Surface inspection method and apparatus
US5694214A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1996 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Dec 18, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/8851
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface inspection apparatus of the present invention comprises an optical sensor having a plurality of detecting portions arranged in a sub-scan direction, the detecting portions being responsive to the scattering light for producing the detection signals correspondingly to respective pixels, a detection optical system including an objective lens and disposed between the optical sensor and the thing to be inspected, a projection optical system for irradiating the thing to be inspected with the laser beam having a cross sectional area large enough to cover the scattering light to be received by the plurality of the detecting portions through the detection optical system and an inspection device responsive to the detection signals for inspecting the surface of the thing to be inspected, wherein one of the detection optical system lens and the optical sensor is mounted such that a setting axis thereof is aligned in a plane perpendicular to an optical axis of the detection optical system lens with a light receiving direction which makes an angle with respect to the sub scan direction and in which shading is minimum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.