Design and Fabrication of the Bidirectional Micro-Optic Concentrator for Optical Radiation

Abstract

This paper presents the design and fabrication of a micro-optic concentrator for optical radiation based on coupled micro-lenses and micro-prism (micro – mirrors) arrays. This type of micro-optic concentrator is suitable for both terrestrial and spatial applications where optical radiation is redirected and coupled to small area photovoltaic cells or detection devices located in front of the waveguide edges. Analysis and design were performed for the 0.4-1.06µm spectral range using the COMSOL Multiphysics program and the Ray Optics geometric optics module. Simulations for ray-tracing have been modeled in order to optimize the geometries of micro-optics elements taking into account the optical parameters of the materials to be used (polymers and glass) in the process of micro-optic concentrator fabrication. Micro-lenses and micro-prism arrays were fabricated by the technique of molding in silicon molds and replication in polymeric materials using OrmoClear30 elastomer (n=1.56, UV exposure) and in UV-PDMS, KER4690 polymer, respectively. Assembling and the fabrication process of micro-optic concentrator allowed the achievement of an optical efficiency of 70 % efficiency.