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Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

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Early Posting

Accepted papers to appear in an upcoming issue

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January


Non-uniform grid target tessellation method for the design of lens group with rectangular uniform illumination

  • Zhenjie Liu and Feihong Yu
  • received 10/10/2014; accepted 01/19/2015; posted 01/20/2015; Doc. ID 223346
  • [full text: PDF (1318) KB)]
  • Abstract: A non-uniform grid target tessellation method is proposed for designing a lens group with rectangular uniform illumination, a small screen incident angle and high collection efficiency. A collimation lens is first designed to collimate the source rays preliminarily. Secondly, the source collected solid angle is tessellated so that each source ray encompasses the same flux. Thirdly, the source rays are traced to the first surface of lens2. Finally, the non-uniform grid target tessellation iteration is applied to find the integration constraint mapping. The free-form surface constructed with this method can exactly refract the rays to their corresponding target location, and the rectangular uniform illumination is accomplished. To verify the effectiveness of the proposed method, a design example is presented with a rectangular figuration and a high uniformity, the incident angle is smaller than and the collection efficiency reaches 96% with Lambertian point source.

Keywords (OCIS):

  • (220.3620) Optical design and fabrication : Lens system design
  • (220.2945) Optical design and fabrication : Illumination design
  • (080.4298) Geometric optics : Nonimaging optics

Blind spectral deconvolution with Wavelet regularization for Poisson noise

  • Liu Hai, Zhang Tianxu, and Yan Luxin
  • received 10/20/2014; accepted 01/19/2015; posted 01/20/2015; Doc. ID 225257
  • [full text: PDF (463) KB)]
  • Abstract: In this work, we introduce a blind deconvolution approach with Wavelet regularization for the Raman spectrum and total variation (TV) regularization for instrument function. The proposed algorithm can effectively suppress the Poisson noise as well as preserve the spectral structure information. Moreover, the split Bregman method is adopted to solve the proposed model. The comparative results on the simulated and measured Raman spectra show that the Wavelet-based method outperforms the conventional methods. The deconvolution Raman spectrum is more convenient for extracting the spectral feature and interpreting the unknown chemical mixtures.

Keywords (OCIS):

  • (100.3190) Image processing : Inverse problems
  • (170.5660) Medical optics and biotechnology : Raman spectroscopy
  • (300.6320) Spectroscopy : Spectroscopy, high-resolution
  • (060.3510) Fiber optics and optical communications : Lasers, fiber

Limited Magnitude Calculation Method and Optics Detection Performance in Photoelectric Tracking System

  • hanshan li
  • received 12/09/2014; accepted 01/19/2015; posted 01/20/2015; Doc. ID 229400
  • [full text: PDF (408) KB)]
  • Abstract: To improve the tracking performance of the orbital target tracking system, this paper researches limited magnitude calculation method and photoelectric detection performance in photoelectric tracking system, deduces and sets up the calculation model of the limited magnitude of the orbital photoelectric tracking system based on the characteristics of the target luminance, background luminance and CCD noise, analyzes the key factors which affect its photoelectric detection performance, discusses the relation of limited detectable magnitude of the photoelectric detection system with the exposure time of CCD, the threshold of SNR and the dark current of the photoelectric detection system, and gives the calculation function and the change curve of corresponding function parameters. Through the synchronous tracking experiment, the detection performance and limited magnitude calculation function of the target photoelectric tracking system were verified, the results show that within a certain illumination, the longer the exposure time of CCD is, the smaller the dark current of the photoelectric detection system is. The test data and the theory calculation data is in accordance.

