Tight tolerances for large-volume precision-pressed plastic optics (COMPAS)

Abstract

Ultra-precision molded polymer optics range from high precision imaging objectives to tiny lenses like those used in camera modules for cell phones, where centration tolerances and filling of small features is a challenge. We propose a manufacturing process termed Compression Molded Polymer Aspheres (COMPAS). Polymer preforms are inserted into mold cavities, and isothermally heated above glass point. Novel tooling has been developed to produce high volumes of COMPAS optics at reasonable cost and cycle time, using large scale parallelization of mold cavities. First results of the COMPAS process are very encouraging: shape accuracy (<500 nm peak-to-valley), surface centration (<5 μm), and birefringence (<20 nm/cm) are well below values typically measured for injection molded lenses. COMPAS lenses are also gate free. We describe details of the on-axis turning of arrays and multi-cavities (DPI) and the COMPAS precision polymer molding process. We describe the metaphysical background of disruptive engineering based on physical principles, which is the reason behind developing DPI and COMPAS.