Low light level image pick-up tube arrangement
US3974331A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 6, 1974 |
| Grant date | Aug 10, 1976 |
| Priority date | — |
| Expiry date | May 6, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/75
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A low light level image pick-up tube is protected from excessive illumination intensity damage by controlling a very high voltage assembly supplying the tube. The tube comprises in a preferred embodiment a plurality of image intensifier stages in cascade preceding an electron gun from which a video signal is provided by electronic scanning. A mean level video regulation circuit provides from the video signal an output signal used for controlling the supply voltage value to at least one of the image intensifier stages including the last one i.e. that preceding the electron gun. Further, a signal proportional to the supply current to the last image intensifier stage is used for controlling the supply voltage value of the input image intensifier stage which receives focussed radiation from an observed field.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.