Process and device for the contact free determination of the movement of an object
US4616931A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 7, 1983 |
| Grant date | Oct 14, 1986 |
| Priority date | — |
| Expiry date | Nov 7, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P3/36
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An image of a moving object with an optically differentiatable structure is projected onto a grid of opto-electric transducers through a lens. The output signals of at least one square group of four transducers A-D are processed to produce from output signals of the respective transducers a pair of signals I=A+B-C-D and II=B+C-A-D. The nature of the object is such as to cause periodically varying signals in the transducers, and there are thus concerned two signals shifted by a quarter period, from which the direction of movement can be determined by means of a logic circuit. From the frequency of the signals the velocity can be ascertained. By means of direction dependent counters the path of the object can be determined from the signals. With a two dimensional matrix of transducers measurements can be effected of movement of the object in different directions. The measurement is simple and offers versatile possibilities of exploitation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.