Patent · US Expired

Device for driving directly heated cathode of cathode ray tube

US5744911A · kind A · utility

4Cited by
1References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1995
Grant dateApr 28, 1998
Priority date
Expiry dateDec 21, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J1/135
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A device for driving a directly heated cathode of a cathode ray tube eliminating a delay due to inductance of a transformer. A transformer that produces the heater-heating signal voltage applied to the cathode includes a secondary coil divided into first and second coils. The voltage induced in the first coil is used for the heater-heating voltage and the signal induced in the second coil is synchronized with the voltage induced in the first coil and used as a bias voltage for turning on and off a switching element in synchronization with the heater-heating voltage. The switching element turns on only when the heater-heating signal voltage is applied to a control terminal of the switching element.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.