基于多角度散斑曝光实现大散射角全息扩散片的制备  

Fabrication of Holographic Diffuser with Large Scattering Angle Realized by Multi-Angle Speckle Exposure

作　　者：杨朝雄 江海波[1] 孙秀辉[1] 刘毅 杨正[1] 房启鹏 尹韶云[1,2] Yang Chaoxiong;Jiang Haibo;Sun Xiuhui;Liu Yi;Yang Zheng;Fang Qipeng;Yin Shaoyun(Chongging Institute of Green and Itellient Technology,Chinese Academy of Sciences,Chongqing 400714,China;University of Chinese Academy of Sciences,Beijing 100049,China;Chongging BOE Optoelectronics Technology Co,LTD.Chongqing 400714,China)

机构地区：[1]中国科学院重庆绿色智能技术研究院,重庆400714 [2]中国科学院大学,北京100049 [3]重庆京东方光电科技有限公司,重庆400714

出　　处：《光学学报》2021年第16期41-46,共6页Acta Optica Sinica

基　　金：国家重点研发计划(2017YFB1002902);国家自然科学基金(61475199);重庆市科技局(cstc019jscx-mbdxX0019)。

摘　　要：光学扩散片是液晶显示器中的关键元件,兼具广角、高透过率、高均匀性的扩散片一直是液晶显示领域的重要研究目标。基于Helmholtz-Kirchhoff理论,推导了激光透过粗糙表面的散斑强度频谱分布,提出通过特定入射角度的多个光束依次照射粗糙表面形成散射场叠加曝光的全息扩散片设计方法。该方法拓宽了全息扩散片的散射角度,提升了散射强度的均匀性。搭建了全息扩散片的制作光路,采用上述方法制作了全息扩散片,测量获得的远场强度分布与仿真结果能很好地吻合,散射角的半峰全宽达到130°,透过率达到90%以上,扩散系数达到92%,同时实现了广角、高透过率和高亮度均匀性,在液晶显示中具有潜在的应用前景。Optical diffusers are key components in liquid crystal displays(LCDs). Diffusers with wide angles, high transmittance, and great uniformity have always been an important research goal in the LCD field. Based on the Helmholtz-Kirchhoff theory, the spectral distribution of speckle intensity for laser passing through a rough surface is derived. A design method for holographic diffusers is proposed, which is based on the superposition exposure of scattering fields formed by multiple beams at specific incident angles irradiating a rough surface in turn. This method broadens the scattering angle of holographic diffusers and improves the uniformity of scattering intensity. The fabrication path to holographic diffusers is made and holographic diffusers are fabricated by the proposed method. The far-field intensity distribution measured by this method is in good agreement with the simulation results. The full width at half maximum(FWHM) of scattering angles reaches 130°;the light transmittance is more than 90%, and the diffusion coefficient is as high as 92%. In addition, wide angles, high transmittance, and great brightness uniformity are realized. This method has potential application prospects in LCDs.

关 键 词：全息 散斑 大角度 散射 

分 类 号：O436[机械工程—光学工程]