Tolerance Analysis and Desensitization to Parallelism in Afocal Systems of Fabry-Perot Spectrometers

Existing research on Fabry-Perot (FP) spectrometers lacks tolerance analysis and desensitization for the parallelism of afocal systems, leading to scenarios where, despite afocal systems being satisfactory in design, their parallelism deteriorated during actual production. Therefore, this letter proposes a tolerance analysis and desensitization optimization method for the parallelism of afocal systems applied to FP spectrometers. By creating multiple zooms, we can intuitively analyze the impact of each tolerance on parallelism, and perform desensitization optimization of parallelism based on the characteristic angle changes dictated by the FP etalon. Utilizing this method, we conduct a tolerance analysis and desensitization optimization of parallelism for afocal systems, achieving a parallelism-insensitive afocal system and verifying the effectiveness of the method.