Programmable In-Situ Interactions Between Resins and Photopolymerized Structures for Seamlessly Integrated Optical Manufacturing of Microlenses

Abstract

Photopolymerization is typically used to directly create solid structures by controlling light irradiation onto liquid resins. However, this approach lacks the ability to accommodate three-phase interactions within the resin, which could otherwise be harnessed to carve curvilinear structures in a programmable manner. Here, we present an opposite strategy that induces resin interactions by embedding in situ photopolymerized confinement, enabling a highly integrated and seamless optical workflow for the manufacturing, characterization, and qualification of microlenses. In our demonstration, spatiotemporally controlled, multiplexed ultraviolet exposure locally solidifies photocurable resins outside the regions of interest, leading to the spontaneous development of concave curvatures in the unexposed liquid domains through programmable three-phase interfaces. This curvature evolution is quantitatively tracked in real time via in situ pinhole image analysis and can be fixed by short light exposure to preserve the targeted lens geometry. Furthermore, we present an intensity-compensation algorithm to resolve spatial non-uniformities in optical writing setups, thereby yielding microlens arrays with high uniformity. Finally, we demonstrate in situ qualification of microlenses across different fabrication batches, where pinhole images are quantitatively analyzed and tracked to assess batch-to-batch consistency. Our seamlessly optically integrated workflow with in situ interactions would be helpful in designing setups for other optical components toward curvilinear structures, in situ photopolymerization, microlens arrays, optically integrated processes and advanced applications.