Matsushita Electric Industrial Co., Ltd.

Takashi Itoh

Masahide Yamauchi

Koji Fujii

Keisuke Koga

Toru Kawase

Masahiko Sukeno

Kazunori Ohta

The CRT device comprises a cold cathode electron gun that includes cathodes, a peripheral focusing electrode, and an accelerating electrode. The cathode has a structure in which an emitter electrode and a gate electrode are joined together with an insulating layer interposed therebetween. The electric potential difference from the emitter electrode is 60V for the gate electrode, 0V for the peripheral focusing electrode, and 4.6 kV for the accelerating electrode.

High resolution CRT device comprising a cold cathode electron gun

In a picture tube device with a field-emission cold cathode, including a plurality of electron-emitting cathodes, and a lead electrode provided with a plurality of apertures surrounding the plurality of electron-emitting cathodes respectively, a surface of the lead electrode has a curved shape that is convex in an electron emission direction. This makes it possible to obtain a high-resolution and high-performance picture tube device that has an excellent focus performance over an entire beam current.

Picture tube device having lead electrode with a curved shape

A cathode ray tube according to the present invention include a cold cathode electron gun, the cold cathode electron gun including a cold cathode array for emitting electrons through field emission, a gate electrode for controlling the field emission, a first selective electrode provided around the cold cathode array and the gate electrode, and a second selective electrode opposing the first selective electrode, and the second selective electrode is adapted to have a lower potential than the gate electrode and the first selective electrode. In accordance with this configuration, the divergence of electron beams emitted from any positions in the cold cathode array can be converged uniformly upon removing electron beams emitted at a great emission angle. This allows the electron beams thereafter to be made narrower by an electrostatic lens. As a result, the present invention can provide a cathode ray tube capable of forming a high-resolution image.

Electron lens and structure for a cold cathode of a cathode ray tube

A field emission electron source includes: a field emission array portion composed of an insulation layer with a plurality of apertures, which is formed on a substrate, an extraction electrode formed on the insulation layer, and a plurality of cathodes formed respectively on the substrate in the plurality of apertures; a cathode base for fixing the field emission array portion; and an electron lens portion composed of a plurality of electrode members having a function of accelerating and converging an electron beam emitted from the field emission array portion. An emission axis of the electron beam emitted from the field emission array portion has a predetermined angle with respect to an optical axis of the electron lens portion. Thus, the field emission array portion can be protected from impact caused by ions generated in the electron lens portion, thereby improving the life of a field emission electron source.

Field emission electron source, electron gun and cathode ray tube device using the same

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.

Electron gun and cathode-ray tube

A CRT device with an electron gun provided therein includes control means for controlling voltages applied to a cathode and a control electrode constituting the electron gun. The control means exerts control on each electrode voltage so that the difference between the cutoff voltage of the cathode and the voltage of the control electrode is greater when the luminance level of a luminance signal separated from picture signal is higher, thereby minimizing a spot diameter.

Growing community of inventors

Amagasaki, Japan

Takashi Itoh