Thermal imager referencing system
US5864135A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 11, 1996 |
| Grant date | Jan 26, 1999 |
| Priority date | — |
| Expiry date | Dec 11, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/23
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thermal imager referencing system comprises two rotating cranks in the form of discs (7, 8) each pivotally attached to connecting member (9). The discs (7, 8) are rotated at a constant speed causing two mirrors laterally displaced along connecting member (9) to intercept an optical path X of a thermal imager associated with the referencing system. Each rotation through 360 degrees of the discs (7, 8) causes each mirror to pass once through the optical path, the mirror surfaces being respectively arranged to cause a linear array of detector elements (not shown) of the thermal imager to view alternately thermo-electric devices (14, 16), which are at different temperatures, during the flyback time associated with the thermal imager. The referencing system enables processing means of the thermal imager to normalize the detector array, compensating for DC offset and differences in gain between different elements of the detector array. The referencing system is of a particularly compact design and minimizes the effect of any temperature variations across the surfaces of the Peltier on the normalization process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.