Infrared thermometer with automatic calibration
US4784149A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1986 |
| Grant date | Nov 15, 1988 |
| Priority date | — |
| Expiry date | Jan 13, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/80
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Infrared radiation emitted from tissue surface of body cavity is measured by an infrared sensor located within a probe which generates a signal voltage dependent on the difference in temperature between the tissue and the infrared sensor. An additional ambient sensor measures the ambient temperature of the infrared sensor. The signals of the two sensors are added. To calibrate and eliminate errors, the housing of the device is provided with a chamber shaped to receive the probe and containing a target viewed by the infrared sensor. An error signal is thus generated which is added to the signals of the two sensors when they view the body tissue. A disposable, sanitary cover for the probe is made of a truncated polyethylene member of substantially uniform thickness closed by an end window. A filter in the probe suppresses absorption bands of polyethylene to eliminate errors due to minor variations in cover thickness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.