Abstract：In parallel confocal measurement, the optical divide devices (ODDs) are used to divide the incident light into lots of beams; however, the parameters of ODDs are fixed, which cause bad adaptability to different measured objects. As digital micromirror device (DMD) was introduced into parallel confocal measurement, the point light array, which is very important in parallel confocal measurement, could be designed flexibly to be applied in different measuring situations.A spatial light modulation model of DMD was deduced, and this model indicated that “Talbot Effect” would not influence the parallel confocal measurement. A telecentric optical path was introduced to restrain the drift of point light array, and then a parallel confocal measurement device based on DMD was established; two kinds of image processing were proposed and compared, and the experiment results indicated that, the axial resolution was affected without objective lens group of high numerical aperture, however the surface topography of specimen could be acquired quickly and accurately by the designed image processing.
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2015, Vol. 36 
