Patent ID: 8547547
Filing Date: 2013-10-01
Classification: G01N

Abstract:
1. An optical surface defect inspection apparatus comprising: an irradiating unit configured to irradiate an inspection beam onto a test subject; a scattered light optical system configured to form an image of a scattered light from a surface of the test subject on a photo-detector; and a processing unit configured to inspect a defect on the surface of the test subject based on an output from the photo-detector, wherein: the photo-detector includes an optical fiber bundle having one end thereof forming a circular light receiving surface to receive the scattered light, and the other end thereof connected to a plurality of light receiving devices; the optical fiber bundle is divided into a plurality of fan-shaped cells in the light receiving surface, and connected to the light emitting devices in units of the fan-shaped cells; a number of the cells is an even number; and paired cells provided at positions opposite to each other are connected to a same light receiving device.