热压印成型复合微透镜阵列的微光学照明特性  

Micro-optical illumination properties of hierarchical microlens arrays formed by hot-embossing

作　　者：胡满凤 李磊 谢晋[2] HU Manfeng;LI Lei;XIE Jin(School of Electrical Engineering,Guangzhou Railway Polytechnic,Guangzhou 511300,China;School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]广州铁路职业技术学院电气工程学院,广东广州511300 [2]华南理工大学机械与汽车工程学院,广东广州510641

出　　处：《光学精密工程》2024年第9期1371-1383,共13页Optics and Precision Engineering

基　　金：广东省基础与应用基础研究基金资助项目(No.2020A1515111200);广州铁路职业技术学院新引进人才科研启动项目(No.GTXYR2319);国家自然科学基金资助项目(No.52375493)。

摘　　要：在LED照明中,光线分布不均产生的眩光及光线中的紫外光、蓝光成分容易造成视觉疲劳和眼睛损伤,目前主要是以调节光源为主,纳米级光波段调节的表面结构加工成本较高。因此,利用热压印快速成型技术开发了一种微米尺度的复合微透镜阵列导光板,探究健康照明的复合微透镜尺度效应。首先分析微棱镜表面小微透镜的深宽比与反射电场分布的关系,然后研究导光板的微结构参数对漫反射率、镜面反射率和透射率的影响。最后,对比市面上丝网印刷微点、微棱镜阵列等结构导光板,研究复合微透镜微米尺度对照度、均匀度等微光学性能的影响。分析表明:当小微透镜深宽比在0.6~1内时,紫外光和蓝光的反射面有更小的反射电场变异系数,说明其漫反射大。实验结果表明:热压印技术可以在4 s内将微透镜高5~30μm和微棱镜高10~80μm的复合微透镜阵列导光板加工成型;照度均匀度随着小微透镜深宽比的增大而增大,照度分别比微棱镜和丝网印刷微点阵列提高45%和83%;与微棱镜相比,紫外光和蓝光的漫反射率分别提高8%和18%,镜面反射率下降80%~83%。控制复合微透镜的深宽比可以减少照明眩光,抑制紫外光和蓝光。In LED lighting,glare from uneven light distribution,along with ultraviolet and blue light,can lead to visual fatigue and eye damage.Currently,adjustments are primarily made to the light source,and modifying the surface structure at the nanoscale is costly.To address this,a microscope-scale hierarchical microlens array light guide plate(LGP)has been developed using hot-embossing rapid prototyping technol⁃ogy to examine the impact of the scale of hierarchical microlenses on health lighting.The study first analyz⁃es the relationship between the microlens aspect ratio and the distribution of the reflected electric field on the surface of the microprism.It then explores how the microstructure parameters of the LGP affect diffuse and specular reflection, as well as transmission. The study further compares the effects of the microscale ofhierarchical microlenses on micro-optical properties such as illuminance and uniformity with existing mar⁃ket solutions like screen-printed microdots and microprism arrays. Findings indicate that the reflected lightmonitoring surface for ultraviolet and blue light shows a smaller variation in the reflection electric fieldwhen the microlens aspect ratio is between 0.6-1, suggesting higher diffuse reflection. Experiments demon⁃strate that the hierarchical microlens array LGP, with microlens heights of 5-30 μm and microprismheights of 10-80 μm, can be produced in just 4 seconds. Illuminance uniformity improves as the microlensaspect ratio increases, with illuminance 45% and 83% higher than that of the microprism and screen-print⁃ed microdot, respectively. Moreover, compared to the microprism, the diffuse reflectance of ultravioletand blue light is 8% and 18% higher, respectively, and the mirror reflectance is 80% ⁃83% lower. Thus,controlling the aspect ratio of the hierarchical microlens can effectively reduce lighting glare and mitigatethe effects of ultraviolet and blue light.

关 键 词：复合微透镜阵列 热压印微成型 微光学性能 健康照明 

分 类 号：TH74[机械工程—光学工程] TN383.1[机械工程—仪器科学与技术]