Patents Assigned to Hitachi Electronic Devices
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Patent number: 6476544Abstract: A color cathode ray tube includes an electron gun having cathode structures arrayed in line with a cup-shaped first grid electrode. Each of the cathode structures is fused and fixed to a cathode in an electrically insulated state by hermetic glass. A cathode support to which the cathode structures are fixed by glass is fixedly housed in the cup-shaped first grid electrode, and the first grid electrode and the cathode support are welded on an axis along which the cathode structures are arrayed. The cathode structures and the first grid electrode are welded on an inline axis so that the thermal deformation of the cathode support can be made uniform at the center portion and at side portions. Accordingly, at the start-up time of the color cathode ray tube, the cathode currents at the center portion and at the side portions can be equalized and a good color balance can be maintained on the screen.Type: GrantFiled: March 9, 2000Date of Patent: November 5, 2002Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Sakae Ishii, Yasuhisa Shiraishi, Satoru Miyamoto
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Patent number: 6476543Abstract: A cathode ray tube has a phosphor screen and an electron gun. The electron gun includes an electron beam generating section and an electron beam focusing section for focusing an electron beam from the electron beam generating section onto the phosphor screen. The electron beam generating section and the electron beam focusing section are mounted in predetermined spaced relationship on plural insulator support rods. The electron beam focusing section includes at least one compound electrode formed of a first electrode member, a second electrode member and a plate-like electrode member sandwiched therebetween. The plate-like electrode member is fabricated from a material thicker than materials from which the first and second electrode members are fabricated. The plate-like electrode member is laser-welded to the first and second electrode members at points of edges of the first and second electrode members.Type: GrantFiled: October 30, 2000Date of Patent: November 5, 2002Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co.,Inventors: Takeshi Mera, Yoshifumi Konishi, Ken Kagabu, Akihito Sudo
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Patent number: 6465942Abstract: A color cathode ray tube includes a generally rectangular shadow mask having a curved apertured portion having a multiplicity of electron-transmissive apertures, a curved imperforate portion surrounding and integral with the apertured portion and a skirt portion bent back from a periphery of the curved imperforate portion, and a generally rectangular support frame for suspending the shadow mask by spot welding the skirt portion thereto, within a panel portion of the color cathode ray tube. The skirt portion is provided with a plurality of embossments and is fitted inside the support frame. The embossments protrude inwardly and extend in a direction of a height of the skirt portion. A distance between a bottom of each of the plurality of embossments and a border of the curved apertured portion is at least 4.5 mm.Type: GrantFiled: June 22, 2001Date of Patent: October 15, 2002Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Hiroshi Ito, Koji Hagiwara
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Patent number: 6437497Abstract: A color cathode ray tube includes a rectangular shadow mask made of an Fe-Ni alloy material, and having an apertured portion, an imperforate portion surrounding the apertured portion and a skirt portion bent back from the imperforate portion, and a rectangular support frame for suspending the shadow mask by spot welding the skirt portion thereto. The skirt portion is provided with plural slits and plural embossments extending in a direction of the height of the skirt portion in one of long and short sides of the skirt portion, and the slits and embossments are juxtaposed around a circumference of the skirt portion. A majority of the slits in the one of the long and shirt sides of the skirt portion are slits delimiting continuous openings in the skirt portion which are not bridged by members other than the support frame.Type: GrantFiled: July 25, 2001Date of Patent: August 20, 2002Assignees: Hitachi, Ltd., Hitachi Electronics Devices Co., Ltd.Inventors: Hiroshi Ito, Nobuhiko Hosotani, Masahiro Ito, Koji Hagiwara
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Patent number: 6417610Abstract: A color cathode ray has an electron gun which includes three cathodes for emitting three in-line electron beams and a plurality of electrodes fixed in a predetermined axially spaced relationship on insulating supports. At least one of the plurality of electrodes is cup-shaped and has a correction electrode therein, and edges of the correction electrode are formed with recesses and sloped portions. A distance L from a mouth of each of the recesses of the correction electrode to an inner wall of the at least one of the plurality of electrodes satisfies the following relationship: L′≦L≦15 &mgr;m, where L′ is a height of a burr caused in press-forming of the recesses.Type: GrantFiled: May 18, 2000Date of Patent: July 9, 2002Assignees: Hitachi, Ltd., Hitachi Electronics Devices Co., Ltd.Inventors: Akihito Sudo, Satoshi Moriwaki, Mitsuhiro Sugiyama
