Hitachi, Ltd.

Hitachi Device Engineering Co., Ltd.

Other

Hitachi Electronic Devices Co., Ltd.

Hitachi Electronics Devices Co., Ltd.

Shoji Shirai

Go Uchida

Kenichi Watanabe

Shinichi Kato

Masaaki Yamauchi

Tomoki Nakamura

Masayoshi Furuyama

Masakazu Fukushima

Kazunari Noguchi

Yasuharu Yatsu

Kazuhisa Oshita

Tutomu Tojyou

Nobuyuki Suzuki

Yasuo Tanaka

Shoichi Wakita

Hidemasa Komoro

Yoshiaki Takahashi

Kazuo Majima

Hiroshi Takano

Toshio Nakayama

Mamoru Tsuzurahara

Sakae Ishii

Takashi Kinami

Noboru Mizukami

Yoshiaki Iidaka

Shigeo Mikoshiba

Masayoshi Misono

Fumio Noda

Shinichi Shinada

Satoru Miyamoto

Masahiro Miyazaki

Yukihiro Izumida

Yuichi Inoue

Minoru Yabe

Kotaro Aoki

Kenichi Matsuda

Masafumi Nagaoka

Kouichi Saitou

Akio Yamaguchi

Tatsuo Nishimura

Koichi Miyagawa

Tetsuya Enomoto

In an electron gun including a cathode, a control electrode, an acceleration electrode Ga focusing electrode Gand an anode, longitudinally elongated concave SL-V which surround an electron beam aperture G-H and have a long axis in the vertical direction is formed at a focusing electrode Gside of the acceleration electrode Gand an electron beam aperture G-BH formed at the acceleration electrode Gside of the focusing electrode Gis formed in a longitudinally elongated shape having a long axis in the vertical direction. Due to such a constitution of the present invention, non-uniformity of the beam spot shape attributed to a deflection quantity can be reduced whereby the optimum focusing can be realized over the whole area of a screen.

Color cathode ray tube

The present invention aims at maintaining the high focusing performance with a low deflection power in a projection tube which is used as a projection type TV receiver or a projector and is operated at a high voltage and with a single-electron-beam high current. A neck outer diameter of a portion on which a deflection yoke is mounted is made smaller than a neck outer diameter of a portion which accommodates an electron gun. A final electrode of the electron gun has a diameter thereof gradually decreased toward a phosphor screen. The maximum anode voltage of the projection tube is set to equal to or more than 25 KV and the maximum beam current is set to equal to or more than 4 mA.

Projection tube having different neck diameters

A cathode ray tube has an anode and a focus electrode. The large-diameter cylinder portion of the focus electrode is disposed concentrically within a large-diameter cylinder portion of the anode. The anode and a first electrode facing a cathode side end of the focus electrode are electrically connected together within the cathode ray tube. The following relationship is satisfied: &minus;LP&plus;184.9&gE;LG &gE;0.0004 LP &minus;0.1571 LP &plus;21.006 LP&minus;922.41, where LG (mm) is an axial length of the focus electrode, and LP (mm) is a distance from a phosphor screen side end of the focus electrode to a center of a phosphor screen.

Cathode ray, tube including an electron gun having specific relation of axial length of focus electrode and focus electrode-screen distance

A color cathode ray tube having an electron gun including an electron beam generating portion arrayed in a horizontal direction for generating three electron beams, and a main lens for focusing the three electron beams from the electron beam generating portion upon a fluorescent face. A final stage of the main lens is formed between a focusing electrode and an accelerating electrode. The focusing electrode is divided into at least two focusing electrode parts. A quadrupole electron lens is formed for each of the electron beams between a first focusing electrode part and a second focusing electrode part, and the strength of the quadrupole electron lens for the central electron beam is different from the strength of the quadrupole electron lens for the side electron beams.

A cathode ray tube is provided having an electron gun equipped with a main lens having a function of controlling a shape of an electron beam spot which is deflected to the peripheral portion of a display screen, to improve a resolution at the peripheral portion of the screen of the cathode ray tube for use in a direct view color television receiver or a color display terminal. To reduce the dynamic correction voltage of the electron gun, an electrostatic quadrupole lens with a simple structure is used, thereby reducing deterioration due to the deflection aberration of the electron beam spot at the peripheral portion of the screen.

