| 摘要 |
PURPOSE:To make is possible to sufficiently treat the surfaces of electrodes, constructing an electron gun, provided facing to each other by applying high voltage to them while applying a magnetic field produced by a current allowed to flow through a magnet or a coil turning relatively to the outer periphery of an electrode gun neck to a portion between the electrodes provided facing to each other. CONSTITUTION:All of a heater 2, a negative electrode 3, the first grid 4, the second grid 5, the third grid 6, the fourth grid 7, and the fifth grid 8 are connected to an earth via stem pins 18 in a stem 17, and pulse-shaped high voltage of 30-80kV is applied from a positive electrode terminal 5 to the sixth grid 9 via s convergence electrode 10, a valve spacer 11, an internal conducting film 14 deposited on the internal surface from the neck 12 to a funnel 13. Particularly, fine unevenness on the surfaces facing to each other of the fifth grid 8 and the sixth grid 9 forming a main lens and suspended particles are removed. And, a pair of AC electromagnets 21 are provided on the outside part of the neck 12 corresponding to between the sixth grid 9 and the fifth grid 8 so as to hold the neck 12 between themselves, and high voltage is applied to the sixth grid 9 while trning this magnet 21 relatively to the outer periphery of the neck 12. |
