Liquid Crystal Light Shutters for Simultaneous Control of Haze and Transmittance

Recently, see-through displays have been attracted much attention as next-generation displays. There are two basic technologies by which we can realize a see-through display: organic light-emitting diodes (OLEDs) and liquid crystal (LC) displays. The pixel structure of a see-through display includes a transparent window area through which the background image can be seen. Therefore, background images are always seen along with the displayed image. In addition, a see-through display using OLEDs cannot provide the black color. As a result, a see-thorough display exhibits poor visibility. This inevitable problem can be solved by placing a light shutter at the back of a see-through display. Light shutter technology can be divided into two types; light absorption and light scattering. Light shutter based on light absorption can be used to control the transmittance, but it cannot block the object behind the display panel completely. Light shutters based on light scattering can be used to control the haze, but it cannot provide black color. To realize a high-visibility see-through display, we need a light shutter by which we can control haze and transmittance simultaneously. In this talk we would like to introduce technologies for LC light shutters by which we can block the background image and provide black color by utilizing light scattering and absorption effects simultaneously.