Light Guide Technology
A light guide ( light conductive plates ) is an optical element which efficiently guides incident rays from one end to another end, by employing inner reflection of transparent resin such as acrylic resin. Conventionally, a light guide has been used for dashboard displays. Recently, however, it has drawn attention as a backlight for LCD monitors. The cross-section and surface shape should be formed in order for light to be emitted evenly by taking out incident rays from the light source little by little. Thus, a uniform luminescent surface can be achieved, which is necessary for backlighting.

Applied Products of Light Guides
Originally, a light guide was used for displays. Thanks to functions of the light guide, elongated displays such as car speedometers or radio tuning meters can be illuminated with only one light. The existence of the light guide was brought to attention as a backlight since LCD monitors have become popular. This means that the primary factor for the commercialization of the LCD monitor was how uniform surface light emission can be achieved in developing efficient backlighting.