The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 29, 1999
Filed:
May. 22, 1996
Jeffrey A Hawthorne, San Francisco, CA (US);
Joseph Setzer, Pleasanton, CA (US);
Photon Dynamics, Inc., San Jose, CA (US);
Abstract
A method and apparatus for identifying and classifying pixel defects, and in particular Mura defects using digital processing techniques. The present method includes steps of acquiring an image with a Mura defect, and performing a Laplacian convolution on the image to enhance the Mura defect against background illumination. A step of thresholding the Mura defect against the background illumination is also provided. The thresholded Mura defect is compared against the original Mura defect to define statistical parameters of the original Mura defect. An annular region is defined around the periphery of the Mura defect. Statistics of the annular region defines statistics for background illumination as compared to the original Mura defect. The statistics from the Mura defect are then compared to the background illumination statistics for Mura defect classification and analysis.