• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1986.10a
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• pp.194-197
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• 1986

In this paper, for the curvature correction on the scanning plane in laser scanning system, aberration correction method using holographic optical element is suggested. Holoens is selected as a type of holographic zone plate which has aberration correction property. And hologram recording condition is analyzed to find fo property. This hololens is implemented by computer-generated hologram technique. Laser scanning system is organized using desinged hololens and scanning properties of this system are investigated. Using this method optical system structure in laser scanning system can be simplified satisfying both scan linearity and field flatness.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.958-961
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• 1999

A new image encoding and identification scheme is proposed for security verification by using CGH(computer generated hologram), random phase mask, and correlation technique. The encrypted image, which is attached to the security product, is made by multiplying QPH(quadratic phase hologram) using SA(simulated annealing) algorithm with a random phase function. The random phase function plays a role of key when the encrypted image is decrypted. The encrypted image could be optically recovered by 2-f system and automatically verified for personal identification. Simulation results show the proposed method cand be used for the reconstruction and the recognition of the encrypted. Image.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.380-383
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• 2010

본 논문에서는 다시점 카메라를 기반으로 홀로그램 영상을 재생하는 기술을 제안한다. 본 논문에서는 다시점 카메라를 이용해 획득한 발레영상을 사용하여 깊이정보에서 관심객체만을 추출하였다. 추출한 관심객체의 홀로그램 복원화질을 향상시키기 위해 본 논문에서 제안한 함수를 적용하였다. 필터링된 관심객체의 깊이정보와 CGH(Computer-Generated Hologram) 기법을 이용하여 디지털 홀로그램을 생성하였다. 이 디지털 홀로그램을 PC 시뮬레이션을 통해 홀로그램 영상으로 복원한 후 제안한 기법의 적용결과를 주관적인 화질평가를 통해 검증하였다.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.410-413
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• 1988

In this paper, the real-time optical associative memory using multiple hologram which is generated with two angular multiplexed reference beams and Fourier transformed object beam in the $BaTiO_{3}$ crystal based on DFWM mechanism. When one image is recorded in the $BaTiO_{3}$ crystal, complete image can be recalled by 9 % partial input of the stored original image without any additional thresholding and optical feedback process. As an experimental result of multiple Fourier hologram which is recorded with two binary images, OHCHAS and PARKHK, we can obtain complete image recalled by 1/6 partial input of the stored image.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.163-164
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• 2007

위폐 판별을 위한 홀로그램 광학 검사 시스템을 제안한다. 이 시스템은 홀로그램의 표준패턴을 생성을 CGH(Computer Generated Hologram)방법에 근거한 주파수 변환을 적용하고, 조명각도에 따라 홀로그램 이미지를 정확하게 획득하여 특성에 적합한 홀로그램 표준패턴을 생성하게 된다. 생성한 표준패턴과 실제 영상과의 패턴매칭을 위해 패턴매칭알고리즘을 적용하여 위폐를 판별하는 검사시스템이다.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1375-1378
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• 2009

In this paper, a new method to efficiently generate the holographic news ticker in holographic 3DTV or 3-D movies using N-LUT method is proposed. The proposed method is largely consisted of five steps: construction of the LUT for each character, extraction of characters in news ticker, generation and shift of the CGH pattern for news ticker using the LUT, composition of hologram pattern for 3-D video and news ticker and reconstruct the holographic 3D video with news ticker. From some simulation results confirmed the feasibility of the proposed method in fast generation of CGH patterns for holographic news ticker.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.310-311
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• 2007

다중패턴 홀로그램을 위한 자동 검사 시스템을 제안한다. 시스템 하드웨어는 조명계, 카메라 그리고 영상처리부로 구성된다. UV LED를 사용하는 다양한 조명은 다른 위치에 놓여 각 위치에서의 이미지 패턴을 획득한다. 시스템 소프트웨어는 전처리, 패턴 생성, 패턴매칭으로 구성된다. 획득한 입력 홀로그램 영상은 패턴매칭 알고리즘에 의해 표준 패턴과 비교한다. 입력 홀로그램의 위치 오차 보정을 위해, 다른 위치에서의 홀로그램 표준 패턴은 온라인상에서 생성되어야만 한다. 본 논문은 표준 패턴의 생성을 위해 CGH(Computer Generated Hologram)방법에 근거한 주파수 변환을 적용한다. 한국지폐의 홀로그램을 위한 실험 결과는 제안한 시스템의 유용성을 증명한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.07a
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• pp.323-324
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• 2020

논문에서는 3D 체적형 모델을 이용하여 홀로그램에 랜덤 위상 효과를 주는 방법을 제안한다. CGH(Computer Generated Hologram)에서 랜덤 위상의 추가는 실제 촬영하여 획득한 홀로그램에서 물체 표면의 난반사에 대한 영향을 고려한 것이다. 이 랜덤 위상은 생성한 홀로그램의 광 시야각 확장 효과가 있다. 하지만 이것은 랜덤으로 발생하기 때문에 홀로그램 시퀀스를 생성할 때 같은 객체 표면에 대해서 고정된 효과를 줄 수 없다. 본 논문에서는 CGH를 진행할 때 물체의 고유한 랜덤 위상 추가를 위해 3D 체적형 모델을 사용하는 방법을 제안한다.

• Korean Journal of Optics and Photonics
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• v.15 no.1
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• pp.39-45
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• 2004

A computer simulation about removal of the 0-th order diffraction is achieved by using numerical reconstruction in digital holography and the Fourier transform method. A light intensity distribution hologram is generated through numerical calculation of the interference pattern. Additionally a phase hologram without the 0-th order diffraction is generated. The removal function for elimination of the 0-the order diffraction is introduced and the numerical reconstructions with several conditions for the removal of the 0-th order diffraction and the production of high quality numerically reconstructed images are tested and compared. The removal function is proven to be more effective at the suppression of the 0-th order diffraction compared with the DC suppression method.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.6
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• pp.149-155
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• 1996

In this paper, we designed binary phase grating with SA (simulated annealing) algorithm for image generation, and used LCTV(liquid crystal television) as phase modulator. We generated optical image using LCTV which controlled by personal computer in real time. Many parameters in SA algorithm are determined by average deviation of the cost function, not experimental method. It was confirmed that the LCTV could be used as a phase modulator through mach-zehnder interferometering experiment. The various optical images are generated in real itme by fourier transforming of the phase gratings on LCTV which is controlled by personal computer and they can be used for optical interconnection in a neural network and addressing information in a volume hologram etc.