• Title/Summary/Keyword: CCD(charge coupled device)

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Real time MTF Measurement of Copy Lenses by two-dimensional CCDs (2차원 CCD를 이용한 복사기 렌즈의 실시간 MTF 측정)

  • 조현모;이윤우;이인원;김태희;최옥식;이환규
    • Korean Journal of Optics and Photonics
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    • v.7 no.1
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    • pp.1-8
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    • 1996
  • Charge-coupled device(CCD) array detectors are widely used in real time modulation transfer function(MTF) measurement systems. This paper presents the characteristics of two-dimensional CCDs used in a real time MTF measurement system for copy lenses. The MTF characteristics of a copy lens measured by this equipment show different results according to the direction of shift register, shutter speed and the amplifier gain of CCDs. An object generator is fabricated to reduce the variation of MTF values for the irradiance nonuniformity in on-axis and off-axis image plane and this MTF equipment is calibrated by using a standard lens.

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Color Filter Array Interpolation Method Using Neural Networks (신경망을 이용한 Color Filter Array 보간 기법)

  • 고진욱;이철희
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.242-245
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    • 2000
  • In this paper, we present a color interpolation technique based on artificial neural networks for a single-chip CCD (charge-coupled device) camera with a Bayer color filter array (CFA). Single-chip digital cameras use a color filter array and an interpolation method in order to regenerate high quality color images from sparsely sampled images. We applied 3-layer feedforward neural networks in order to interpolate missing pixel from surrounding pixels. And we compared the proposed method with conventional interpolation methods such as the proposed interpolation algorithm based on neural networks provides a better performance than the conventional interpolation algorithms.

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Data extraction from distorted image in holographic data storage (홀로그래픽 데이터 저장 장치에서 왜곡된 이미지로부터의 데이터 추출)

  • 전승준;양병춘;이병호
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.02a
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    • pp.60-61
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    • 2000
  • 홀로그래픽 데이터 저장 장치(holographic data storage)는 1960년대에 이미 아이디어가 출현하였고, 1990년대에 들어서 SLM(spatial light modulator)과 CCD(charge coupled device) 등 관련 기술의 발달과 함께 향후 늘어날 대용량 저장 장치 시장에 대한 전망 등에 힘입어 주목받기 시작하였다. 홀로그래픽 데이터 저장 장치의 중요한 장점은 대용량의 정보를 고속으로 처리할 수 있고, 특히 페이지 단위로는 병렬 접근이 가능하다는 것인데, 이를 위해서 반드시 해결되어야 할 것이 픽셀 매치(pixel-match)이다. (중략)

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Real Time Spectroelectrochemical Experiments with a Multichannel Detector

  • Sun-Il Mho;Sally N. Holer;Bum-Soo Kim;Su-Moon Park
    • Bulletin of the Korean Chemical Society
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    • v.15 no.9
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    • pp.739-743
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    • 1994
  • A spectroelectrochemical system assembled with a white light source, bifurcated optical fiber, Oriel Multispec spectrograph, and a charge-coupled device (CCD) detector is described. The system is shown to be capable of acquiring a whole spectrum in the spectral range of 290-800 nm in 25 ms or a longer period during electrochemical experiments at reflective working electrodes such as platinum or mercury. The utility of the system in studying electrochemical reactions during the potential scan, galvanostatic electrolysis, or after the potential step is demonstrated.

Development of Vision system for Back Light Unit of Defect (백라이트 유닛의 결함 검사를 위한 비전 시스템 개발)

  • Han, Chang-Ho;Oh, Choon-Suk;Ryu, Young-Kee;Cho, Sang-Hee
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.4
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    • pp.161-164
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    • 2006
  • In this thesis we designed the vision system to inspect the defect of a back light unit of plat panel display device. The vision system is divided into hardware and inspection algorithm of defect. Hardware components consist of illumination part, robot-arm controller part and image-acquisition part. Illumination part is made of acrylic panel for light diffusion and five 36W FPL's(Fluorescent Parallel Lamp) and electronic ballast with low frequency harmonics. The CCD(Charge-Coupled Device) camera of image-acquisition part is able to acquire the bright image by the light coming from lamp. The image-acquisition part is composed of CCD camera and frame grabber. The robot-arm controller part has a role to let the CCD camera move to the desired position. To take inspections of surface images of a flat panel display it can be controlled and located every nook and comer. Images obtained by robot-arm and image-acquisition board are saved on the hard-disk through windows programming and are tested whether there are defects by using the image processing algorithms.

