Electron gun assembling apparatus and method of assembling electron gun
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsYasuki Kimura, Takashi Shirase, Masamitsu Okamura, Shuichi Maezono
Life of this patent
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Abstract
An electron gun assembling apparatus has a cathode driving mechanism (12,13) for moving a cathode (1), a laser displacement gage (14) to measure a height of a surface of the cathode (1) in a non-contact manner at a cathode surface measuring position outside an electron gun assembly (24), an electric micrometer (11) to measure a height of an upper surface of a first electrode (3) in the electron gun assembly (24), and an electric micrometer (8) to measure a height of a lower surface of a second electrode (4) in the electron gun assembly (24).
Claims19
A method of assembling an electron gun, for positioning and fixing a cathode to an electron gun assembly in which at least first and second electrodes are supported by an insulating glass and are arranged at a predetermined interval, said method comprising the steps of:
- measuring a position of a surface of said cathode at a cathode surface measuring position outside said electron gun assembly;
- measuring a position of an upper surface of said first electrode in said electron gun assembly;
- measuring a position of said second electrode in the electron gun assembly;
- determining an interval between said first electrode and said second electrode in said electron gun assembly on the basis of at least the measured positions of the upper surface of said first electrode and said second electrode, and a measured and known thickness of said first electrode;
- calculating an optimal value of an interval between said first electrode and said cathode, which depends on the interval between said first electrode and said second electrode;
- moving said cathode from the cathode surface measuring position to a cathode assembling position where said cathode is incorporated into said electron gun assembly;
- determining a current position of the surface of said cathode from the position of the surface of said cathode at the cathode surface measuring position and a variation in position of the surface of said cathode which is caused by a movement of said cathode to the cathode assembling position;
- and
- positioning and fixing said cathode by inserting said cathode into said electron gun assembly until a difference between the current position of the cathode surface and the position of the first electrode upper surface reaches the optimal value calculated.
An electron gun assembling apparatus comprising:
- an electron gun assembly holding means for holding an electron gun assembly including at least first and second electrodes which are supported by an insulating glass and are arranged vertically at a predetermined interval;
- a cathode holding means for holding a cathode to be incorporated into said electron gun assembly;
- a cathode driving means for moving said cathode holding means to transport said cathode until said cathode is mounted in said electron gun assembly;
- a cathode surface measuring means for measuring a position of a surface of said cathode which is held by said cathode holding means and is located outside said electron gun assembly;
- a first electrode upper surface measuring means for measuring a position of an upper surface of said first electrode in said electron gun assembly held by said electron gun assembly holding means;
- a second electrode measuring means for measuring a position of said second electrode in said electron gun assembly held by said electron gun assembly holding means;
- a cathode position measuring means for measuring a variation in position of the surface of said cathode held by said cathode holding means carried by said cathode driving means;
- an arithmetic means for determining an interval between said first electrode and said second electrode in said electron gun assembly on the basis of at least position information obtained by said first electrode upper surface measuring means and said second electrode measuring means, and a measured and known thickness of said first electrode, and for calculating an optimal value of an interval between said first electrode and said cathode, which depends on the interval between said first electrode and said second electrode;
- and
- a control means for determining a current position of the surface of said cathode from the position of the surface of said cathode measured by said cathode surface measuring means and a variation in position of the surface of said cathode obtained by said cathode position measuring means, and for controlling said cathode driving means to insert said cathode into said electron gun assembly until a difference between the current position of the cathode surface and the position of the first electrode upper surface reaches the optimal value calculated by said arithmetic means.
Dependencies are inferred from the claim text.