• Title/Summary/Keyword: ccd camera

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A CCD Camera Lens Degradation Caused by High Dose-Rate Gamma Irradiation (고 선량율 감마선 조사에 따른 렌즈의 열화)

  • Cho, Jai-Wan;Lee, Joon-Koo;Hur, Seop;Koo, In-Soo;Hong, Seok-Boong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.7
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    • pp.1450-1455
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    • 2009
  • Assumed that an IPTV camera system is to be used as an ad-hoc sensor for the surveillance and diagnostics of safety-critical equipments installed in the in-containment building of the nuclear power plant, an major problem is the presence of high dose-rate gamma irradiation fields inside the one. In order to uses an IPTV camera in such intense gamma radiation environment of the in-containment building, the radiation-weakened devices including a CCD imaging sensor, FPGA, ASIC and microprocessors are to be properly shielded from high dose-rate gamma radiation using the high-density material, lead or tungsten. But the passive elements such as mirror, lens and window, which are placed in the optical path of the CCD imaging sensor, are exposed to a high dose-rate gamma ray source directly. So, the gamma-ray irradiation characteristics of the passive elements, is needed to test. A CCD camera lens, made of glass material, have been gamma irradiated at the dose rate of 4.2 kGy/h during an hour up to a total dose of 4 kGy. The radiation induced color-center in the glass lens is observed. The degradation performance of the gamma irradiated lens is explained using an color component analysis.

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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Noncontact 3-dimensional measurement using He-Ne laser and CCD camera (He-Ne 레이저와 CCD 카메라를 이용한 비접촉 3차원 측정)

  • Kim, Bong-chae;Jeon, Byung-cheol;Kim, Jae-do
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.11
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    • pp.1862-1870
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    • 1997
  • A fast and precise technique to measure 3-dimensional coordinates of an object is proposed. It is essential to take the 3-dimensional measurements of the object in design and inspection. Using this developed system a surface model of a complex shape can be constructed. 3-dimensional world coordinates are projected onto a camera plane by the perspective transformation, which plays an important role in this measurement system. According to the shape of the object two measuring methods are proposed. One is rotation of an object and the other is translation of measuring unit. Measuring speed depending on image processing time is obtained as 200 points per second. Measurement resolution i sexperimented by two parameters among others; the angle between the laser beam plane and the camera, and the distance between the camera and the object. As a result of these experiments, it was found that measurement resolution ranges from 0.3mm to 1.0mm. This constructed surface model could be used in manufacturing tools such as rapid prototyping machine.

Accuracy Analysis of Aerial Triangulation Using Medium Format CCD Camera RCD105 (중형카메라의 항공삼각측량 정확도 분석)

  • Kang, Joon-Mook;Won, Jae-Ho;So, Jae-Kyeong
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.251-252
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    • 2010
  • Lately, airborne digital camera and airborne laser scanner in field of airborne surveying is used to build geography information such as DEM generation and terrain analysis. In this study, 3D position accuracy is compared medium format CCD camera RCD105 with high resolution airborne digital camera DMC. For this, test area was decided for aerial photograph and ground control points was selected in 1/1,000 scale digital map. In Result, Root Mean Square Error(RMSE) was analyzed between RCD105 and DMC after aerial triangulation.

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Development of Measuring System for Camera Lens Resolution Based on the MTF Performance (MTF 측정에 의한 카메라 렌즈 해상력 검사 시스템 개발)

  • 박희재;신호승;노영훈
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.629-634
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    • 2000
  • This System is developed for the estimation of the Camera Lens Resolution. Signal data proportional to light intensity is obtained and sampled from the 2D CCD. Based on the measured signal. the MTF charateristcs of a camera lens are measured. We could measure the sagittal and tangential MTF in the on and off-axis at the same time. The automatic measurig methods for optimal image plane, magnification, and best marginal direction of test lens are presented.

