Photoconductive bolometer infrared detector
US7262413B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Mar 14, 2005 |
| Grant date | Aug 28, 2007 |
| Priority date | — |
| Expiry date | Jul 31, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A photoconductive bolometer infrared detector using a detector material that has a resistance changed due to photo-excitation and thermal-excitation from an incident radiation in the infrared range. The resistance changes caused by photo-excitation and the thermal excitation are additive for this detector material. The detector material is suspended over a substrate by a gap of one quarter wavelength of the incident radiation, such that the thermal absorption of the incident radiation can be enhanced. Preferably, the detector material is lead selenide that has a thermal coefficient of resistance as high as 3.45%° C.−1, which is about 60% higher than that of vanadium oxide that has been widely used as the detector material in the conventional microbolometers. This detector structure allows dual band uncooled or moderately cooled operation. In the case of the use of PbSe as the detector material, largely enhanced MWIR operation is enabled over a standard uncooled micro-bolometer tuned to the LWIR, and high temperature dual band MWIR and LWIR operation is enabled as compared to quantum well or HgCdTe detectors that must be cooled to cryogenic temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.