Sony Corporation

Candescent Technologies Corporation

Yukinobu Iguchi

Ichiro Utsumi

Nobuya Okano

Tsunenari Saito

Koji Saita

Hiromu Hosokawa

Yoshifumi Nakayama

James Montague Cleeves

Christopher J Spindt

James C Dunphy

Hiroshi Murayama

Hiroyuki Ikeda

Masahiro Kikuchi

Ronald L Hansen

Tsuneo Muchi

Yutaka Ota

Kunihiko Nagamine

Koji Hasegawa

Shinji Kanagawa

Jerome M Truppa

Hiroki Anzai

Kanemitsu Murakami

Yasuhito Hatano

Kouji Hasegawa

Youichi Ohshige

Gregory M Fink

Tomohisa Asano

A method for driving a flat-type display device which includes a cathode panel having first electrodes and second electrodes and an anode panel, the cathode panel and the anode panel having spacers is provided. The method includes the steps of: in the non-display operation period of the flat-type display device, determining a normalized first current from a first current by non-display-driving the electron emitter areas near the spacers, and determining a normalized second current from a second current by non-display-driving the electron emitter areas which are not near the spacers; and in the actual display operation period of the flat-type display device, setting the driving conditions for the electron emitter areas on the basis of the normalized first current and normalized second current so that the electron emission conditions in the electron emitter areas near the spacers and not near the spacers are substantially the same.

Method for driving a flat-type display device

A color picture tube is provided with a glass bulb in which the external surface of the effective display area of the face plate is formed substantially flat and a color selection mask, having the curvature projected toward the face plate, provided opposed to the internal surface of the face plate within the glass bulb. Therefore, the external surface is flat, the mechanical shock resistance characteristic is high, a tension can surely be applied to the color selection mask and moreover vibration of the color selection mask can be prevented even if external vibration is applied thereto.

Glass bulb for color picture tube and the same tube

A field emission display (FED) having a correction system with a correction coefficient derived from emission current is presented. Within one embodiment in accordance with the present invention, a field emission display has an anode at the faceplate and a focus structure. The anode potential is held at ground while the focus structure potential is held between, but is not limited to, 40 and 50 volts. The current flowing to the focus structure is measured and used as the basis for the correction coefficient for the field emission display.

System and method for recalibrating flat panel field emission displays

To prevent lowering of the brightness of a displayed image, realize satisfactory strength against high pressure and reliably form spacers, an image display apparatus incorporates an anode substrate having a structure in which at least an image display portion is formed on a first substrate; a cathode substrate in which at least an electron emission units are formed on a second substrate and which is disposed opposite to the anode substrate; and spacers each of which formed into a substantially rectangular shape and which are stood erect between the anode substrate and the cathode substrate, wherein the two long sides of the spacer are secured to at least either of the anode substrate or the cathode substrate, and tensions are added to the spacers in the lengthwise direction of the spacers.

Image display apparatus with rectangular-shaped spacers having added tensions

A main lens member for an electron gun comprises at least one high electrical resistance layer formed of a higher electrical resistance material sandwiched between low electrical layers which are laminated together to form a main line of an electron gun.

Luminated main lens member for an electron gun

A cathode ray tube includes a sixth grid (G.sub.6), which is a final accelerating electrode, of first to sixth grids (G.sub.1 to G.sub.6) forming an electron gun and the sixth grid (1) is divided into three electrodes (G.sub.6a, G.sub.6b and G.sub.6c). Longitudinally oblong opening portions (9 and 11) are formed through the first and third electrodes (G.sub.6a and G.sub.6c), and a laterally oblong opening portion (10) is formed through the second electrode (G.sub.6b). A dynamic voltage is supplied to the electrode (G.sub.6b) through a neck capacitor (19) formed at a neck portion (2a) of the cathode-ray tube (2) to thereby form a quadrupole-lens electric field (7) for correction of deformation of a beamspot on the side of a deflection yoke relative to a main-lens electric field (8).

Cathode-ray tube with electric field correction lens for improved

An electron gun for a color CRT has three cathodes disposed in parallel to each other, first to fifth grid electrodes and a convergence deflector. The electron gun is additionally provided with a tetrode magnetic field generator including a pair of permanent magnets having an astigmatic effect of the central beam of the electron gun on the cathode side of the convergence deflector. An astigmatism eliminator is provided to cancel astigmatic aberration of the side beams of the electron gun near the position where the electron beams are converged. The astigmatism eliminator is composed of a fifth grid electrode whose entrance has an electron beam passing hole of nearly elliptic shape.

