Patent ID: 6020939
Filing Date: 2000-02-01
Classification: H01J,H04N

Abstract:
A method for reducing emission of electromagnetic interference generated in displaying video on a cathode ray tube coupled to at least a video data signal and a horizontal synchronization signal, said video data signal and said horizontal synchronization signal being derivable from a pixel clock signal, the method comprising the following steps:time-shifting said video data signal so as to produce therein at least a first phase and a second phase at a phase rate of change (f.sub.r-o-c) producing a sufficiently large frequency spread (.DELTA.f) in a Fourier transform of said pixel clock signal as to move at least some spectral components of said pixel clock signal outside an EMI measurement window having bandwidth f.sub.m ;wherein measurable spectral components of said Fourier transform remaining within said bandwidth f.sub.m are reduced.