以雷射3D列印技術製備微米光學擴散結構

Fabrication of Diffuser Film with Microlens Arrays by Laser 3D Printing

林家安(Chia-An Lin)

指導教授 ： 李有璋

中原大學/工學院/機械工程研究所/碩士(2021年)

https://doi.org/10.6840/cycu202100782

摘要

本研究透過提升立體光固化設備曝光解析度以製作出具有微透鏡陣列結構的3D列印模型，接著利用壓印技術轉印微透鏡陣列結構並分析微透鏡陣列結構的光學擴散性能。
為了達到列印微透鏡陣列結構的需求，本研究首先透過光路校正模組提升立體光固化設備的曝光掃描解析度，再利用自行編寫的數值化加工路徑生產程式改善加工指令與電機之間的相容性。以此將立體光固化設備的列印條件提升至足以列印微透鏡陣列結構的精細度。
製程方式首先運用參數化的數值化模型建立加工路徑，再利用自行建置的光固化立體設備進行曝光列印，即為完成微透鏡陣列結構的3D列印樹脂模型。在得到立體微透鏡陣列結構樹枝模型之後，本研究使用翻模與熱塑性樹脂熱壓印的方式對微透鏡陣列結構進行複製轉印。
壓印製程所需的模具為3D列印微透鏡陣列結構使用PDMS灌注而成。本研究觀察PDMS模具對熱塑性材料進行熱壓印製程的相關參數對結構完整性之影響，並增加熱處理製程改善微透鏡陣列結構表面精細度以提升擴散片之光學性能。最後以雷射投影的方式搭配光學影像分析軟體檢測微透鏡陣列擴散片的光學擴散性能，並以添加結構隨機度的方式影響該擴散元件的光束整形能力。

關鍵字

立體光固化

並列摘要

This study developed a high-resolution 3D stereolithography apparatus (SLA) to fabricate the imprinting molds of the microlens array. The molds were used to fabricate the microlens-array diffusers by imprinting technique and analyzes their optical performance.
To reach the scale requirement of microlens-array structure, the study first enhanced the resolution of stereolithography apparatus through using optical correction module. On the other hand, numerical programming for processing plan was used to improve the compatibility between processing commands and actuation devices. Parameterized numerical model was used to build the processing path.
The epoxy mold of microlens array was fabricated by the SLA with the UV laser of wavelength 405 nm. A flexible PDMS (Polydimethylsiloxane) mold was used to duplicate the epoxy mold for a thermal embossing process to fabricate the microlenses. Heat treatment was used to improve the surface smoothness of the imprinting microlenses. The performance of optical diffusing for microlense array with various random distribution of imprinting microstructure were investigated by a red laser of wavelength 633 nm.

並列關鍵字

3D print

參考文獻

[1] S. Song, Y. Sun, Y. Lin, B. You, “A facile fabrication of light diffusing film with LDP/polyacrylates composites coating for anti-glare LED application”, Applied Surface Science, Vol 273, 652-660, 2013

[2] H. P. Kuo, M. Y. Chuang, C. C. Lin, “Design correlations for the optical performance of the particle-diffusing bottom diffusers in the LCD backlight unit”, Power Technology, Vol. 192, 116-121,2009

[3] W. Wang, J. Fang, K. Varahramyan, “Compact variable-focusing microlens with integrated thermal actuator and sensor”, IEEE Photonics Technology Letters, Vol. 17, 2643-2645, 2005

[4] R. H. Anderson, “Close-up imaging of documents and displays with lens array”, Applied Optics, Vol. 18, 477-484, 1979

[5] R. Volkel, H.P. Herzig, P. Nussbaum, R. Dandliker, “Microlens array imaging system for photolithography”, Optical Engineering, Vol.35, 3323-3330, 1996