LCD Embedded Hybrid Touch Screen Panel Based on a-Si:H TFT

  • You, Bong-Hyun (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD) ;
  • Lee, Byoung-Jun (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD) ;
  • Lee, Jae-Hoon (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD) ;
  • Koh, Jai-Hyun (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD) ;
  • Takahashi, Seiki (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD) ;
  • Shin, Sung-Tae (LCD R&D Center, LCD Business, DS Division, SAMSUNG ELECTRONICS CO., LTD)
  • Published : 2009.10.12

Abstract

A new hybrid-type touch screen panel (TSP) has been developed based on a-Si:H TFT which can detect the change of both $C_{LC}$ and photo-current. This TSP can detect the difference of $C_{LC}$ between touch and no-touch states in unfavorable conditions such as dark ambient light and shadows. The hybrid TSP sensor consists of a detection area which includes one TFT for photo sensing and two TFTs for amplification. Compared to a single internal capacitive TSP or an optical sensing TSP, this new proposed hybrid-type TSP enables larger sensing margin due to embedding of both optical and capacitive sensors.

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