescence spectrum of a fiber excited by a monochromatic laser field. We also evaluate the mean field and the squeezing level for fiber lengths where the linearized approximation is no longer valid. The predictions of this continuous-time theory are compared with those of the discretized-time model. We show that quantum revivals predicted by the latter are spurious. We show that the linearized approximation in the soliton regime is valid for nonlinear phase shifts up to n_0^ {1/4}. The noise of the four soliton operators is shown to be minimized in a Poisson-Gaussian soliton state. We propose a new method for generating squeezed vacuum using a low birefringence fiber. This method relies on cross-phase modulation between modes with orthogonal polarizations, and does not require a interferometric geometry. We predict the nonlinear depolarization of an intense linearly polarized pulse coupled into a low birefringence fiber due to its interaction with quantum noise. Finally, progress in the construction of a fiber squeezer driven by a high repetition rate modelocked Ti:Sapphire laser is reported. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.).

  9. Yb-fiber laser pumped high-power, broadly tunable, single-frequency red source based on a singly resonant optical parametric oscillator.

    PubMed

    Shukla, Mukesh Kumar; Maji, Partha Sona; Das, Ritwick

    2016-07-01

    We present an efficient and tunable source generating multi-watt single-frequency red radiation by intra-cavity frequency doubling of the signal in a MgO-doped periodically poled LiNbO3 (MgO:PPLN)-based singly resonant optical parametric oscillator (SRO). By optimally designing the SRO cavity in a six-mirror configuration, we generate ≈276  nm tunable idler radiation in mid-infrared with a maximum power of Pi=2.05  W at a pump power of Pp=14.0  W. The resonant signal is frequency doubled using a 10 mm-long BiB3O6 (BiBO) crystal which resulted in tunability of a red beam from ≈753 to 780 nm band with maximum power Pr≈4.0  W recorded at λr≈756  nm. The deployment of a six-mirror SRO ensures single-frequency generation of red across the entire tuning range by inducing additional losses to Raman modes of LiNbO3 and, thus, inhibiting their oscillation. Using a scanning Fabry-Perot interferometer (FPI), nominal linewidth of the red beam is measured to ≈3  MHz which changes marginally over the entire tuning range. Long-term (over 1 h) peak-to-peak frequency fluctuation of the generated red beam is estimated to be about 3.3 GHz under free-running conditions at Pp=14.0  W. The generated red beam is delivered in a TEM00 mode profile with M2≤1.32 at maximum power in a red beam. PMID:27367094

  10. Optical Fiber Spectroscopy

    NASA Technical Reports Server (NTRS)

    Buoncristiani, A. M.

    1999-01-01

    This is the final report of work done on NASA Grant NAG-1-443. The work covers the period from July 1, 1992 to December 1, 1998. During this period several distinct but related research studies and work tasks were undertaken. These different subjects are enumerated below with a description of the work done on each of them. The focus of the research was the development of optical fibers for use as distributed temperature and stress sensors. The initial concept was to utilize the utilize the temperature and stress dependence of emission from rare earth and transition metal ions substitutionally doped into crystalline or glass fibers. During the course of investigating this it became clear that fiber Bragg gratings provided a alternative for making the desired measurements and there was a shift of research focus on to include the photo-refractive properties of germano-silicate glasses used for most gratings and to the possibility of developing fiber laser sources for an integrated optical sensor in the research effort. During the course of this work several students from Christopher Newport University and other universities participated in this effort. Their names are listed below. Their participation was an important part of their education.

  11. Fiber optic flocculation sensor

    NASA Astrophysics Data System (ADS)

    Cheng, Lun K.; Stelwagen, Uilke

    1994-02-01

    A fiber optic flocculation sensor based on measuring the intensity of light reflected by solid particles in suspension (i.e. paper pulp) in a well defined measurement volume, was constructed. This sensor is designed for monitoring the flocculation state of paper pulp in the papermaking process. The flocculation determines to a great extent the quality of the final product, the paper. Tests with different types of pulp were performed in both a closed loop system and a small paper machine. In this investigation the flocculation state is expressed as a root mean square flocculation index. The flocculation index delivered by this fiber optic system shows a very high correlation with the flocculation index provided by a camera system `looking at' the same pulp, while the latter has a great resemblance with the human perception of the flocculation.

  12. Fiber Optic Attenuators

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Mike Buzzetti designed a fiber optic attenuator while working at Jet Propulsion Laboratory, intended for use in NASA's Deep Space Network. Buzzetti subsequently patented and received an exclusive license to commercialize the device, and founded Nanometer Technologies to produce it. The attenuator functions without introducing measurable back-reflection or insertion loss, and is relatively insensitive to vibration and changes in temperature. Applications include cable television, telephone networks, other signal distribution networks, and laboratory instrumentation.

  13. Optical fiber laser

    SciTech Connect

    Hakimi, F.; Po, H.; Snitzer, E.

    1987-07-14

    An optical fiber laser is described comprising: a gain cavity including a single mode optical fiber of given length having a core with a given index of refraction and a cladding surrounding the core and having an index of refraction lower than that of the core. The core comprises a host glass having incorporated a laser gain material with a fluorescence spectrum having at least one broadband region in which there is at least one peak emission line; filter means optically coupled to one end of the gain cavity and reflective to radiation emitted from the gain material over a predetermined wavelength interval about the peak emission line to provide feedback in the gain cavity; an etalon filter section butt coupled to the remaining end of the gain cavity optical fiber, the etalon filter section comprising a pair of filters spaced apart in parallel by a predetermined length of material transparent to any radiation emitted from the gain cavity. The predetermined length of the transparent material is such that the etalon filter section is no longer than the distance over which the wave train energy from the fiber core remains substantially planar so that the etalon filter section is inside the divergent region to enhance feedback in the gain cavity; and means for pumping energy into the gain cavity to raise the interval energy level such that only a small part of the ion population, corresponding to a predetermined bandwidth about the peak emission line, is raised above laser threshold. The laser emits radiation only over narrow lines over a narrow wavelength interval centered about the peak emission line.

  14. Fiber optic geophysical sensors

    DOEpatents

    Homuth, Emil F.

    1991-01-01

    A fiber optic geophysical sensor in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects.

  15. Noncontact fiber optic micrometer

    NASA Astrophysics Data System (ADS)

    Betancourt Ibarra, F.; Guajardo-Gonzalez, Candelario; Castillo-Guzman, Arturo; Guzman-Ramos, Valentin; Selvas, Romeo

    2010-10-01

    A sensor instrument able to measuring the thickness of different semitransparent objects with a resolution of one micron is described. This is based on a fiber optic reflectometer and a laser autofocus system and permit to measuring the thickness of thin surfaces such as semiconductor films, plastic materials and semitransparent objects. The response time for the measuring was roughly 2 sec and the thickness results were compared with a digital mechanical micrometer and both are in good agreement.

  16. Optical parametric osicllators with improved beam quality

    DOEpatents

    Smith, Arlee V.; Alford, William J.

    2003-11-11

    An optical parametric oscillator (OPO) having an optical pump, which generates a pump beam at a pump frequency greater than a desired signal frequency, a nonlinear optical medium oriented so that a signal wave at the desired signal frequency and a corresponding idler wave are produced when the pump beam (wave) propagates through the nonlinear optical medium, resulting in beam walk off of the signal and idler waves, and an optical cavity which directs the signal wave to repeatedly pass through the nonlinear optical medium, said optical cavity comprising an equivalently even number of non-planar mirrors that produce image rotation on each pass through the nonlinear optical medium. Utilizing beam walk off where the signal wave and said idler wave have nonparallel Poynting vectors in the nonlinear medium and image rotation, a correlation zone of distance equal to approximately .rho.L.sub.crystal is created which, through multiple passes through the nonlinear medium, improves the beam quality of the OPO output.

  17. Shedding Light on Fiber Optics.

    ERIC Educational Resources Information Center

    Bunch, Robert M.

    1994-01-01

    Explains the principles of fiber optics as a medium for light-wave communication. Current uses of fiber systems on college campuses include voice, video, and local area network applications. A group of seven school districts in Minnesota are linked via fiber-optic cables. Other uses are discussed. (MLF)

  18. Experimental demonstration of nanosecond optical parametric amplifier in YCOB

    NASA Astrophysics Data System (ADS)

    Li, Huanhuan; Li, Shiguang; Ma, Xiuhua; Zhu, Xiaolei; Tu, Xiaoniu; Zheng, Yanqing

    2013-05-01

    In this letter, we provide the experimental demonstration of nanosecond optical parametric amplification in YCOB centered at 1572 nm. The optical gain characterization of YCOB crystal was simulated and tested in this optical parametric conversion. A saturated OPA gain of 2.4 was obtained. The results confirm that YCOB crystal has the potential to be used in a high-energy cascade of MOPA parametric amplifiers at 1572 nm.

  19. Selenium semiconductor core optical fibers

    SciTech Connect

    Tang, G. W.; Qian, Q. Peng, K. L.; Wen, X.; Zhou, G. X.; Sun, M.; Chen, X. D.; Yang, Z. M.

    2015-02-15

    Phosphate glass-clad optical fibers containing selenium (Se) semiconductor core were fabricated using a molten core method. The cores were found to be amorphous as evidenced by X-ray diffraction and corroborated by Micro-Raman spectrum. Elemental analysis across the core/clad interface suggests that there is some diffusion of about 3 wt % oxygen in the core region. Phosphate glass-clad crystalline selenium core optical fibers were obtained by a postdrawing annealing process. A two-cm-long crystalline selenium semiconductor core optical fibers, electrically contacted to external circuitry through the fiber end facets, exhibit a three times change in conductivity between dark and illuminated states. Such crystalline selenium semiconductor core optical fibers have promising utility in optical switch and photoconductivity of optical fiber array.

