Tandem light-guides with micro-line-prism arrays for field-sequential-color scanning backlight module

Abstract—An optically partitioned backlight system consisting of tandem wedge-shaped light-guides (LGs) with micro-line-prism arrays was developed for scanning field-sequential-color (FSC) liquid crystal display (LCD) in large size. The unit of wedge-shaped LG combined with a light-emitting diode (LED) light-bar was designed and fabricated to collimate the extraction light within a narrow angular extent. Based on the edge lighting approach, the volume of backlight system can be reduced down to 25 mm without sacrifice of the optical behavior. As a result, 2750 nits average luminance subject to 50 % duty cycle and 83 % uniformity can be achieved. The leakages into the consecutive adjacent blocks were well suppressed to 11.86%. Index Terms—Field-sequential-color (FSC) liquid crystal dis-play (LCD), micro-line-prism arrays, scanning backlight, tandem light-guides (LGs). I