Method of measuring the amount of movement of an object having uniformly periodic structure
US4823001A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 17, 1987 |
| Grant date | Apr 18, 1989 |
| Priority date | — |
| Expiry date | Aug 17, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/38
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An object to be measured for the amount of movement thereof has a uniformly periodic structure. The object is illuminated with divergent light emitted from a coherent spot light source. By positionally adjusting the spot light source, the object, and a light sensor, an enlarged shadow-picture-like diffraction pattern of the uniformly periodic structure is generated at a position in which the light sensor is disposed. The shadow-picture-like diffraction pattern is moved when the object is moved across the divergent light from the spot light source. The amount of movement of the shadow-picture-like diffraction pattern is detected by the light sensor for thereby measuring the amount of movement of the object.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.