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Early Posting

Accepted papers to appear in an upcoming issue

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Articles 1 to 20 of 82 Next Page >>


Design and optimization of an adaptive optics system for HiLASE high-average-power multi-slab laser

  • Jan Pilar, Ondrej Slezak, Pawel Sikocinski, Martin Divoky, Magdalena Sawicka, Stefano Bonora, Antonio Lucianetti, and Tomas Mocek
  • received 12/03/2013; accepted 04/17/2014; posted 04/17/2014; Doc. ID 202253
  • [full text: PDF (588) KB)]
  • Abstract: We report numerical and experimental results obtained with an optical setup that simulates the heating and cooling processes expected in a multi-slab high-average-power laser head. We tested the performance of an adaptive optics system consisting of a photo-controlled deformable mirror and a Shack-Hartmann wavefront sensor for effective correction of the generated wavefront aberrations. The performance of the adaptive optics system is characterized for different layouts of the actuator array and for different configurations of the heating beams.

Keywords (OCIS):

  • (010.7350) Atmospheric and oceanic optics : Wave-front sensing
  • (140.0140) Lasers and laser optics : Lasers and laser optics
  • (140.3280) Lasers and laser optics : Laser amplifiers
  • (110.1080) Imaging systems : Active or adaptive optics

Silver nanowire composite thin films as transparent electrodes for Cu(In,Ga)Se2/ZnS thin film solar cells

  • XiaoHui Tan, Yu Chen, and Ye-Xiang Liu
  • received 02/14/2014; accepted 04/16/2014; posted 04/17/2014; Doc. ID 206181
  • [full text: PDF (1519) KB)]
  • Abstract: Solution processed silver nanowire-indium tin oxide nanoparticle (AgNW-ITONP) composite thin films were successfully applied as the transparent electrodes for Cu(In,Ga)Se2 (CIGS) thin film solar cells with ZnS buffer layers. Properties of the AgNW-ITONP thin film and its effects on performance of CIGS/ZnS thin film solar cells were studied. Compared with the traditional sputtered ITO electrodes, the AgNW-ITONP thin films show comparable optical transmittance and electrical conductivity. Furthermore, the AgNW-ITONP thin film causes no physical damage to the adjacent surface layer and does not need high temperature annealing, which makes it very suitable to use as transparent conductive layers for heat or sputtering damage-sensitive optoelectronic devices. By using AgNW-ITONP electrodes, the required thickness of the ZnS buffer layers for CIGS thin film solar cells was greatly decreased.

Keywords (OCIS):

  • (160.0160) Materials : Materials
  • (310.3840) Thin films : Materials and process characterization
  • (310.4925) Thin films : Other properties (stress, chemical, etc.)

High-repetition-rate and short-pulse-width electro-optical cavity-dumped YVO4/Nd:GdVO4 laser

  • Yufei Ma, XuDong Li, Yu Xin, Renpeng Yan, Rongwei Fan, Jiang bo Peng, Xinrui Xu, Yunchang Bai, and Rui Sun
  • received 03/11/2014; accepted 04/15/2014; posted 04/17/2014; Doc. ID 208081
  • [full text: PDF (1668) KB)]
  • Abstract: In this letter, an electro-optical cavity-dumped 1.06 μm laser using novel YVO4/Nd:GdVO4 composite crystal under 808 nm diode-laser pumping was reported. Theoretical calculations showed that the temperature distribution in YVO4/Nd:GdVO4 crystal was lower than that in GdVO4/Nd:GdVO4 and Nd:GdVO4 crystals under the same conditions. A constant 3.8±0.3 ns pulse width was obtained and the repetition rate could reach up to 50 kHz with a maximum average output power of 5.6 W and slope efficiency of 40.7%, corresponding to a peak power of 31.1 kW.

Keywords (OCIS):

  • (140.3480) Lasers and laser optics : Lasers, diode-pumped
  • (140.3540) Lasers and laser optics : Lasers, Q-switched
  • (140.3580) Lasers and laser optics : Lasers, solid-state

Analytic study of traveling-wave velocity variation in line-focusing schemes for plasma X-ray lasers

  • Fei Jia, Felix Staub, Michael Siegrist, and Jurg Balmer
  • received 01/22/2014; accepted 04/15/2014; posted 04/17/2014; Doc. ID 205086
  • [full text: PDF (670) KB)]
  • Abstract: Efficient amplification of coherent short-wavelength pulses along a plasma gain column requires traveling-wave excitation with the sweep velocity matched to the signal group velocity. Through simulations incorporating the gain dynamics of the system we show that the group velocity is not constant but monotonously increases along the line focus due to strong saturation. We demonstrate a line-focusing configuration that results in traveling wave excitation with the sweep velocity well matched to the spatially varying group velocity. Moreover, we show through numerical simulations that the improved velocity matching yields a significant improvement in signal amplification.

