Surface inspection apparatus, polarization illuminating device and light-receiving device
US7307725B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2005 |
| Grant date | Dec 11, 2007 |
| Priority date | — |
| Expiry date | Jul 6, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0636
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface inspection apparatus includes: a light source unit that emits a divergent light flux of predetermined linearly polarized light to be used to illuminate a test substrate; a first optical member that allows the divergent light flux of the predetermined linearly polarized light to enter therein with a predetermined angle of incidence and then guides a light flux to the test substrate; a second optical member that allows a light flux from the test substrate to enter therein, emits a convergent light flux thereof with a predetermined angle of emergence and forms an image at a specific surface; an extraction unit that extracts linearly polarized light in the convergent light flux from the second optical member, which is perpendicular to the predetermined linearly polarized light; a light-receiving unit that receives an image of the test substrate formed via the second optical member and the extraction unit; and at least one polarization correcting member disposed within a light path extending between the light source unit and the light-receiving unit, which corrects a disruption of a polarization plane attributable to the first optical member and the second optical member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.