Thermal deformation impacts on SOG Fresnel lens performance Free

Silicone-on-Glass (SOG) Fresnel lenses are flat optical elements used in concentrator photovoltaics (CPV). SOG lens production process broadly involves forming optical silicone prisms attached to glass. Silicone is first compressed onto glass while heat is applied in order to shorten its curing time. During the cooling process, however, difference between thermal expansion coefficient for silicon and glass causes thermal deformation of prisms which results in compromised optical efficiency. In this study, thermal-induced deformation of SOG Fresnel lens prisms is analyzed by Surface Profile Measurement (SPM) and Finite Element Analysis (FEA) methods. In order to better observe patterns of thermal deformation and overall lens performance, lens samples were subjected to an optical efficiency test. Focus quality (FQ) images were also taken and observed in order to further analyze thermally affected lens performance. The study is expected to contribute to knowledge on temperature induced performance determinants of SOG Fresnel lenses.