Patent ID: 6304026
Filing Date: 2001-10-16
Classification: H01J

Abstract:
A color cathode ray tube comprising:a phosphor screen;an in-line type electron gun comprising an electron beam generating section having a cathode, a beam control electrode and an accelerating electrode for projecting three electron beams arranged approximately in parallel with each other in a horizontal plane toward said phosphor screen, a focus electrode, and an anode adjacent to said focus electrode and forming a main lens in cooperation with said focus electrode for focusing said three electron beams on said phosphor screen; anda deflection yoke for deflecting said three electron beams horizontally and vertically,said focus electrode including at least a first focus sub-electrode and a second focus sub-electrode on the order named from said cathode, said first focus sub-electrode and said second focus sub-electrode forming an electrostatic quadrupole lens therebetween, andan axial distance Lgf (mm) measured from an end of said first focus sub-electrode on a cathode side thereof to an end of said second focus sub-electrode on an anode side thereof, an axial distance Ls (mm) measured from said end of said second focus sub-electrode to said phosphor screen, and a useful diagonal dimension D (mm) of said phosphor screen satisfying a following relationship:0.06.times.Ls (mm).ltoreq.Lgf.ltoreq.26 (mm), and1.50.ltoreq.D/Ls.ltoreq.1.70.