Fabricating microlens arrays using moving mask projection lithography

Microlenses are important micro-optical components with functions such as laser collimation, focusing, and homogenization. They are widely used in various fields such as laser communications, fiber optics sensing, laser radar ranging, and laser pumping. The traditional manufacturing process of microlens array has the problem of low precision, low efficiency, high cost, and can not guarantee high surface profile accuracy. In this paper, a moving mask projection lithography process for manufacturing microlens arrays is proposed, in which a 0.2x projection objective is used to improve the linewidth resolution. We use mask shift filtering technology based on projection lithography to reduce the complexity of mask preparation and obtain higher surface profile accuracy.