The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 09, 2003
Filed:
Jun. 04, 2002
Masahide Yamauchi, Kyoto, JP;
Takashi Itoh, Amagasaki, JP;
Koji Fujii, Kashihari, JP;
Keisuke Koga, Kyoto, JP;
Toru Kawase, Katano, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A cathode includes emitter tips provided on a substrate, a gate electrode with an electric field formed between the gate electrode and the emitter tips, and terminals and leads for supplying voltages to the emitter tips and the gate electrode, respectively. A shield electrode further is provided between the cathode and a control electrode, and the shield electrode has a cylindrical projecting portion projecting toward the cathode, through which electron beams pass. The disturbance of an electric field by the leads influences the electron beams; however, this can be prevented by the projecting portion. Because of this, even if the size of the cathode is reduced, the distortion of an electron beam spot on a phosphor screen can be reduced. As a result, a cathode-ray tube with high resolution can be provided at a low cost.