  20. Anisotropic metamaterial optical fibers.

    PubMed

    Pratap, Dheeraj; Anantha Ramakrishna, S; Pollock, Justin G; Iyer, Ashwin K

    2015-04-01

    Internal physical structure can drastically modify the properties of waveguides: photonic crystal fibers are able to confine light inside a hollow air core by Bragg scattering from a periodic array of holes, while metamaterial loaded waveguides for microwaves can support propagation at frequencies well below cutoff. Anisotropic metamaterials assembled into cylindrically symmetric geometries constitute light-guiding structures that support new kinds of exotic modes. A microtube of anodized nanoporous alumina, with nanopores radially emanating from the inner wall to the outer surface, is a manifestation of such an anisotropic metamaterial optical fiber. The nanopores, when filled with a plasmonic metal such as silver or gold, greatly increase the electromagnetic anisotropy. The modal solutions in such anisotropic circular waveguides can be uncommon Bessel functions with imaginary orders. PMID:25968741

  1. Fiber optic TV direct

    NASA Technical Reports Server (NTRS)

    Kassak, John E.

    1991-01-01

    The objective of the operational television (OTV) technology was to develop a multiple camera system (up to 256 cameras) for NASA Kennedy installations where camera video, synchronization, control, and status data are transmitted bidirectionally via a single fiber cable at distances in excess of five miles. It is shown that the benefits (such as improved video performance, immunity from electromagnetic interference and radio frequency interference, elimination of repeater stations, and more system configuration flexibility) can be realized if application of the proven fiber optic transmission concept is used. The control system will marry the lens, pan and tilt, and camera control functions into a modular based Local Area Network (LAN) control network. Such a system does not exist commercially at present since the Television Broadcast Industry's current practice is to divorce the positional controls from the camera control system. The application software developed for this system will have direct applicability to similar systems in industry using LAN based control systems.

  2. Optical fiber smartphone spectrometer.

    PubMed

    Hossain, Md Arafat; Canning, John; Cook, Kevin; Jamalipour, Abbas

    2016-05-15

    An optical fiber-based smartphone spectrometer incorporating an endoscopic fiber bundle is demonstrated. The endoscope allows transmission of the smartphone camera LED light to a sample, removing complications from varying background illumination. The reflected spectra collected from a surface or interface is dispersed onto the camera CMOS using a reflecting diffraction grating. A spectral resolution as low as δλ∼2.0  nm over a bandwidth of Δλ∼250  nm is obtained using a slit width, ωslit=0.7  mm. The instrument has vast potential in a number of industrial applications including agricultural produce analysis. Spectral analysis of apples shows straightforward measurement of the pigments anthocyanins, carotenoid, and chlorophyll, all of which decrease with increasing storage time. PMID:27176971

  3. Fiber optic light sensor.

    PubMed

    Chudyk, Wayne; Flynn, Kyle F

    2015-06-01

    We describe a low-cost fiber optic sensor for measuring photosynthetically active radiation (PAR) in turbulent flow. Existing technology was combined in a novel way for probe development addressing the need for a small but durable instrument for use in flowing water. Optical components including fiber optics and a wide-spectrum light detector were used to separate light collection from electronic detection so that measurements could be completed in either the field or laboratory, in air or underwater. Connection of the detector to Arduino open-source electronics and a portable personal computer (PC) enabled signal processing and allowed data to be stored in a spreadsheet for ease of analysis. Calibration to a commercial cosine-corrected instrument showed suitable agreement with the added benefit that the small sensor face allowed measurements in tight spaces such as close to the streambed or within leafy or filamentous plant growth. Subsequently, we applied the probe in a separate study where over 35 experiments were successfully completed to characterize downward light attenuation in filamentous algae in turbulent flow. PMID:26009160

  4. System for testing optical fibers

    DOEpatents

    Golob, J.E.; Looney, L.D.; Lyons, P.B.; Nelson, M.A.; Davies, T.J.

    1980-07-15

    A system for measuring a combination of optical transmission properties of fiber optic waveguides. A polarized light pulse probe is injected into one end of the optical fiber. Reflections from discontinuities within the fiber are unpolarized whereas reflections of the probe pulse incident to its injection remain polarized. The polarized reflections are prevented from reaching a light detector whereas reflections from the discontinuities reaches the detector. 2 figs.

  5. System for testing optical fibers

    DOEpatents

    Golob, John E. [Olathe, KS; Looney, Larry D. [Los Alamos, NM; Lyons, Peter B. [Los Alamos, NM; Nelson, Melvin A. [Santa Barbara, CA; Davies, Terence J. [Santa Barbara, CA

    1980-07-15

    A system for measuring a combination of optical transmission properties of fiber optic waveguides. A polarized light pulse probe is injected into one end of the optical fiber. Reflections from discontinuities within the fiber are unpolarized whereas reflections of the probe pulse incident to its injection remain polarized. The polarized reflections are prevented from reaching a light detector whereas reflections from the discontinuities reaches the detector.

  6. Fiber optic geophysical sensors

    DOEpatents

    Homuth, E.F.

    1991-03-19

    A fiber optic geophysical sensor is described in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects. 2 figures.

  7. Fiber optic photoplethysmograph

    NASA Astrophysics Data System (ADS)

    Bokun, Leszek J.; Domanski, Andrzej W.

    1991-07-01

    Using a very well known characteristic of infrared radiation absorbance by human skin versus the length of radiation wave and by application of the newest achievements of radiation detecting techniques and very fast computing techniques - the authors have designed and manufactured the complete computer system for noninvasive diagnosis of blood vessels in legs. As the basic unit in this system, fiber-optic photoplethysmograph was applied. The measurement method used here was very well described by V. Blazek and some other scientists. This article presents photoplethysmograph and all features of the computer system.

  8. A fiber optic damage monitor

    NASA Astrophysics Data System (ADS)

    Jen, C. K.; Cielo, P.; Farnell, G. W.; Parker, M.

    A simplified fiber-optic damage monitoring system for on-line assessments of the condition of composite structural materials in F/A-18 fighters is described. Optical fibers are implanted into the composite mesh in a configuration with horizontal and vertical orientations. When light is pumped into the fibers, and failure of transmittance in either the x- or y-coordinates indicates the location of a defect at that coordinate, as revealed by the fiber damage. Attaching photodiodes to the optic fibers and connecting the entire system to a video camera and computer permits on-line monitoring of the mesh-holding panels. Sample results are provided from a system with multimode step index fibers, a VAX 11/780 computer and a video camera with a 488 x 380 cell photodiode array. Image subtraction is an effective means for fast determination of the identities of broken fibers by comparisons of images of arrays of original and damaged fibers.

  9. Frequency comb metrology with an optical parametric oscillator.

    PubMed

    Balskus, K; Schilt, S; Wittwer, V J; Brochard, P; Ploetzing, T; Jornod, N; McCracken, R A; Zhang, Z; Bartels, A; Reid, D T; Südmeyer, T

    2016-04-18

    We report on the first demonstration of absolute frequency comb metrology with an optical parametric oscillator (OPO) frequency comb. The synchronously-pumped OPO operated in the 1.5-µm spectral region and was referenced to an H-maser atomic clock. Using different techniques, we thoroughly characterized the frequency noise power spectral density (PSD) of the repetition rate frep, of the carrier-envelope offset frequency fCEO, and of an optical comb line νN. The comb mode optical linewidth at 1557 nm was determined to be ~70 kHz for an observation time of 1 s from the measured frequency noise PSD, and was limited by the stability of the microwave frequency standard available for the stabilization of the comb repetition rate. We achieved a tight lock of the carrier envelope offset frequency with only ~300 mrad residual integrated phase noise, which makes its contribution to the optical linewidth negligible. The OPO comb was used to measure the absolute optical frequency of a near-infrared laser whose second-harmonic component was locked to the F = 2→3 transition of the 87Rb D2 line at 780 nm, leading to a measured transition frequency of νRb = 384,228,115,346 ± 16 kHz. We performed the same measurement with a commercial fiber-laser comb operating in the 1.5-µm region. Both the OPO comb and the commercial fiber comb achieved similar performance. The measurement accuracy was limited by interferometric noise in the fibered setup of the Rb-stabilized laser. PMID:27137274

  10. Optical Fiber Networks for Remote Fiber Optic Sensors

    PubMed Central

    Fernandez-Vallejo, Montserrat; Lopez-Amo, Manuel

    2012-01-01

    This paper presents an overview of optical fiber sensor networks for remote sensing. Firstly, the state of the art of remote fiber sensor systems has been considered. We have summarized the great evolution of these systems in recent years; this progress confirms that fiber-optic remote sensing is a promising technology with a wide field of practical applications. Afterwards, the most representative remote fiber-optic sensor systems are briefly explained, discussing their schemes, challenges, pros and cons. Finally, a synopsis of the main factors to take into consideration in the design of a remote sensor system is gathered. PMID:22666011

  11. Optical fiber networks for remote fiber optic sensors.

    PubMed

    Fernandez-Vallejo, Montserrat; Lopez-Amo, Manuel

    2012-01-01

    This paper presents an overview of optical fiber sensor networks for remote sensing. Firstly, the state of the art of remote fiber sensor systems has been considered. We have summarized the great evolution of these systems in recent years; this progress confirms that fiber-optic remote sensing is a promising technology with a wide field of practical applications. Afterwards, the most representative remote fiber-optic sensor systems are briefly explained, discussing their schemes, challenges, pros and cons. Finally, a synopsis of the main factors to take into consideration in the design of a remote sensor system is gathered. PMID:22666011

  12. Fiber optic to integrated optical chip coupler

    NASA Technical Reports Server (NTRS)

    Pikulski, Joseph I. (Inventor); Ramer, O. Glenn (Inventor)

    1987-01-01

    Optical fibers are clamped by a block onto a substrate. Thereupon, metal is plated over the fibers to hold them in place upon the substrate. The clamp block is removed and the opening, resulting from the clamp block's presence, is then plated in. The built-up metallic body is a coupling which holds the fibers in position so that the ends can be polished for coupling to an integrated optical chip upon a coupling fixture.

