• Transactions of the Society of Information Storage Systems
• /
• v.2 no.3
• /
• pp.189-195
• /
• 2006

Bragg detuning effect if, one of the serious problems if the photopolymer is used for the recording material of holography memories. And the critical reasons of that are known as the bulk refractive index change and shrinkage of recording material. However, the trials for analyzing the effect are mainly on the K-sphere and biased on the transmission hologram. So, we approached Bragg detuning effect numerically and applied the method to the transmission holograms and the reflection holograms all together. We simulated it with MATLAB. As a result, the bulk refractive index change causes+Bragg detuning effect on the transmission holograms and the reflection holograms. But the shrinkage leads to+Bragg detuning effect on the transmission hologram and-Bragg detuning effect on the reflective hologram. Compared to experimental result, the bulk refractive index change(${\fallingdotseq}4{\times}10^{-4}$) and the ratio of shrinkage to the thickness of the material(${\fallingdotseq}1.67{\times}10^{-3}$) could be matched with Bragg detuning effect on the transmission hologram and the reflection hologram.

• International Journal of Internet, Broadcasting and Communication
• /
• v.12 no.4
• /
• pp.128-136
• /
• 2020

In this paper, we presented a simple hologram recording set for learners to broaden their program choices and experience holographic techniques with lifelong education programs. In order to obtain quality 3D images, the quality of light sources and recording mediums, which are the main elements of hologram recording, must be good. In addition, due to the characteristics of the hologram, the ambient vibrations shall be minimized for accurate interference pattern recording. The simple hologram recording set presented in this paper has not significantly restricted in space and location, and anyone can easily experience it at a reasonable price compared to the existing hologram production method. Also, it can make two different type of hologram (transmission and reflection) for providing easy access to recording and reconstruction of the hologram. Experiments have shown that holographic manufacturing practices are a very useful way to educate the public on optics and photonics technologies.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.8
• /
• pp.793-798
• /
• 2009

In this paper, the simulation and optimization of SRH (Surface Relief Hologram) masks for printing LCD gate patterns using TIR (Total Internal Reflection) holographic lithography was investigated. A simulation and optimization algorithm based on SDTA (Scalar Diffraction Theory Analysis) method was developed. The accuracy of the algorithm was compared to that of the RCWA (Rigorous Coupled Wave Analysis) method for estimating the Fresnel diffraction pattern of Cr amplitude masks for the given system geometry. In addition, the results from the optimization algorithm were validated experimentally. It was found that one to the most important conditions for the fabrication of SRH masks is to avoid nonlinear shape distortions of the resulting grating. These distortions can be avoided by designing SRH masks with recorded gratings having small aspect ratios of width versus depth. The optimum gap size between the Cr and SRH masks was found using the optimization algorithm. A printed LCD gate pattern with a minimum line width of $1.5{\mu}m$ exposed using the optimized SRH mask was experimentally demonstrated.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 1990.10a
• /
• pp.186-189
• /
• 1990

• Korean Journal of Optics and Photonics
• /
• v.22 no.5
• /
• pp.214-218
• /
• 2011

In this paper we have applied self-reference hologram to DHM (digital holography microscopy) to remove phase aberration. We have constructed an off-axis reflection- type digital holography microscope. We have extracted a low spatial frequency hologram from the conjugated hologram and used it as a reference hologram. Experimentally we show that distortion of image and aberration of phase in a measurement system are removed using the self-reference hologram.

• Korean Journal of Optics and Photonics
• /
• v.18 no.1
• /
• pp.8-13
• /
• 2007

In this paper, we analyze the optical properties of the transmission grating recorded in a reflection-type photopolymer. Recording and reconstruction of the micropattern using a total internal reflection hologram applied to a reflection type photopolymer are studied. The transmission-type photopolymer was shown to have the maximum diffraction efficiency in $40^{\circ}C$ symmetric structure. However, that of reflection type photopolymer was more than 90% at $60{\sim}80^{\circ}$. The line and point patterns with the interval of $1{\mu}m$ are recorded successfully and can be observed when the micro objective lenses with 10 and 100 time magnification are used.

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.74-75
• /
• 2007

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.269-270
• /
• 2007

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.02a
• /
• pp.24-25
• /
• 2007

• Optical Science and Technology
• /
• v.8 no.2
• /
• pp.22-26
• /
• 2004

회절 광학 소자(Diffractive optical element)는 광학 시스템에 있어서 광을 조절하기 위하여 굴절(refraction) 또는 반사(reflection)보다는 주기 구조(periodic structures)에 의한 회절(diffraction)을 이용한 소자라 할 수 있다. DOE의 장점으로는 수차(aberration)가 없는 point-to-point 이미지가 가능하며 광 power를 사용한 평판(flat subface)이 가능하고 비구면과 같은 수차 조절이 가능하다. 단점으로는 HOE(Hologram Optical Element: DOE의 일종)의 수차가 이 구조의 특정 파장에서 나타나고 가시영역의 일정 영역에서 매우 분산적 (dispersive)이다. 또한 상대적으로 시장의 성장에 비하여 찾는 고객의 수가 적다는 점이다.(중략)