Phase defect detection of large-aperture optics with static multiplanar coherent diffraction imaging

• DOI: 10.1364/ao.388185
• Publication Date: 2020-04-06T16:30:07Z
• Authors: Hongchang Wang; You Li; Zhaoyang Jiao; Junyong Zhang; Mingying Sun; Jianqiang Zhu
• Keywords: Coded aperture; Aperture (computer memory)

Phase defect detection with micrometer scale on large aperture optical elements is one of the challenges in precision systems. An efficient scheme proposed to detect phase defects. First, defects are positioned a by dark-field imaging based photon sieves improve efficiency relatively low cost. Second, static multiplanar coherent diffraction used retrieve small field view. Here, spatial light modulator as multifocal negative lens eliminate mechanical errors imaging. The use instead positive has advantage larger space for system configuration. Compared traditional interferometry system, this simpler path and doesn't require sparse distribution Experiment results demonstrate success resolution better than 50 µm. We believe work provides an effective method rapidly optics high accuracy resolution.