A novel fabrication method of the micro cube beam-splitter with optical surface roughness

This paper successfully used inclined exposure technology to fabricate 50/50 3D micro cube beam splitter with 45° optical grade surface (~1.4 mm thick). This paper tests the effect of solvent loss percentage of the polymer material (optimum surface roughness: 85.45% solvent remove) on the surface roughness of inclined surfaces. The smallest surface roughness achieved in the experiments using SU-8 material with a thickness of 1.4 mm was less than 70 nm (400μm × 400μm area). This type of micro-mirror can be used as a key component in Michelson Interferometer, bio detection systems, data storage system and linear encoder.