Keywords (OCIS):

  • (080.0080) Geometric optics : Geometric optics
  • (080.2740) Geometric optics : Geometric optical design
  • (230.0230) Optical devices : Optical devices
  • (250.0250) Optoelectronics : Optoelectronics

Implicit absolute phase retrieval in digital fringe projection without reference lines

  • William De la Cruz De los Santos and María de Lourdes López García
  • received 08/01/2014; accepted 01/19/2015; posted 01/21/2015; Doc. ID 219985
  • [full text: PDF (1890) KB)]
  • Abstract: Absolute phase retrieval is an important task in many phase shifting profilometry systems. Most methods of the state of the art use the projection of a reference line on the scene or the codification of codewords in the phase domain. In this paper, we propose a novel method based on the generation of constant phase lines. Our method only requires the determination of a strategic pixel on the projector and it is used as the starting point of the unwrapping algorithm. Experimental validation shows that the generated phase lines have higher accuracy than the projected reference lines and can be used to obtain the absolute phase map for disconnected objects.

Keywords (OCIS):

  • (100.5070) Image processing : Phase retrieval
  • (110.6880) Imaging systems : Three-dimensional image acquisition
  • (120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
  • (120.5050) Instrumentation, measurement, and metrology : Phase measurement

300-mm ruling engine producing gratings and echelles under interferometric control in China

  • xiaotian li, yang chao, haili yu, Shanwen Zhang, Shu Feng, Xiangdong Qi, galantu Jiri, and Cui Jicheng
  • received 10/17/2014; accepted 01/19/2015; posted 01/22/2015; Doc. ID 225177
  • [full text: PDF (1635) KB)]
  • Abstract: The designs of a 300-mm ruling engine producing gratings and echelles under interferometric control (CIOMP-2) are presented. A new ruling-tool carriage system and its driving mechanism—which are easy to manufacture—are proposed. A new blank carriage system, controlled by a dual-frequency laser interferometer and a piezoelectric actuator, is designed. The CIOMP-2 ruling engine can now rule grating blanks with dimensions up to 300 mm × 300 mm, and mainly rules gratings with grating constants between 10 and 2400 lines/mm. The wavelength range of CIOMP-2 gratings is from ultraviolet to mid-infrared wavelengths. Experiments show that the new ruling-tool carriage system works well and stability of motion is improved with the help of a flexurehinge structure,and the three-fold standard deviation values of the blank carriage positioning errors are less than ~5 nm. For 600- line/mm gratings (diffraction order m = –1), the scatter intensities and ghosts reach 10–5 of the maximum intensity. The scatter intensities and ghost of gratings ruled with CIOMP-2 are low, and no Rowland ghosts are visible. The gratings ruled by CIOMP-2 have high diffraction efficiency and resolving power. CIOMP-2 can also produce varied-line-space, bend-line, and aberration-reducing gratings and echelles.

Keywords (OCIS):

  • (050.0050) Diffraction and gratings : Diffraction and gratings
  • (070.4790) Fourier optics and signal processing : Spectrum analysis
  • (120.4640) Instrumentation, measurement, and metrology : Optical instruments
  • (120.6200) Instrumentation, measurement, and metrology : Spectrometers and spectroscopic instrumentation
  • (140.0140) Lasers and laser optics : Lasers and laser optics
  • (220.4880) Optical design and fabrication : Optomechanics

Biosensing performance of surface plasmon polariton Bragg gratings

  • Pierre Berini and Kholoud Gazzaz
  • received 12/09/2014; accepted 01/18/2015; posted 01/20/2015; Doc. ID 229194
  • [full text: PDF (727) KB)]
  • Abstract: Surface plasmon biosensors have raised much interest over the past few decades for their potential in biosensing applications. Waveguide Bragg gratings supporting long-range surface plasmon-polaritons, consisting of step-in-width metal stripes embedded in Cytop with an etched microfluifdic channel to expose the sensing surface, are proposed as biosensors. Several designs are investigated to evaluate their bulk and surface sensitivities under wavelength interrogation. Detection limits of ~10-6 RIU and ~8 pg/mm2 are predicted for bulk and surface sensing, respectively, with corresponding figures of merit of ~1000 RIU-1 and ~0.2 nm-1. Third order gratings were found to be good choices because they have essentially the same sensitivity as first order gratings but over a narrower bandwidth and they are easier to fabricate due to their larger pitch.

