Use of Nipkow disc to scan optically three-dimensional object in discrete parallel planes for computer resolution of contours

摘要

A light beam (10) shone through an aperture (13) in a rotating Nipkow disc (8) scans an object (4) in a succession of parallel planes (a-e). The images are resolved by computer to produce a three-dimensional representation of the object. Monochromatic or achromatic light is focused by the lens (9) to a point (11) in a plane (12) with a depth of focus (14) of a few microns. Light from the object is reflected only when the illuminated point is in line with the opening. By varying the distance between the measuring head and the object in discrete steps, a succession of parallel planes is scanned. The object illustrated (4) is a soldered joint to the connecting wire (5) between a microchip (2) and printed circuit board (1).