Method and apparatus for calibration of comfort control IR sensor
US5531377A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1995 |
| Grant date | Jul 2, 1996 |
| Priority date | — |
| Expiry date | Feb 1, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K2201/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An infrared sensor for determining the temperature of a car interior includes a thermistor and a thermopile in a can and a protective window which exposes the thermopile to the thermal energy of the car interior. The combined outputs of these thermally sensitive elements represents the interior radiant temperature. The effectiveness of the thermopile changes if the window gets dirty to change its output. A resistive heater on the can is used to heat the sensor during calibration. A microprocessor receiving the outputs of the sensor has an algorithm for adjusting a gain which compensates for sensor changes. When the interior temperature is stable, the sensor is heated and thermistor values before and after heating the sensor are used as a basis for adjustment of the gain.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.