4S-Van: A Prototype Mobile Mapping System for GIS

  • Lee, Seung-Yong;Kim, Seong-Baek;Choi, Ji-Hoon;Lee, Jong-Hun
    • Korean Journal of Remote Sensing
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    • v.19 no.1
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    • pp.91-97
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    • 2003
  • The design of Graphic Information System(GIS) in various applications is suffering from the difficulty of data acquisition, which is labor-intensive and time consuming. In order to provide the spatial data rapidly and accurately, 4S-Van, a prototype mobile mapping system, has been developed. The 4S-Van consists of 1)Global Positioning System(GPS), Inertial Navigation System(INS) for estimating the geographic position and attitude of the moving van, i.e.,(x, y, z) and the direction of the Van, 2) Charge Coupled Device(CCD) camera and laser scanner for capturing images and for measuring depth from geographic objects, and 3) External Synchronization Device(ESD) and industrial PC for synchronizing data from GPS/INS/CCD camera and for storing the data. In this paper, we present the design and implementation of the proto-Dpe 4S-Van system for spatial data acquisition for various GIS applications.

Real-Time Automatic Target Detection in CCD image (CCD 영상에서의 실시간 자동 표적 탐지 알고리즘)

  • 유정재;선선구;박현욱
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.6
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    • pp.99-108
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    • 2004
  • In this paper, a new fast detection and clutter rejection method is proposed for CCD-image-based Automatic Target Detection System. For defence application, fast computation is a critical point, thus we concentrated on the ability to detect various targets with simple computation. In training stage, 1D template set is generated by regional vertical projection and K-means clustering, and binary tree structure is adopted to reduce the number of template matching in test stage. We also use adaptive skip-width by Correlation-based Adaptive Predictive Search(CAPS) to further improve the detecting speed. In clutter rejection stage, we obtain Fourier Descriptor coefficients from boundary information, which are useful to rejected clutters.

Correction for Scanning Errors of a CCD Camera Scanner (CCD Camera Scanner의 스캐닝 왜곡 보정기법 연구)

  • 안기원
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.12 no.2
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    • pp.173-180
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    • 1994
  • One can see more and more photograrmmetric applications dealing with the extraction of information from images obtained with CCD (Charge Coupled Device) camera scanners. In order for this information to be useful, the scanning errors of scanners must be known through a calibration. Investigation of this study is given to the detailed procedure of the correction for scanning errors created during the scanning of photographs with CCD camera scanner using the three kinds of high resolution reseal plates prepared. The geometric corrected digital images for scanning errors were generated and the accuracy of the resulting new images for each types of plates were checked comparing its image coordinates with there corresponding ground coordinates for the check points.

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Appropriate Digital Camera System for Digital Ultraviolet Photography (디지털 자외선 사진을 위한 적정 디지털 카메라 시스템)

  • Lee, Young-Kyu;Har, Dong-Hwan
    • The Journal of the Korea Contents Association
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    • v.10 no.7
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    • pp.40-48
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    • 2010
  • Reflected-Ultraviolet photography is applied to the evidence of crime, Archaeology, and Dermatology. In the past, Ultraviolet photography was done with standard black-and-white film. Because emulsion of film is more sensitive to near UV light than CCD(Charge Coupled Device) or CMOS(Complementary Metal-Oxide-Semiconductor)of digital camera. In this research, we purpose to improve qulity of ultraviolet photographs and to find out the best alternative digital camera by utilizing a cunsumer digital camera. To achieve theses, we removed IR cutoff filter from digital camera. And by using modified UV pass filter, we verified the increase of image resolution of digital ultraviolet photographs. Also, we analyze reproducibility of digital ultraviolet photographs according to type, size, pixel of image sensor. Furthermore, this research resulted in the development of an practical digital camera system by utilizing a cunsumer digital camera. Eventually, it will contribute to practical use in the various field of digital ultraviolet photographs