Patent · US Expired

Dynamic focus amplifier output with step-up autotransformer

US6690124B2 · kind B2 · utility

3Cited by
10References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 5, 2001
Grant dateFeb 10, 2004
Priority date
Expiry dateDec 31, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N3/26
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An autotransformer steps up the output of a high voltage amplifier for applying a drive signal to the focus electrode of a CRT. A parabolic signal is obtained or generated at a deflection frequency such as the horizontal scanning frequency and is applied as an input to the amplifier. The amplifier output is coupled to a center tap of the autotransformer. One winding is serially coupled to the focus electrode and the other winding is AC coupled by a capacitor to ground, in parallel with the amplifier output. The transformer steps up the amplifier output voltage and can reduce the voltage rating required of transistors in the amplifier.

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