• Title/Summary/Keyword: photo sensor

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Real time control special quality research for $CO_2$ laser's output change rate stability for accumulation style surgical operation rehabilitation of ventriculus that use Photosensor (Photosensor를 이용한 재활 치료형을 위한 $CO_2$ laser 의 출력변동율 안정을 위한 실시간 제어특성 연구)

  • Kim, Whi-Young
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.1015-1016
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    • 2006
  • The important parameters deciding the fluctuation of Accumulation style surgical operation of ventriculus laser beam are smoothing capacitor, frequency and he characteristics of laser resonator. In this thesis, we control the fluctuation of medical $CO_2C$ laser in realtime by changing Duty-Ratio of IGBT and switching frequency with fixed the smoothing capacitor to improve the fluctuation of laser beam. We detect the light on laser resonator using a CdS photo sensor to improve ripple factor of laser beam and feedback fluctuated signals refined by a band pass filter into the control circuit to stabilize fluctuation actively. There is much to be desired in the realtime controlling technique of the light on Accumulation style surgical operation of ventriculus laser discharge tube in electrical signal. We propose switching control technique with microprocessor and photo sensing technique by controlling switch devices optimum operation and feedback signals detected by a photo sensor into the laser power supply in order to improve ripple factor of the $CO_2$ laser beam.

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The Effect of Light on Amorphous Silicon Thin Film Transistors based on Photo-Sensor Applications

  • Ha, Tae-Jun;Park, Hyun-Sang;Kim, Sun-Jae;Lee, Soo-Yeon;Han, Min-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.953-956
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    • 2009
  • We have investigated the effect of light on amorphous silicon thin film transistors based photo-sensor applications. We have analyzed the instability caused by electrical gate bias stresses under the light illumination and the effect of photo-induced quasi-annealing on the instability. Threshold voltage ($V_{TH}$) under the negative gate bias stress with light illumination was more decreased than that under the negative gate bias stress without light illumination even though $V_{TH}$ caused by the light-induced stress without negative gate bias was shifted positively. These results are because the increase of carrier density in a channel region caused by the light illumination has the enhanced effect on the instability caused by negative gate bias stress. The prolonged light illumination led to the recovery of shifted VTH caused by negative gate bias stress under the light illumination due to the recombination of trapped hole charges.

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2.2 “ QVGA LTPS LCD Panel integrated with Ambient light Sensor

  • Weng, Chien-Sen;Chao, Chih-Wei;Tseng, Hung Wei;Peng, Chia-Tien;Lin, Kun-Chih;Gan, Feng-Yuan
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1319-1322
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    • 2007
  • Planar PIN photodiode is compatible with LTPS process, and its fabrication requires no additional manufacturing process. In this study we design the optimum dimension of PIN diodes with two nitride layers to improve the efficiency of PIN diodes. The PIN photo sensor shows very good sensitivity to ambient light illuminance.

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Obstacle Avoidance and Lane Recognition for the Directional Control of Unmanned Vehicle

  • Kim, Chang-Man;Moon, Hee-Chang;Kim, Sang-Gyum;Kim, Jung-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.34.6-34
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    • 2002
  • 1. Introduction 2. System Configuration 2.1 Control System 2.1.1 Longitudinal control 2.1.2 Lateral control 2.2 Sensor System 2.2.1 Photo interrupt 2.2.2 Ultrasonic sensor 2.3 Vision system 2.4 Communication system 2.4.1 Data communication 2.4.2 Image Communication 3. Test and Result 3.1 Vision test 3.2 Ultrasonic sensor test 4. Conculsion. Acknowledgment References.

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Dual Mode AMOLED Pixel Circuit

  • Bae, Byung-Seong;Son, Yong-Duck;Jang, Jin;Lee, Ki-Yong;Chung, Ho-Kyoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1082-1085
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    • 2006
  • We proposed dual mode pixel circuit in AMOLED (active matrix organic light emitting device). After light emitting period of OLED, we used it as a photo sensor. We measured photo current of OLED and simulated the proposed pixel circuit to verify it's function of dual mode, that is lighting and sensing.

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Optical issues of OLED displays with a photo sensor for in-pixel optical feedback

  • Oepts, Wouter;Giraldo, Andrea;Lifka, Herbert;Fish, David;Young, Nigel
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.968-971
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    • 2005
  • Amorphous silicon photo diodes incorporated in a polyLED stack are applied in in pixel opticalfeedback to compensate for polyLED degradation. Large quantum efficiencies and perfect linearity are demonstrated. The photosensitivity is in agreement with optical modeling of the stack. A new scheme for ambient and cross talk light cancellation is given.

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Estimation of $CO_2$ Laser Weld Bead by Using Multiple Regression (다중회귀분석을 이용한 $CO_2$레이저 용접 비드 예측)

  • 박현성;이세헌;엄기원
    • Journal of Welding and Joining
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    • v.17 no.3
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    • pp.26-35
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    • 1999
  • On the laser weld production line, a slight alteration of the welding condition changes the bead size and the strength of the weldment. The measurement system is produced by using three photo-diodes for detection of the plasma and spatter signal in $CO_2$ laser welding. The relationship between the sensor signals of plasma or spatter and the bead shape, and the mechanism of the plasma and spatter were analyzed for the bead size estimation. The penetration depth and the bead width were estimated using the multiple regression analysis.

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Development of the speed-measurement device of motor in a crane (기중기의 모터속도 측정장치 개발)

  • 김강철
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2000.10a
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    • pp.638-641
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    • 2000
  • The conventional motor in a crane has a tan generator to feed back the number of turns. The tan generator is contacted to a motor shaft through the coupling. Don has been often generated because the coupling has worn out while the motor is turning. In this paper, we design the speed-measurement device of motor in a un. The device is composed of PIC16F84 controller, photo-sensor, and analog-to digital converter. The photo sensor measures the turn of a motor without contact so the device decreases the probability of errors. And The device can acknowledge the turn direction of the motor with a gin81e senor and two color reflectors.

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Fine Gap Control Using Pneumatic Servo System (공압서보시스템에 의한 미세 간극제어 시스템 설계)

  • 김동환;김영진;정대화
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.12
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    • pp.45-56
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    • 2002
  • A pneumatic servo system requiring a fine gap control in a photo-electric sensor which is used for a LCD array detection device is introduced. The gap controlled by the pneumatic servo system remains within around 50~80 ${\mu}{\textrm}{m}$, and the system possesses an effect to eliminate undesirable particles on the LCD plate by blowing air out. The air flow rate is initially controlled by a servo valve and expanded by a booster valve, thus the controlled air pressure contributes to maintaining an appropriate gap between the LCD plate and photo-electric sensor An air floating plate of two degrees of freedom is designed and fabricated, and a fine tilting motion control is also implemented by assigning different gap commands. The pressure control and direct gap control are proposed, and each performance is verified experimentally.

Development of a computer mouse by tracking head movements and eyeblink (머리 움직임과 눈 깜박임을 이용한 컴퓨터 마우스 개발)

  • Park, Min-Je;Kang, Shin-Wook;Kim, Soo-Chan
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.1107-1108
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    • 2008
  • The purpose of this study is to develope a computer mouse using the head movements and eye blink in order to help the disability persons who can't move the hands or foot because of car accident or cerebral apoplexy. The mouse is composed of two gyro-sensors and photo sensor. The gryo-sensors detect the head horizontal and vertical angular velocities, respectively. The photo sensor detect the eye blink to perform click, double click, and to reset the head position. In the results, we could control the mouse points in real time using the proposed system.

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