Optical unit
US8570510B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 2010 |
| Grant date | Oct 29, 2013 |
| Priority date | — |
| Expiry date | Jul 28, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/4244
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical unit has a filter member that disperses transmitted light and a photodetector that has light receiving elements. The filter member has a light transmissive substrate, protrusions including a first metallic material and formed on one surface of the substrate, and a metal film including a second metallic material having a refractive index higher than that of the first metallic material and formed so as to cover the protrusions as well as the one surface of the substrate. The metal film located between adjacent protrusions can be a diffraction grating and the protrusions can be waveguides. At least one of the grating cycle of the diffraction grating, the height of the protrusions, and the thickness of the metal film is set to a value different for each portion such that a wavelength of light transmitted through the filter member changes for each portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.