Athermalization of a lens system by glass selection using simulated annealing with memory augmentation

Abstract

In contrast to the current athermal map's lack of intuitiveness, we introduce a novel composite athermal map to visually evaluate the potential of lens system glass materials in achieving athermal and achromatic designs. Furthermore, unlike graphically manual methods for athermalization, we propose an automatic method to athermalize the optical system by glass selection using simulated annealing with memory augmentation (GlaSAM). This method employs a comprehensive objective function that integrates thermal aberration, chromatic aberration, secondary spectrum aberration, and Petzval curvature aberration. Weight factors are introduced to evaluate each aberration in the function, and filters are applied to streamline the search space. Additionally, the augmentation of memory into the optimization algorithm not only enhances its efficiency but also safeguards against overlooking solutions with superior imaging quality. To test the advantage of the GlaSAM method, a complex telephoto design is optimized to function across a temperature range from -40°C to 70°C, and the results demonstrate the efficacy of athermalizing the lens system while preserving exceptional imaging performance through this proposed method.