• Journal of the Optical Society of Korea
• /
• 제16권1호
• /
• pp.17-21
• /
• 2012

A surface-normal input/output volume holographic grating coupler (VHGC) operating at 1550nm wavelength region by using a $10{\mu}m$-thick DuPont photopolymer film is designed and fabricated. The angular and wavelength responses of the input/output VHGC are investigated in order to validate applicability of this device in integrated optics and optical communications. The effect of incident-beam position on the output reflectance to determine optimum condition for input coupling is also presented. The fabricated input/output VHGC exhibited an angular selectivity of ${\sim}0.027^{\circ}$, a wavelength selectivity of ~0.8 nm, and an output peak reflectance of 34.13%.

• 한국광학회:학술대회논문집
• /
• 한국광학회 2007년도 하계학술발표회 논문집
• /
• pp.279-280
• /
• 2007

• 한국광학회:학술대회논문집
• /
• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
• /
• pp.272-273
• /
• 2002

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제55권10호
• /
• pp.461-466
• /
• 2006

In the present work, we investigated the photodissolution and photodiffusion effect on the interface of Ag/chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film by measuring the absorption coefficient, the optical density, the resistance change of Ag layer. It was found that the photodissolutioniphotodiffution ratio depends on the magnitude of photon energy absorbed in the chalcogenide thin film and the depth of photodiffution was proportional to the square root of the exposed time. Also, we have investigated the holographic grating formation with P-polarization states on chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film and $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film. Holographic gratings have been formed using He-Ne laser (632.8 nm) which have a smaller energy than the optical energy gap, $E_g\;_{opt}$ of the film, i. e., an exposure of sub-bandgap light $(h{\upsilon} under P-polarization. As the results, we found that the diffraction efficiency on $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film was more higher than that on single $As_{40}Ge_{10}Se_{15}S_{35}$ thin film. Also, we obtained that the maximum diffraction efficiency was 0.27 %, 1,000 sec on $As_{40}Ge_{10}Se_{15}S_{35}\;(1{\mu}m)/Ag$ (10 nm) double layer structure thin film by (P: P) polarized recording beam. It will offer lots of information for the photodoping mechanism and the analyses of chalcogenide thin films.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 하계학술대회 논문집
• /
• pp.299-302
• /
• 2000

In this study, we have made the large holographic surface relief gratings on amorphous chalcogenide $As_{40}$$Ge_{10}$$Se_{15}$$S_{35}$ films by two beam interference using a He-Ne laser(632.8nm) light. The film thickness was about 0.6$\mu\textrm{m}$, we could magnify beam size by using beam expander. We made use $90^{\circ}$ holder which was made of reflection mirror and sample. Formed the surface relief structures were investigated using optical microscope. The diffraction efficiency was obtained by measuring +lst order intensity. In addition we investigated grating formation and diffraction efficiency as a function of polarization states which is linear or circular polarization. The results indicate that the grating was formed by linear polarized beam is better clear than that by circular polarized beam.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1988년도 춘계학술대회 논문집
• /
• pp.20-23
• /
• 1988

Effect of light irradiation on evaporated chalcogenide glass films of an As-Se-S-Ge system has been studied. Utiling this characteristics diffraction grating of the amorphous film was obtained. Parameters such as film thickness, composition, and exporsure time influencing the diffraction efficiency were also studied. The maximum value of the diffraction efficiency achieved was 4.6% in an $As_{75}Se_{15}S_{35}-Ge_{10}$ film.

• 한국전기전자재료학회논문지
• /
• 제30권5호
• /
• pp.325-330
• /
• 2017

We fabricated 1-D and 2-D diffraction gratings of SiOx anti-reflection (AR) film grown on a quartz substrate and integrated them into a c-Si photovoltaic (PV) submodule. The light-trapping effect of the resulting submodules was studied in terms of the oblique optical incident angle, ${\theta}_i$. As the ${\theta}_i$ increased, solar conversion efficiency, ${\eta}$, was improved as expected by the increased optical transmission caused by the grating. For ${\theta}_i{\leq}30^{\circ}$, the relative solar conversion efficiency, ${\Delta}{\eta}$, of a 1-D SiOx (t=300 nm) grating, compared to that of a flat SiOx AR-coated integrated PV submodule, was improved very little, with a small variation of within 2%, but increased markedly for ${\theta}_i{\geq}40^{\circ}$. We observed a change of ${\Delta}{\eta}$ as large as 10.7% and 9.5% for the SiOx grating of period t=800 nm and 1200 nm, respectively. For a 2-D SiOx (t=300 nm) grating integrated PV submodule, however, the optical trapping behavior was similar in terms of ${\theta}_i$ but its variation was small, within ${\pm}1.0%$.

• 한국광학회:학술대회논문집
• /
• 한국광학회 2007년도 하계학술발표회 논문집
• /
• pp.299-300
• /
• 2007

• 한국통신학회논문지
• /
• 제17권12호
• /
• pp.1353-1361
• /
• 1992

가볍고 박막이며 자유공간 상호연결이 가능한 홀로그래피 광학소자 (HOE)를 제작하였다. 특히 광연결 및 다중영상처리를 위해서는 고효율이어야 하며 같은 파워의 스폿빔이 형성되어야 한다. 2차원 2진 위상구조를 갖는 위상격자를 찾기위해 modified Newton방식을 기초로 컴퓨터 시뮬레이션하여 비선형 방정식의 해를 구하였다. 플로터를 이용하여 원화를 그린다음 축소하여 마이크로 필름에 정보를 옮겼다. 마이크로 필름과 은염 홀로그램 필름을 접촉복사시켜 위상형 회절격자를 만들어 $5{\times}5$ 다중 스폿빔을 형성시켰다. 중앙 0차 빔을 제외하고는 균일한 세기를 가졌으며 표백처리된 홀로그래피 광학소자는 고효율을 얻을 수 있었다.

• 한국광학회지
• /
• 제19권4호
• /
• pp.315-319
• /
• 2008

열광학 장주기 격자를 이용한 노치 필터의 파워 소모를 이론적으로 살펴 보았다. 여기서 열광학 장주기 격자는 주기적인 히터들과 패드들로 구성된 히터 배열에 의해 유발된다. 히터 배열에서 소모되는 파워는 열광학 장주기 격자를 유발하는 줄(joule) 열로 전환되기 때문에, 그 파워를 조절함으로써 노치 필터의 특성을 동적으로 제어할 수 있다. 적절한 결합 효율을 얻기 위해 히터 배열에 가하는 파워는 히터 배열의 인자들에 의존하는데, 이 인자들은 히터의 폭과 길이, 패드의 폭, 그리고 히터 배열을 구성하는 금속 박막의 두께이다. 이 인자들이 파워 소모에 미치는 영향을 이론적으로 해석하는 근사적인 방법을 설명하고, 설명한 방법을 사용하여 인자들의 변화에 따른 파워 소모의 변화를 해석한다. 해석 결과로부터 파워 소모를 줄이기 위해 필요한 인자 선택의 기준을 도출한다.