Automated Dimensional Analysis Using A Light-Sectioning Microscope

John Loomis, Allan Lightman, Allen Poe, Roger Caldwell, Thomas C. Bristow, Alson E. Hatheway
1989 Precision Instrument Design  
A computer vision system has been integrated with a modified light-sectioning microscope for the quality control and inspection of a machined part whose critical dimensions are in the range of 30 to 300 pm. Height measureinents were determined by analysis of the projected light-section line. Transverse measurements were made using the microscope in a traditional configuration with illumination from selected elements of an external LED ring array. The light section irradiance was under computer
more » ... ontrol to accommodate the spatial variations in surface reflectance whose dynamic range exceeded that of the vision system. Part features are located by the vision system. Edges and line centers are then measured to sub-pixel resolution with a gray-level analysis algorithm. This paper describes the design and operation of this system. Details of the measurement process and analysis algorithms are provided. ~ ~~ 'operated by E.G.LG. Mound Applied Technologies for the U.S. Department of Energy under contract no. DEACW88DP4396
doi:10.1117/12.950976 fatcat:fs7zdpl6u5b35g77km7wj3iqwm