Patent ID: 8948491
Filing Date: 2015-02-03
Classification: G01B,G01M,G01N

Abstract:
1. A method for detecting surface unevenness of an object under inspection, comprising: shooting a reflected image of slit lights, while moving the object under inspection relative to first and second illuminators, among a plurality of illuminators, for casting the slit lights at a target surface of the object and an image pick up for shooting the illuminated portion; detecting surface unevenness of the object under inspection based on respective luminance of the reflected image, wherein, in the shooting, the first illuminator casts slit light at a target surface of the object under inspection and the second illuminator casts slit light having a different wavelength from the slit light of the first illuminator simultaneously from a different direction than the first illuminator at the target surface of the object under inspection, and the image pickup shoots the reflected image of the portion illuminated by the slit lights, and wherein, in the detecting the surface unevenness, the reflected image is separated into the reflected images for mutually different wavelengths by image processing of the reflected image and luminance distribution waveforms for the separated reflected images respectively are obtained; and surface unevenness of the object under inspection is detected based on the obtained luminance distribution waveforms of the reflected images of the mutually different wavelengths.