Inicio  /  Applied Sciences  /  Vol: 10 Par: 13 (2020)  /  Artículo
ARTÍCULO
TITULO

Precision Auto-Focusing Apparatus Based on Long-Working-Distance, Wide-Spectrum Microscope

Chao Wang    
Tao Zhang and Weibo Wang    

Resumen

A mirror-based Schwarzschild microscope with a wide spectrum and a long working distance was investigated to perform precise assemblage of detectors. We employed a gradient square method to construct the evaluation function for realizing accurate quantitative analysis of image defocusing. By imaging a resolution target that corresponded to 228 line pairs per mm, the validity and imaging ability of the system was proven. The results of repeated focusing tests yielded a standard deviation of 0.75 µm, which indicated high performance accuracy for the focusing system. The proposed system has potential applications in industrial inspection and focusing detection.