Hiroyuki Nagata

Orientations and viewing angle dependence of twisted ferroelectric liquid crystal

Abstract Orientations of liquid crystal for TFLC could be controlled by selecting sign of Ps, polarity of alignment layers and rubbing directions. Characteristic viewing angle dependencies of transmittance based on the declined orientation of liquid crystal could be observed for the cell with uniform orientation.

A transport stream processor for HDD recording and playback of HDTV signal

This paper describes the architecture of the transport stream processor system for the digital HDTV receiver with HDD recording capability. The transport stream processor consists of a RISC processor, a content protection circuit, an IDE controller, and a bus interface. The transport stream processor generates the low clock rate partial transport streams by utilizing the bit rate control algorithm with the recording information table and the modulo algorithm. This system realizes a high-speed signal processing of multiple HDTV transport streams for HDD recording and playback for the storage digital broadcasting.

A 15‐in. XGA thresholdless antiferroelectric LCD addressed by TFTs and using the quasi‐dc driving method

— A 15-in. TFT-LCD with XGA resolution using thresholdless antiferroelectric liquid crystal (TLAF) has been developed. TLAF materials show V-shaped switching and enable display of analog gray scale, wide viewing angle, and fast response. However, in the case that high-resolution TFT-LCDs using materials with large spontaneous polarization such as TLAF were driven by the conventional method, alternating current (ac) driving, the obtained contrast ratio was limited because of a sharp decline of holding voltage due to the growth of a depolarization field. In order to enhance the contrast ratio, a novel driving method referred to as quasi-dc driving was proposed. In the quasi-dc driving, the polarity of the applied voltage to liquid crystals inverts at certain intervals of several seconds. Moreover, the applied voltage and the charging time at the time of polarity inversion are increased more than the intended signals. By this method, the 15-in. TFT-LCD using TLAF with high contrast ratio (more than 100:1) and wide viewing angle was realized.

A transport stream processing LSI for HDD recording and playback of HDTV

This paper describes a transport stream control LSI for digital HDTV receivers with HDD recording capability. A high performance HDD playback function using the partial transport stream is realized by a special designed RISC processor and the bitrate control algorithm in this new LSI.