用于激光背光源电视的扫描分光与消散斑系统

针对单颗激光二极管光功率过高不能直接用于激光液晶电视光源阵列的限制,本文设计了将高功率激光束分为多束功率接近的子光束的扫描分光系统,从而为液晶电视提供激光背光。系统中激光器发出的准直光束经过扫描振镜进行二维扫描后,经凸透镜和柱面透镜会聚成一条细线型光束耦合进一维多模光纤阵列,从而达到分光的目的。此外,基于扫描振镜和多模光纤实现了系统散斑的抑制。实验结果显示,11根光纤的平均单根出射功率为674.13μW,离散系数为16%,平均散斑对比度为0.162。使用激光作为背光源的激光液晶电视因其优秀的显示性能而具备强大的市场竞争力和广阔的市场前景。

Scanning beam splitting and speckle reduction system for laser backlight TV

Lasers demonstrate characteristics of high brightness and good monochromaticity. Moreover, the cost of liquid crystal display (LCD) planes are low as they have been developed extensively. Because of their excellent display performance, laser LCD televisions (TVs), which use lasers as their backlight, demonstrate strong market competitiveness and extensive market potential. The use of a light source array is a common technique for backlight system design. To limit the high power supplied by a single laser diode to an array, this study designed a scanning beam splitting system that divided the high-power laser beam into multiple sub-beams with sufficient power to provide a laser backlight for LCD TVs. The collimated laser beam in this system was initially scanned in two dimensions by a galvanometer scanner and then made to converge into a narrow linear beam by a convex lens and a cylinder lens; finally, it was coupled into an optical multimode fiber array. Thus, beam splitting was achieved. In addition, based on the scanning mirror and multimode fibers, the system also exhibited a speckle reduction effect. The experimental results demonstrated that the coefficient of variation in the average output power of 11 fibers is 16%, with an average value of 674.13 μW, and their average speckle contrast is 0.162.