Single-Snapshot Focus Variation Microscopy for High-Speed Topographic Optical Imaging

Abstract

Focus variation microscopy (FVM) enables non-contact, three-dimensional measurements on the micro- and nano-scales, which are crucial in applications such as precision engineering and machining process control. Here, we report single-snapshot focus variation microscopy (S-FVM), which improves acquisition speed and reduces data bandwidth by capturing compressed images. Moreover, we use structural complementary masks for encoding to obtain high-quality and stable demodulated images. The acquired compressed images effectively preserve the optical information, owing to the inherent periodic ordering characteristics of the structural complementary masks. The fast topographic imaging capability of S-FVM was experimentally confirmed by measuring samples containing machined. This work provides a potential solution for high-speed topographic imaging.