Wavelength determination using an optical filter having complementary transmission and reflection coefficients
US11333556B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 23, 2017 |
| Grant date | May 17, 2022 |
| Priority date | — |
| Expiry date | Nov 1, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2009/0226
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus and associated methods relate to determining the wavelength of a narrow-band light beam. The narrow-band light beam is passed through an optical filter. The optical filter has complementary and monotonically-varying transmission and reflection coefficients within a predetermined band of wavelengths. The predetermined band of wavelengths includes the wavelength of the narrow-band light beam. A first photodetector detects amplitude of a first portion of the narrow-band light beam transmitted by the optical filter. A second photodetector detects amplitude of a second portion of the narrow-band light beam reflected by the optical filter. The wavelength of the narrow-band light beam is determined, based on a ratio of the determined amplitudes of the first and second portions of the narrow-band light beam transmitted and reflected, respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.