Device for receiver for optical signals
US3999060A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 11, 1975 |
| Grant date | Dec 21, 1976 |
| Priority date | — |
| Expiry date | Feb 11, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S136/291
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A device is provided for controlling the sensitivity of a receiver of the type comprising a photosensitive element operative to convert radiant energy into electric signals and having an amplifier connected to the output of the photosensitive element and signal processing members for separating a useful signal from interfering background radiation. A sensor device is connected to the photosensitive element to sense the direct current which the element emits in response to radiation from the sun or other strong sources of disturbance, the sensor device being operative to emit a signal when the direct current exceeds a predetermined value, and a switching device responsive to said signal operates to switch the amplifier from a given fixed sensitivity level to a lower fixed level of sensitivity. The arrangement may comprise an amplifier having a feedback circuit, with the switching device taking the form of a diode which is selectively driven into conduction by said signal and which operates in its conducting state to connect a shunt resistor across the amplifier feedback circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.