Keywords (OCIS):

  • (230.7390) Optical devices : Waveguides, planar
  • (240.6680) Optics at surfaces : Surface plasmons
  • (280.1415) Remote sensing and sensors : Biological sensing and sensors
  • (250.5403) Optoelectronics : Plasmonics

Spatiotemporal Difference-of-Gaussians filters for robust infrared small target tracking in various complex scenes

  • Xin Wang, Chen Ning, and Lizhong Xu
  • received 10/21/2014; accepted 01/18/2015; posted 01/20/2015; Doc. ID 225347
  • [full text: PDF (1821) KB)]
  • Abstract: Tracking infrared small target is a vital component of many computer vision applications, including infrared precise guidance, early warning, and infrared remote sensing. Various complicated scenes, however, present significant challenges to the tracking task. To solve this problem, we present a novel three-dimensional spatiotemporal Difference-of-Gaussians filters-based algorithm for tracking small targets in infrared videos of various complex scenes. Firstly, the biologically inspired three-dimensional Difference-of-Gaussians filters are proposed for infrared small target tracking, which are capable of accounting for both spatial and temporal information. Then, based on such filters, an effective and robust tracker is constructed to track the small targets which are spatiotemporally distinguishable from the background clutters. Extensive experiments show that our approach tracks the small targets accurately and robustly in realistic infrared videos of complex backgrounds that present unique difficulty to other approaches.

Keywords (OCIS):

  • (040.1880) Detectors : Detection
  • (040.3060) Detectors : Infrared
  • (100.2000) Image processing : Digital image processing
  • (100.4999) Image processing : Pattern recognition, target tracking

Diffractive optical elements for optical identification

  • Vishal Gandhi, Joni Orava, Hemmo Tuovinen, Janne Laukkanen, Seppo Honkanen, Markku Hauta-Kasari, and Toni Saastamoinen
  • received 11/20/2014; accepted 01/17/2015; posted 01/21/2015; Doc. ID 226837
  • [full text: PDF (1999) KB)]
  • Abstract: We present the design and fabrication of diffractive optical elements (DOEs) for optical identification purposes. Two methods for optical identification are discussed. In this feasibility study, approaches using one and two binary reflective diffraction gratings are demonstrated. The diffraction orders of the grating/gratings are used as a binary code for the optical identification. The gratings are designed using the Iterative Fourier Transform Algorithm (IFTA) for an incoming coherent monochromatic laser beam (633 nm, He-Ne laser). The micro-relief structures are fabricated by a combination of atomic layer deposition (ALD) and electron beam lithography (EBL). The scanning electron microscope (SEM) images show good quality of the diffraction gratings. Optical characterization and measurement results demonstrate the feasibility of the proposed identification methods.

Keywords (OCIS):

  • (050.0050) Diffraction and gratings : Diffraction and gratings
  • (220.0220) Optical design and fabrication : Optical design and fabrication
  • (230.0230) Optical devices : Optical devices
  • (060.4785) Fiber optics and optical communications : Optical security and encryption

Theoretical Research on Slow Light Engineering of Slotted Photonic Crystal Waveguide with Elliptical Holes and Optofluidic Infiltration

  • Yong Zhao, Nan Zhang, and Jin Li
  • received 12/16/2014; accepted 01/16/2015; posted 01/20/2015; Doc. ID 230834
  • [full text: PDF (512) KB)]
  • Abstract: Slow light engineering of slotted photonic crystal waveguide (SPCW) is realized by combining both the benefits of elliptical holes and optofluidic infiltration. By adjusting the refractive indices of optofluidics that infiltrated in the first and second rows of elliptical holes adjacent to slot, slow light can be improved to possess high group index and wide bandwidth at the same time. Considering a criterion of restricting the group index variation within a ±10% range as flat region, the corresponding bandwidths of the flat band can reach to 17.92 nm, 7.2 nm, 3.65 nm, and 1.8 nm around 1550 nm when the group indices are approximately kept at constants of 32, 57, 110, and 2.5, respectively. Besides, the capability to engineer slow light properties after fabrication is interesting to compensate fabrication errors.

