Study on the Fabrication of Fresnel Lenses with Roll-to-Roll Process

• Main Authors: Yu-Jyun Lin, 林育駿
• Other Authors: Min-Wen Wang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/27501512291944865999

碩士 === 國立高雄應用科技大學 === 機械與精密工程研究所 === 98 === This study is devoted in developing Roll to Roll (R2R) fabrication of microstructures of Fresnel lens. The R2R fabrication process has the advantages in fast and mass replication of microstructures, and it is a good fit for fabricating devices based on flexible substrates. When fabricating high aspect ratio micro features or special shape micro features such like Fresnel lens, interference can occur in the demolding process. Therefore, the aim of this study was to investigate the possiblity of interfence when making Fresnel lenses using Roll-to-Roll proces. This study is divided into two parts, the first part is to design the curvatures of the the Fresnel lens, to make of the lens stamper with Ultra-Precision Manufacturing Technology (UPMT), and finally to fabricate and investigate the Roll-to-Roll process on making Fresnel lens. The optical design presented in this study demonstrated that combination of thin lens formula and principles of Fresnel lens can be applied to design non-imaging Fresnel lens. On the making of Fresnel lens roller stamper, the unevenly distribution of the microstures on the Fresnel lens likely will casue warping using electroforming process, and it is better to carve the Fresnel lens microstures on a roller directly if possible.The experimental results showed that interference caused by the force induced in the demolding process, and it only happened at the exiting end of the Fresnel lens. The interference caused the peeling between UV resin and the PET substrate while the shapes of the Fresnel microstructures were kept intact. The second part of this study was to duplicate a PDMS stamper from a commercial Fresnel lens product and carry out the Roll-to-Roll fabrication of the Fresnel lens experiment using the PDMS stamper. To provide uniform pressure distribution and prevent the PDMS stamper from break, the PDMS stamper was wrapped around the steel roller completely. But PDMS stamper has short molding life, so it is not suit for long time experiemnts. The experiment results indicated that PDMS was not suitable for the study of interference problem in roll-to-roll process, and also implied that PDMS stamper was suitable for the production of products which have microstructures with interference by Roll-to-Roll fabrication.