We have developed active matrix capacitive sensors for detecting touch events in low‐temperature polycrystalline silicon (LTPS) TFT LCDs with Fringe‐Field Switching (FFS) technology. These sensors enable touch events to be detected regardless of ambient light and enable touch events to be input simultaneously at 3 or more points.

We have developed a 1300-dpi optical image sensor using a hydrogenated amorphous silicon (a-Si:H) pin diode array driven by low-temperature polycrystalline silicon (LTPS) thin film transistors (TFT) on a glass substrate. This paper describes a new architecture for achieving a high-resolution optical image sensor using LTPS TFT production equipment.

Abstract— An active‐matrix capacitive sensor for use in AMLCDs as an in‐cell touch screen has been developed. Pixel sensor circuits are embedded in each pixel by using low‐temperature polycrystalline‐silicon (LTPS) TFT technology. It detects a change in the liquid‐crystal capacitance when it is touched. It is thin, light weight, highly sensitive, and detects three or more touch events simultaneously.