Cathode ray tube with low dynamic correction voltage

Color cathode ray tube having an improved electron gun

A lens structure of a pre-focus part of an Hi-UPF electron gun to be used for a cathode ray tube has a cathode, a control electrode, an acceleration electrode, a first anode, a focus electrode and a second anode arranged in this order. The first anode and the second anode are to be commonly supplied with an anode voltage, and the focus electrode is to be supplied with a focus electrode. In a cathode ray tube of this construction, in the pre-focus part, the control electrode has an electrode beam passage hole of 0.57 mm or smaller and the distance in the vicinity of the electron beam passage hole between the acceleration electrode and the first anode is 1.9 mm or smaller.

Cathode ray tube with UPF type electron gun having particular electrode structure and spacing

A cathode ray tube has an anode of a large-diameter cylinder portion on its phosphor screen side and a small-diameter cylinder portion on its cathode side connected together, and a focus electrode formed of a large-diameter cylinder portion of a diameter larger than that of the small-diameter cylinder portion of the anode and a small-diameter cylinder portion having a diameter smaller than that of the small-diameter cylinder portion of the anode, the large-diameter and small-diameter cylinder portions being connected together. The large-diameter cylinder portion of the focus electrode is disposed concentrically within the large-diameter cylinder portion of the anode. The anode and a first electrode facing a cathode side end of the focus electrode are electrically connected together within the cathode ray tube. The following relationship is satisfied: &minus;LP&plus;184.9&gE;LG &gE;0.0004 LP &minus;0.1571 LP &plus;21.006 LP&minus;922.41, LP&gE;131.7, where LG (mm) is an axial length of the focus electrode, and LP (mm) is a distance from a phosphor screen side end of the focus electrode to a center of the phosphor screen.

Cathode ray tube including an electron gun having specific relation between axial length of focus electrode and lens-screen distance

A color cathode ray tube includes third, fourth and fifth electrodes and an anode in its electron beam focusing section. A first-type electrostatic quadrupole lens is formed between first and second members of the fifth electrode for focusing electron beams in one of horizontally and vertically and diffusing the electron beams in the other of horizontally and vertically increasingly with decreasing beam deflection, and a second-type electrostatic quadrupole lens is formed between first and second members of the third electrode for focusing the electron beams in the other of horizontally and vertically and diffusing the electron beams in the one of horizontally and vertically increasingly with the decreasing beam deflection, and an electron lens is formed between the fourth electrode and a first aperture formed in a first surface of the second member of the third electrode adjacent to the fourth electrode, the first surface being on a side of the second member of the third electrode opposite from the fourth electrode, for diffusing the electron beams horizontally and focusing the electron beams vertically increasingly with the decreasing beam deflection.

Color cathode ray tube having electrostatic quadrupole lenses

A color cathode ray tube includes an evacuated envelope formed of a panel portion having a phosphor screen on an inner surface thereof and housing a shadow mask, a neck portion and a funnel portion connecting the panel portion and the neck portion, and an in-line electron gun housed in the neck portion. The in-line electron gun includes a main lens and an electrostatic quadrupole lens. The focus electrode of the electron gun has a single opening at one end thereof for passing the three electron beams and opposes an anode to form a main lens therebetween. The single opening has a diameter larger in a horizontal direction than a diameter thereof in a vertical direction. A distance from the main lens to the phosphor screen is not larger than 300 mm, a vertical mask aperture pitch on a vertical center line of the shadow mask is not larger than 0.28 mm at a center of the shadow mask, and an outer diameter T of the neck portion housing the in-line electron gun satisfies the following inequality 23.2 mm&lE;T&lE;25.9 mm, and a value D of twice a distance from a center of a trajectory of a side electron beam of the three electron beams to a horizontal edge of the single opening satisfies the following inequality 5.0 mm&lE;D&lE;6.5 mm.

Color cathode ray tube having a small neck diameter

A color cathode ray tube includes a three-color phosphor screen, a shadow mask spaced from the phosphor screen and a three-beam type electron gun. The main lens section includes a focus electrode and an anode facing the focus electrode, each of the focus electrode and the anode has an electrode having a single opening common for three electron beams in an end thereof facing each other and a plate electrode disposed therein. The focus electrode is formed of at least one first sub-electrode adapted to be supplied with a first focus voltage and at least one second sub-electrode adapted to be supplied with a second focus voltage, one of the at least one first sub-electrode and the at least one second sub-electrode faces the anode. The second focus voltage is a fixed voltage superposed with a dynamic voltage varying with beam deflection, and an electrostatic quadrupole lens is formed between a first one of the at least one first sub-electrode and a first one of the at least one second sub-electrode. An inequality V >H&minus;2&times;S is satisfied, where V and H are vertical and horizontal diameters of the single opening, respectively, S is P&times;L/Q, P is a horizontal center-to-center spacing between adjacent phosphor elements at a center of the phosphor screen, Q is an axial spacing between the phosphor screen and the shadow mask at the center of the phosphor screen, and L is an axial distance between the shadow mask and the single opening in the focus electrode.