Keywords (OCIS):

  • (080.2740) Geometric optics : Geometric optical design
  • (140.3280) Lasers and laser optics : Laser amplifiers
  • (140.7240) Lasers and laser optics : UV, EUV, and X-ray lasers

Circularly polarized light with high degree of circularity and low azimuthal error sensitivity

  • Jose Luis Vilas, Eusebio Bernabeu Martinez, Luis Miguel Sanchez-Brea, and Rafael Espinosa-Luna
  • received 01/30/2014; accepted 04/15/2014; posted 04/15/2014; Doc. ID 205744
  • [full text: PDF (742) KB)]
  • Abstract: Abstract We analyze how to obtain circular polarized light with a high polarization degree and a high stability using a system composed by two waveplates. The configurations studied involve half and quarter waveplates. We show how the high polarization degree is achieved using a λ/2+λ/4 configuration. However the highest stability under small variations in the azimuths of the waveplates is obtained employing a λ/4+λ/2 configuration. Analytical calculus are particularized for quartz and MgF₂ waveplates are presented.

Keywords (OCIS):

  • (160.1190) Materials : Anisotropic optical materials
  • (220.4830) Optical design and fabrication : Systems design
  • (260.0260) Physical optics : Physical optics
  • (260.1440) Physical optics : Birefringence
  • (260.5430) Physical optics : Polarization

A simple far-field radiative thermal rectifier using Fabry-Pérot cavities based infrared selective emitters

  • E. NEFZAOUI, J. Drevillon, Y. Ezzahri, and K. Joulain
  • received 02/04/2014; accepted 04/15/2014; posted 04/15/2014; Doc. ID 205934
  • [full text: PDF (1021) KB)]
  • Abstract: We present a thermal rectification device concept based on far-field radiative exchange between two selective emitters. Rectification is achieved due to a large contrast between the two selective emitters thermo-optical properties. A simple device constituted by two Fabry-Pérot cavities made of metallic (Au) and semiconductor (Si and HDSi) thin films is proposed. This device is the first rectifier based on photonic structures.It shows a rectification ratio increasing with temperature up to 19% for a temperature difference ΔT = 370 K. Presented results might be useful for energy conversion devices, smart radiative coolers / insulators engineering and thermal logical circuits development.

Keywords (OCIS):

  • (050.2230) Diffraction and gratings : Fabry-Perot
  • (160.6840) Materials : Thermo-optical materials
  • (290.6815) Scattering : Thermal emission
  • (010.5620) Atmospheric and oceanic optics : Radiative transfer

Design of resonant cavity structure for efficient room temperature operation of single photon avalanche photodiodes

  • Mahdi Zavvari, Kambiz Abedi, and Mohammad Karimi
  • received 02/10/2014; accepted 04/14/2014; posted 04/15/2014; Doc. ID 206174
  • [full text: PDF (657) KB)]
  • Abstract: A novel design of single photon avalanche photodiode (SPAD) is proposed based on resonant cavity (RC) structure and its performance is studied. In the proposed structure, InAlAs/InGaAs distributed Bragg reflectors (DBR) are employed as top and bottom mirrors and the quantum efficiency (QE) of absorption region is calculated for absorption region considering the effect of RC. Results show that using 12 periods of DBRs as bottom reflector without incorporation of top mirror can enhance the QE to about 90% at room temperatures. For this RC-enhanced SPAD, a single photon quantum efficiency (SPQE) is obtained about 0.35 at T=300K. For temperatures lower than T=260K, SPQE is about 1. Results show that although the RC doesn’t affect the dark current, however for a given SPQE the dark count rate is lower for RC-SPAD.

