Image tube power supply
AssigneeInternational Telephone and Telegraph Corporation
InventorAlan W. Hoover
Life of this patent
Estimating the term…
Abstract
This power supply detects the total power input to an image tube of the type utilizing microchannel plate electron multipliers in order to set the image output brightness. A current sensing resistor in the oscillator circuit provides a feedback potential in proportion to the total power demand of the image tube. This potential is applied to a transistorized circuit for limiting the input to the oscillator to a predetermined level.
Claims4
A controlled device brightness power supply for image tubes of the type containing a micro-channel plate electron multiplier and a phosphor screen comprising:
- oscillator means for providing A.C. power when coupled with a source of D.C. power;
- rectifier means coupled with said oscillator for providing D.C. power to the tube;
- power sensing means consisting of a resistive element electrically coupled in series between said D.C. power source and said oscillator for detecting changes in tube operating power corresponding to changes in the tube input illumination and reducing the microchannel plate electron multiplier voltage to provide a constant illumination at the phosphor screen;
- and
- control circuit means electrically coupled with the power sensor and oscillator in feed-back relation for controlling the A.C. power in repsonse to the changes in the tube operating power consisting of at least one transistor electrically coupled between the oscillator and the D.C. power source to control the conduction through the oscillator.
A controlled brightness power supply for image tubes of the type having a micro-channel plate electron multiplier comprising;
- oscillator means for providing A.C. power when coupled with a source of D.C. power;
- rectifier means coupled with said oscillator for providing D.C. power to the tube;
- bright source protection circuit means electrically coupled with the micro-channel plate and rectifier for preventing increases in tube illumination from damaging the tube cathode;
- and
- At least one resistor serially coupled with at least one output of said microchannel plate for detecting changes in the tube input illumination and limiting the D.C. power to the oscillator when current through the resistor exceeds a predetermined value.
Dependencies are inferred from the claim text.