Kabushiki Kaisha Toshiba

Kazunori Satou

Hirofumi Ueno

Tsutomu Takekawa

Tomonari Ishihara

Shigeru Sugawara

Osamu Ono

Takashi Awano

Junichi Kimiya

Kiyoshi Tokita

Takahiro Hasegawa

Toshinao Sone

Kazunori Nakane

Noriyuki Miyamoto

Hiroshi Urata

Shigeo Fukuda

Masatane Jida

At least one of the electrodes of an electron gun assembly is constructed by coupling at least first and second electrode members arranged in a direction of passing of electron beams. The first electrode member has a projecting portion on an end face thereof, which is to be coupled to the second electrode member disposed adjacent to the first electrode member. The first electrode member is coupled to the second electrode member via the projecting portion.

Cathode-ray tube apparatus

The electron beam generating section in an electron gun assembly includes a cathode having an electron emitting surface. The surface of the cathode is divided into at least three regions of first, second and third regions which have different electron emission capabilities. The first region is arranged in the center of the surface of the cathode. The second region has its portions arranged on opposite sides of the first region in the horizontal direction. The third region has its portions arranged on opposite sides of the first region in the vertical direction.

Electron gun assembly and cathode ray tube apparatus

An electron gun structure applied to a color cathode-ray tube comprises a focus electrode, an ultimate acceleration electrode and at least one intermediate electrode disposed between the focus electrode and the ultimate acceleration electrode, the focus electrode, the ultimate acceleration electrode and the at least one intermediate electrode forming a main lens. The electron gun structure also comprises a voltage application unit for applying to the focus electrode a dynamic voltage increasing in accordance with an increase in a degree of deflection of the electron beams, and applying to the intermediate electrode a voltage obtained by dividing a voltage applied to the ultimate acceleration electrode by means of a voltage dividing resistor. The electron gun structure further comprises at least one cylindrical additional electrode electrically insulatively covering a part of the electrode constituting the electron lens, the at least one cylindrical additional electrode being electrically connected to the intermediate electrode.

Color cathode-ray tube apparatus with multi-lens electron focusing and yoke deflection

A main lens includes a second segment, a sixth grid and an additional electrode disposed between the second segment and the sixth grid. A first-level constant voltage and a second-level constant voltage are applied to the second segment and sixth grid, respectively. A third-level voltage, which is at a level between the first level and the second level, is applied to the additional electrode. In accordance with the increase in a deflection amount of an electric beam, the third-level voltage varies as a value expressed by ((voltage to the additional electrode)&minus;(voltage to the second segment))/((voltage to the sixth grid)&minus;(voltage to the second segment)). An auxiliary lens having lenses including a third grid and a first segment has a focusing power decreasing in accordance with an increase in the deflection amount of the electron beam.

An electron gun assembly has at least one additional electrode located along the equipotential plane of a potential distribution formed between a focusing electrode and anode electrode forming a main lens. In a no-deflection state, the additional electrode receives a voltage of a predetermined level corresponding to the potential of the equipotential plane on which the additional electrode is located. In a deflection state, letting Vf be the application voltage of the focusing electrode, Eb be the application voltage of the anode electrode, and Vs be the application voltage of the addition electrode, a value (Vs&minus;Vf)/(Eb&minus;Vf) changes with an increase in electron beam deflection amount, while the additional electrode forms an electron lens having different focusing powers in the horizontal direction and vertical direction.

Color cathode ray tube apparatus

A color cathode-ray tube apparatus comprises an electron gun structure for generating three electron beams arranged in line, the three electron beams comprising a center beam and a pair of side beams. The electron gun structure forms a main lens for ultimately focusing the three electron beams on a phosphor screen. The main lens is formed by a focus electrode, an additional electrode and an anode electrode which are arranged in a direction of traveling of electron beams. A voltage application unit applies a voltage to each of the electrodes such that a voltage higher than a voltage applied to the focus electrode and lower than a voltage applied to the anode electrode is applied to the additional electrode, and in synchronism with deflection of the three electron beams by the deflection yoke, a value S varies: S&equals;&lsqb;(applied voltage to the additional electrode)&minus;(applied voltage to the focus electrode)&rsqb;/&lsqb;(applied voltage to the anode electrode)&minus;(applied voltage to the focus electrode)&rsqb;. An angle of emission of each of the side beams emanating from the main lens varies in synchronism with a variation of the value S.

