Position detecting device employing marks and oblique projection
US5162656A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1992 |
| Grant date | Nov 10, 1992 |
| Priority date | — |
| Expiry date | Mar 2, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7049
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A device for detecting positional relationship between a first and second objects in a predetermined direction is disclosed. The device includes light source for projecting light upon the first object so that the light incident on the first object is deflected thereby and emanates therefrom in a direction perpendicular to the predetermined direction; a light receiving portion disposed in a direction in which the light having been deflected perpendicularly to the predetermined direction and having been deflected again by the second object advances, the light receiving portion being operable to detect the position of incidence of the light thereupon, wherein the position of the light upon the light receiving means is changeable with the position of incidence of the light upon the second object; and a detecting system for detecting the positional relationship between the first and second objects in the predetermined direction, on the basis of the detection by the light receiving portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.