Confocal microscopy is a powerful tool that has been used in the development of 3D profilometers for depth-section image capture and surface measurements. Previously developed confocal microscopes operate by scanning a single point, or array of points, over the surface of a sample. The 3D profilometer we constructed acquires measurement data using a confocal microscopy technique, where transverse surface (x, y) scanning is performed by a digital micromirror device (DMD). The DMD is imaged onto the object's surface allowing for confocal surface scanning of the field of view at a rate faster than video rate without physical movement of the sample. 3D reconstruction is performed a posteriori from stacks of 2D image planes acquired at different depths. A description of the experimental setup with system design issues and solutions are presented. Backscatter noise and diffraction noise due to the periodic micromirror structure is minimized using spatial filtering and polarization coding techniques. Using a lOOx objective, the longitudinal point spread function (FWHM) was measured at 2. 1 rim, with simultaneous transverse resolution of 228.0 lines/mm. The optical resolution performance of our microscope with real-time scanning provided by the DMD, is shown to be effectively equivalent to those of conventional confocal microscopes. The 3D image capabilities of our scanning system using the DMD were demonstrated on various objects.

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There is a growing need for developing 3-D quantitative imaging tools that can operate at high speed enabling realtime visualization for the field of biology, material science, and the semiconductor industry. We will present our 3-D quantitative imaging system based on a confocal microscope built with a Texas Instruments Digital Micromirror Device (DMD). By using the DMD as a spatial light modulator, confocal transverse surface (x, y) scanning can be performed in parallel at speeds faster than video rate without physical movement of the sample. The DMD allows us to programmably configure the source and the detection pinhole array in the lateral direction to achieve the best signal and to reduce the crosstalk noise. Investigations of the microcirculation were performed on 40 g to 45 g golden Syrian hamsters fit with dorsal skin fold window chambers. FITC-Dextran or Red blood cells from donor hamsters, stained with Celltracker CM-DiI, were injected into the circulation and imaged with the confocal microscope. We will present the measured results for the axial resolution, in vivo, as well as experimental results from imaging the window chamber.