基于photo-TFT的像素设计解析.pptVIP

基于photo-TFT的像素设计 导 师：张盛东 汇报人：何常德 2014-05-14 组会交流报告 Outline Patent（US6947102，Light Sensitive Display which senses decreases in light） Photo sensor pixel with two TFTs Background of the invention optically-based touch screen Common techniques employed in touch screens for detecting the location of a touch include mechanical buttons, crossed beams of infrared light, acoustic surface Waves, capacitance sensing, and resistive membranes. Plannar System Inc. (US) Technology Touch Points Touch Input Size Accuracy Picture Quality Applications Resistive 1 Any Input 15-19 Okay Fair, Coating, Oversscreen Great value for basic touch SAW 1 Finger and soft stylus only 15-19 Okay Good,Glass Great value for basic touch; especially when a clean screen is important Optical/IR Up to 32 Any input 42+/VideoWall Varies Good, Glass Supports test gestures, but implementation is critical Projected Capacitive 2 -10 Finger only 15-32 Excellent Good, Glass Best overall experience and look. Similar to smartphones Plannar System Inc. (US) Background of the invention Touch screens that have a transparent surface Which mounts between the user and the displays viewing surface have several drawbacks. For example, the transparent surface, and other layers between the liquid crystal material and the transparent surface may result in multiple reflections which decreases the displays contrast and produces glare. Moreover, adding an additional touch panel to the display increases the manufacturing expense of the display and increases the complexity of the display. Also, the incorporation of the touch screen reduces the overall manufacturing yield of the display. Detailed description With the realization that amorphous silicon transistors are sensitive to light incident thereon, the present inventors determined that such transistors within the active matrix layer may be used as a basis upon which to detect the existence of or non-existence of ambient light incident thereon (e.g., relative values the