Keywords (OCIS):

  • (230.7400) Optical devices : Waveguides, slab
  • (130.5296) Integrated optics : Photonic crystal waveguides

Research of polishing process to control the iron contamination on the magnetorheological finished KDP crystal surface

  • Chen Shaoshan, Shengyi li, Hao Hu, guipeng tie, and Xiaoqiang Peng
  • received 11/21/2014; accepted 01/16/2015; posted 01/20/2015; Doc. ID 228270
  • [full text: PDF (2592) KB)]
  • Abstract: A new non-aqueous and abrasive-free magnetorheological finishing (MRF) method is adopted for processing KDP crystal. MRF polishing is easy to result in the embedding of carbonyl iron (CI) powders; meanwhile, Fe contamination on the KDP crystal surface will affect the laser induced damage threshold (LIDT) seriously. This paper puts forward appropriate MRF polishing process to avoid the embedding. Polishing results show the embedding of CI powders can be avoided by controlling polishing parameters. Furthermore, on the KDP crystal surface, MR fluids residua inevitably exists after polishing and in which the Fe contamination cannot be removed completely by initial ultrasonic cleaning. To solve this problem, a kind of ion beam figuring (IBF) cleaning is introduced to remove the impurity layer. Then the content of Fe element contamination and the depth of impurity elements are measured by Time of Flight Secondary Ion Mass Spectrometry (Tof-sims). The measurement results show that there is no CI powders embedding on the MRF polished surface and no Fe contamination after IBF cleaning, respectively. That verifies the feasibility of MRF polishing-IBF cleaning for processing KDP crystal.

Keywords (OCIS):

  • (140.3390) Lasers and laser optics : Laser materials processing
  • (220.4610) Optical design and fabrication : Optical fabrication
  • (220.5450) Optical design and fabrication : Polishing
  • (240.5450) Optics at surfaces : Polishing

Optical constant of CoFeB thin film measured with interference enhancement method

  • Xinan Liang, Xuewu Xu, Ruitao Zheng, Abel Zhi Ming Lum, and Jinjun Qiu
  • received 10/01/2014; accepted 01/16/2015; posted 01/16/2015; Doc. ID 224013
  • [full text: PDF (3767) KB)]
  • Abstract: Optical constants (n and k) of Co20Fe60B20 (CoFeB) thin films (2~40nm) are measured by using interference enhancement method with spectroscopic ellipsometry in the wavelength range of 270~1600nm. The effects of film thickness, protection layer and annealing process on the optical constant of CoFeB film are investigated. In the range of 40~10nm, both n and k decrease with the decrease of thickness. The protection layer of SiO2 on the CoFeB film is helpful for the precise measurement of the n and k values. The annealing process has less effect on the optical constant of the film with the protection layer as compared to the one without it.

Keywords (OCIS):

  • (120.2130) Instrumentation, measurement, and metrology : Ellipsometry and polarimetry
  • (160.4760) Materials : Optical properties
  • (240.0310) Optics at surfaces : Thin films

Packet Error Rate Analysis of DPIM In Inter-Satellite Optical Communication Systems with Diversified Wavefront Deformation

  • Wanqing Xie, Dayan Wang, and Jin Zhu
  • received 11/19/2014; accepted 01/16/2015; posted 01/16/2015; Doc. ID 227031
  • [full text: PDF (2511) KB)]
  • Abstract: Diversified wavefront deformation is an inevitable phenomenon in inter-satellite optical communication systems which will decrease system performance. In this paper, we investigate the description of wavefront deformation and its influence on the packet error rate (PER) of digital pulse interval modulation (DPIM). With wavelet method, the diversified wavefront deformation can be described by wavelet parameters: coefficient, dilation and shift factors where coefficient factor represents the depth, dilation factor represents the area and shift factor is for location. Based on this, the relationship between PER and wavelet parameters is analyzed from theoretical viewpoint. Numerical results illustrate the validity of theoretical analysis: PER increases with the depth and area, and decreases if location gets farther from the center of optical antenna. In addition for describing diversified deformation, the advantage of wavelet method over Zernike polynomials in computational complexity is shown via numerical example. This work provides a feasible method for the description along with influence analysis of diversified wavefront deformation from practical viewpoint, and will be helpful for the designing of optical systems.

