| 摘要 |
PURPOSE:To eliminate a change of the resolution due to the angle of incidence of an electron beam and prevent the occurrence of the resolution irregularity by inclining a phosphor screen against the center axis of the beam and making the curve shape facing the beam on the cross section of the phosphor sereen a logarithmic spiral curve with the deflection center serving as the origin. CONSTITUTION:A phosphor screen 7 is inclined against the center axis 9 of a beam, and the curve shape facing the beam on the cross section of the phosphor screen 7 is made a logarithmic spiral curve (l) with the deflection center A serving as the origin. Thereby, the angle of incidence of the electron beam to all points on the phosphor screen from the deflection center is made completely constant, the resolution can be made completely equal over the whole area of the phosphor screen, thus an excellent image with no resolution irregularity can be obtained. |