Electron gun for color cathode-ray tube

A dynamic convergence device in a color cathode-ray tube has two pairs of confronting high- and low-voltage electrode plates disposed in a color cathode-ray tube bulb and arranged such that a central electron beam will pass between the high-voltage electrode plates and side electron beams will pass between the high-voltage electrode plates and the low-voltage electrode plates. A first parallel-connected circuit is composed of a first resistor and a first diode which are connected between the low-voltage electrode plates and a high DC voltage source. A second parallel-connected circuit is composed of a second resistor and a second diode which are connected between the high-voltage electrode plates and the high DC voltage source. A convergence voltage source generates a convergence voltage which is composed of a vertical parabolic wave voltage added to a modulated voltage in horizontal blanking intervals thereof which is produced by amplitude-modulating a horizontal parabolic wave with a vertical parabolic wave. A first capacitor is connected between the convergence voltage source and the low-voltage electrode plates or the high-voltage electrode plates, and a second capacitor is connected between the low-voltage electrode plates or the high-voltage electrode plates and ground.

Dynamic convergence device for color cathode-ray tube

A cathode-ray tube has an electron gun sealed in a neck in confronting relationship to the phosphor screen. The electron gun comprises a cathode assembly for emitting three electron beams, a main lens region for passing the electron beams therethrough, the main lens means including a high-voltage electrode or grid closer to the phosphor screen, and an assembly of electrostatic deflection plates, positioned closer to the phosphor screen than the high-voltage electrode, for converging the electron beams as one spot on the phosphor screen. An electrostatic convergence electrode assembly is disposed between the high-voltage electrode and the deflection plates. The electrostatic convergence electrode assembly may comprise three or two juxtaposed flat electrodes having electron beam passage holes. The voltages applied to the high-voltage electrode and the deflection plates are also applied selectively to the three or two electrodes of the electrostatic convergence electrode assembly for applying an astigmatic effect equally to the electron beams.

Cathode-ray tube with electrostatic convergence electrode assembly

An electron beam for a color CRT is equipped with three cathodes such that three electron beams may be emitted therefrom. Three grids are provided with beam passing holes for each of the three electron beams and are positioned in the path of the electron beams. The beam passing openings of the third grid are shifted from alignment with the beam passing openings of the first and second grid by a degree sufficient to focus the three beams appropriately relative to a central focal axis of the electron gun.

Three gun color CRT which has three grids with the holes in the third

A dynamic convergence apparatus of a simplified arrangement can reduce a distortion of a beam spot on a periphery of a picture screen and improve a focusing, wherein a parallel circuit of a high resistance value resistor (R) and a diode (D) is connected between low voltage side electrode plates (3), (4) and high voltage side electrode plates (1), (2) to which an anode voltage (HV) is applied, a capacitor (C) is formed by coating a conductive layer on the inside and outside of a tube envelope of a color CRT while glass of the tube envelope is used as a dielectric material, and a convergence voltage which results from adding a vertical parabolic wave voltage to the horizontal blanking period of a modulated voltage provided by amplitude-modulating a DC voltage very slightly lower than the anode voltage (HV) by horizontal and vertical parabolic waves is commonly supplied from one end side (outside of the tube envelope) of the capacitor (C) to the low voltage side electrode plates (3), (4).

Convergence correction circuit for cathode ray tube

A cathode-ray tube has an electron gun disposed in its neck in confronting relationship to a phosphor screen through a deflection yoke mounted on the funnel. The electron gun has a cathode assembly for emitting three electron beams, and a main lens for passing the electron beams therethrough. The main lens includes a quadruple lens system responsive to focusing voltages for canceling an astigmatic effect produced on the electron beams when the electron beams are deflected by the deflection yoke, at a peripheral edge of the phosphor screen. The cathode-ray tube also has a first quadruple convergence yoke lens system disposed between the main lens and the deflection yoke for generating an astigmatic effect which is opposite to the deflection-induced astigmatic effect, and a second quadruple convergence yoke lens system disposed between the emitting means and the main lens means for generating an astigmatic effect which is in the same direction as the astigmatic effect generated by the first quadruple convergence yoke lens system.

Cathode-ray tube with convergence yoke lens systems

An improved electron gun beam for a three color gun which has a central cathode and side cathodes mounted on either side of the central cathode which produce beams for different colors which pass through first and second grids and a main electron lens and wherein the first and second grids are generally conically shaped so that they extend toward the central cathode and have further indentations in their central portion which extend toward the central cathode and wherein the thickness of the second grid at the center wherein the beam of the central cathode passes therethrough is less than at the portions of the second grid where the beams from the two side cathodes pass therethrough and also where the distance between the central cathode and the indented portion of the first grid is larger than the distance between the two side cathodes and the distance to the first grid and/or the distance between the second and first grids is larger at the portion where the central cathode beam passes therethrough than where the beams of the two side cathdoes pass therethrough so as to provide optimum focusing voltage values and the voltage difference for optimum focusing for the respective beams is constand over the entire cathode current operating ranges.

Growing community of inventors

Kanagawa, Japan

Yukinobu Iguchi