×

Mura detection apparatus and method

  • US 5,917,935 A
  • Filed: 05/22/1996
  • Issued: 06/29/1999
  • Est. Priority Date: 06/13/1995
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method for detecting Mura defects on a substrate for a flat panel display, the method comprising the steps of:

  • a) acquiring an image of a first plurality of pixels in at least a portion of the substrate, the image including values of pixels from the first plurality of pixels;

    b) enhancing differences in the values of pixels in the first plurality of pixels to form an enhanced image, the enhanced image including values of pixels from the first plurality of pixels;

    c) thresholding the enhanced values of pixels from the first plurality of pixels to form a thresholded image, the thresholded image including thresholded values of pixels from the first plurality of pixels;

    d) identifying a second plurality of pixels from the first plurality of pixels corresponding to at least one blob within the thresholded image;

    e) identifying a third plurality of pixels from the first plurality of pixels corresponding to an annular region around at least one blob within the thresholded image;

    f) comparing values of the second plurality of pixels to values of the third plurality of pixels;

    g) determining a Mura defect in response to the comparison step.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×