Keywords (OCIS):

  • (010.3310) Atmospheric and oceanic optics : Laser beam transmission
  • (050.1970) Diffraction and gratings : Diffractive optics
  • (060.4510) Fiber optics and optical communications : Optical communications

Gold-film coating assisted femtosecond laser fabrication of large-area, uniform surface micro/nanostructures

  • Xin Li, Pin Feng, Lan Jiang, Wenlong Rong, Kaihu Zhang, and Qiang Cao
  • received 11/06/2014; accepted 01/15/2015; posted 01/16/2015; Doc. ID 226429
  • [full text: PDF (2154) KB)]
  • Abstract: This paper reports a simple, repeatable approach to fabricate large-area, uniform micro/nanostructures by a femtosecond laser. Specially, 20 nm gold films are coated on semiconductor surfaces on which large-area, uniform micro/nanostructures are fabricated. In the case study of silicon, defects and cross-links are significantly reduced in the laser induced surface structures on Au-coated silicon. The good consistency between the scanning lines facilitates the formation of large-area, uniform surface micro/nanostructures. The diffusion of hot electrons in the Au films increases the interfacial carrier densities, which significantly enhances interfacial electron–phonon coupling. High and uniform electron density suppresses the influence of defects on silicon and further makes the coupling field more uniform and thus reduces the impact of laser energy fluctuations, which homogenizes and stabilizes large-area surface micro/nanostructures.

Keywords (OCIS):

  • (320.2250) Ultrafast optics : Femtosecond phenomena
  • (350.3390) Other areas of optics : Laser materials processing
  • (220.4241) Optical design and fabrication : Nanostructure fabrication

Gradient of refractive index (GRIN) effect in photo-thermo-refractive glass

  • Julien Lumeau and Leonid Glebov
  • received 10/22/2014; accepted 01/15/2015; posted 01/16/2015; Doc. ID 225471
  • [full text: PDF (660) KB)]
  • Abstract: Photo-Thermo-Refractive (PTR) glass is a photosensitive multicomponent silicate glass containing photosensitive agents such as cerium and silver. Photo-induced crystalline phase precipitation results in refractive index variations in exposed areas of PTR glass, which has been successfully used for phase hologram recording. Photosensitivity being the result of the partial absorption of the exposing radiation by cerium ions, it results in a gradient of refractive index (GRIN) along the exposure beam propagation. This GRIN is a parasitic effect that deteriorates the parameters of some types of volume Bragg gratings because of the beam deflection they produce. In this paper, the evolution of GRIN is investigated as a function of the dosage of UV-exposure and the thermal treatment duration. We show that GRIN is a deterministic process that can be easily modeled and predicted using basic optics and glass science equations.

Keywords (OCIS):

  • (300.1030) Spectroscopy : Absorption
  • (160.5335) Materials : Photosensitive materials

