Device for detecting positional relationship between two objects
US5327221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1992 |
| Grant date | Jul 5, 1994 |
| Priority date | — |
| Expiry date | Jul 29, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7049
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A device for detecting the positional relationship between first and second objects in a predetermined direction includes a light source for emitting light in a direction to the first or second object, and a first detecting portion for detecting the position of incidence of a first light deflected by the first and second objects, wherein the position of incidence of the first light upon the first detecting portion is changeable with a change in the positional relationship between the first and second objects in the predetermined direction. A second detecting portion detects the position of incidence of a second light deflected by at least one of the first and second objects, wherein the state of the position of incidence of the second light resulting from a change in the positional relationship between the first and second objects, in the predetermined direction differs from that of the first light. On the basis of the detection by the first and second detecting portions, the positional relationship between the first and second objects is detected without being affected by an inclination thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.