  13. Fiber optic control system integration

    NASA Technical Reports Server (NTRS)

    Poppel, G. L.; Glasheen, W. M.; Russell, J. C.

    1987-01-01

    A total fiber optic, integrated propulsion/flight control system concept for advanced fighter aircraft is presented. Fiber optic technology pertaining to this system is identified and evaluated for application readiness. A fiber optic sensor vendor survey was completed, and the results are reported. The advantages of centralized/direct architecture are reviewed, and the concept of the protocol branch is explained. Preliminary protocol branch selections are made based on the F-18/F404 application. Concepts for new optical tools are described. Development plans for the optical technology and the described system are included.

  14. Fabrication of Optical Fiber Devices

    NASA Astrophysics Data System (ADS)

    Andres, Miguel V.

    In this paper we present the main research activities of the Laboratorio de Fibras Opticas del Instituto de Ciencia de los Materiales de la Universidad de Valencia. We show some of the main results obtained for devices based on tapered fibers, fiber Bragg gratings, acousto-optic effects and photonic crystal fibers.

  15. Multisection optical parametric-Raman hybrid amplifier for terabit+ WDM systems

    NASA Astrophysics Data System (ADS)

    Kaur, Gaganpreet; Kaur, Gurmeet; Sharma, Sanjay

    2016-05-01

    We demonstrate flat-gain wide bandwidth Raman-Fiber optical parametric hybrid amplifier for wavelength division multiplexed systems (WDM). Raman-parametric amplifiers exploit system non-linearities which are otherwise inevitable in evolving WDM systems. Investigations show that the pumps of parametric amplifier and Raman amplifier can be carefully selected at wavelengths, to give gain over complementary bandwidth regions, resulting in wide bandwidth with low gain ripple. Results show a flat gain of 24.3 dB for 12 × 100 Gbps WDM system with lowest ripple of less than 2.78 dB reported over 220 nm bandwidth for Raman-FOPA hybrid.

  16. Ultrafast Airy beam optical parametric oscillator

    PubMed Central

    Apurv Chaitanya, N.; Kumar, S. Chaitanya; Aadhi, A.; Samanta, G. K.; Ebrahim-Zadeh, M.

    2016-01-01

    We report on the first realization of an ultrafast Airy beam optical parametric oscillator (OPO). By introducing intracavity cubic phase modulation to the resonant Gaussian signal in a synchronously-pumped singly-resonant OPO cavity and its subsequent Fourier transformation, we have generated 2-dimensional Airy beam in the output signal across a 250 nm tuning range in the near-infrared. The generated Airy beam can be tuned continuously from 1477 to 1727 nm, providing an average power of as much as 306 mW at 1632 nm in pulses of ~23 ps duration with a spectral bandwidth of 1.7 nm. PMID:27476910

  17. Ultrafast Airy beam optical parametric oscillator.

    PubMed

    Apurv Chaitanya, N; Kumar, S Chaitanya; Aadhi, A; Samanta, G K; Ebrahim-Zadeh, M

    2016-01-01

    We report on the first realization of an ultrafast Airy beam optical parametric oscillator (OPO). By introducing intracavity cubic phase modulation to the resonant Gaussian signal in a synchronously-pumped singly-resonant OPO cavity and its subsequent Fourier transformation, we have generated 2-dimensional Airy beam in the output signal across a 250 nm tuning range in the near-infrared. The generated Airy beam can be tuned continuously from 1477 to 1727 nm, providing an average power of as much as 306 mW at 1632 nm in pulses of ~23 ps duration with a spectral bandwidth of 1.7 nm. PMID:27476910

  18. Ultrafast Airy beam optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Apurv Chaitanya, N.; Kumar, S. Chaitanya; Aadhi, A.; Samanta, G. K.; Ebrahim-Zadeh, M.

    2016-08-01

    We report on the first realization of an ultrafast Airy beam optical parametric oscillator (OPO). By introducing intracavity cubic phase modulation to the resonant Gaussian signal in a synchronously-pumped singly-resonant OPO cavity and its subsequent Fourier transformation, we have generated 2-dimensional Airy beam in the output signal across a 250 nm tuning range in the near-infrared. The generated Airy beam can be tuned continuously from 1477 to 1727 nm, providing an average power of as much as 306 mW at 1632 nm in pulses of ~23 ps duration with a spectral bandwidth of 1.7 nm.

  19. Experimental optical fiber communications link

    NASA Technical Reports Server (NTRS)

    Lutes, G. F.

    1980-01-01

    An optical fiber communications link 1.5 kilometers in length was installed between the Interim Frequency Standard Test Facility and the Timing and Frequency Systems Research Laboratory at JPL. It is being used to develop optical fiber technology for use in the DSN and particularly for precise time and frequency distribution.

  20. Fiber-optic proximity sensor

    NASA Technical Reports Server (NTRS)

    Bejczy, A. K.; Hermann, W. A.; Primus, H. C.

    1980-01-01

    Proximity sensor for mechanical hand of remote manipulator incorporates fiber optics to conduct signals between light source and light detector. Fiber optics are not prone to noise from electromagnetic interference and radio-frequency interference as are sensors using long electrical cables.

  1. Fiber-optic measurement standards

    NASA Astrophysics Data System (ADS)

    Pollitt, Stuart

    1991-09-01

    Measurement needs, some very novel, arise at all stages of the development, manufacture, commercial exploitation and use of optical fibers. Measurement standards for fiber parameters enable users and manufacturers to verify the accuracy of their results and, hence, have confidence in their measurements. The facilities developed at the National Physical Laboratory to provide measurement standards for the physical and transmission properties of optical fibers are described and the sources of error are discussed.

  2. Fiber optic combiner and duplicator

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The investigation of the possible development of two optical devices, one to take two images as inputs and to present their arithmetic sum as a single output, the other to take one image as input and present two identical images as outputs is described. Significant engineering time was invested in establishing precision fiber optics drawing capabilities, real time monitoring of the fiber size and exact measuring of fiber optics ribbons. Various assembly procedures and tooling designs were investigated and prototype models were built and evaluated that established technical assurance that the device was feasible and could be fabricated. Although the interleaver specification in its entirety was not achieved, the techniques developed in the course of the program improved the quality of images transmitted by fiber optic arrays by at least an order of magnitude. These techniques are already being applied to the manufacture of precise fiber optic components.

  3. Python fiber-optic seal

    SciTech Connect

    Ystesund, K.; Bartberger, J.; Brusseau, C.; Fleming, P.; Insch, K.; Tolk, K.

    1993-12-31

    Sandia National Laboratories (SNL) has developed a high-security fiber-optic seal that incorporates tamper-resistance features not available in commercial fiber-optic seals. The Python Seal is a passive fiber-optic loop seal designed to give indication of unauthorized entry. The seal includes a fingerprint feature that provides seal identity information in addition to the unique fiber-optic pattern created when the seal is installed. The fiber-optic cable used for the seal loop is produced with tamper-resistant features that increase the difficulty of attacking this component of a seal. A Seal Reader has been developed that records the seal signature and the fingerprint feature of the seal. A Correlator software program compares seal images to establish a match or mismatch. SNL also is developing a Polaroid Reader to permit hard copies of the seal patterns to be obtained directly from the seal.

  4. Advances In Optical Fiber Sensors

    NASA Astrophysics Data System (ADS)

    Cole, J. H.; Giallorenzi, T. G.; Bucaro, J. A.

    1981-07-01

    Over the past several years, a new non-communication optical fiber application has emerged. This application utilizes optical fibers for sensing. Initial interest centered around rate rotation sensing. Since that time, however, acoustic, magnetic, and temperature sensing utilizing optical fibers has evolved into a viable research effort with significant potential payoff. As an example, laboratory fiber optic acoustic sensors now rival the best sensitivity obtained with piezoelectric ceramics. These sensors possess a unique geometric versatility previously unavailable. In conjunction with the Defense Advanced Research Projects Agency (DARPA), the Navy has begun a Fiber Optic Sensor System (FOSS) program to develop associated technology necessary to realize these sensors. Substantial effort is ongoing at the Naval Research Laboratory (NRL) and other Navy laboratories with considerable contractual effort from universities and industry. This paper reviews the status of the FOSS program.

  5. Fiber optic sensor and method for making

    DOEpatents

    Vartuli, James Scott; Bousman, Kenneth Sherwood; Deng, Kung-Li; McEvoy, Kevin Paul; Xia, Hua

    2010-05-18

    A fiber optic sensor including a fiber having a modified surface integral with the fiber wherein the modified surface includes an open pore network with optical agents dispersed within the open pores of the open pore network. Methods for preparing the fiber optic sensor are also provided. The fiber optic sensors can withstand high temperatures and harsh environments.

  6. Hydrogen Optical Fiber Sensors

    SciTech Connect

    Lieberman, Robert A.; Beshay, Manal; Cordero, Steven R.

    2008-07-28

    Optically-based hydrogen sensors promise to deliver an added level of safety as hydrogen and fuel cell technologies enter the mainstream. More importantly, they offer reduced power consumption and lower cost, which are desirable for mass production applications such as automobiles and consumer appliances. This program addressed two of the major challenges previously identified in porous optrode-based optical hydrogen sensors: sensitivity to moisture (ambient humidity), and interference from the oxygen in air. Polymer coatings to inhibit moisture and oxygen were developed in conjunction with newer and novel hydrogen sensing chemistries. The results showed that it is possible to achieve sensitive hydrogen detection and rapid response with minimal interference from oxygen and humidity. As a result of this work, a new and more exciting avenue of investigation was developed: the elimination of the porous optrode and deposition of the sensor chemistry directly into the polymer film. Initial results have been promising, and open up a wider range of potential applications from extended optical fiber sensing networks, to simple plastic "stickers" for use around the home and office.

