Fabrication of ball-strip convex microlens array using seamless roller mold patterned by curved surface lithography technique

Sung Wen Tsai, Yung Chun Lee

研究成果: Article同行評審

11 引文 斯高帕斯(Scopus)

摘要

Roller imprinting is one of the most commonly used methods for the fabrication of continuous functional structures over large areas. However, the trapped air between the roller and the imprint medium may result in the defects of the fabricated structures. Therefore, this study uses a curved surface photolithography technique to fabricate a seamless roller mold for a novel ball-strip microlens array in which the neighboring lenses are overlapped by a small distance in the rolling direction. When replicating microlens arrays using the patterned roller, the trapped air is squeezed out continuously in front of the roller as it advances over the imprint medium. As a result, the quality of the replicated lenses is significantly improved. The feasibility of the proposed approach is demonstrated by patterning a polyethylene terephthalate (PET) optical film with a ball-strip microlens array incorporating convex microlenses with a diameter of 58 m and a height of 20.5 m. The optical performance of the patterned PET film is evaluated by means of numerical simulations and a luminance inspection system. The simulation results show that the optimal luminance gain is obtained using a lens overlap of no more than 20%. Moreover, the experimental results indicate that the optical film yields a 30% improvement in the forward on-axis luminance compared to that provided by a standard white-light panel backlight unit and has a haze, total transmittance and diffuse transmittance of 94%, 95%, and 90.09%, respectively. Overall, the present results confirm the effectiveness of the proposed ball-strip design in improving the optical properties of microlens arrays fabricated via roller imprinting.

原文English
文章編號015014
期刊Journal of Micromechanics and Microengineering
24
發行號1
DOIs
出版狀態Published - 2014 一月 1

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Mechanics of Materials
  • Mechanical Engineering
  • Electrical and Electronic Engineering

指紋 深入研究「Fabrication of ball-strip convex microlens array using seamless roller mold patterned by curved surface lithography technique」主題。共同形成了獨特的指紋。

引用此