用于头显液晶像源LED背光的双自由曲面透镜阵列设计

发布时间：2018-08-13 20:08

【摘要】：发光二极管(LED)已经成为头盔显示器液晶像源主流背光源。LED发散角较大,大量的光线无法得到有效利用而造成能量的浪费,故需要对LED进行二次光学设计以有效提高光效。背光包括由若干个LED组成的阵列。对单个LED设计了双曲面透镜,形成了8 mm直径的均匀圆形光斑。对单个透镜进行切割,以形成矩形光斑。但由于切割面的全反射,矩形面积内存在亮斑。对透镜进行了优化设计,获得了亮度均匀的矩形光斑。4个矩形透镜拼接成透镜阵列。为消除杂散光斑,对透镜再次进行了优化设计。根据设计结果加工了透镜阵列并对背光进行了实际测试。测试结果表明:和传统背光结构相比,采用两层扩散膜和透镜阵列后,背光亮度提高了96.4%,非均匀性由23.8%略提高到23.1%,半亮度视角由39°降低到23°。满足头盔显示器液晶像源背光的要求。
[Abstract]:Light emitting diode (LED) has become the mainstream backlight of head-mounted display liquid crystal image source. The divergence angle of LED is large, and a large amount of light can not be used effectively, which results in waste of energy. Therefore, the secondary optical design of LED is needed to improve the light efficiency effectively. Backlight consists of an array of several LED. A hyperboloid lens is designed for a single LED to form a uniform circular spot with a diameter of 8 mm. A single lens is cut to form a rectangular spot. However, due to the total reflection of the cutting surface, there are bright spots in the rectangular area. The optimum design of the lens is carried out, and the rectangular spot with uniform brightness is obtained, and four rectangular lenses are spliced into a lens array. In order to eliminate the stray spot, the lens was optimized again. The lens array was fabricated according to the design results and the backlight was tested. The results show that, compared with the traditional backlight structure, the backlight brightness is increased by 96.4x, the inhomogeneity is slightly increased from 23.8% to 23.1C, and the half-view angle is reduced from 39 掳to 23 掳by using two-layer diffusion film and lens array. To meet the helmet display LCD image source backlight requirements.
【作者单位】：合肥工业大学特种显示技术教育部重点实验室特种显示技术国家工程实验室现代显示技术省部共建国家重点实验室光电技术研究院;
【基金】：安徽省自然科学基金(1408085MKL86)
【分类号】：TN873.93

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