  7. Optical fiber inspection system

    DOEpatents

    Moore, F.W.

    1985-04-05

    A remote optical inspection system including an inspection head. The inspection head has a passageway through which pellets or other objects are passed. A window is provided along the passageway through which light is beamed against the objects being inspected. A plurality of lens assemblies are arranged about the window so that reflected light can be gathered and transferred to a plurality of coherent optical fiber light guides. The light guides transfer the light images to a television or other image transducer which converts the optical images into a representative electronic signal. The electronic signal can then be displayed on a signal viewer such as a television monitor for inspection by a person. A staging means can be used to support the objects for viewing through the window. Routing means can be used to direct inspected objects into appropriate exit passages for accepted or rejected objects. The inspected objects are advantageously fed in a singular manner to the staging means and routing means. The inspection system is advantageously used in an enclosure when toxic or hazardous materials are being inspected. 10 figs.

  8. Optical fiber inspection system

    DOEpatents

    Moore, Francis W.

    1987-01-01

    A remote optical inspection system including an inspection head. The inspection head has a passageway through which pellets or other objects are passed. A window is provided along the passageway through which light is beamed against the objects being inspected. A plurality of lens assemblies are arranged about the window so that reflected light can be gathered and transferred to a plurality of coherent optical fiber light guides. The light guides transfer the light images to a television or other image transducer which converts the optical images into a representative electronic signal. The electronic signal can then be displayed on a signal viewer such as a television monitor for inspection by a person. A staging means can be used to support the objects for viewing through the window. Routing means can be used to direct inspected objects into appropriate exit passages for accepted or rejected objects. The inspected objects are advantageously fed in a singular manner to the staging means and routing means. The inspection system is advantageously used in an enclosure when toxic or hazardous materials are being inspected.

  9. Fiber optic hydrogen sensor

    SciTech Connect

    Butler, M.A.; Sanchez, R.; Dulleck, G.R.

    1996-05-01

    This report covers the development of fiber optic hydrogen and temperature sensors for monitoring dissolved hydrogen gas in transformer oil. The concentration of hydrogen gas is a measure of the corona and spark discharge within the transformer and reflects the state of health of the transformer. Key features of the instrument include use of palladium alloys to enhance hydrogen sensitivity, a microprocessor controlled instrument with RS-232, liquid crystal readout, and 4-20 ma. current loop interfaces. Calibration data for both sensors can be down loaded to the instrument through the RS-232 interface. This project was supported by the Technology Transfer Initiative in collaboration with J. W. Harley, Inc. through the mechanism of a cooperative research and development agreement (CRADA).

  10. Fiber optic-based biosensor

    NASA Technical Reports Server (NTRS)

    Ligler, Frances S.

    1991-01-01

    The NRL fiber optic biosensor is a device which measures the formation of a fluorescent complex at the surface of an optical fiber. Antibodies and DNA binding proteins provide the mechanism for recognizing an analyze and immobilizing a fluorescent complex on the fiber surface. The fiber optic biosensor is fast, sensitive, and permits analysis of hazardous materials remote from the instrumentation. The fiber optic biosensor is described in terms of the device configuration, chemistry for protein immobilization, and assay development. A lab version is being used for assay development and performance characterization while a portable device is under development. Antibodies coated on the fiber are stable for up to two years of storage prior to use. The fiber optic biosensor was used to measure concentration of toxins in the parts per billion (ng/ml) range in under a minute. Immunoassays for small molecules and whole bacteria are under development. Assays using DNA probes as the detection element can also be used with the fiber optic sensor, which is currently being developed to detect biological warfare agents, explosives, pathogens, and toxic materials which pollute the environment.

  11. Fiber-optic fluorescence imaging

    PubMed Central

    Flusberg, Benjamin A; Cocker, Eric D; Piyawattanametha, Wibool; Jung, Juergen C; Cheung, Eunice L M; Schnitzer, Mark J

    2010-01-01

    Optical fibers guide light between separate locations and enable new types of fluorescence imaging. Fiber-optic fluorescence imaging systems include portable handheld microscopes, flexible endoscopes well suited for imaging within hollow tissue cavities and microendoscopes that allow minimally invasive high-resolution imaging deep within tissue. A challenge in the creation of such devices is the design and integration of miniaturized optical and mechanical components. Until recently, fiber-based fluorescence imaging was mainly limited to epifluorescence and scanning confocal modalities. Two new classes of photonic crystal fiber facilitate ultrashort pulse delivery for fiber-optic two-photon fluorescence imaging. An upcoming generation of fluorescence imaging devices will be based on microfabricated device components. PMID:16299479

  12. Optical fiber dispersion characterization study

    NASA Technical Reports Server (NTRS)

    Geeslin, A.; Arriad, A.; Riad, S. M.; Padgett, M. E.

    1979-01-01

    The theory, design, and results of optical fiber pulse dispersion measurements are considered. Both the hardware and software required to perform this type of measurement are described. Hardware includes a thermoelectrically cooled injection laser diode source, an 800 GHz gain bandwidth produce avalanche photodiode and an input mode scrambler. Software for a HP 9825 computer includes fast Fourier transform, inverse Fourier transform, and optimal compensation deconvolution. Test set construction details are also included. Test results include data collected on a 1 Km fiber, a 4 Km fiber, a fused spliced, eight 600 meter length fibers concatenated to form 4.8 Km, and up to nine optical connectors.

  13. Critical reviews of fiber-optic communication technology Optical fibers

    NASA Astrophysics Data System (ADS)

    Kapron, F. P.

    The review begins with brief highlights of the history of fiber optics, followed by a discussion of the attributes of shortwave and longwave transmission. This leads to an investigation of various fiber types, short-haul considerations, and then single-mode aspects. Specialty fiber is briefly covered, followed by a survey of several research trends today that will lead to new systems capabilities in the future. No references are given, since hundreds would be necessary to make the list even partially complete.

  14. Harmonic generation in optical fibers

    SciTech Connect

    Sherborn, H.P.

    1990-05-01

    This patent describes an apparatus for providing second harmonic generated radiation. It comprises: an optical fiber disposed in a laser cavity, the optical fiber having a substantially single-mode core which is doped with an active laser material, the laser material being self-organizable to produce radiation by second harmonic generation, the laser material further being substantially transparent to the second harmonic generated radiation; and means for pumping the core of the optical fiber to produce laser radiation therein and the laser cavity further comprising means for extracting at least a portion of the second harmonic generated radiation.

  15. Communications satellites versus fiber optics

    NASA Astrophysics Data System (ADS)

    Goldman, A. M., Jr.

    Examples of the interfaces encountered in the provision of intercity, long-distance service in the U.S. are examined, and a comparison is conducted of the costs of the Intercity, Long-Distance portion of a single voice circuit derived from either fixed satellite trunking service or fiber optic bulk capacity. It is estimated that by the end of 1988, fiber optic should span the nation connecting New York and Washington with Los Angeles and San Francisco. It is shown that once fiber connects a given pair of cities, it becomes the least costly transmission medium, especially compared to fixed satellite service. Attention is given to equivalent transmission capacities, six providers of fiber optic capacity, a total satellite capacity comparison, an economic lifetime comparison, satellite and fiber optic network maps, satellite city-pair distance and cost matrices, and fiber optic city-pair distance matrices. It is pointed out that certain future CONUS satellite service applications will be inherently invulnerable to terrestrial fiber optics serving fixed routes.

  16. Silica optical fibers: technology update

    NASA Astrophysics Data System (ADS)

    Krohn, David A.; McCann, Brian P.

    1995-05-01

    Silica-core optical fibers have long been the standard delivery medium for medical laser delivery systems. Their high strength, excellent flexibility, and low cost continue to make them the fiber of choice for systems operating from 300 to 2200 nm. An overview of the current fiber constructions available to the industry is reviewed. Silicone-clad fibers, hard- fluoropolymer clad fibers and silica-clad fibers are briefly compared in terms of mechanical and optical properties. The variety of fiber coatings available is also discussed. A significant product development of silica fiber delivery systems has been in side-firing laser delivery systems for Urology. These devices utilize silica-core fibers to project the laser energy at a substantial lateral angle to the conventional delivery system, typically 40 to 100 degrees off axis. Many unique distal tips have been designed to meet the needs of this potentially enormous application. There are three primary technologies employed in side-firing laser delivery systems: reflection off of an attached medium; reflection within an angle-polished fiber through total internal reflection; and reflection from both an angle-polished fiber and an outside medium. Each technology is presented and compared on the basis of operation modality, transmission efficiency, and power-handling performance.

  17. Cascade frequency generation regime in an optical parametric oscillator

    SciTech Connect

    Kolker, D B; Dmitriev, Aleksandr K; Gorelik, P; Vong, Franko; Zondy, J J

    2009-05-31

    In a parametric oscillator of a special two-sectional design based on a lithium niobate periodic structure, a cascade frequency generation regime was observed in which a signal wave pumped a secondary parametric oscillator, producing secondary signal and idler waves. The secondary parametric oscillator can be tuned in a broad range of {approx}200 nm with respect to a fixed wavelength of the primary idler wave. (nonlinear optical phenomena)

  18. Program Predicts Performance of Optical Parametric Oscillators

    NASA Technical Reports Server (NTRS)

    Cross, Patricia L.; Bowers, Mark

    2006-01-01

    A computer program predicts the performances of solid-state lasers that operate at wavelengths from ultraviolet through mid-infrared and that comprise various combinations of stable and unstable resonators, optical parametric oscillators (OPOs), and sum-frequency generators (SFGs), including second-harmonic generators (SHGs). The input to the program describes the signal, idler, and pump beams; the SFG and OPO crystals; and the laser geometry. The program calculates the electric fields of the idler, pump, and output beams at three locations (inside the laser resonator, just outside the input mirror, and just outside the output mirror) as functions of time for the duration of the pump beam. For each beam, the electric field is used to calculate the fluence at the output mirror, plus summary parameters that include the centroid location, the radius of curvature of the wavefront leaving through the output mirror, the location and size of the beam waist, and a quantity known, variously, as a propagation constant or beam-quality factor. The program provides a typical Windows interface for entering data and selecting files. The program can include as many as six plot windows, each containing four graphs.

