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Journal of Display Technology

Journal of Display Technology


  • Vol. 7, Iss. 12 — Dec. 1, 2011
  • pp: 679–683

Gap-Type a-Si TFTs for Front Light Sensing Application

Ya-Hsiang Tai, Lu-Sheng Chou, and Hao-Lin Chiu

Journal of Display Technology, Vol. 7, Issue 12, pp. 679-683 (2011)

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The photo effect of gap-gate type hydrogenated amorphous silicon thin-film transistor (a-Si:H TFT) has been studied to be employed as light sensors owing to its outstanding photosensitivity. It can be operated in on region to provide a higher current level as the sensing signal. However, the gap–gate a-Si:H TFT suffers from some problems such as the photo-current degradation resulted from illuminations and the disturbance of the backlight source when it is used as the sensor in display panel. A new method is proposed to overcome the above issues, which gives a feasible way for this kind of TFT to be used in TFT LCD panel. In this paper, the operation of the sensing method is fully described.

© 2011 IEEE

Ya-Hsiang Tai, Lu-Sheng Chou, and Hao-Lin Chiu, "Gap-Type a-Si TFTs for Front Light Sensing Application," J. Display Technol. 7, 679-683 (2011)

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