Optical surface defect inspection apparatus and optical surface defect inspection method
US8547547B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2011 |
| Grant date | Oct 1, 2013 |
| Priority date | — |
| Expiry date | Dec 7, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0833
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention is to provide an optical surface defect inspection apparatus or an optical surface defect inspection method that can improve a signal-to-noise ratio according to a multi-segmented cell method without performing autofocus operations, and can implement highly sensitive inspection. The present invention is an optical surface defect inspection apparatus or an optical surface defect inspection method in which an inspection beam is applied onto a test subject, an image of a scattered light from the surface of the test subject is formed on a photo-detector, and a defect on the surface of the test subject is inspected based on an output from the photo-detector. The photo-detector has an optical fiber bundle. One end thereof forms a circular light receiving surface to receive the scattered light. The other end thereof is 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 cells for performing the inspection based on the outputs of the plurality of cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.