Patent ID: 6349145
Filing Date: 2002-02-19
Classification: G01M

Abstract:
A method for inspecting an optical member to be inspected, in which light emitted from a light source is diffused by a diffusing means, before being made incident on said optical member, light emitted from said optical member being picked-up by an image pick-up means, said diffusing means comprising a central portion and a peripheral portion, a diffusion transmittance of said peripheral portion being higher than that of said central portion, wherein said method comprises:a first process to input an image including an image of said optical member from said image pick-up means; a second process to binarize said input image and execute a preliminary separating operation in which said image of said optical member is roughly separated from said input image according to a luminance distribution of said binarized input image; a third process to judge whether or not said preliminary separating operation has been successfully executed in said second process; a fourth process to execute a main separating operation in which an image to be inspected is separated from said roughly separated image of said optical member; and a fifth process to binarize said separated image to be inspected that is separated in said main separating operation, and judge whether or not said optical member is defective, wherein said fourth and fifth processes are performed only when it is judged in said third process that said preliminary separating operation has been successfully executed in said second process.