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Geometric Modelling and Coordinate Transformation of Satellite-Based Linear Pushbroom-Type CCD Camera Images (선형 CCD카메라 영상의 기하학적 모델 수립 및 좌표 변환)

  • 신동석;이영란
    • Korean Journal of Remote Sensing
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    • v.13 no.2
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    • pp.85-98
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    • 1997
  • A geometric model of pushbroom-type linear CCD camera images is proposed in this paper. At present, this type of cameras are used for obtaining almost all kinds of high-resolution optical images from satellites. The proposed geometric model includes not only a forward transformation which is much more efficient. An inverse transformation function cannot be derived analytically in a closed form because the focal point of an image varies with time. In this paper, therefore, an iterative algorithm in which a focal point os converged to a given pixel position is proposed. Although the proposed model can be applied to any pushbroom-type linear CCD camera images, the geometric model of the high-resolution multi-spectral camera on-board KITSAT-3 is used in this paper as an example. The flight model of KITSAT-3 is in development currently and it is due to be launched late 1998.

A study on the theoretical minimum resolution of the laser range finder (레이저 거리계의 이론적 최소 분해능에 관한 연구)

  • 차영엽;권대갑
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.644-647
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    • 1996
  • In this study the theoretical minimum resolution analysis of an active vision system using laser range finder is performed for surrounding recognition and 3D data acquisition in unknown environment. The laser range finder consists of a slitted laser beam generator, a scanning mechanism, CCD camera, and a signal processing unit. A laser beam from laser source is slitted by a set of cylindrical lenses and the slitted laser beam is emitted up and down and rotates by the scanning mechanism. The image of laser beam reflected on the surface of an object is engraved on the CCD array. In the result, the resolution of range data in laser range finder is depend on distance between lens center of CCD camera and light emitter, view and beam angles, and parameters of CCD camera.

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LARGE FORMAT CCD CAMERA FOR THE KISO 105 cm SCHMIDT TELESCOPE

  • YOSHIDA S.;AOKI T.;SOYANO T.;TARUSAWA K.;HASEGAWA T.
    • Journal of The Korean Astronomical Society
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    • v.29 no.spc1
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    • pp.381-383
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    • 1996
  • A new CCD camera equipped with a large format chip is now under construction for the Kiso 105-cm Schmidt telescope. We use SITe TK2048E, of which pixel size is 24 ${\mu}m$ and chip size is 48 mm square. TK2048E is thinned back-illuminated so that it has high sensitivity in U-band. The chip is cooled by a refrigerator instead of liquid nitrogen. MESSIA III is used as CCD control system.

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Measurement of Tool Wear using Machine Vision in Flat End-mill (머신비젼을 이용한 평 엔드밀 공구의 마모측정)

  • Kim, Tae-Young;Kim, Eung-Nam;Kim, Min-Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.53-59
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    • 2011
  • End milling is available for machining the various shape of products and has been widely applied in many manufacturing industries. The quality of products depends on a machine tool performance and machining conditions. Recognition characteristics of the cutting condition is becoming a critical requirement for improving the utilization and flexibility of present-day CNC machine tools. The measurement of tool wear would be performed by coordinate-measuring machine(CMM). However, the usage of CMM requires much time and cost. In order to overcome the difficulties, on-line measurement(OLM) system was applied for a tool wear measurement. This study shows a reliable technique for the reduction of machining error components by developing a system using a CCD camera and machine vision to be able to precisely measure the size of tool wear in flat end milling for CNC machining. The CCD camera and machine vision attached to a CNC machine can determine tool wear quickly and easily.

Visualization of Electro-hydrodynamic Ink Jetting using CCD Camera (CCD 카메라를 사용한 전기수력학적 잉크젯 토출 현상 가시화)

  • Kwon, Kye-Si;Lee, Dae-Yong
    • Journal of the Korean Society for Precision Engineering
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    • v.29 no.3
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    • pp.295-301
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    • 2012
  • The method for spraying of liquids through an electrical field has become a printing method since it can make very small droplet. For electro-hydrodynamic jet printing to become a reliable jetting tool, the jetting performance should be characterized with respect to various jetting conditions. To optimize jetting conditions, the jetting behavior should be measured. In this study, we present a visualization techniques to measure jetting behavior from electro-hydrodynamic (EHD) inkjet head. Unlike most previous method, we use the CCD camera to measure the jetting behavior. For this purpose, LED light is synchronized with jetting signal and sequential image was obtained by adjusting the delay time of the LED light. Finally, merits and demerits of using CCD camera were discussed to measure jetting image from EHD inkjet head.