CATHODE RAY TUBE DEVICE INCLUDING YOKE PORTION HAVING OUTER SURFACE WITH CROSS SECTION SHAPED AS BARREL

摘要

PURPOSE: A cathode ray tube device is provided to achieve improved anti-atmospheric pressure strength of a vacuum vessel and improved luminance by effectively reducing deflection power. CONSTITUTION: A cathode ray tube device comprises a vacuum vessel including a panel portion and a yoke portion; and a deflection yoke arranged on the outer surface of the vacuum vessel. At least one of cross sections of the yoke portion, vertical to a tube axis from a neck connection position to a screen end of the deflection yoke has a non circular shape having the maximum outer radius between vertical and horizontal directions of a screen. When a reference deflection position is located at a point on the tube axis where the angle formed between a line and the tube axis becomes 1/2 of the cathode ray tube deflection angle, wherein the line connects the diagonal end of the screen of aspect ratio M:N(vertical axis direction length to horizonal axis direction length ratio of screen) and a point on an electron gun side of the screen, a formula (M+N)/(2(M¬2+N¬2)¬1/2)(SA+LA)/2DA =0.86 is established, wherein SA is an outer diameter of vertical axis direction yoke portion, LA is an outer diameter of horizontal axis direction yoke portion, and Da is an outer diameter of maximum yoke portion at the reference deflection position. The yoke portion has an outer surface with a cross section shaped as a barrel around the reference deflection position at a cross section vertical to the tube axis.