Non-contact temperature measurement of a static or moving target
US4693615A · kind A · utility
Inventor
Key dates
| Filing date | Jun 13, 1985 |
| Grant date | Sep 15, 1987 |
| Priority date | — |
| Expiry date | Jun 13, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/0805
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining the temperature of a hot body by a non-contact technique. It comprises a chopping disc 2 which may be disposed in the path of the radient heat energy from the object so providing a pulsed output of radient heat energy directed towards a pyroelectric element 7. Between the pyroelectric element 7 and the disc 2 is a further rotatable disc 4 having a pair of wavelength filters 6 and 6'. A microprocessor 14 operates to rotate the disc 4 to interpose each filter 6 and 6' in turn in the path of the pulsed output from the disc 2 at predetermined time intervals. The consequent output from the pyroelectric element 7 is, after amplification, rectification and smoothing in suitable circuits, fed to the microprocessor 14, which then calculates the ratio of the signal from the element 7 representative of power output through one of the filters, and the signal from element 7 representative of power output through the other filter. In this way the temperature of the hot body is determinable without prior knowledge of the emissivity characteristics of the hot body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.