Position detection method and apparatus
US5114236A · kind A · utility
64Cited by
11References
52Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1990 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Aug 3, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7076
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A position detecting method for detecting the position of a substrate by use of a grating pattern provided on the substrate includes irradiating the grating pattern with first and second radiation beams having different wavelengths to produce first and second diffraction beams of different wavelengths; and receiving the first and second diffraction beams by use of a sensor to determine the position of the substrate on the basis of the position of incidence of each of the first and second diffraction beams on the sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.