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Patent number: 6353281Abstract: A color cathode ray tube including a panel section having a phosphor layer formed on an internal surface thereof, a neck portion having an electron gun assembly for emission of three electron beams therein, and a funnel section connecting the panel section and the neck portion. The electron gun assembly includes three cathodes and a plurality of grid electrodes disposed along a tube axis. The grid electrodes includes at least one plate-shaped electrode which has a fixed support structure. The plate-shaped electrode has three bulged portions along an electron beam passage, a first electron beam passage hole being formed in a respective bulged portion and a second electron beam passage being hole formed in a top face portion of a respective bulge portion. A diameter of the first electron beam passage hole is greater than a diameter of the second electron beam passage hole.Type: GrantFiled: April 13, 2001Date of Patent: March 5, 2002Assignees: Hitachi, Ltd., Hitachi Device Engineering, Co., Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Mitsuhiro Sugiyama, Tsutomu Tojyo, Masahiro Ito, Masayoshi Misono, Hiroyuki Tamura
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Patent number: 6334689Abstract: A liquid crystal display includes a liquid crystal display panel having a plurality of liquid crystal cells and aback light that irradiates the liquid crystal display panel with irradiation light. The back light includes a light source and a light guide plate having one side arranged adjacent the light source and having a planar surface with a plurality of small concaves. The planar surface is substantially parallel to a liquid crystal cell face and a plane shape of the small concaves is substantially rectangular.Type: GrantFiled: February 25, 1999Date of Patent: January 1, 2002Assignees: Hitachi, Ltd., Hitachi Electronics Devices Co., Ltd.Inventors: Hitoshi Taniguchi, Yasuo Hira, Yuji Mori, Hisao Hirayama, Toshitsugu Miyawaki
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Patent number: 6331064Abstract: A liquid crystal display is formed by a liquid crystal display panel for modulating light to form an image, and a back light unit including a lamp tube which is discharged by an electrode and is disposed behind said liquid crystal display panel, wherein said electrode is formed outside of said lamp tube. In this way, the liquid crystal display unit has a life span which can be increased without the need to replace the lamp tube or the back light unit.Type: GrantFiled: November 26, 1999Date of Patent: December 18, 2001Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Seiichi Nishiyama, Shigetake Takaku, Yoshiharu Takeda, Shigeo Mikoshiba, Tomokazu Shiga, Koji Hashimoto
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Patent number: 6313576Abstract: 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.Type: GrantFiled: February 23, 2000Date of Patent: November 6, 2001Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Shoji Shirai, Kenichi Watanabe, Masayoshi Furuyama
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Patent number: 6294872Abstract: A color cathode ray tube is provided with an electron gun having a voltage-dividing resistor having a stable and good voltage supplying function. The voltage-dividing resistor has an insulating substrate on which a resistor pattern and a terminal-connecting conductive film are formed, and a terminal having a first flange portion, a connecting portion, a tubular portion and a second flange portion. The first flange portion partly has a convex portion for electrical connection to the terminal-connecting conductive film, and the second flange portion is doubled. This construction provides reliable electrical connection between the terminal and the terminal-connecting conductive film.Type: GrantFiled: March 9, 2000Date of Patent: September 25, 2001Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Atsushi Tsuruoka, Sakae Ishii, Hisao Nakamura, Satoru Miyamoto
