Patent ID: 6671006
Filing Date: 2003-12-30
Classification: H04N

Abstract:
In a cathode ray tube display arrangement in which displays are realized by line-by-line scanning of a display screen of a cathode ray tube by an electron beam spot, the cathode ray tube display arrangement comprising a deflection circuit for generating a repetitive deflection current to deflect the electron beam spot in a first direction, wherein the deflection current has a shape for obtaining an approximate linear scan on the display screen in the first direction during a scan period, a method for generating a spot position indication signal for indicating a position of said spot on the display screen, characterized in that the method comprises the steps:generating, in a certain scan period, a position information related to the deflection current; measuring a first instant as an instant at which the position information has a first value; measuring a second instant as an instant at which the position information has a second value; and calculating, in a later scan period, the spot position indication signals a linear function in time whereby, in a steady state situation, the spot position indication signal has predetermined position indication values at instants in this later scan period corresponding to the first and the second instants, respectively, and the spot position indication signals independent of a width of the scan or the number of scanning lines.