Keywords (OCIS):

  • (040.3060) Detectors : Infrared
  • (230.1480) Optical devices : Bragg reflectors
  • (040.1345) Detectors : Avalanche photodiodes (APDs)

Portable multispectral imaging system based on light-emitting diodes for spectral recovery from 370 to 1630 nm

  • Jorge Herrera-Ramírez, Meritxell Vilaseca, and Jaume Pujol
  • received 02/13/2014; accepted 04/14/2014; posted 04/15/2014; Doc. ID 206391
  • [full text: PDF (2287) KB)]
  • Abstract: To expand and investigate the potential of spectral imaging, we developed a portable multispectral system using light-emitting diodes. This system recovers spectral information from the ultraviolet to the near infrared over a large area using two different image sensors synchronized with 23 bands of illumination. The system was assessed for spectral reconstruction through simulations and experimental measurements by means of two methods of spectral reconstruction and three different evaluation metrics. The results over a Macbeth color checker chart and other samples, including pigments usually employed in art paintings, are compared and discussed. The portable multispectral system using light-emitting diodes constitutes a cost-effective and versatile method for spectral imaging.

Keywords (OCIS):

  • (110.0110) Imaging systems : Imaging systems
  • (120.4820) Instrumentation, measurement, and metrology : Optical systems
  • (230.3670) Optical devices : Light-emitting diodes
  • (110.4234) Imaging systems : Multispectral and hyperspectral imaging

Novel calibration method for structured light system with an out-of-focus projector

  • Beiwen Li, Nikolaus Karpinsky, and Song Zhang
  • received 02/13/2014; accepted 04/14/2014; posted 04/15/2014; Doc. ID 206416
  • [full text: PDF (3179) KB)]
  • Abstract: A structured-light system with binary defocusing technique has potential to have more extensive application due to its high speeds, gamma calibration free and no rigid synchronization requirement between the camera and projector. However, the existing calibration methods fail to achieve high accuracy for a structured light system with an out-of-focus projector. This paper proposes a method that can accurately calibrate a structured light system even when the projector is not in focus, making it possible for high-accuracy and high-speed measurement with the binary defocusing method. Experiments demonstrate that a root-mean-square (rms) error of 77 $\mu$m can be achieved with a calibration volume of $150(H)\times 250(W)\times 200(D) mm^3$

Keywords (OCIS):

  • (100.2650) Image processing : Fringe analysis
  • (120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
  • (120.5050) Instrumentation, measurement, and metrology : Phase measurement

SPM and XPM nonlinear effects in the plasmonic directional couplers, considering the ponderomotive metal nonlinearity

  • N. Nozhat and N. Granpayeh
  • received 01/06/2014; accepted 04/14/2014; posted 04/17/2014; Doc. ID 204173
  • [full text: PDF (550) KB)]
  • Abstract: In this paper, the plasmonic directional coupler (PDC) with 90º waveguide bends has been numerically analyzed by the finite-difference time-domain (FDTD) method, considering the nonlinear response of metal due to the ponderomotive force. It has been shown that the required switching power of the PDC is 0.05% of that of the case that only the dielectric is nonlinear and the nonlinearity of metal is neglected. Also, the cross-phase modulation nonlinear effect has been investigated and the power for switching is decreased significantly compared to the one with the self-phase modulation effect.

Keywords (OCIS):

  • (060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
  • (190.3270) Nonlinear optics : Kerr effect
  • (240.6680) Optics at surfaces : Surface plasmons
  • (130.4815) Integrated optics : Optical switching devices
  • (250.5403) Optoelectronics : Plasmonics

Coherent characteristics of the solid-state lasers with Corner Cube

  • Yong CHENG, Xu Liu, Liu yang, Chao-yong Tan, Xia Chen, Meng-zhen Zhu, Chao-wei Mi, and Bin Sun
  • received 12/30/2013; accepted 04/13/2014; posted 04/17/2014; Doc. ID 203923
  • [full text: PDF (1264) KB)]
  • Abstract: Corner cube was firstly theoretically and experimentally proved to be a peculiar coherent combination element by the author, which can contribute to improve the laser far-field energy focalization when it is used as a retro-reflecting mirror in the solid state lasers. Furthermore the differences between the coherent characteristics of the lasers with corner cube resonator (CCR) and F-P resonator were investigated respectively. Theoretical calculation and numerical simulation have proved that the symmetric outputs of the CCR laser are coherent and the adjacent outputs are partially coherent. Based on these special coherent characteristics, a new laser coherent combining structure in which a corner cube was utilized as the terminal mirror was proposed and experimentally investigated. In our experiment, the far-field power distribution measured of the laser array coherent combing is good agreement with the theoretical calculation. This novel coherent characteristics of corner cube may be important for the applications in the solid-state lasers and the laser coherent combining systems, and it may be one of the develop trends and future research directions for CCR lasers.

