Fabrication of Multifocal Microlens Array by One Step Exposure Process

Abstract

Microlenses can be widely used in integrated micro-optical systems. However, in some special applications, such as light field imaging systems, multifocal microlens arrays (MLA) are expected to improve imaging resolution. For the fabrication of multifocal MLA, the traditional fabrication method is no longer applicable. To solve this problem, a fabrication method of multifocal MLA by a one step exposure process is proposed. Through the analyses and research of photoresist AZ9260, the nonlinear relationship between exposure dose and exposure depth is established. In the design of the mask, the mask pattern is corrected according to the nonlinear relationship to obtain the final mask. The continuous surface of the multifocal MLA is fabricated by the mask moving exposure. The experimental results show that the prepared multifocal MLA has high filling factor and surface fidelity. What is more, this method is simple and efficient to use in practical applications.

A Meniscus Multifocusing Compound Eye Camera Based on Negative Pressure Forming Technology

“…Compound eyes have the advantages of miniaturization, a large field of view, high integration, and high temporal resolution [ 1 , 2 , 3 , 4 ] that traditional optical systems cannot match. In recent years, researchers have developed a variety of compound eye processing technologies, such as photolithography, chemical etching, and two-photon polymerization [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. However, the development period of compound eye imaging systems has been comparatively short, and some technical obstacles are yet to be resolved, including low imaging resolution, and a production process that is long and complicated.…”