Measurement of waveplate retardation using a photoelastic modulator
US6738137B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 2, 2002 |
| Grant date | May 18, 2004 |
| Priority date | — |
| Expiry date | Oct 2, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/23
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A practical system and method for measuring waveplate retardation. The system employs a photoelastic modulator in an optical setup and provides high sensitivity. The analysis is particularly appropriate for quality-control testing of waveplates. The system is also adaptable for slightly varying the retardation provided by a waveplate (or any other retarder device) in a given optical setup. To this end, the waveplate position may be precisely altered to introduce correspondingly precise adjustments of the retardation values that the waveplate provides. The system is further refined to permit one to compensate for errors in the retardation measurements just mentioned. Such errors may be attributable to static birefringence present in the optical element of the photoelastic modulator that is incorporated in the system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.