Keywords (OCIS):

  • (030.1640) Coherence and statistical optics : Coherence
  • (140.3290) Lasers and laser optics : Laser arrays
  • (140.3580) Lasers and laser optics : Lasers, solid-state

Design of an Omni-directional Optical Antenna of UV Communication

  • Xuebin Zhang, Yi Tang, Heqing Huang, Lijun Zhang, and Tingzhu Bai
  • received 01/03/2014; accepted 04/12/2014; posted 04/15/2014; Doc. ID 203359
  • [full text: PDF (497) KB)]
  • Abstract: In this paper, an omni-directional large field optical antenna structure for ultraviolet (UV) communication is proposed and demonstrated. Theoretical analyze shows it’s suitable for short-range UV communication. Simulation indicates that the optical gain is 32.06, and the system has a good spot uniformity, incident angle of incident ray satisfy the requirement of the interference filter(±10°). Outdoor experiments show that the Angle of FOV is about ±20°~±80° and the SNR increased 31dB compared with bare tube, validated that it is useful in free-space UV communication.

Keywords (OCIS):

  • (060.4510) Fiber optics and optical communications : Optical communications
  • (120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
  • (220.0220) Optical design and fabrication : Optical design and fabrication

Investigation of pitch and angle in the gradual-triangle Lenticular lens for point-blank LED fog lamp

  • Hsi-Chao Chen and Chi-Hao Yang
  • received 03/12/2014; accepted 04/11/2014; posted 04/15/2014; Doc. ID 208004
  • [full text: PDF (4056) KB)]
  • Abstract: The effects of different pitch and angle of gradual-triangle Lenticular lens for the point-blank LED fog lamp was investigated under the standard of ECE R19. The novel LED fog lamp was assembled of point-blank LED light source, parabolic reflector and a gradual-triangle Lenticular lens. A light tracing analysis was used for the design of the gradual-triangle Lenticular lens. The pitch, which varied from 1 to 6 mm, and the apex angle, which changed from 5 to 32 degrees, were both investigated in regard to the gradual-triangle Lenticular lens. The optimum pitch was 5mm, and the efficiency of the lamp system and Lenticular lens could reach 93% and 98.1% by simulation, respectively. The results of experiment had over 94% similar to that of simulation by normalized cross correlation (NCC) for the light intensity. © 2014 Optical Society of America

Keywords (OCIS):

  • (220.0220) Optical design and fabrication : Optical design and fabrication
  • (220.4830) Optical design and fabrication : Systems design
  • (230.3670) Optical devices : Light-emitting diodes
  • (220.2945) Optical design and fabrication : Illumination design

A modified dwell time optimization model and its applications in subaperture polishing

  • Zhichao Dong, Haobo cheng, and Honyuen Tam
  • received 03/12/2014; accepted 04/11/2014; posted 04/15/2014; Doc. ID 208062
  • [full text: PDF (4565) KB)]
  • Abstract: The optimization of dwell time is an important procedure in deterministic subaperture polishing. We present a modified optimization model of dwell time by iterative and numerical method, assisted by extended surface form and tool path for suppressing the edge effect. Compared with discrete convolution and linear equation models, the proposed model has essential compatibility to arbitrary tool paths, multiple tool influence functions (TIFs) in one optimization and asymmetric TIFs. The emulational fabrication of a Ф200mm workpiece by the proposed model yields a smooth, continuous and nonnegative dwell time map with a root-mean-square (RMS) convergence rate of 99.6%, and the optimization cost much less time. By the proposed model, influences of TIF size and path interval to convergence rate and polishing time are optimized respectively for typical low and middle spatial frequency errors. Results show that (i) the TIF size is nonlinear inversely proportional to convergence rate and polishing time. A TIF size of ~1/7 the workpiece size is preferred; (ii) the polishing time is less sensitive to path interval, but increasing the interval markedly reduces the convergence rate. A path interval of ~1/8-1/10 of the TIF size is deemed to be appropriate. The proposed model is deployed on a JR-1800 and MRF-180 machine. Figuring Results of Φ920mm Zerodur paraboloid and Φ100mm Zerodur plane by them yield RMS of 0.016λ and 0.013λ (λ=632.8nm) respectively, thereby validate the feasibility of proposed dwell time model used for subaperture polishing.

