Patent ID: 7250714

Claim:
A cathode ray tube comprising: a panel including an inner surface and an outer surface; a funnel having a rear and a front and connected to the panel at the front; a neck connected to the rear of the funnel; and a shadow mask mounted within the panel; wherein the inner surface of the panel satisfies the following condition: 0.2≦Px≦0.4, 0.3≦Py≦0.6 where when the inner surface of the panel is expressed by the following biquadratic z ⁢ ⁢ ( x , y ) = ∑ i , j = 0 , 2 , 4 ⁢ ⁢ A i , j ⁢ x ⁢ i ⁢ y ⁢ j where A i,j are constants, based on the inner central point of the panel with the three-dimensional orthogonal coordinates system defined by the x, y and z axes, Px and Py are defined by the following formula: Px = A 20 A 20 + A 40 , ⁢ Py = A 02 A 02 + A 04 .