Tandem Light-Guides With Micro-Line-Prism Arrays for Field-Sequential-Color Scanning Backlight Module

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%.