Side-polished fiber based optical coupler assisted with a fused nano silica film

  • Yunhan Luo, Qingsong Wei, Yue Ma, Jun Zhang, Junbin Fang, Jianhui Yu, Jieyuan Tang, Zhe Chen, Huihui Lu, and Jinbo Yu
  • received 10/24/2014; accepted 01/14/2015; posted 01/16/2015; Doc. ID 225660
  • [full text: PDF (6191) KB)]
  • Abstract: We have proposed and demonstrated a novel method for fabricating fiber coupler by sandwiching a fused nano silica film with a pair of side polished fibers (SPFs). The silica nano-particles (SNPs) deposited on the polished regions of SPFs fuse under hydroxide flame and form an adhesive silica film, which bonds the SPF pairs tightly and matches the refractive index of the fiber cladding. Couplers with various coupling ratios can be available with the SPF-SNP-SPF sandwiching method. The fabricated optical fiber couplers have an excess loss lower than 0.5dB, a wavelength dependence loss less than 0.35dB in the wavelength range of 1520~1620 nm, a polarization dependent loss better than 0.12dB, and also shows immunity to variation of temperature and humidity. Such SPF-SNP-SPF sandwiched optical fiber couplers are large in core diameter, robust in structure, easy to fabricate, and compatible with fiber-optic systems and possesses high potentiality in photonics applications such as all-optical fiber communication.

Keywords (OCIS):

  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (220.0220) Optical design and fabrication : Optical design and fabrication
  • (230.1150) Optical devices : All-optical devices

Slow Light with Large Group Index - Bandwidth Product in Ellipse-Hole Photonic Crystal Waveguides

  • Tao Wang, Xu Han, jian tang, Bo Liu, Boyun Wang, Yu He, and Youjiang Zhu
  • received 11/11/2014; accepted 01/14/2015; posted 01/16/2015; Doc. ID 226711
  • [full text: PDF (2455) KB)]
  • Abstract: In this study, we proposed a new type of slow light photonic crystal waveguide (PCW) structure to achieve slow light with wideband and low dispersion. The waveguide is based on triangular lattice ellipse-hole photonic crystal imposed by simply a selective altering the locations of the holes adjacent to the line defect. Under a constant group index criterion of ±10% variation, when group indices are nearly constants of 54, 69 and 80, their corresponding bandwidths of flat band reach 12.7 nm, 10.0 nm, and 8.6 nm around 1550 nm, respectively. A nearly constant large group index - bandwidth product (GBP) of 0.44 is achieved for all cases. Low dispersion slow light propagation is confirmed by studying the relative temporal pulse-width spreading with the 2D finite-difference time-domain method.

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (230.7370) Optical devices : Waveguides
  • (050.5298) Diffraction and gratings : Photonic crystals

Generation of controllable rotating petal-like modes using composited Dammann vortex gratings

  • Junjie Yu, Changhe Zhou, Wei Jia, Jun Wu, Linwei Zhu, Yancong Lu, Shubin Li, and Changcheng Xiang
  • received 11/17/2014; accepted 01/14/2015; posted 01/16/2015; Doc. ID 226893
  • [full text: PDF (1558) KB)]
  • Abstract: A new type of diffractive optical elements, called composited Dammann vortex gratings (CDVGs), is proposed for generation of multiple equal-energy controllable rotating petal-like modes extra cavity. As an example, it is shown that a petal-like mode is well generated for each nonzero diffraction orders by a binary pure-phase 1×7 CDVG. Mode decomposition is digitally implemented by a programmable spatial light modulator (SLM) and the experimental results show that those generated petal-like patterns are in high mode purity (~90%) for all six different nonzero orders. Also, controllable rotating petal-like modes are demonstrated when the CDVG is digitally implemented by the programmable SLM, which provides a possibility to quantitatively control the rotation rate of this type of optical tweezers. Furthermore, tunable petal-like modes are also demonstrated in experiment by introducing a vortex incident field with different topological charges.

Keywords (OCIS):

  • (050.1950) Diffraction and gratings : Diffraction gratings
  • (230.1950) Optical devices : Diffraction gratings
  • (050.4865) Diffraction and gratings : Optical vortices

A Micro Genetic Optimization Algorithm for Optimal Wavefront Shaping

  • Benjamin Anderson, Hergen Eilers, Ray Gunawidjaja, and Patrick Price
  • received 12/09/2014; accepted 01/14/2015; posted 01/16/2015; Doc. ID 229179
  • [full text: PDF (1127) KB)]
  • Abstract: One of the main limitations of utilizing optimal wavefront shaping in imaging and authentication applications is the slow speed of the optimization algorithms currently being used. To address this problem we develop a micro genetic optimization algorithm ($\mu$GA) for optimal wavefront shaping. We test the abilities of the $\mu$GA and make comparisons to previous algorithms (iterative and simple genetic) by using each algorithm to optimize transmission through an opaque medium. From our experiments we find that the $\mu$GA is faster than both the iterative and simple genetic algorithms and that both genetic algorithms are more resistant to noise and sample decoherence than the iterative algorithm.