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Patent number: 6274974Abstract: A color cathode ray tube including a generally rectangular shadow mask with at least a long side, a short side and a corner, and having a curved apertured portion with a multiplicity of electron-transmissive apertures, a curved imperforate portion surrounding and integral with the apertured portion and a skirt portion bent back from a periphery of the curved imperforate portion. A generally rectangular support frame is provided for suspending the shadow mask by spot welding the skirt portion thereto within a panel portion of the color cathode ray tube. The skirt portion is provided with a plurality of slits extending in a direction of a height of the skirt portion and a plurality of embossments extending in the direction of the height of the skirt portion in one of a long side and a short side of the skirt portion.Type: GrantFiled: February 16, 2000Date of Patent: August 14, 2001Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Hiroshi Ito, Nobuhiko Hosotani, Masahiro Ito, Koji Hagiwara
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Patent number: 6255765Abstract: A color cathode ray tube includes a generally rectangular shadow mask having a curved apertured portion having a multiplicity of electron-transmissive apertures, a curved imperforate portion surrounding and integral with the apertured portion and a skirt portion bent back from a periphery of the curved imperforate portion, and a generally rectangular support frame for suspending the shadow mask by spot welding the skirt portion thereto, within a panel portion of the color cathode ray tube. The skirt portion is provided with plural embossments extending in a direction of a height of the skirt portion, and the embossments are distributed over each of central portions extending a distance PHL and a distance PVL in long and short sides of the skirt portion, respectively, PHL and PVL satisfying following inequalities: 0.5 HL≦PHL≦0.85 HL, 0.5 VL≦PVL≦0.Type: GrantFiled: April 22, 1999Date of Patent: July 3, 2001Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co. Ltd.Inventors: Hiroshi Ito, Koji Hagiwara
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Patent number: 6232711Abstract: A color cathode ray tube includes a panel section having an internal surface with a phosphor layer formed thereon and a neck portion accommodating therein an electron gun assembly for emission of a plurality of electron beams plus a funnel section connecting the panel section and the neck portion together, wherein the electron gun assembly is designed to have a plate-shaped electrode with a plurality of electron beam passage holes corresponding in the number to the electron beams. The plate electrode has cylindrical bulged portions projecting in a way corresponding to the plurality of electron beams, each of which portion has its top face in which an electron beam opening or hole is formed. The present invention provides a color cathode ray tube comprising a readily manufacturable high-resolution electron gun assembly.Type: GrantFiled: December 14, 1999Date of Patent: May 15, 2001Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Mitsuhiro Sugiyama, Tsutomu Tojyo, Masahiro Ito, Masayoshi Misono, Hiroyuki Tamura
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Patent number: 6111346Abstract: A color cathode ray tube includes a generally rectangular shadow mask having a curved apertured portion having a multiplicity of electron-transmissive apertures, a curved imperforate portion surrounding and integral with the apertured portion and a skirt portion bent back from a periphery of the curved imperforate portion, and a generally rectangular support frame for suspending the shadow mask by spot welding the skirt portion thereto, within a panel portion of the color cathode ray tube. The skirt portion is provided with a plurality of slits extending in a direction of a height of the skirt portion and a plurality of embossments extending in the direction of the height of the skirt portion, and the slits and the embossments are juxtaposed around a circumference of the skirt portion.Type: GrantFiled: March 6, 1998Date of Patent: August 29, 2000Assignees: Hitachi, Ltd., Hitachi Electronic Device Co., Ltd.Inventors: Hiroshi Ito, Nobuhiko Hosotani, Masahiro Ito, Koji Hagiwara
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Patent number: 5936338Abstract: A color display system includes a color cathode ray tube having an electron gun having at least a cathode, a control electrode, an accelerating electrode, a focus electrode and an anode. The focus electrode includes a first focus electrode, a second focus electrode and a third focus electrode. The first focus electrode faces the accelerating electrode, a first quadrupole lens is formed in at least one of opposing ends of the first and second focus electrodes.Type: GrantFiled: July 29, 1997Date of Patent: August 10, 1999Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventor: Yoshiaki Takahashi
