4.55-in. HDTV poly-Si TFT light valve for LCD projectors

Abstract

A 4.55-in. HDTV (high-definition television) poly-Si TFT (thin-film transistor) light valve with 960*1439 pixels for LCD (liquid crystal display) projectors has been developed. This is the smallest transmission-type HDTV TFT light valve yet produced, and it has an aperture ratio which is higher than 30% despite the use of a redundant TFT structure and sufficient storage capacity in the pixels. Optimization of redundant poly-Si TFT circuits with sufficient storage capacitance has realized excellent image quality suitable for HDTV. Laser cutting and deposition technology make it possible to repair most of the defects in the TFT substrate before LCD assembly. The repaired points are reliable and have no effect on the image quality because they are covered with passivation and alignment layers after repairing.<>