Using a digital micromirror device for three dimensional microinspection
Although Digital Micromirror Devices (DMD) have recently been used mainly for image- and video-projection, they can also be applied in the field of optical metrology. This paper demonstrates the use of a DMD in a confocal microscope as flexible scanning device where a set of DMD based virtual pinholes are used to substitute e.g. physical pinholes on a conventional Nipkow disk. First, it illustrates the fundamentals of confocal microscopy and DMD technology and then shows how these two fields of technology can be combined. The principle setup of the newly designed instrument is presented and first results achieved with it are shown and compared with the classical physical pinhole approach.