A Novel Fabrication Method for Forming Inclined Groove-Based Microstructures Using Optical Elements

Abstract

Backlight modules with inclined groove-based microstructures, such as V-cuts for liquid crystal display (LCD) applications, have been developed. This study presents a novel photolithography technology which utilizes an inclined exposure method. An inclined microstructure surface fabricated with a controlled optical path is exposed using refracted ultraviolet (UV) light. A weight-bearing point of inclined exposure uses an optical element prism which is placed between the UV light source and the photoresist. This approach utilizes a prism-based exposure which complies with Snell's law. Different from conventional photolithography, the angle needed and the smooth surfaces of microstructures fabricated using this approach can be easily controlled. The aim of this study is to fabricate inclined groove-based microstructures on optical film to form structures ranging from 30 to 90°. This research made use of microstructure plates with dimensions of 30×30 mm2 and with surface roughness less than 20 nm. The results from this study could provide an important foundation of knowledge for the fabrication of next-generation displays.