Detecting the presence or absence of a coating on a substrate
US4456374A · kind A · utility
14Cited by
2References
25Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 11, 1981 |
| Grant date | Jun 26, 1984 |
| Priority date | — |
| Expiry date | Dec 11, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/86
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus is provided for determining the presence or absence of a coating on a substrate. The substrate is placed into optical contact with a light guide and the principle of frustrated total internal reflection is utilized. Light scattered from the coating surface is monitored to indicate the presence of a coating and failure to detect scattered light indicates the absence of said coating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.