Optical surface proximity measuring device and its application to the plotting of the profile of a surface
US4639140A · kind A · utility
29Cited by
7References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Feb 26, 1985 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Feb 26, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/028
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to an optical device for measuring the surface proximity and to its application in the plotting of a profile. The device comprises a radiation emitter forming a light spot on the surface and two detectors, which are sensitive to the light flux reflected by the surface. A pair of focusing elements having different focal lengths are associated with the detectors. The ratio between the signals supplied by the detectors is determined by a processing circuit. This ratio is used to calculate the distance independently of the angle of incidence of the incident beam and the reflection coefficient of the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.