Matsushita Electric Industrial Co., Ltd.

Matsushita Electronics Corporation

Yoshikazu Iwai

Masahide Yamauchi

Satoru Nakagawa

Naomi Nishiki

Shinji Sasaki

Yuji Uesugi

Yoshiki Hayashida

Masaki Kawasaki

Kiyohito Miwa

Ayumu Takakuwa

Tosinobu Yokoyama

Kiyotaka Ihara

Yasuyuki Shibuta

A method of manufacturing a shadow mask assembly, in which a shadow mask is fastened to a support frame in a tensioned state, includes applying a preliminary tension force with a magnitude of 9.8 to 490 N to the four corners of the shadow mask outwardly aslant with respect to sides of the shadow mask. A main tension force is then applied to each of at least a pair of mutually opposite sides of the shadow mask outwardly perpendicularly to the sides. Thereafter, the shadow mask to which the main tension forces have been applied is fastened to the frame side of the support frame.

Shadow mask assembly manufacturing method and cathode ray tube manufacturing method

A cathode structure comprises a cylindrical metal sleeve having aperture portions at both ends, a base metal having an aperture portion on one end, which is fitted onto one of the aperture portions of the metal sleeve, and an electron-emitting layer, which is formed on a flat portion of an outside surface of the base metal. After an electron-emitting material is sprayed onto the base metal, its surface is mechanically flattened to form the electron-emitting layer. Thus, the planarity of the surface of the electron-emitting layer can be improved without deterioration of the electron emission characteristics and the moir&eacute; can be decreased without reduction of the resolution.

Cathode, method for manufacturing the cathode, and picture tube

A method for producing an oxide cathode including a sleeve containing a heater coil, a cathode substrate provided on one end of the sleeve, and an emissive material layer formed by thermally decomposing an alkaline earth metal carbonate layer adhered onto the cathode substrate, which method includes adhering the alkaline earth metal carbonate onto the cathode substrate so that it has a bulk density of 0.5 to 0.8 g/cm , then pressing it so that the bulk density becomes not more than 0.9 g/cm , and then thermally decomposing it in vacuum. Accordingly, an oxide cathode in which the current density distribution of emission electrons is smooth and an electron emission characteristic is not deteriorated when operated for a long time is realized, and a method for producing a cathode-ray tube with high resolution in which moire is invisible is provided.

Method for producing oxide cathode

An electron gun is provided, in which a capacitance between a cathode and other electrodes, especially a control electrode is reduced largely without substantially changing a structure for supporting the cathode with an insulator. The cathode of this electron gun is disposed inside of the cylindrical metal shell. The cathode and the cylindrical metal shell are connected by three metal tabs. The cylindrical metal shell fits into a hole formed in the center portion of the insulator, and a metal outer frame is attached to the periphery of the insulator. The metal outer frame is welded to the inner surface of a cathode metal support. There is a control electrode facing the electron emitting surface of the cathode at a predetermined distance. Plural electrodes including an accelerating electrode are disposed in turn beyond the control electrode. Peripheries of the cathode metal support, control electrode, an accelerating electrode and other electrodes are embedded into sides of a pair of supporting rods that extend axially, so that the electrodes are fixed with a predetermined space between the electrodes.

Electron gun with reduced capacitance between electrodes and cathode-ray

Growing community of inventors

Osaka, Japan

Yoshikazu Iwai