  19. Optical parametric oscillators for medical applications

    NASA Astrophysics Data System (ADS)

    Gloster, Lawrie A. W.; Golding, Paul S.; King, Terence A.

    1996-04-01

    In recent years optical parametric oscillators (OPOs) have undergone a renaissance largely due to the discovery of new nonlinear materials capable of wide continuous tuning ranges spanning from the UV to the near-infrared spectral regions. To date, however, OPOs have not been exploited in the medical field despite their advantages over the dye laser in terms of tuning range and solid state structure. We consider the development of an OPO based on barium borate (BBO) which can be tailored to suit applications in medicine. Converting the maximum number of pump photons to tunable signal and idler photons is of great importance to secure high-fluence radiation necessary for many treatments. With this in mind, we report on an all- solid-state system using BBO which has been optimized by computer modeling with the potential of delivering amplification factors of typically up to 20 over a continuous tuning range of 700 nm to 1000 nm. As an example of its biomedical application, we describe the selective excitation of biomolecules and chromophores for cell destruction using malachite green isothiocyanate labelled bacteria. The potential for development is reviewed towards other medical applications such as diagnostic sensing and phototherapy.

  20. Optical-Fiber-Welding Machine

    NASA Technical Reports Server (NTRS)

    Goss, W. C.; Mann, W. A.; Goldstein, R.

    1985-01-01

    Technique yields joints with average transmissivity of 91.6 percent. Electric arc passed over butted fiber ends to melt them together. Maximum optical transmissivity of joint achieved with optimum choice of discharge current, translation speed, and axial compression of fibers. Practical welding machine enables delicate and tedious joining operation performed routinely.

  1. System for testing optical fibers

    DOEpatents

    Davies, Terence J.; Franks, Larry A.; Nelson, Melvin A.

    1981-01-01

    A system for nondestructively determining the attenuation coefficient, .alpha.(.lambda.), of low-loss optical fiber wave guides. Cerenkov light pulses are generated at a plurality of locations in the fiber by a beam of charged particles. The transit times of selected spectral components and their intensities are utilized to unfold the .alpha.(.lambda.) values over the measured spectrum.

  2. Fiber optic refractive index monitor

    DOEpatents

    Weiss, Jonathan David

    2002-01-01

    A sensor for measuring the change in refractive index of a liquid uses the lowest critical angle of a normal fiber optic to achieve sensitivity when the index of the liquid is significantly less than the index of the fiber core. Another embodiment uses a liquid filled core to ensure that its index is approximately the same as the liquid being measured.

  3. Fiber Optics: A Bright Future.

    ERIC Educational Resources Information Center

    Rice, James, Jr.

    1980-01-01

    Presents an overview of the impact of fiber optics on telecommunications and its application to information processing and library services, including information retrieval, news services, remote transmission of library services, and library networking. (RAA)

  4. Scintillator fiber optic long counter

    DOEpatents

    McCollum, T.; Spector, G.B.

    1994-03-29

    A flat response position sensitive neutron detector capable of providing neutron spectroscopic data utilizing scintillator fiber optic filaments embedded in a neutron moderating housing having an open end through which neutrons enter to be detected is described. 11 figures.

  5. Scintillator fiber optic long counter

    DOEpatents

    McCollum, Tom; Spector, Garry B.

    1994-01-01

    A flat response position sensitive neutron detector capable of providing neutron spectroscopic data utilizing scintillator fiber optic filaments embedded in a neutron moderating housing having an open end through which neutrons enter to be detected.

  6. Application of Fiber Optic Instrumentation

    NASA Technical Reports Server (NTRS)

    Richards, William Lance; Parker, Allen R., Jr.; Ko, William L.; Piazza, Anthony; Chan, Patrick

    2012-01-01

    Fiber optic sensing technology has emerged in recent years offering tremendous advantages over conventional aircraft instrumentation systems. The advantages of fiber optic sensors over their conventional counterparts are well established; they are lighter, smaller, and can provide enormous numbers of measurements at a fraction of the total sensor weight. After a brief overview of conventional and fiber-optic sensing technology, this paper presents an overview of the research that has been conducted at NASA Dryden Flight Research Center in recent years to advance this promising new technology. Research and development areas include system and algorithm development, sensor characterization and attachment, and real-time experimentally-derived parameter monitoring for ground- and flight-based applications. The vision of fiber optic smart structure technology is presented and its potential benefits to aerospace vehicles throughout the lifecycle, from preliminary design to final retirement, are presented.

  7. Mobile fiber optic emission spectrograph

    SciTech Connect

    Spencer, W.A.; Coleman, C.J.; McCarty, J.E.; Beck, R.S.

    1997-05-01

    Technical Assistance Request HLW/DWPF-TAR-970064 asked SRTC to evaluate the use of a fiber optic coupled emission spectrometer. The spectrometer would provide additional ICP analyses in the DWPF laboratory.

  8. Arc detector uses fiber optics

    NASA Technical Reports Server (NTRS)

    Finnegan, E. J.; Leech, R. A.

    1979-01-01

    Arc detector for protecting high-power microwave klystron oscillators uses fiber optics connected to remote solid-state light-sensing circuits. Detector is more reliable, smaller, and sensitive than other systems that locate detector in waveguide.

  9. Fiber-optic temperature sensor

    SciTech Connect

    O`Rourke, P.E.; Livingston, R.R.; Jantzen, C.M.; Ramsey, W.G.; Hopkins, C.D.

    1993-10-01

    Researchers at the Savannah River Technology Center (SRTC) have developed a class of fiber-optic temperature sensors based upon temperature induced changes in the absorption spectrum of selected materials. For example, a neodymium (Nd) doped glass sensor can be used over a very broad temperature range ({minus}196 to 500{degree}C) and provide good precision and accuracy ({plus_minus}1{degree}C). This type temperature probe is constructed so that light from a fiber optic cable shines through the Nd glass and is reflected onto a second fiber optic cable. Light from this second fiber optic is measured by a diode array spectrophotometer, and the absorption spectrum of the Nd glass used to compute temperature.

  10. Light diffusing fiber optic chamber

    DOEpatents

    Maitland, Duncan J.

    2002-01-01

    A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

  11. Small Business Innovations (Fiber Optics)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Foster-Miller, Inc. Waltham, MA developed the In-Situ Fiber Optic Polymer Reaction Monitor which could lead to higher yields and lower costs in complex composite manufacturing. The monitor, developed under a Small Business Innovation Research (SBIR) contract with Langley Research Center, uses an infrared, fiber optic sensor to track the molecular vibrational characteristics of a composite part while it is being cured. It is the first analytical system capable of directly measuring the chemistry of advanced composite materials.

  12. Fiber optics for advanced aircraft

    NASA Technical Reports Server (NTRS)

    Baumbick, Robert J.

    1988-01-01

    The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

  13. Fiber optics for advanced aircraft

    NASA Technical Reports Server (NTRS)

    Baumbick, Robert J.

    1989-01-01

    The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

  14. Fiber optic diffraction grating maker

    DOEpatents

    Deason, Vance A.; Ward, Michael B.

    1991-01-01

    A compact and portable diffraction grating maker comprised of a laser beam, optical and fiber optics devices coupling the beam to one or more evanescent beam splitters, and collimating lenses or mirrors directing the split beam at an appropriate photosensitive material. The collimating optics, the output ends of the fiber optic coupler and the photosensitive plate holder are all mounted on an articulated framework so that the angle of intersection of the beams can be altered at will without disturbing the spatial filter, collimation or beam quality, and assuring that the beams will always intersect at the position of the plate.

  15. Fiber optic diffraction grating maker

    DOEpatents

    Deason, V.A.; Ward, M.B.

    1991-05-21

    A compact and portable diffraction grating maker is comprised of a laser beam, optical and fiber optics devices coupling the beam to one or more evanescent beam splitters, and collimating lenses or mirrors directing the split beam at an appropriate photosensitive material. The collimating optics, the output ends of the fiber optic coupler and the photosensitive plate holder are all mounted on an articulated framework so that the angle of intersection of the beams can be altered at will without disturbing the spatial filter, collimation or beam quality, and assuring that the beams will always intersect at the position of the plate. 4 figures.

