Patents Represented by Attorney Han I. Sun
  • Patent number: 5909285
    Abstract: A part inspection and calibration method for the inspection of integrated circuits includes a camera to image a precision pattern mask deposited on a transparent reticle. Small parts are placed on or above the transparent reticle to be inspected. A light source and overhead light reflective diffuser provide illumination. An overhead mirror or prism reflects a side view of the part under inspection to the camera. The scene of the part is triangulated and the dimensions of the system can thus be calibrated. A reference line is located on the transparent reticle to allow an image through the prism to the camera of the reference line between the side view and the bottom view. A precise reticle mask with dot patterns gives an additional set of information needed for calibration. By imaging more than one dot pattern the missing state values can be resolved using an iterative trigonometric solution.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: June 1, 1999
    Inventors: Elwin M. Beaty, David P. Mork