Parallel large-range scanning confocal microscope based on a digital micromirror device

Abstract

A multi-point parallel large-range confocal microscope was designed and developed based on a digital micromirror device (DMD). Operated with specific patterns, the DMD can transform a single light source into multiple beams. The DMD functions as a virtual pinhole array and takes the place of traditional pinholes to realize parallel lateral scanning The DMD based confocal system can achieve parallel scanning in the case of ensuring axial resolution with high axial resolution. In that way, it can not only increase the inspection speed, but also safeware control the key parameters of the system, such as pinhole size and geometry. Interference patterns duo to reflections at the inner surfaces of the beamsplitter cube were eliminated, and a transverse scanning strategy was developed. In order to characterize the system, the depth response curves were acquired and finally the three-dimensional images of the target object was successfully reconstructed with a uncertainty of about 0.5%.