Method and apparatus for measuring a relative movement between two elements
US5541732A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 24, 1995 |
| Grant date | Jul 30, 1996 |
| Priority date | — |
| Expiry date | Feb 24, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P3/806
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
For measuring an amount of relative movement between two elements, such as a vehicle and a track, which are mutually movable, two successive pulses of coherent light are directed from the vehicle to the track under a same incidence angle. From a same location of the vehicle, two images of the interference patterns due to the short pulses are formed. The two pulses are offset from each other in the direction of movement by a distance d approximately corresponding to the amount of relative movement between the two pulses. The actual amount of movement is computed as being the movement which provides the best coincidence between the two images. The comparison can be made by cross-correlation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.