ELECTRON GUN

PURPOSE:To obtain a power-saving and energy-saving type electron gun with excellent focusing performance wherein an aperture of an electron beam pass hole of a dish-shaped electrode is made to be smaller in its outlet than in its inlet to enable the electron gun to sharply enlarge the aperture of an electron lens inspite of a reduced neck diameter. CONSTITUTION:Three electron beam pass holes 33a, 33b and 33c are punched in a plate-shaped electrode 31 with a very small mutual clearance whereby respective holes are independent through bridge parts 34. A dish-shaped electrode 32 has three electron pass holes 35a, 35b and 35c punched same as siad plate-shaped electrode whereby the projected part 36 called burring is sharply different from an existing electrode in its shape. That is to say that the aperture of the electron beam pass hole is about the same as said plate-shaped electrode in its inlet 37, but smaller in its outlet 38 than in the inlet 37. With said construction the electron lesn aperture can sharply be enlarged while keeping an outer diameter of the electron gun same as in the past.