Method for no-contact measurement
US3989378A · kind A · utility
Inventors
Key dates
| Filing date | Jun 19, 1974 |
| Grant date | Nov 2, 1976 |
| Priority date | — |
| Expiry date | Jun 19, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/36
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method for no-contact measurement of the relative velocity, position, or displacement path of objects without special optical markers with respect to a reference position in at least one coordinate direction, or of the degree of image quality of an image wherein the apparatus images the object on a grating and the light fluxes leaving this grating are measured by means of photoelectric elements. The output signals of the photoelectric elements exhibit a frequency component proportional to the velocity of travel. The present invention is distinguished from the prior art by having a physical beam splitter (6,13) inserted in the imaging beam path in front of the grating (5,14), and preferably several polarizing beam splitters (7,30-33) with at least respectively one associated photoelectric receiver pair (10,11,16-19 16'-19') are connected after the grating (5,14).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.