Patent ID: 7187113

Claim:
A cathode ray tube comprising: a panel on inner surface of which a phosphor screen is formed; a funnel joined to the panel; an electron gun generating electron beams; a shadow mask mounted to the panel, the shadow mask having a faceplate portion and a peripheral skirt portion bent back from said faceplate portion, said faceplate portion further comprising an apertured portion and a non-apertured portion surrounding said apertured portion; and a frame having a supporting portion joined to said skirt portion and a bottom portion bent inward from said supporting portion and extending by width Da from the short side of said supporting portion, wherein Da satisfies: Da<Ha×La/P+Na where La represents distance between center point Fx of said faceplate portion and a short side of said apertured portion; Na represents distance between the short side of said apertured portion and a short side of border of said faceplate portion from which said skirt portion is bent; P represents distance between the electron beams deflection center Dx and the center point Fx of said faceplate portion; Ha represents distance between the short side of the border of said faceplate portion and a short side of rear end line of said supporting portion from which said bottom portion is bent.