• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1363-1375
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• 2000

The electromagnetic scattering characteristics by a periodic strip grating on a grounded dielectric slab for TM polarization case are examined from the viewpoints of both the reflection grating and the leaky wave antenna problems. Numerical results far two kinds of Bragg blazing (resonance type and non-resonance type) phenomena are given and some discussions on the properties(complex propagation constants, scattering characteristics, and distributions of strip current density) are presented. The comparison of the Bragg blazing phenomena between TM and TE polarization cases are also given in detail.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.594-606
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• 1999

The electromagnetic scattering characteristics by a periodic strip grating on a grounded dielectric slab for TE polarization case is examined from the viewpoints of both the reflection grating and the leaky wave antenna problems. Numerical results for two kinds of Bragg blazing (resonance type and non-resonance type) phenomena are given and some discussions on the properties such as complex propagation constants, scattering characteristics, and distributions of strip current density are presented.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1445-1447
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• 2001

We have investigated about the grating formation of the $a-Se_{75}-Ge_{25}$ chalcogenide thin films. In this study, holographic gratings have been formed by using He-Ne laser(632.8nm) with different polarization states(linear, circular polarization). The diffraction efficiency was obtained by +1st order intensity of the diffracted beam. We have obtained maximum efficiency for Ag-doped thin film. It is observed the difference of the diffraction efficiency with polarization states. S:S-polarized state is shown high efficiency than the other polarization.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.2
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• pp.238-252
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• 1998

Diffraction anomalies in the periodic strip grating over a grounded dielectric layer are investigated for the plane wave incidence case of both arbitrary(oblique) incidence angle and arbitrary polarization by use of the spectral domain method combined with the sampling theorem. Some numerical results for the Bragg and Off-Bragg blazing phenomena for the cases of arbitrary incidence angle and polarization as well as TE and TM polarization are presented along with discussions on those phenomena.

• Current Optics and Photonics
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• v.1 no.2
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• pp.150-156
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• 2017

A diffraction limited optical system for head mounted displays (HMDs) was designed. This optical system consists of four modules, including 1:5 mm and 5:30 mm beam expanders, polarization grating-polarization conversion system (PG-PCS) and refractive/diffractive projection optical module. The PG-PCS module transforms the unpolarized Gaussian beam to a linearly polarized beam and it simultaneously homogenizes the spatial intensity profile. The optical projector module has a $30^{\circ}$ field of view, a 22 mm eye relief, and a 10 mm exit pupil diameter with a compact structure. Common acrylic materials were utilized in the optical design process; therefore, the final optical system was lightweight. The whole optical system is suitable for a 0.7 inch liquid crystal on silicon microdisplay (LCOS) with HDTV resolution ($1920{\times}1080$) and $8.0{\mu}m$ pixel pitch.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.617-620
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• 1999

In this study, the polarization e(fecal and the birefringence effect of amorphous germanium (a-Ge) thin films were investigated by using linearly polarized He-Ne laser beam. The a-7e thin films were deposited on the quarts substrate by plasma enhanced chemical vapor deposition (PECVD) and thermal vacuum evaporation In order to obtain the optimum grating arrays, inorganci resists such as Si$_3$N$_4$ and a-Se$_{75}$ Ge$_{25}$ , were prepared with the optimized thickness by Monte Carlo (MC) simulation. As the results of MC simulation, the thickness ofa-Se$_{75}$ Ge$_{25}$ resist was determined with Z$_{min}$ of 360$\AA$ . The resists were exposed to Ga$^{+}$-FIB with accelerating energies of 50 keV, developed by wet etching, and a-Ge thin film was etched by reactive ion-etching (RIE). Finally, we were obtained grating arrays which grating width and linewidth are 0.8${\mu}{\textrm}{m}$, respectively and we studied the polarization and birefringence effect in transmission grating array made of high refractive amorphous material, and the applicability as waveplates and polarizers in optical device.e.e.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.10
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• pp.1820-1822
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• 2007

In this paper we fabricated a fiber device composed of cascaded long-period fiber gratings between which a birefringent erbium-doped fiber was inserted and proposed its application as a polarization-controlled interleaved signal gating fiber device. Because the core and cladding modes of the fabricated fiber device have polarization-dependent phase difference due to the birefringence of the erbium-doped fiber, its interference spectrum can be modulated by varying the input polarization.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.107-107
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• 2010

In this study, we have investigated the holographic grating formation on Ag-doped amorphous chalcogenide AsGeSeS thin films with Ag thickness. Ag/AsGeSeS thin films with the incident laser beam wavelength for the improvement of the polarization diffraction grating efficiency. Holographic gratings have been formed using Diode Pumped Solid State laser (DPSS, 532.0nm) under [P:P] polarized the intensity polarization holography. The diffraction efficiency was obtained by +1st order intensity. The result is shown that the diffraction efficiency of Ag/AsGeSeS double layer thin film for the Ag thickness, the maximum grating diffraction efficiency using 60nm Ag layer is 0.96%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.133-136
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• 2001

In this paper, we investigated the diffraction efficiency of polarization holography using by amorphous $Ag/As_{40}Ge_{10}Se_{15}S_{35}$ multi-layer thin films by He-Ne laser. Multi-layer structures were formed by alternating a layer of meta1(Ag) and chalcogenide( $Ag/As_{40}Ge_{10}Se_{15}S_{35}$ ). The holographic grating in these thin flims has been formed using a linealy polarized He-Ne laser light (633nm). The diffraction efficiency was investigated the two sample of $Ag/As_{40}Ge_{10}Se_{15}S_{35}-7$ layers and $Ag/As_{40}Ge_{10}Se_{15}S_{35}-15$ layers. As the results, we found that the diffraction efficiency of $Ag/As_{40}Ge_{10}Se_{15}S_{35}-7$ layers and $Ag/As_{40}Ge_{10}Se_{15}S_{35}-15$ layers were 1.7% and 2.5% respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.133-136
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• 2001

In this paper, we investigated the diffraction efficiency of polarization holography using by amorphous Ag/As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/ multi-layer thin films by He-Ne laser. Multi-layer structures were formed by alternating a layer of metal(Ag) and chalcogenide(As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/). The holographic grating in these thin films has been formed using a lineally polarized He-Ne laser light (633nm). The diffraction efficiency was investigated the two sample of Ag/As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/-7 layers and Ag/As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/-15 layers. As the results, we found that the diffraction efficiency of Ag/As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/-7 layers and Ag/As$\sub$40/Ge$\sub$10/Se$\sub$15/S$\sub$35/-15 layers were 1.7% and 2.5% respectively