http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
점광원 출력광의 이동 결과를 물체파로 사용하는 홀로그램의 기록과 3차원 상의 재생
이승걸,Marhic M. E. 한국광학회 1995 한국광학회지 Vol.6 No.4
The new method of recording and reconstructing a synthetic object, which was called as scannedobject holography (SOH), was proposed and its feasibility was demonstrated theoretically and experimentally. The hologram was recorded by interfering the fixed reference beam with spherical waves emitting from a moving point source, whose trajectory determined the shape of the synthetic object to be recorded. The end face of an optical fiber and the output from a pulsed laser were utilized in order to implement a moving point source experimentally. tally. 본 논문에서는 가상적인 물체를 기록하고 재생하는 새로운 홀로그램 기록방법인 scanned-object holography를 제안하였으며 그 가능성을 이론과 실험을 통해 증명하였다. 이 방법에서는 점광원으로부터 방출되는 구면파의 이동결과와 정지된 기준파를 연속적으로 간섭시킴으로서 점광원의 이동 경로로 표현되는 가상적인 물체를 기록할 수 있었다. 이때 점광원을 실험적으로 구현하기 위해 광섬유 출력단과 펄스형 레이저를 사용하였다.
연속발진 도파형 이산화탄소 레이저의 이득계수 및 포화출력 측정
이승걸,김현태,박대윤 한국광학회 1990 한국광학회지 Vol.1 No.2
Two ZnSe loss plates were installed in the resonator of waveguide CO2 laser which consisted of Pyrex capillary tube in order to change the internal loss. By rotating the loss plates, the output variations with the internalloss was measured on various discharge conditions. The variations could be explained by the Rigrod theory. and the saturation power and the unsaturated gain coefficient were determined by fitting of the experimental results. It was found that the saturation power increased while the unsaturated gain coefficient reduced as the discharge current or the gas flow rate increased.reased. 내경이 2.1mm인 Pyrex 모세관을 사용하여 길이가 150mm인 도파형 이산화탄소 레이저를 제작하였으며, 공진기내에 임의의 손실을 가할 수 있는 ZnSe 손실판을 설치하여 공진기의 내부손실에 따른 출력변화를 여러 방전조건에 대해 측정하였다. 본 실험에 Rigrod 이론을 적용하여 내부손실에 따른 출력변화를 예측했으며 실험치로부터 포화출력 및 불포화 이득계수를 구할 수 있었다. 방전전류와 혼합기체의 유입률이 증가함에 따라 포화출력은 증가하며, 불포화 이득계수는 감소하는 경향을 볼 수 있었다.
이승걸,박대서,오범환,박세근,이일항 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.6
We propose a new photonic crystal (PhC) wavelength demultiplexer based on self-imaging in multimode interference (MMI) section and on the reflecting filter characteristics of PhC defects inserted into the MMI section. Because PhC defects with adequate bandgap act as a dichroic mirror, a signal with one wavelength is reflected from the PhC defects, but another signal with a different wavelength is transmitted. Introduction of PhC defects makes the wavelength demultiplexer much shorter because there is no need to consider the common beat length for two signals of different wavelengths. The proposed device was analyzed and optimized using the plane-wave expansion model and the finite-dierence time-domain method. The multimode section of the optimally designed device had a size of 10.3 × 3.2 μm2 and its extinction ratios were -21.7 dB and -16.3 dB for signals of 1.3 and 1.55 μm, respectively.