Touch‐screen panel integrated into 12.1‐in. a‐Si:H TFT‐LCD

Abstract

A touch‐screen‐panel (TSP) embedded 12.1‐in. LCD employing a standard existing a‐Si:H TFT‐LCD process has been successfully developed. Compared with conventional external touch‐screen panels, which use additional components to detect touch events, the new internal TSP exhibits a clearer image and improved touch feeling, as well as increased sensing speed using discrete sensing lines to enable higher‐speed sensing functions including handwriting. The new internal digital switching TSP can be fabricated with low cost because it does not require any additional process steps compared to a standard a‐Si:H TFT‐LCD.

38.1: Embedded Liquid Crystal Capacitive Touch Screen Technology for Large Size LCD Applications

“…6 (2-GP). Two sensor pixels, S(1) and S(3), are driven by G1 and G3 gate signals simultaneously, therefore, the readout current is increased to I ro (1) +I ro (3). Here, the sensors are also reset by G2 and G4 gate signals simultaneously.…”

“…Recently new types of embedded TSP technology have been reported. One is a digital switching method in a 12.1-inch a-Si:H TFT LCD [3]. In that method, internal electrodes in the upper and lower glass are shorted by touch events, and the touch signal is sent to a readout IC.…”