Athermal Optomechanical Design of a Camera Module for Minimizing Temperature Dependency

This study presents an optomechanical athermalization design for reducing the temperature-induced focus shifts in a digital side mirror (DSM) camera module. As DSM cameras operate in a wide range of temperatures, thermal changes in plastic lenses and mechanical structures can result in focus drift and image degradation. The focus shift sensitivity was used as a design parameter to mitigate these effects, and a mechanical compensation structure based on the thermal expansion of a holder was implemented. The proposed design maintained stable modulation transfer function performance at 120 lp/mm from -10℃ to 60℃. The experimental results confirmed that the focus shift and image degradation were suppressed across a wide temperature range. These results demonstrate that the proposed method can improve the thermal stability of various optical components.