• 제목/요약/키워드: Moire fringe

검색결과 51건 처리시간 0.032초

무아레 무늬를 이용한 참 난수 생성 방법 (True Random Number Generation Method by using the Moire Fringe)

  • 강혁;이근호
    • 사물인터넷융복합논문지
    • /
    • 제2권1호
    • /
    • pp.23-27
    • /
    • 2016
  • 빛의 물리적 성질 중의 하나인 파동의 회절 현상을 설명하는 프레넬 회절과 간섭에 의해 생성되는 무아레 무늬가 있다. 본 논문에서는 무아레 무늬에서 생성되어지는 값들을 암호 시스템에서 사용되는 키로, 의사 난수 발생기에서 생성한 난수가 아닌 참난수로 만들어 사용할 수 있음을 제안한다.

코팅원지 및 바인더가 코팅지의 인쇄적성에 미치는 영향 (Effect of Base Paper and Binder on the Printability of Coated Paper)

  • 이용규
    • 한국인쇄학회지
    • /
    • 제15권2호
    • /
    • pp.57-76
    • /
    • 1997
  • A color halftoning is the process of generating halftone images for the different color plans, for example, cyan, magenta, yellow, and black for a offset printing device. A conventional halftone technique, so called AM screening, is simple and easy to implement, but the halftoned dot patterns by using this method is not free for the moire` fringe. Moire` patterns are caused the power spectrum distribution on low spatial frequency domain. To avoid Moire` patterns, the conventional screen require the different screen angles for each color plans. Recently, Ultra-fine and 7 color printing methods are developed to expend the color gamut. In 7 color printing method must be used the halftone technique of random and blue noise characteristic to avoid Moire` fringe.

  • PDF

무아레 프린지 기법 적용 광섬유 센서를 위한 다점 측정 모델의 개발 (Development of Multiplexing Model for Moire-Fringe-Based Fiber Optic Sensor)

  • 김대현;이연관;김천곤
    • 비파괴검사학회지
    • /
    • 제30권1호
    • /
    • pp.36-45
    • /
    • 2010
  • 본 논문에서는 무아레 광섬유 센서의 활용성을 극대화할 수 있는 다점 측정 기술에 대해 연구하였다. 특히 기존의 무아레 광섬유 센서가 갖는 다점 측정 기술의 한계점을 극복하기 위해 반사형 단일 프린지만을 사용한 신개념의 광섬유 센서를 고안하였으며 이를 통해 다점 측정의 방법을 획기적으로 개선할 수 있게 되었다. 또한 기존의 다점 측정 원리들을 조사하여 이를 바탕으로 본 연구에서 개발한 무아레 광섬유 센서에 적용 가능한 네 개의 다점 측정 모델을 제시하였다. 이 모델은 기본적으로 파장 분할 다점 측정법과 시간 분할 다점 측정법에 기초를 두고 설계 되었으며 특별히 프린지 기반 광섬유 센서와 같이 외적 형태의 광섬유 센서에 적용 가능한 모델로 제안하였다. 최종적으로 제안된 다점 측정 모델들을 실험적으로 검증하기 위해 광학 시스템을 실제로 제작하였고 프린지 광섬유 센서에 적용하여 본 연구에서 제안된 다점 측정법의 기능성을 성공적으로 검증하였다.

가슴형상 측정을 위한 PMP Moire 방법 활용 (A Study on the Measurement of the Breast Shape on Living Body by Using a PMP Moire Method)

  • 이가나;육근철;김병미
    • 한국의상디자인학회지
    • /
    • 제11권2호
    • /
    • pp.11-21
    • /
    • 2009
  • Recently, as custom-made demand about female underwear is increased, securing of a various dimension system is urgent, and satisfaction of each customer cannot be heightened with established dimensions. If we could measure shape of a living body with a fast and simple method, the custom-made demand of customers could be satisfied in the underwear as well as a clothing industry by using the method. One of the alternatives is shape measurement of the living body by a Moire fringe method. If we put a grating in front of an object to be measured and illuminate light, a Moire fringe with contour line shape is generated in the object, so we can conveniently measure object shape without touching directly by using the pattern. The Moire fringe and three-dimensional shape of the breast of the living body was acquired by a PMP method using a polygon mirror, and height and bottom width of the breast of the living body were measured by using obtained data in this study. Data of breast shape measurement through a mannequin was collected in a previous step as basic material for measuring the breast shape measurement of the living body. Three women in the twenties were selected as one of methods for measuring breast shape of a woman. As a result of the breast shape measurement of a living body A, it was measured that height of the breast was about 67.24mm and the bottom width was $13781.60mm^2$. This study is expected to contribute for collecting basic data of a female underwear industry and establishing a specification of a dimension system.

