Patent ID: 8842270

Claim:
A method of identifying whether a bright target spot on a polarizer is a bright spot defect or a glare spot, said method to be performed by an inspection device and comprising the steps of: obtaining gray values for pixels of an image of a detected region of the polarizer, the detected region containing the bright spot target; obtaining a gray value variation score from the gray values obtained for the detected region, the gray value variation score being indicative of gray value variation among the pixels of the image of the detected region; comparing the gray value variation score obtained for the detected region with a threshold value to obtain a comparison result, and determining whether the target spot is a bright spot defect or a glare spot according to the comparison result; and subjecting the gray values to an entropy algorithm so as to obtain the gray value variation score, the entropy algorithm being defined as: ∑ i = 0 L ⁢ p i × ln ⁡ ( p i ) where “L” is a predefined maximum gray value, “i” is an integer index number, “p i ” is a ratio of the number of pixels having a gray value of “i” to the total number of pixels in the image, and “E” is the gray value variation score.