IR sensor with reflective calibration
US6369386B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1999 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Apr 7, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/53
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A self-calibrating infrared (IR) sensing device having the capability to measure the attenuation effects of surface contamination on the transmission window and to adjust the gain of the sensor accordingly so as to counter the attenuation. The IR sensing device includes an IR sensor mounted in a housing having an IR transparent window that allows IR radiation originating from outside the housing to be directed toward the sensor. The IR sensor includes a thermally isolated area of IR-absorbing material coupled to a temperature measuring unit. IR radiation impinging on the sensor is absorbed, thereby raising the temperature of the IR absorbing material. The temperature measuring unit measures the increase in temperature and generates a proportional electronic signal indicative of the temperature. The electronic signal is received and processed by a processor. An IR radiator is also included within the sensing device housing. When activated, the radiator emits IR radiation that passes through the window and is lost to the outside if there is no contamination. If the surface of the window is contaminated, the radiation raises the temperature of the contaminants. This increase in temper…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.