Birth of the Innovative Overdrive Technology for Liquid Crystal: Paving the Way for Practical Use of LCD Televisions

Abstract

This article describes our experience developing innovative display technologies with the aim of providing hints for researchers to break away from conventional wisdom. In the 1990s, we focused mainly on liquid crystal display (LCD) technologies for creating and developing the new flat-panel TV market, despite claims that the motion blur problem for LCD TVs could not be solved without materials featuring ultrafast response times. We then discovered that motion blur is not due to a binary response, as was commonly believed at the time, but rather a drastically degraded gray-level response and decreased driving voltage due to electrostatic capacity change according to dynamic rotation of liquid crystal molecules. On the basis of a novel image-lag mechanism, we invented the overdrive method to emphasize the voltage applied to the liquid crystal for only a certain period according to change in picture brightness for high-speed response LCD TVs. This overdrive technology is now a de facto standard technology for LCD TVs, though the time-to-market exceeded 13 years. This article describes why so much time was required and how many issues were resolved to realize this revolutionary innovation.