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Patent number: 5886759Abstract: In order to provide a liquid crystal display (LCD) device capable of improving the display quality by preventing light leakage in the end portion of a display window on the side adjacent a fluorescent tube, a liquid crystal display device has a LCD panel, a light guide placed under the LCD panel, a fluorescent tube placed close to and along at least one side of the light guide, a lamp reflector sheet for covering substantially the whole length of the fluorescent tube, a diffusion sheet placed on the light guide under the LCD panel, and a reflective sheet placed under the light guide, wherein the surface of the lamp reflector sheet, reflective sheet or the diffusion sheet on the one side of the light guide is printed in color.Type: GrantFiled: March 6, 1996Date of Patent: March 23, 1999Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co. Ltd.Inventors: Naohiro Mashino, Hisao Hirayama
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Patent number: 5872423Abstract: A color cathode ray tube includes a panel portion having a phosphor screen on its inside surface and suspending a shadow mask hanged closely spaced from the phosphor screen, a neck portion for housing an electron gun, and a funnel portion for connecting the panel portion to the neck portion. The electron gun is composed of a first plurality of grid electrodes spaced specified distances apart and arranged axially in a specified order, respectively, and fixed by insulating rods embedding the first plurality of grid electrodes therein, including a cup-shaped first grid electrode having a second plurality of in-line electron beam apertures in a bottom thereof and having the second plurality of cathodes incorporated therein. The cup-shaped first grid electrode is embedded in the insulating rods through metal tabs fixed thereto, and a thermal expansion coefficient T1 of the metal tabs and a thermal expansion coefficient T2 of the cup-shaped first grid electrode satisfy the following inequality, T1>T2.Type: GrantFiled: August 25, 1997Date of Patent: February 16, 1999Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Yasuhisa Shiraishi, Shinichi Ishinagawa, Sakae Ishii
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Patent number: 5861716Abstract: A magnetron includes a cathode mount having a directly heated helical cathode filament for emitting thermoelectrons, an upper end shield and a lower end shield disposed so as to support the filament at upper and lower ends thereof, and center and side leads holding the upper and lower end shields respectively. The lower end shield is formed with a recess for housing the lower end of the directly heated helical cathode filament in the upper surface thereof, at least a portion of the inner wall of the recess is sloped, and a groove is formed at the peripheral edge of the bottom of the recess.Type: GrantFiled: February 13, 1996Date of Patent: January 19, 1999Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventor: Toshio Ogura
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Patent number: 5847500Abstract: In an electron gun for a cathode ray tube in which a focus electrode group includes a single platelike electrode having three apertures arrayed in one plane and a thickness equal to a depth of each of the three apertures, a tapered surface is formed on the entrance side and/or exit side of each of the three apertures, the tapered surface having a diameter larger than the aperture diameter and having a linear or curved shape in cross section, and a step which extends in the direction of the depth is formed around an aperture periphery of the tapered surface. With this constitution, the concentricity between each of the tapered surfaces and a respective one of the apertures can be measured with high precision on the basis of the boundary between each of the tapered surfaces and the corresponding one of the steps, thereby improving the precision of measurement of the concentricity between each of the apertures formed in the platelike electrode and the tapered surface formed around the aperture periphery.Type: GrantFiled: March 1, 1996Date of Patent: December 8, 1998Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Takeshi Mera, Masato Miura, Yoshiaki Takahashi
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Patent number: 5798603Abstract: A cathode ray tube includes an evacuated envelope having a panel portion carrying a phosphor screen, a neck portion housing an electron gun and a funnel portion for connecting the panel portion and neck portion, the electron gun housed in the neck portion and a deflection device mounted in a transition region between the funnel portion and neck portion. The electron gun is provided with an electrode having a single opening common to the three electron beams and having correction electrodes disposed in vicinities of both edges of the single opening in the inline direction and extending substantially parallel with a cathode ray tube axis into a region downstream of an end surface of an anode electrode forming a main lens on a cathode side thereof and provided with electric field produced by the main lens, and the electrode having the single opening is electrically connected to the anode electrode.Type: GrantFiled: March 8, 1996Date of Patent: August 25, 1998Assignees: Hitachi, Ltd., Hitachi Electronic Devices Co., Ltd.Inventors: Atsushi Tsuruoka, Masayoshi Misono