Thermal detection arrangement having a plurality of optical filter devices
US5162658A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1991 |
| Grant date | Nov 10, 1992 |
| Priority date | — |
| Expiry date | Apr 22, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B17/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A thermal detector arrangement includes a number of channels, each including a collimator for collimating incident radiation to a respective optical filter. Each optical filter has a respective radiation passband characteristic with one having a passband spanning the passbands of all of the other optical filters. The radiation passed by each optical filter is passed to a thermal detector, which preferably is in the form of a thermally isolating membrane acting as a radiation absorbent cavity and supported by a semiconductor substrate. The output signals from the thermal detectors are multiplexed, amplified by an amplifier having voltage offset compensation and digitally processed to provide an indication of a fire to be sensed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.