  16. Optical filtering enabled by cascaded parametric amplification.

    PubMed

    McKinstrie, C J; Dailey, J M; Agarwal, A; Toliver, P

    2016-06-27

    A cascaded parametric amplifier consists of a first parametric amplifier, which amplifies an input signal and generates an idler, which is a copy of the signal, a signal processor, which controls the phases of the signal and idler, and a second parametric amplifier, which combines the signal and idler in a phase-sensitive manner. In this paper, cascaded parametric amplification is modeled and the conditions required to maximize the constructive-destructive extinction ratio are determined. The results show that a cascaded parametric amplifier can be operated as a filter: A desired signal-idler pair is amplified, whereas undesired signal-idler pairs are deamplified. For the desired signal and idler, the noise figures of the filtering process (input signal-to-noise ratio divided by the output ratios) are only slightly higher than those of the copying process: Signal-processing functionality can be achieved with only a minor degradation in signal quality. PMID:27410581

  17. Fiber optic frequency transfer link

    NASA Technical Reports Server (NTRS)

    Primas, Lori E. (Inventor); Sydnor, Richard L. (Inventor); Lutes, George F. (Inventor)

    1991-01-01

    A reference frequency distribution system is disclosed for transmitting a reference frequency from a reference unit to a remote unit while keeping the reference frequency at the reference unit and the remote unit in phase. A fiber optic cable connects the reference unit to the remote unit. A frequency source at the reference unit produces a reference frequency having an adjustable phase. A fiber optic transmitter at the reference unit modulates a light beam with the reference frequency and transmits the light beam into the fiber optic cable. A 50/50 reflector at the remote unit reflects a first portion of the light beam from the reference unit back into the fiber optic cable to the reference unit. A first fiber optic receiver disposed at the remote unit receives a second portion of the light beam and demodulates the reference frequency to be used at the remote unit. A second fiber optic receiver disposed at the reference unit receives the first portion of the light beam and demodulates a reference frequency component. A phase conjugator is connected to the frequency source for comparing the phase of the reference frequency component to the phase of the reference frequency modulating the light beam being transmitted from the reference unit to maintain a conjugate (anti-symmetric) relationship between the reference frequency component and the reference frequency modulating the light beam where virtually no phase difference exists between the phase of the reference frequency component and the phase of the reference frequency modulating the light beam.

  18. Sensitivity enhancement in swept-source optical coherence tomography by parametric balanced detector and amplifier.

    PubMed

    Kang, Jiqiang; Wei, Xiaoming; Li, Bowen; Wang, Xie; Yu, Luoqin; Tan, Sisi; Jinata, Chandra; Wong, Kenneth K Y

    2016-04-01

    We proposed a sensitivity enhancement method of the interference-based signal detection approach and applied it on a swept-source optical coherence tomography (SS-OCT) system through all-fiber optical parametric amplifier (FOPA) and parametric balanced detector (BD). The parametric BD was realized by combining the signal and phase conjugated idler band that was newly-generated through FOPA, and specifically by superimposing these two bands at a photodetector. The sensitivity enhancement by FOPA and parametric BD in SS-OCT were demonstrated experimentally. The results show that SS-OCT with FOPA and SS-OCT with parametric BD can provide more than 9 dB and 12 dB sensitivity improvement, respectively, when compared with the conventional SS-OCT in a spectral bandwidth spanning over 76 nm. To further verify and elaborate their sensitivity enhancement, a bio-sample imaging experiment was conducted on loach eyes by conventional SS-OCT setup, SS-OCT with FOPA and parametric BD at different illumination power levels. All these results proved that using FOPA and parametric BD could improve the sensitivity significantly in SS-OCT systems. PMID:27446655

  19. Sensitivity enhancement in swept-source optical coherence tomography by parametric balanced detector and amplifier

    PubMed Central

    Kang, Jiqiang; Wei, Xiaoming; Li, Bowen; Wang, Xie; Yu, Luoqin; Tan, Sisi; Jinata, Chandra; Wong, Kenneth K. Y.

    2016-01-01

    We proposed a sensitivity enhancement method of the interference-based signal detection approach and applied it on a swept-source optical coherence tomography (SS-OCT) system through all-fiber optical parametric amplifier (FOPA) and parametric balanced detector (BD). The parametric BD was realized by combining the signal and phase conjugated idler band that was newly-generated through FOPA, and specifically by superimposing these two bands at a photodetector. The sensitivity enhancement by FOPA and parametric BD in SS-OCT were demonstrated experimentally. The results show that SS-OCT with FOPA and SS-OCT with parametric BD can provide more than 9 dB and 12 dB sensitivity improvement, respectively, when compared with the conventional SS-OCT in a spectral bandwidth spanning over 76 nm. To further verify and elaborate their sensitivity enhancement, a bio-sample imaging experiment was conducted on loach eyes by conventional SS-OCT setup, SS-OCT with FOPA and parametric BD at different illumination power levels. All these results proved that using FOPA and parametric BD could improve the sensitivity significantly in SS-OCT systems. PMID:27446655

  20. Fiber Ring Optical Gyroscope (FROG)

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The design, construction, and testing of a one meter diameter fiber ring optical gyro, using 1.57 kilometers of single mode fiber, are described. The various noise components: electronic, thermal, mechanical, and optical, were evaluated. Both dc and ac methods were used. An attempt was made to measure the Earth rotation rate; however, the results were questionable because of the optical and electronic noise present. It was concluded that fiber ring optical gyroscopes using all discrete components have many serious problems that can only be overcome by discarding the discrete approach and adapting an all integrated optic technique that has the laser source, modulator, detector, beamsplitters, and bias element on a single chip.

  1. Supercontinuum Generation in Optical Fibers

    NASA Astrophysics Data System (ADS)

    Dudley, J. M.; Taylor, J. R.

    2010-04-01

    1. Introduction and history J. R. Taylor; 2. Supercontinuum generation in microstructure fiber - an historical note J. K. Ranka; 3. Nonlinear fiber optics overview J. C. Travers, M. H. Frosz and J. M. Dudley; 4. Fiber supercontinuum generation overview J. M. Dudley; 5. Silica fibers for supercontinuum generation J. C. Knight and W. Wadsworth; 6. Supercontinuum generation and nonlinearity in soft glass fibers J. H. V. Price and D. J. Richardson; 7. Increasing the blue-shift of a picosecond pumped supercontinuum M. H. Frosz, P. M. Moselund, P. D. Rasmussen, C. L. Thomsen and O. Bang; 8. Continuous wave supercontinuum generation J. C. Travers; 9. Theory of supercontinuum and interactions of solitons with dispersive waves D. V. Skryabin and A. V. Gorbach; 10. Interaction of four-wave mixing and stimulated Raman scattering in optical fibers S. Coen, S. G. Murdoch and F. Vanholsbeeck; 11. Nonlinear optics in emerging waveguides: revised fundamentals and implications S. V. Afshar, M. Turner and T. M. Monro; 12. Supercontinuum generation in dispersion varying fibers G. Genty; 13. Supercontinuum generation in chalcogenide glass waveguides Dong-Il Yeom, M. R. E. Lamont, B. Luther Davies and B. J. Eggleton; 14. Supercontinuum generation for carrier-envelope phase stabilization of mode-locked lasers S. T. Cundiff; 15. Biophotonics applications of supercontinuum generation C. Dunsby and P. M. W. French; 16. Fiber sources of tailored supercontinuum in nonlinear microspectroscopy and imaging A. M. Zheltikov; Index.

  2. Optical Parametric Technology for Methane Measurements

    NASA Technical Reports Server (NTRS)

    Dawsey, Martha; Numata, Kenji; Wu, Stewart; Riris, Haris

    2015-01-01

    Atmospheric methane (CH4) is the second most important anthropogenic greenhouse gas, with approximately 25 times the radiative forcing of carbon dioxide (CO2) per molecule. Yet, lack of understanding of the processes that control CH4 sources and sinks and its potential release from stored carbon reservoirs contributes significant uncertainty to our knowledge of the interaction between carbon cycle and climate change. At Goddard Space Flight Center (GSFC) we have been developing the technology needed to remotely measure CH4 from orbit. Our concept for a CH4 lidar is a nadir viewing instrument that uses the strong laser echoes from the Earth's surface to measure CH4. The instrument uses a tunable, narrow-frequency light source and photon-sensitive detector to make continuous measurements from orbit, in sunlight and darkness, at all latitudes and can be relatively immune to errors introduced by scattering from clouds and aerosols. Our measurement technique uses Integrated Path Differential Absorption (IPDA), which measures the absorption of laser pulses by a trace gas when tuned to a wavelength coincident with an absorption line. We have already demonstrated ground-based and airborne CH4 detection using Optical Parametric Amplifiers (OPA) at 1651 nm using a laser with approximately 10 microJ/pulse at 5kHz with a narrow linewidth. Next, we will upgrade our OPO system to add several more wavelengths in preparation for our September 2015 airborne campaign, and expect that these upgrades will enable CH4 measurements with 1% precision (10-20 ppb).

  3. Optical parametric technology for methane measurements

    NASA Astrophysics Data System (ADS)

    Dawsey, Martha; Numata, Kenji; Wu, Stewart; Riris, Haris

    2015-09-01

    Atmospheric methane (CH4) is the second most important anthropogenic greenhouse gas, with approximately 25 times the radiative forcing of carbon dioxide (CO2) per molecule. Yet, lack of understanding of the processes that control CH4 sources and sinks and its potential release from stored carbon reservoirs contributes significant uncertainty to our knowledge of the interaction between carbon cycle and climate change. At Goddard Space Flight Center (GSFC) we have been developing the technology needed to remotely measure CH4 from orbit. Our concept for a CH4 lidar is a nadir viewing instrument that uses the strong laser echoes from the Earth's surface to measure CH4. The instrument uses a tunable, narrow-frequency light source and photon-sensitive detector to make continuous measurements from orbit, in sunlight and darkness, at all latitudes and can be relatively immune to errors introduced by scattering from clouds and aerosols. Our measurement technique uses Integrated Path Differential Absorption (IPDA), which measures the absorption of laser pulses by a trace gas when tuned to a wavelength coincident with an absorption line. We have already demonstrated ground-based and airborne CH4 detection using Optical Parametric Amplifiers (OPA) at 1651 nm using a laser with approximately 10 μJ/pulse at 5kHz with a narrow linewidth. Next, we will upgrade our OPO system to add several more wavelengths in preparation for our September 2015 airborne campaign, and expect that these upgrades will enable CH4 measurements with 1% precision (10-20 ppb).