Keywords (OCIS):

  • (220.4610) Optical design and fabrication : Optical fabrication
  • (220.5450) Optical design and fabrication : Polishing
  • (240.5450) Optics at surfaces : Polishing

Rugate filters used in slit lamp delivery to improve color rendering of illumination for retinal photocoagulation

  • Yi Li, Jiao Chen, Hai Feng, Hao Chen, and Qin Wang
  • received 02/20/2014; accepted 04/11/2014; posted 04/15/2014; Doc. ID 206842
  • [full text: PDF (2602) KB)]
  • Abstract: Laser filter and color filter used in slit lamp delivery have been developed by rugate approach to improve color rendition of illumination for retinal photocoagulation. The double-notch laser filter is designed according to the required laser lines and incident angle. Based on the transmission spectrum of double-notch laser filter and the spectral power distribution (SPD) of the light source of slit lamp, a scanning search algorithm is applied to find the optimal transmission spectrum of multi-notch color filter for the best color rendition index of illumination. An open-source software is used to design the refractive index profile of all the rugate filters which are deposited by the reactive pulse magnetron sputtering. The SPD of slit lamp delivery which will use the deposited double-notch laser filter and multi-notch color filter is also calculated to demonstrate that the color rendition property of illumination can be improved remarkably, thus making fundus observation and retinal laser photocoagulation more reliable and efficient.

Keywords (OCIS):

  • (310.1620) Thin films : Interference coatings
  • (310.1860) Thin films : Deposition and fabrication
  • (330.1715) Vision, color, and visual optics : Color, rendering and metamerism

On the Residual Dispersion Compensation Over S + C + L + U Wavelength Bands Using Highly Birefringent Octagonal Photonic Crystal Fiber

  • M. Samiul Habib, Redwan Ahmad, Md. Selim Habib, and M. Imran Hasan
  • received 12/18/2013; accepted 04/11/2014; posted 04/15/2014; Doc. ID 203170
  • [full text: PDF (506) KB)]
  • Abstract: An octagonal photonic crystal fiber (O-PCF) with elliptical shape in the centre core is numerically investigated for residual dispersion compensation in the wavelength range of 1460 – 1675 nm. The designed fiber exhibits flattened negative dispersion over S + C + L + U wavelength bands and average dispersion of – 465.5 ps/(nm.km) with absolute dispersion variation of 10.5 ps/(nm.km). Besides the proposed PCF shows a high birefringence of 2.68×10-2 at the operating wavelength 1550 nm which meet the requirement of high birefringence. Moreover, variation of two air-holes in the first ring up to 5% ensures average dispersion of – 491.5 ps/(nm.km) with dispersion variation of 13 ps/(nm.km) and birefringence reaches up to 3×10-2. Furthermore, to evaluate the sensitivity of the fiber dispersion properties, ±5% variation in the optimum parameters is studied.

Keywords (OCIS):

  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (060.2330) Fiber optics and optical communications : Fiber optics communications

Laser frequency stability transfer using a fiber-based interferometer

  • Z. Wang, J. Zhang, S Wang, K. Miao, and L. Wang
  • received 02/10/2014; accepted 04/11/2014; posted 04/17/2014; Doc. ID 206219
  • [full text: PDF (528) KB)]
  • Abstract: We have demonstrated a novel method for laser frequency stabilization using a fiber-based Young's interferometer. An 858nm external cavity diode laser is stabilized to within 1e-8 from 10s to 10000s referenced to a Rubidium stabilized 780nm DFB diode laser using the interferometer as a frequency stability transferring link. The system is simple to built and can link any two laser wavelengths within the fiber operating range.

