Filter function-equipped optical sensor and flame sensor
US7361948B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2004 |
| Grant date | Apr 22, 2008 |
| Priority date | — |
| Expiry date | Mar 23, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/284
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In order to provide a filter device capable of maintaining stable optical characteristics for an extended period of time and to provide also a photosensor using the filter device, a photosensor having a filter function includes a filter device having a colored glass filter and configured for permitting transmission of light of a predetermined wavelength range including a detection target wavelength range and a light receiving device for receiving the light transmitted through the filter device. The filter device includes a first interference filter structure comprised of a plurality of light transmitting layers stacked on each other, the first interference filter structure being deposited on a face of the colored glass filter. The light receiving device includes a semiconductor photodetector structure having one or more semiconductor layers, a light receiving area being formed in the one or more semiconductor layers within the semiconductor photodetector structure. The one or more semiconductor layers forming the semiconductor photodetector structure contain InxAlyGa1-x-yN (0≦x≦0.21, 0≦y≦1).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.