  4. Fiber optic snapshot hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Mansur, David J.; Rentz Dupuis, Julia; Vaillancourt, Robert

    2012-06-01

    OPTRA is developing a snapshot hyperspectral imager (HSI) employing a fiber optic bundle and dispersive spectrometer. The fiber optic bundle converts a broadband spatial image to an array of fiber columns which serve as multiple entrance slits to a prism spectrometer. The dispersed spatially resolved spectra are then sampled by a two-dimensional focal plane array (FPA) at a greater than 30 Hz update rate, thereby qualifying the system as snapshot. Unlike snapshot HSI systems based on computed tomography or coded apertures, our approach requires only the remapping of the FPA frame into hyperspectral cubes rather than a complex reconstruction. Our system has high radiometric efficiency and throughput supporting sufficient signal to noise for hyperspectral imaging measurements made over very short integration times (< 33 ms). The overall approach is compact, low cost, and contains no moving parts, making it ideal for unmanned airborne surveillance. In this paper we present a preliminary design for the fiber optic snapshot HSI system.

  5. Bidirectional fiber optic cable adapter

    NASA Astrophysics Data System (ADS)

    Linehan, M.; Gee, N. B.; Taylor, R.

    1983-02-01

    The technical objective of the BIFOCS program was to develop, build, and test a full-duplex single fiber, fiber optic link, operating in the 1.0 micron to 1.6 micron region, capable of transmitting 20 Mb/s data (10 to the -9th power BER) over a range of at least 10 km, with a goal of 15 km. The link MTBF goal was 5 X 10 to the 3rd power hours and operation over a temperature range of 0 to 50 C. The fiber optic cable consisted of sections not exceeding 2 km in length joined by commercially available dry fiber optic connectors. The system performed successfully at ambient temperature over 15 km of cable.

  6. Fully automatic fiber optic polarization analyzer

    NASA Astrophysics Data System (ADS)

    Marć, P.; Jaroszewicz, L. R.; Stasiewicz, K.

    2008-04-01

    Since many years one of the topic our research team are multi-parametric fiber optic polarization sensors. In the paper is presented a new version of the Fiber-Optic Interferometric Polarization Analyzer (FOIPA). This system is based on modified Sagnac interferometer and it was equipped with automatic current driven polarization controllers driven by special analog output card and detection system based on data acquisition card and LabVIEW software. This system was called full automatic fiber optic interferometric polarization analyzer. Used in the system automatic, temperature driven polarization controllers allow working in feedback electronic loop with data acquisition system and they function as calibration and stabilization subsystem. Specially developed detection system allow measuring amplitudes of first three tones of the AC parts of two electric signals as well as they DC voltages. That advantages have given possibility replaced an expensive lock-in amplifier and make data performance and polarization parameters calculation more faster and easier. It was necessary to implement special procedure to proper SOP identification In the paper are presented theoretical and experimental analyzes of the uncertainties, also. Finally a comparison with commercially available polarization analyzer is shown.

  7. Monolithic fiber optic sensor assembly

    SciTech Connect

    Sanders, Scott

    2015-02-10

    A remote sensor element for spectrographic measurements employs a monolithic assembly of one or two fiber optics to two optical elements separated by a supporting structure to allow the flow of gases or particulates therebetween. In a preferred embodiment, the sensor element components are fused ceramic to resist high temperatures and failure from large temperature changes.

  8. Fiber optic gas sensor

    NASA Technical Reports Server (NTRS)

    Chen, Peng (Inventor); Buric, Michael P. (Inventor); Swinehart, Philip R. (Inventor); Maklad, Mokhtar S. (Inventor)

    2010-01-01

    A gas sensor includes an in-fiber resonant wavelength device provided in a fiber core at a first location. The fiber propagates a sensing light and a power light. A layer of a material is attached to the fiber at the first location. The material is able to absorb the gas at a temperature dependent gas absorption rate. The power light is used to heat the material and increases the gas absorption rate, thereby increasing sensor performance, especially at low temperatures. Further, a method is described of flash heating the gas sensor to absorb more of the gas, allowing the sensor to cool, thereby locking in the gas content of the sensor material, and taking the difference between the starting and ending resonant wavelengths as an indication of the concentration of the gas in the ambient atmosphere.

  9. Fiber optic crossbar switch for automatically patching optical signals

    NASA Astrophysics Data System (ADS)

    Bell, C. H.

    1983-05-01

    A system for automatically optically switching fiber optic data signals between a plurality of input optical fibers and selective ones of a plurality of output fibers is described. The system includes optical detectors which are connected to each of the input fibers for converting the optic data signals appearing at the respective input fibers to an RF signal. A plurality of RF to optical signal converters are arranged in rows and columns. The output of each of the optical detectors are each applied to a respective row of optical signal converted for being converters back to an optical signal when the particular optical signal converter is selectively activated by a dc voltage.

  10. Optical fiber feedback SQUID magnetometer

    SciTech Connect

    Naito, S.; Sampei, Y.; Takahashi, T. )

    1989-04-01

    This paper describes an optical fiber feedback superconducting quantum interference device (SQUID) magnetometer which was developed to improve electromagnetic interference characteristics. The SQUID consists of an RF SQUID probe, an RF amplifier, two multimode fibers, and a SQUID control unit. Phase-locked pulse width modulation (PWM) was used to construct a flux locked loop (FLL) circuit in the SQUID control unit. The operation of the optical fiber feedback SQUID is stable when a common mode voltage of ac 100 V/50 Hz is applied. It has an energy resolution of 1 x 10/sup -28/ J/Hz. This paper also describes the measurement of an auditory evoked field from the human brain in a magnetically shielded room using the fiber feedback SQUID with a gradiometer type pickup coil.

  11. Fiber-Optic Temperature Sensor

    NASA Technical Reports Server (NTRS)

    Maram, Jonathan M.

    1987-01-01

    Proposed sensor measures temperatures over wide range, from cryogenic liquids to burning gases. Made in part of optical fibers, sensor lighter in weight than thermocouple and immune to electromagnetic interference. Device does not respond to temperatures elsewhere than at sensing tip. Thermal expansion and contraction of distance between fiber end and mirror alters interference between light reflected from those two surfaces, thereby giving interferometric indication of temperatures.

  12. Building polymer fiber optic network

    NASA Astrophysics Data System (ADS)

    Bienias, P.; Bereś-Pawlik, E.

    2015-09-01

    The paper describes an investigation of transmission in LAN with using polymer optical fiber (POF). There were used two kinds of POF, step index plastic optical fiber (SI-POF) and graded index plastic optical fiber (GI-POF). Furthermore, the paper include a comparison between SI-POF and GI-POF and possibilities of using them. For the project's needs, new type of couplers has been designed and built, optimization has been performed to obtain the best parameters for designed couplers. Additionally, the coupler has been built from the same material, which GI-POF - PMMA is made of. Moreover, CWDM (Coarse Wavelength Division Multiplexing) transmissions is investigated to improve the network capacity.

  13. Octave-band tunable optical vortex parametric oscillator.

    PubMed

    Abulikemu, Aizitiaili; Yusufu, Taximaiti; Mamuti, Roukuya; Araki, Shungo; Miyamoto, Katsuhiko; Omatsu, Takashige

    2016-07-11

    We developed an octave-band tunable optical vortex laser based on a 532 nm optical vortex pumped optical parametric oscillator with a simple linear-cavity configuration by employing cascaded non-critical phase-matching LiB3O5 crystals. The optical vortex output was tunable from 735 to 1903 nm. For a pump energy of 9 mJ, an optical vortex pulse energy of 0.24-2.36 mJ was obtained, corresponding to an optical-optical efficiency of 0.3-26%. PMID:27410798

  14. Extreme prepulse contrast utilizing cascaded-optical parametric amplification

    SciTech Connect

    Jovanovic, I; Haefner, C; Wattellier, B; Barty, C J

    2006-06-15

    It has been shown recently that an optical parametric chirped-pulse amplifier can be easily reconfigured into a cascaded-optical parametric amplifier (COPA), enabling complete prepulse removal and optical switching with a window defined by the pump pulse duration. We have demonstrated instrument-limited measurement of the COPA prepulse contrast >1.4 x 10{sup 11} using 30-mJ pulses. The COPA technique is applicable to all energy ranges and pulse durations. A convenient millijoule-scale implementation of this technique is presented using a single, large-aspect-ratio quasi-phase-matched nonlinear crystal.

  15. Fiber-optic currents measurements

    SciTech Connect

    Forman, P.R.; Looney, L.D.; Tabaka, L.J.

    1993-01-01

    Polarization maintaining pigtailed laser diodes have greatly increased the ease with which fiber-optic sensors for Faraday current measurements on large pulsed experiments can be deployed. 670, 830, and 1300 nm units are readily available. Such diode lasers can easily be mounted in an RF shielded box along with the simple electronics and batteries to power them. Our units measure 16.5 [times] 8 [times] 6 cm. and have a single external control; an on off switch. They use two 1.5 volt C'' cell batteries. By using an LT1073 chip in the electronics the batteries are an energy source rather than a voltage source. These units can provide 100 mA drive to a LT015MD laser diode so that 1 mW of 830 nm fight exits the fiber pigtail for up to 23 hours with no detectable droop in power. For the sensor element twisted single mode low birefringence fibers are wrapped around the region of interest. The fiber pigtail is fused to the sensor section so changes in alignment are avoided. The light exiting the fiber sensor section is immediately analyzed by a compact, 3 [times] 3.5 [times] 5 cm, bulk optical unit which outputs quadrature optical signals into two multimode fibers leading to detectors in a screen room. The system is thus completely free of ground loops and is as immune to noise as the screen room. These sensors have the usual advantages claimed for them and the all dielectric feature was the original reason for their use on our experiments. The ease of deployment however is not usually cited. On our Pegasus II experiment the need arose for a total current measurement at the main header of the capacitor banks. A single turn of optical fiber was easily strung in a 6.4 m diameter circle and attached to laser and analyzer in a few hours.