Keywords (OCIS):

  • (000.3860) General : Mathematical methods in physics
  • (000.4430) General : Numerical approximation and analysis
  • (010.1080) Atmospheric and oceanic optics : Active or adaptive optics
  • (290.7050) Scattering : Turbid media
  • (110.0113) Imaging systems : Imaging through turbid media

Experimental measurements of the spectral absorption coefficient of pure fused silica optical fibers

  • Travis Moore and Matthew Jones
  • received 10/01/2014; accepted 01/14/2015; posted 01/14/2015; Doc. ID 223842
  • [full text: PDF (446) KB)]
  • Abstract: Knowledge of the spectral absorption coefficient of fused silica optical fibers is important in modeling the heat transfer in the processes and applications in which these fibers are used. An experimental method used to measure the spectral absorption coefficient of optical fibers is presented. Radiative energy from a blackbody radiator set at different temperatures is directed through the optical fibers and into an FTIR spectrometer. Spectral instrument response functions are calculated for different fiber lengths. The ratios of the slopes of the instrument response functions for the different lengths of fibers are used to solve for the spectral absorption coefficient of the fibers. The spectral absorption coefficient of low OH pure fused silica optical fibers is measured between the wavelengths 1.5 and 2.5 µm.

Keywords (OCIS):

  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (060.2400) Fiber optics and optical communications : Fiber properties
  • (300.6300) Spectroscopy : Spectroscopy, Fourier transforms

Predictive capability of average Stokes polarimetry for simulation of phase multilevel elements onto LCoS devices

  • A. Márquez, Francisco Martínez, Sergi Gallego, Manuel Ortuño, Jorge Francés Monllor, Inmaculada Pascual, and Augusto Belendez
  • received 10/01/2014; accepted 01/14/2015; posted 01/14/2015; Doc. ID 224110
  • [full text: PDF (602) KB)]
  • Abstract: Parallel-aligned liquid crystal on silicon (PA-LCoS) microdisplays are especially appealing in a wide range of spatial light modulation applications since they enable phase-only operation. Recently we proposed a novel polarimetric method, based on Stokes polarimetry, enabling the characterization of their linear retardance and the magnitude of their associated phase fluctuations or flicker, exhibited by many LCoS devices. In this work we apply the calibrated values obtained with this technique to show their capability to predict the performance of spatially varying phase multilevel elements displayed onto the PA-LCoS device. Specifically we address a series of multilevel phase blazed gratings. We analyse both their average diffraction efficiency, “static” analysis, and its associated time fluctuation, “dynamic” analysis. Two different electrical configuration files, with different degrees of flicker are applied in order to evaluate the actual influence of flicker on the expected performance of the diffractive optical elements (DOEs) addressed. We obtain a good agreement between simulation and experiment, thus demonstrating the predictive capability of the calibration provided by the average Stokes polarimetric technique. Additionally, it is obtained that for electrical configurations with less than 30º of amplitude for the flicker retardance, they may not influence the performance of the blazed gratings. In general, we demonstrate that the influence of flicker greatly diminishes when the number of quantization levels in the optical element increases.

Keywords (OCIS):

  • (050.1970) Diffraction and gratings : Diffractive optics
  • (120.2040) Instrumentation, measurement, and metrology : Displays
  • (120.5410) Instrumentation, measurement, and metrology : Polarimetry
  • (230.2090) Optical devices : Electro-optical devices
  • (230.3720) Optical devices : Liquid-crystal devices
  • (230.6120) Optical devices : Spatial light modulators

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