Thermal image detector with fast shutter period, and method of operation
US5432348A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 28, 1993 |
| Grant date | Jul 11, 1995 |
| Priority date | — |
| Expiry date | Dec 28, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/60
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The disclosure relates to thermal image detectors and, more particularly, to linear or matrix type pyroelectic detectors. These detectors work differentially, in successive phases of masking and illumination, by use of a shutter that is synchronized with the signal processing circuits. The detected signals are shed in the form of charge packets into a shift register (RD). To reduce the noises that are proportional to the duration of the illumination or masking phases, the shutter is made to work at higher speed and several successive illumination/masking cycles are carried out by making the shift register go backward between two cycles. The shift register is emptied to give an image signal only after two or more cycles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.