Method and device for the contactless measurement of movement
US4730929A · kind A · utility
Inventor
Key dates
| Filing date | Nov 20, 1985 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Nov 20, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method is indicated for the contactless measurement of the relative movement of an object (14) relative to a scannable pattern (12), a scanning beam (31) being generated which scans a portion of pattern which moves with the object along a scanning path on the pattern in order to produce a scanning signal. In order easily to be able to establish the angle between a reference direction rigid with the object and the direction of movement of the pattern in relation to the object, it is proposed that the scanning beam be displaced parallel with and/or pivoted along a curved guide path rigid with the object, the movement of the scanning beam occurring in accordance with a guide angle function and in that furthermore there is derived from the scanning signal a density signal which indicates the time pattern of the reciprocal value of the time interval between the scanning pulse at any given moment and the preceding scanning pulse, possibly averaged out and in that the phase location of the density signal is determined in relation to the guide angle function. The angle sought corresponds to this phase location.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.