Precision grating period measurement arrangement
US6304332A · kind A · utility
1Cited by
4References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 17, 2000 |
| Grant date | Oct 16, 2001 |
| Priority date | — |
| Expiry date | Feb 17, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A precision grating period measurement system uses a pair of properly positioned photodetectors to provide sub-Angstrom resolution. That is, the absolute position of a first detector with respect to a zero point in the measurement system is assured by including a second photodetector that measures a retroreflected signal. The system is then "zeroed" on the retroreflected signal such that the subsequent measurements recorded by the first photodetector are a precise measurement of the grating period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.