Color cathode-ray tube apparatus

An electron gun assembly includes a plurality of cathodes arranged in an in-line direction, at least first through fourth grids having electron beam passing holes arranged in an in-line direction, and an insulation support for sandwiching the cathodes and the grids between and fixing the cathodes and the grids from a direction perpendicular to the in-line direction. The second grid and the fourth grid are supplied with substantially the same low potential, the third grid is supplied with a potential higher than the potential of the fourth grid, and the second grid is fixed to the insulation support on a side of the third grid. The third grid has a cup-shaped electrode on a side of the second grid, the cup-shaped electrode including a plane portion having electron beam passing holes, an opening portion, and planting portions planted in the insulation support.

Electron gun structure

An inline type electron gun assembly has a main lens for focusing three electron beams on a phosphor screen. A resistor is arranged in a cathode ray tube. A voltage obtained by dividing a high voltage with the resistor is applied to an intermediate electrode. Voltages of a focusing electrode, the intermediate electrode, and a final accelerating electrode that constitute the main lens are determined to increase sequentially. Electron beam holes in the intermediate electrode on the focusing electrode side, and electron beam holes in the intermediate electrode on the final focusing electrode side form vertically elongated holes longer in the vertical direction than in the horizontal direction. Electron beam holes in the focusing electrode on the intermediate electrode side and electron beam holes in the final accelerating electrode on the intermediate electrode side form open holes having no side wall portions. A color cathode ray tube having an electron gun assembly capable of improving resolving power can be provided.

Color cathode ray tube

In a color cathode ray tube apparatus having an electron gun assembly for emitting three electron beams disposed in one line, the electron gun assembly has at least first, second, and third electrodes G5, G7, and G9 applied with a voltage which changes in synchronization with deflection of electron beams. The first electrode and an electrode G4 adjacent thereto form first eccentric lenses for deflecting a pair of side beams in a direction in which the side beams extend to be close to the center beam. The second electrode and an electrode G6 adjacent thereto form second eccentric lenses for deflecting the side beams in a direction in which the side beams extend to be apart from the center beam. The third electrode and an electrode G8 adjacent thereto form third eccentric lenses for deflecting the side beams in a direction in which the side beams extend to be close to the center beam. An electron lens common to the three electron beams is formed between the second and third eccentric lenses. It is possible to realize a color cathode ray tube apparatus which displays a high quality image over the entire area of the screen by means of these electron lenses.

Electron gun for color cathode ray tube

A color cathode-ray tube apparatus comprising a video signal generator, a delay circuit, an electron gun assembly, a deflection yoke, a shadow mask, and a phosphor screen. The signal generator generates three video signals simultaneously. The delay circuit delays the first and second video signals with respect to the third video signal. The screen has phosphor elements regularly arranged. The electron gun assembly generates three electron beams at different times, in response to the three signals output by the delay means. These beams are applied to the phosphor screen, and the phosphor elements of the screen emit red light, green light and blue light. Any three electron beams the gun assembly emits simultaneously form three beam spots on the screen. These spots overlap for a distance longer than half the horizontal diameter of a beam spot formed by an electron beam of the greatest current which the gun assembly can generate. The shadow mask, located between the phosphor screen and the gun assembly, controls the beams, making them land at desired positions on the phosphor screen. The deflection yoke deflects the beams in the horizontal and vertical directions, such that the electron beams scan the entire screen. The beams, deflected in the horizontal direction, land at substantially the same point on the screen, forming a color pixel thereon.

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Fukaya, Japan

Kazunori Satou