A previewing profiler includes apparatus to scan the surface of an object and to provide a display relating to the smoothness of the surface at a microscopic level. The system includes providing a polarized collimated laser beam through a Nomarski type prism and focusing the resulting beams on the surface to be scanned. The system further includes a user operable rotatable mirror which may be inserted, upon operator command, between the laser and Nomarski prism, which mirror is designed to leak a small percentage of the laser light. Another source of noncollimated polarized light, provided through a condensing lens, is provided to the rotatable mirror to be directed along the same path through the Nomarski prism and to be focused at a point above the surface being scanned, thereby providing a substantially larger illuminated area on the surface. The reflected light from both the laser beam and additional noncollimated light is focused on a CCD array and then displayed on a display. This permits the user to view the area to be profiled, including the profile line, prior to operating the profiler.