A three in-line beam type color CRT includes a focus electrode and an anode. The focus electrode includes a first focus sub-electrode supplied with a first fixed focus voltage and a second focus sub-electrode supplied with a second fixed voltage superposed with a dynamic voltage synchronized with beam deflection, and the first and second focus sub-electrodes form a quadrupole lens therebetween. Two side electron beams are deflected toward a center electron beam with increasing dynamic voltage in the quadrupole lens. An axial distance Lgf (mm) from a cathode side end of the first focus sub-electrode to an anode side end of the second focus sub-electrode, an axial distance Ls (mm) from the end of the second focus sub-electrode to the phosphor screen, and a useful diagonal dimension D (mm) of the phosphor screen satisfy 0.06&times;Ls (mm)&lE;Lgf (mm)&lE;26 (mm) and 1.50&lE;D/Ls&lE;1.70.

Wide-angle deflection color cathode ray tube with a reduced dynamic focus voltage

A cathode-ray tube that has an electron gun including a final-stage main lens made up of a last accelerating electrode and a focusing electrode and having a focus action stronger in horizontal direction than in vertical direction, an electron lens of a first kind formed between the divided focus electrodes and having a focus action stronger in the vertical direction than the horizontal direction to vary the cross sectional shape of an electron beam with an increase of the deflection amount, an electron lens of a second kind formed between the divided focus electrodes for weakening the lens strength with an increase of the deflection amount of an electron beam, and an electron lens of a third kind made up of at least one electrode constituting a three electrode section and having a focus action stronger in the horizontal direction than in the vertical direction. The dynamic focus voltage which decreases with an increasing deflection amount is reduced. The horizontal diameter of an electron beam spot is reduced on the central area of the screen.

Color cathode-ray tube having a dynamic focus voltage

An electron gun of a color cathode ra tube includes (1) a beam forming region having cathodes, a G electrode and a G electrode and (2) a main lens formed of plural electrodes including a G electrode supplied with a fixed focus voltage and an accelerating electrode. The main lens includes a final lens formed between the accelerating electrode and an electrode opposing the accelerating electrode and configured so that outer electron beats are deflected toward a trajectory of a center electron beam and a lens strength of the final lens weakens with beam deflection The electron gun also has at least one multipole lens located between the final lens and the beam forming region and configured so as to change a cross sectional shape of the electron beams with beam deflection, and a lens formed between a pair of electrodes located between the final lens and the beam forming region and having axially spaced opposing surfaces each having opposing center beam apertures and opposing outer beam apertures. The centers of the opposing outer beam apertures in the opposing surfaces are displaced from each other in a direction perpendicular to the electron gun axis. The lens formed between the pair of electrodes focuses the electron beams in both horizontal and vertical directions and changes a focusing strength thereof with beam deflection and deflects the outer electron beams toward or away from the center electron beam with beam deflection.

Color cathode ray tube having a low dynamic focus

A color cathode ray tube has G1-G5 electrodes and an anode. The G5 electrode is divided into sub-electrodes supplied alternately with a first fixed focus voltage and a second focus voltage which is a second fixed voltage superposed with a dynamic voltage, at least one electrostatic quadrupole lens is formed between adjacent ones of the sub-electrodes, and two of the sub-electrodes are supplied with the second focus voltage. The following inequalities are satisfied: 0.0625&times;L (mm)&lE;B&minus;20A/(3&phgr;)&lE;22.0 mm, L (mm)&lE;352 mm, where A is an axial length of the G4 electrode, &phgr; (mm) is an average diameter of a center aperture in the G4 electrode, B (mm) is a length from a cathode side end to a phosphor screen side end of said G5 electrode to the phosphor screen.

Color cathode ray tube with a reduced dynamic focus voltage for an electrostatic quadrupole lens thereof

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Mobara, Japan

Shoji Shirai