Precision optical distance measurement
US4309618A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1980 |
| Grant date | Jan 5, 1982 |
| Priority date | — |
| Expiry date | May 5, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are shown for precision distance or displacement measurement using a light source and a detector. A light emitting diode or laser are typical sources, and a photodiode or phototransistor are typical detectors. Light from the source is directed towards the detector directly, or reflected onto the detector by a reflective surface. By tilting the axis of the light source and detector, high sensitivity is possible. The effect of the tilted axes may be obtained by the use of two reflective surfaces. Typical resolution is on the order of 5 microinches over a range of 50,000 microinches (i.e., one part in 10.sup.4) using simple associated electronics, with higher resolution possible.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.