  • PDF

초정밀 엔코더를 위한 신호처리기법개발 (Signal Processing Algorithm for High Precision Encoder)

  • 정규원
    • 한국생산제조학회지
    • /
    • 제9권3호
    • /
    • pp.103-110
    • /
    • 2000
  • Shaft encoder which encodes the rotational angle of a shaft becomes more important recently due to factory automation and office automation. Although an absolute type encoder is more dsirable due to its convenience an incremental encoder is commonly used because of its cost and technical difficulties Fabricating a high resolution absolute encoder is very diff-cult because the physical size is limited by currently available technology. In order to overcome this difficulty Moire fringe can be used incorporated with gray code. In order to measure the position of fringes which move as the code disk rotates a neural network was developed in this paper. Formerly fringe position is usually measured by a sophisticated software which needs a little long calculation time. However using nerual network method can eliminate such calculation time even though it needs learning job The pro-posed method is verified through several experiments.

  • PDF

위상이동 그림자 무아레방법에서 형상측정 정확도의 개선 (Improvement of accuracy of surface measurement in the phase-shifting shadow moire method)

  • 유원재;강영준;권기용
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1995년도 추계학술대회 논문집
    • /
    • pp.402-406
    • /
    • 1995
  • The shadow moire is one the optical techniques which able to give contour lines of an object with respect to a master grating plane. The moire patterns are issued from the superposition of a grating and its shadow projected on the surface of an object. But in the conventional shadow moire method the reference grating and deformed grating are mutually dependent, it is impossible to obtain uniform phase shifts on the whole field by moving the reference grating. Here we propose ane trial to apply phase shifting to conventional shadow moire. When, in the conventional arrangement, Phase-shifting that is sctually constant regardless of fringe orders is achieved by moving the grating and the light source. Finally we obtained a better result by using this procedure and applied the phase shifting shadow moire to three dimensional measurement.

  • PDF

인체형상 측정을 위한 가상격자 영사식 무아레 방법에 관한 연구 (A Study on the Virtual Grating Projection Moire Topography for the Shape Measurement of Human Face)

  • 유원재;최정표;안중근;강영준
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2001년도 춘계학술대회 논문집
    • /
    • pp.49-52
    • /
    • 2001
  • Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topogrphy is very attractive because of it s high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the $2\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the $2\pi$-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

  • PDF

인체흉상 합성을 위한 3차원 형상 측정에 관한 연구 (A study on 3-D shape measurement for the composition of human bust)

  • 안중근;강영준;최정표;유원재
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 추계학술대회 논문집
    • /
    • pp.220-223
    • /
    • 1997
  • Moire topography method is a well-known non-contacting 3-D measuement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topography is very attractive because of it's high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the 2x-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the 2x-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

  • PDF

푸리에 변환을 이용한 미스얼라인된 Moire 무늬의 표준화 (Normalization of the Misaligned Moire Pattern Using Fourier Transform)

  • 박두원;삼본길춘
    • 비파괴검사학회지
    • /
    • 제15권2호
    • /
    • pp.386-394
    • /
    • 1995
  • 시편의 미소 변형을 측정하는 Moire법의 한 응용 방법인 미스얼라이먼트법을 이용하여 발생된 화상을 푸리에 변환에 의하여, 주파수 함수로 전환시킨 후 표준화 이론을 적용하여 시편의 변형을 Moire 무늬로 설명하고, 이를 뒷받침하는 식들을 유도하였다. 특히, 미스얼라인먼트법에서 발생되는 무늬의 회전 현상이나 무의 개수의 증가를 설명하고 이에 관련된 식들을 얻었다. 또한 무의 차수와 변형율과의 상관 관계를 보여주는 식을 주파수 벡터법과 기하하적인 방법으로 각각 유도하여, 이들 두식이 통상의 Moire법에서도 적용가능한 보다 유용한 식임을 확인하였다.

  • PDF