Diffraction grating position adjuster using a grating and a reflector
US4656347A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1985 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Jan 28, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7049
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of adjusting a relative positional relationship between two objects uses a diffraction grating. A first diffraction grating is arranged on a first object located to oppose a second object, a reflecting surface is arranged at a position of the second object which corresponds to the first diffraction grating, and the method includes the step of irradiating the first diffraction grating with a radiation beam of coherent light or quasi-monochromatic light and measuring/setting the gap between the first and second objects in accordance with a change in intensity of one of the diffracted light components from the first diffraction grating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.