Digital holographic microscopy has been widely adopted in the field of biology because of its ability of quantifying phase information. Unlike those conventional transmission-type phase imaging techniques, reflective digital holographic microscopy can be applied in the field of display industry or semiconductor industry for inspecting unwanted defects in a certain fabrication process. Consequently, it is necessary and required to achieve large field of view and resolution enhancement to meet the demands on the fast and accurate shape measurement. To increase the minimum resolution, we are going to adopt programmable illumination patterns by the use of fast-activating digital micro-mirror devices (DMDs) referring to Fourier ptychographic illumination. In this work, to expand space bandwidth product in reflection-type digital holographic microscopy (RDHM) configuration, we apply a fast-activating digital micro-mirror device for a amplitude-type spatial light modulator and a micro-lens array in the reference arm of a conventional RDHM.
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