  16. Fiber-optic currents measurements

    SciTech Connect

    Forman, P.R.; Looney, L.D.; Tabaka, L.J.

    1993-03-01

    Polarization maintaining pigtailed laser diodes have greatly increased the ease with which fiber-optic sensors for Faraday current measurements on large pulsed experiments can be deployed. 670, 830, and 1300 nm units are readily available. Such diode lasers can easily be mounted in an RF shielded box along with the simple electronics and batteries to power them. Our units measure 16.5 {times} 8 {times} 6 cm. and have a single external control; an on off switch. They use two 1.5 volt ``C`` cell batteries. By using an LT1073 chip in the electronics the batteries are an energy source rather than a voltage source. These units can provide 100 mA drive to a LT015MD laser diode so that 1 mW of 830 nm fight exits the fiber pigtail for up to 23 hours with no detectable droop in power. For the sensor element twisted single mode low birefringence fibers are wrapped around the region of interest. The fiber pigtail is fused to the sensor section so changes in alignment are avoided. The light exiting the fiber sensor section is immediately analyzed by a compact, 3 {times} 3.5 {times} 5 cm, bulk optical unit which outputs quadrature optical signals into two multimode fibers leading to detectors in a screen room. The system is thus completely free of ground loops and is as immune to noise as the screen room. These sensors have the usual advantages claimed for them and the all dielectric feature was the original reason for their use on our experiments. The ease of deployment however is not usually cited. On our Pegasus II experiment the need arose for a total current measurement at the main header of the capacitor banks. A single turn of optical fiber was easily strung in a 6.4 m diameter circle and attached to laser and analyzer in a few hours.

  17. Design of Fiber Optic Sensors for Measuring Hydrodynamic Parameters

    NASA Technical Reports Server (NTRS)

    Lyons, Donald R.; Quiett, Carramah; Griffin, DeVon (Technical Monitor)

    2001-01-01

    The science of optical hydrodynamics involves relating the optical properties to the fluid dynamic properties of a hydrodynamic system. Fiber-optic sensors are being designed for measuring the hydrodynamic parameters of various systems. As a flowing fluid makes an encounter with a flat surface, it forms a boundary layer near this surface. The region between the boundary layer and the flat plate contains information about parameters such as viscosity, compressibility, pressure, density, and velocity. An analytical model has been developed for examining the hydrodynamic parameters near the surface of a fiber-optic sensor. An analysis of the conservation of momentum, the continuity equation and the Navier-Stokes equation for compressible flow were used to develop expressions for the velocity and the density as a function of the distance along the flow and above the surface. When examining the flow near the surface, these expressions are used to estimate the sensitivity required to perform direct optical measurements and to derive the shear force for indirect optical measurements. The derivation of this result permits the incorporation of better design parameters for other fiber-based sensors. Future work includes analyzing the optical parametric designs of fiber-optic sensors, modeling sensors to utilize the parameters for hydrodynamics and applying different mixtures of hydrodynamic flow. Finally, the fabrication of fiber-optic sensors for hydrodynamic flow applications of the type described in this presentation could enhance aerospace, submarine, and medical technology.

  18. Optically powered fiber networks.

    PubMed

    Röger, M; Böttger, G; Dreschmann, M; Klamouris, C; Huebner, M; Bett, A W; Becker, J; Freude, W; Leuthold, J

    2008-12-22

    Optically powered networks are demonstrated. Heterogeneous subscribers having widely varying needs with respect to power and band-width can be effectively controlled and optically supplied by a central of-fice. The success of the scheme relies both on power-efficient innovative hardware and on a novel low-energy medium access control protocol. We demonstrate a sensor network with subscribers consuming less than 1 microW average power, and an optically powered high-speed video link transmitting data at a bitrate of 100 Mbit/s. PMID:19104615

  19. Strain sensing using optical fibers

    NASA Technical Reports Server (NTRS)

    Houghton, Richard; Hiles, Steven

    1994-01-01

    The main source of attenuation which will be studied is the optical fiber's sensitivity to bending at radii that are much larger than the radius of the fiber. This type of environmental attenuation causes losses that are a function of the severity of the bend. The average attenuation caused by bending varies exponentially with the bend radius. There are many different fibers, sources, and testing equipment available. This thesis describes tests that were performed to evaluate the variables that effect bending related attenuation and will discuss the consistency of the results. Descriptions and comparisons will be made between single mode and multimode fibers as well as instrumentation comparisons between detection equipment. Detailed analysis of the effects of the whispering gallery mode will be performed along with theorized methods for characterization of these modes.

  20. Applications of fiber optics in physical protection

    SciTech Connect

    Buckle, T.H.

    1994-03-01

    The purpose of this NUREG is to provide technical information useful for the development of fiber-optic communications and intrusion detection subsystems relevant to physical protection. There are major sections on fiber-optic technology and applications. Other topics include fiber-optic system components and systems engineering. This document also contains a glossary, a list of standards and specifications, and a list of fiber-optic equipment vendors.

  1. Embedding Optical Fibers In Cast Metal Parts

    NASA Technical Reports Server (NTRS)

    Gibler, William N.; Atkins, Robert A.; Lee, Chung E.; Taylor, Henry F.

    1995-01-01

    Use of metal strain reliefs eliminates breakage of fibers during casting process. Technique for embedding fused silica optical fibers in cast metal parts devised. Optical fiber embedded in flange, fitting, or wall of vacuum or pressure chamber, to provide hermetically sealed feedthrough for optical transmission of measurement or control signals. Another example, optical-fiber temperature sensor embedded in metal structural component to measure strain or temperature inside component.

  2. High pressure fiber optic sensor system

    DOEpatents

    Guida, Renato; Xia, Hua; Lee, Boon K; Dekate, Sachin N

    2013-11-26

    The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

  3. Sealed fiber-optic bundle feedthrough

    DOEpatents

    Tanner, Carol E.

    2002-01-01

    A sealed fiber-optic bundle feedthrough by which a multitude of fiber-optic elements may be passed through an opening or port in a wall or structure separating two environments at different pressures or temperatures while maintaining the desired pressure or temperature in each environment. The feedthrough comprises a rigid sleeve of suitable material, a bundle of individual optical fibers, and a resin-based sealing material that bonds the individual optical fibers to each other and to the rigid sleeve.

  4. Fiber Optics: Deregulate and Deploy.

    ERIC Educational Resources Information Center

    Suwinski, Jan H.

    1993-01-01

    Describes fiber optic technology, explains its use in education and commercial settings, and recommends regulations and legislation that will speed its use to create broadband information networks. Topics discussed include distance learning; interactive video; costs; and the roles of policy makers, lawmakers, public advocacy groups, and consumers.…

  5. Adjustable Optical-Fiber Attenuator

    NASA Technical Reports Server (NTRS)

    Buzzetti, Mike F.

    1994-01-01

    Adjustable fiber-optic attenuator utilizes bending loss to reduce strength of light transmitted along it. Attenuator functions without introducing measurable back-reflection or insertion loss. Relatively insensitive to vibration and changes in temperature. Potential applications include cable television, telephone networks, other signal-distribution networks, and laboratory instrumentation.

  6. Image-rotating, 4-mirror, ring optical parametric oscillator

    DOEpatents

    Smith, Arlee V.; Armstrong, Darrell J.

    2004-08-10

    A device for optical parametric amplification utilizing four mirrors oriented in a nonplanar configuration where the optical plane formed by two of the mirrors is orthogonal to the optical plane formed by the other two mirrors and with the ratio of lengths of the laser beam paths approximately constant regardless of the scale of the device. With a cavity length of less than approximately 110 mm, a conversion efficiency of greater than 45% can be achieved.

  7. Optical parametric amplification with a bandwidth exceeding an octave

    SciTech Connect

    Orlov, Sergei N; Polivanov, Yurii N; Pestryakov, Efim V

    2004-05-31

    The possibility of using various schemes of broadband optical parametric amplifiers (OPAs) for amplifying a supercontinuum with the spectral bandwidth exceeding an octave is analysed. Spectral gain profiles are calculated for some specific OPAs employing promising and available nonlinear optical crystals. The realisation of OPAs with spectral bandwidths exceeding an octave in the spectral region from the near-UV to the mid-IR is demonstrated by specific examples. (nonlinear optical phenomena)

  8. Fiber optic hardware for transport aircraft

    NASA Astrophysics Data System (ADS)

    White, John A.

    Fiber Optic Technology is being developed for aircraft and offers benefits in system performance and manufacturing cost reduction. Thr fiber optic systems have high bandwidths that exceeds all of the new aircraft design requirements and exceptional electromagnetic interference (EMI) immunity. Additionally, fiber optic systems have been installed in production aircraft proving design feasiblity.

  9. Fiber optic hardware for transport aircraft

    NASA Astrophysics Data System (ADS)

    White, John A.

    1994-10-01

    Aircraft manufacturers are developing fiber optic technology to exploit the benefits in system performance and manufacturing cost reduction. The fiber optic systems have high bandwidths and exceptional Electromagnetic Interference immunity that exceeds all new aircraft design requirements. Additionally, aircraft manufacturers have shown production readiness of fiber optic systems and design feasibility.

  10. Hybrid Fiber-Optic/CCD Chip

    NASA Technical Reports Server (NTRS)

    Goss, W. C.; Janesick, J. R.

    1985-01-01

    Low noise and linearity of charge-coupled devices (CCD's) combined with optical waveguide components in hybrid, integrated chip package. Concept used to measure laser flux in fiber-gyro application using sensing fibers that range from several to several tens of kilometers in length. Potential applications include optical delay measurement and linear detector of light flux emanating from fiber-optic waveguides.