Automatic contaminants detection apparatus
US4614427A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 18, 1984 |
| Grant date | Sep 30, 1986 |
| Priority date | — |
| Expiry date | May 18, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/956
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An automatic contaminants detection apparatus comprises a polarized laser beam source, a polarized laser beam irradiation optical system having irradiation angle switching means for switching an irradiation angle depending on the presence or absence of a pattern on a sample surface to irradiate the polarized laser beam emitted by the polarized laser beam source to the sample surface with an angle of grazing, a detector for detecting condensed scattered or reflected lights of the laser beam from the sample surface with or without interleave of an analyzer, and analyzer switching means for inserting or removing the analyzer into or from a detection light path of the detector depending on the presence or absence of the pattern on the sample surface. The apparatus can detect contaminants on the patterned or non-patterned sample surface with a high sensitivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.