Keywords (OCIS):

  • (040.1520) Detectors : CCD, charge-coupled device
  • (120.3180) Instrumentation, measurement, and metrology : Interferometry
  • (140.3425) Lasers and laser optics : Laser stabilization

Development of an All-optical Temperature Insensitive Non-pendulum Type Tilt Sensor Employing Fiber Bragg Gratings

  • R. Aneesh, Sunil Khijwania, and Pathi Munendhar
  • received 02/12/2014; accepted 04/10/2014; posted 04/15/2014; Doc. ID 206316
  • [full text: PDF (522) KB)]
  • Abstract: A novel design strategy for the development of an all-optical, temperature insensitive, non-pendulum type, tilt sensor employing Fiber Bragg Gratings (FBGs) is proposed and experimentally demonstrated. Being non-pendulum type, there is no possibility of any inherent friction and the limiting effects at mechanical joints. Sensor is observed to be capable of resolving magnitude as well as the direction of inclination from horizontal strategically more effectively and without any inherent instability. This is reflected in a relatively better resolution (better than 0.004o), a better accuracy (~ ±0.05o) and lesser maximum discrepancy (~ ±0.001 nm) during the forward as well as the reverse tilt. Sensitivity of the proposed sensor, theoretically proportional to the half of the mass employed in the sensor design, is observed to be 0.012 nm/o with a comparatively smaller mass. Importantly, sensor response is characterized with a very high degree of reversibility and repeatability over the designed/observed dynamic range.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Optical behavior and structural property of CuAlS2 and AgAlS2 wide-band-gap chalcopyrites

  • Ching-Hwa Ho and Chia-Chi Pan
  • received 02/27/2014; accepted 04/10/2014; posted 04/15/2014; Doc. ID 207250
  • [full text: PDF (1134) KB)]
  • Abstract: Single crystals of CuAlS2 and AgAlS2 were grown by chemical vapor transport method using ICl3 as the transport. The as-grown CuAlS2 crystals reveal transparent and light-green color. Most of them possess a well-defined (112) surface. The AgAlS2 crystals essentially show transparent and white color in vacuum. As the AgAlS2 was put into atmosphere, the crystal surface gradually darkened and brownish because the surface reaction with humidity or hydrogen gas. After a long-term chemical reaction process, the AgAlS2 will transform into a AgAlO2 oxide with yellow color. From X-ray diffraction measurements, both CuAlS2 and AgAlS2 as-grown crystals show single phase and isostructural to a chalcopyrite structure. The (112) face is more preferable for the formation of the chalcopyrite crystals. The energies of interband transitions of the CuAlS2 and AgAlS2 were determined accurately by thermoreflectance measurements in a wide energy range of 2-6 eV. The valence-band electronic structures of CuAlS2 and AgAlS2 have been detailed characterized using polarized-thermoreflectance measurements in the temperature range between 30 and 300 K. The band-edge transitions belonging to the E|| and E⊥ polarizations have been respectively identified. The band edge of AgAlS2 is near 3.2 eV while that of CuAlS2 is about 3.5 eV. On the basis of the experimental analyses, optical and sensing behaviors of the chalcopyrite crystals have been realized.

Keywords (OCIS):

  • (160.4760) Materials : Optical properties
  • (160.6000) Materials : Semiconductor materials
  • (260.5430) Physical optics : Polarization
  • (300.6470) Spectroscopy : Spectroscopy, semiconductors

Improved algorithm based on a fiber loop: applications for optical water vapor sensor

  • C Zhu, J. Chang, P. Wang, Q. Wang, W. Wei, C. Tian, and S. Zhang
  • received 12/17/2013; accepted 04/09/2014; posted 04/15/2014; Doc. ID 203135
  • [full text: PDF (543) KB)]
  • Abstract: An improved algorithm based on a fiber loop optical structure is proposed for measurement of water vapor concentration. Compared to the traditional algorithm, the intrinsic loss of optical devices in the loop no longer needs to be accurately measured, but instead be directly eliminated by normalization. The insertion loss requirement of the optical devices could also be greatly reduced because the calculation of water vapor concentration can be achieved by only two pulses. In addition, a background absorption problem caused by the water vapor existing inside internal end-face gaps of optical components can also be solved. The gas concentration can be directly calculated by using the Beer-Lambert law. By using the improved algorithm, the mean absolute error is reduced from 861 ppm to 29.4 ppm.

Keywords (OCIS):

  • (010.7340) Atmospheric and oceanic optics : Water
  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (300.1030) Spectroscopy : Absorption
  • (150.5495) Machine vision : Process monitoring and control

Articles 1 to 20 of 82 Next Page >>

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