Optoelectronic device for videofrequency scanning of images
US4423437A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 14, 1981 |
| Grant date | Dec 27, 1983 |
| Priority date | — |
| Expiry date | Oct 14, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/06
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The optoelectronic device comprises an optical element for producing an image scan and an optical element for focusing on an array of detectors. The detected signals are processed by amplifying circuits and a thermal-drift correcting unit comprising an occultation device having two states. A correction loop of the unit includes a memory for storing the values of amplifying circuit signals in the first state of the occultation device, a first circuit for subtracting the stored values from the amplifying circuit outputs in order to compensate for thermal drift, a measuring circuit for obtaining the mean value of the amplified videofrequency signals, and a second circuit for subtracting the mean value from the signal of each detector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.