Optically detecting defects in transparent object

Abstract

The present invention relates to a method of detecting defects in a transparent optical material, comprising the steps of: providing a digital image having a plurality of image pixels of a transparent material, and at least one candidate defect detection. Candidate defect can be detected through the following operation, i.e., determining the gray scale intensity of each image pixel and the adjacent pixel across the gradient strength calculated. Assigned to each image pixel gradient values, including a maximum of absolute values ​​of the intensity gradient associated with image pixels. Gradient image may be constructed, comprising the corresponding image pixel is assigned to the gradient values. If the gradient value exceeds a gradient threshold pixel value, the image pixels may be identified as a candidate pixel. It may include an optical defect candidate pixels.