• Korean Journal of Optics and Photonics
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• v.10 no.1
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• pp.32-39
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• 1999

In this paper, we made CGH patterns that had continuous amplitude distribution binary coded patterns with two different methods, and analyzed those patterns by using LCSLM (liquid crystal spatial light modulator). The error diffusion algorithm and direct quantization method were used as the binarization methods. The parameters of overall average brightness, mean square error, and diffraction efficiency were used in the comparison of reconstruction characteristics. The LCSLM which we used in this experiment was a binary reflective ferroelectric liquid crystal spatial light modulator addressed electrically with 256$\times$256 pixels, 87% fill factor and 15$\mu$m pixel pitch.

• Current Optics and Photonics
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• v.3 no.3
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• pp.215-219
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• 2019

Chromatic aberrations induced by Risley prisms made of a single material can be substantially compensated using a liquid crystal spatial light modulator while still keeping the prism pairs compact, simple and lightweight. A ${\pm}10^{\circ}$ optical scanning imaging system with ${\pm}2^{\circ}$instantaneous field based on LC-SLM correction is designed as an example. The ultimate simulation results show that this kind of scheme is an effective way of improving imaging performance dynamically across the full field of scanning.

• Journal of Information Display
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• v.3 no.3
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• pp.24-29
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• 2002

Liquid Crystal Spatial Light Modulators (LC-SLMs) provide many interesting applications in laser optics and opto-el ectronic systems, in addition to displays. Among them, three topics developed at Thales Research & Technology are reviewed: wavefront correction for laser beam control, microwave processing in radar systems and holography for TN-LCDs viewing angle compensation.

• Journal of the Optical Society of Korea
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• v.15 no.4
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• pp.345-351
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• 2011

We present a novel approach to the holographic three-dimensional display using a liquid crystal shutter for binocular display applications. One of the difficult problems in implementing a binocular holographic three-dimensional display is the extremely narrow viewing angle. This problem is attributed to the spatial light modulator pixel number which restricts the maximum spatial bandwidth of the spatial light modulator. In our proposed method, a beam splitter and liquid crystal shutter are used to present two holograms of a three-dimensional scene to the corresponding eyes. The combination of holographic display and liquid crystal shutter can overcome the problem of the extremely narrow viewing angle, presenting threedimensional images to both eyes with correct accommodation depth cues.

• Current Optics and Photonics
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• v.5 no.3
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• pp.261-269
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• 2021

Binary-phase complex spatial light modulators (BP-C-SLMs) are proposed and simulated. This study shows that bottom-top mirror-symmetrical uniaxial systems between two orthogonal polarizers allow one to construct BP-C-SLMs. BP-C-SLMs double the information-handling capacity per pixel, compared to the conventional amplitude-only spatial light modulators (A-SLMs), as well as being simply implemented with a single spatial light modulator (SLM), rather than a combination of an A-SLM and a binary-phase SLMs. Under limited conditions, BP-C-SLMs can control only the amplitude in single-phase space, and act as A-SLMs.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.939-942
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• 2002

The optically addressed and electrically addressed spatial phase only light modulators without pixelized structures have been developed. A sufficient phase modulation capability and a high diffraction efficiency of these devices are useful for practical applications.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.443-448
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• 2012

A polarimetric experimental method was developed to determine the Jones matrix elements of transparent optical materials without sign ambiguity. A set of polarization dependent transmittance data of the samples was measured with polarizer - sample - analyzer system and another set of data was measured with polarizer - sample - quarter-wave plate - analyzer. Two data sets were compared and mathematically analyzed to obtain the correct signs of the elements of the matrix. The Jones matrix elements of a quarter-wave plate were determined to check the validity of the method. The experimentally obtained matrix elements of the quarter-wave plate were consistent with the theoretical expectations. The same method was applied to obtain the Jones matrix elements of a twisted nematic liquid crystal panel.

• Korean Journal of Optics and Photonics
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• v.13 no.5
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• pp.408-413
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• 2002

We demonstrated a polarization dependent type 2$\times$2 optical switch, using a binary reflection type SLM. Reflection type FLC was used as a half wave retardation plate. Two inputs were controlled by each SLM for the desired output direction. In conclusion, in the "1" state the average optical loss was 6.6 ㏈, and in the "0" state the average optical loss was 14.6 ㏈, and measured the switching speed as 75 $mutextrm{s}$. By using this method, a polarization dependent type 2$\times$2 optical switch can be demonstrated and the possibility of a 4-port WDM optical switch also verified.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.285-288
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• 2002

We propose the use of synchronously moving micro-optics (lenslet arrays) for image pickup and display in three-dimensional integral imaging to overcome the upper resolution limit imposed by the Nyquist sampling theorem. With the proposed technique, we present an all-optical three-dimensional integral imaging projector. An optically addressed spatial light modulator is used, which potentially provides better image resolution than the conventional CCD and liquid crystal display pair. We present experimental results using a liquid crystal light valve.

• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.659-665
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• 2008

We demonstrate experimentally that the method of Two-pupil optical scanning technique with PAL-spatial light modulator is capable of performing real-time joint transform correlation(JTC) optical system. Optical addressing is achieved by the use of a photosensitive layer of $\alpha$ - Si which controls the electric field across the liquid crystal The demonstrated technique is based on two-pupil optical heterodyne scanning. The method is independent of a spatial light modulator (SLM) in the Fourier plane. We develop the theory of the technique and evaluate a performance of the method by experimentally estimating the correlation between the target image and the reference image.