Abstract: A steak tube 1 has a container 2 with an entrance plate 2a and an output plate 2b; a photocathode 7 disposed in the container 2 and configured to emit electrons according to light to be measured, the light having been incident through the entrance plate 2a; a mesh electrode 3, a first focusing electrode 4, and an aperture electrode 5 forming an axially symmetric electron lens for focusing the electrons emitted from the photocathode 7, toward the output plate 2b; a sweep electrode 6 disposed in the container 2 and configured to sweep the electrons focused by the axially symmetric electron lens, in a sweep direction along the output plate 2b; and a second focusing electrode 9 disposed between the entrance plate 2a and the output plated 2b and forming a one-dimensional electron lens for focusing the electrons in the sweep direction.

Abstract: A spark plug includes a tubular metallic shell; a tubular insulator in the tubular metallic shell located at a front end of the metallic shell and having an axial hole extending in the axial direction; and a center electrode inserted into the axial hole. The center electrode has a space-forming portion which forms, in cooperation with a wall surface of the axial hole, an annular space open frontward in the axial direction, and a main body portion extending rearward from the rear end of the space-forming portion. The thickness of the insulator is 0.6 mm or less as measured on a cross section and contains the front end of the metallic shell. The axial distance between the boundary portion and the front end of the metallic shell is 0.4 mm or greater, where the boundary portion is formed between the space-forming portion and the main body portion.

Abstract: A variety of systems, apparatus and methods for deflecting a particle beam are described. An apparatus comprises at least six electromagnetic portions disposed on a plane. Each of the at least six electromagnetic portions is aligned with a radius emanating from an axis normal to the plane and is distanced from the axis to form a volume about the axis. At least six coils are configured for affecting a dipole magnetic field in the volume in response to electrical currents applied to physically opposing coils where a particle beam entering the volume is deflected. Each of the at least six coils is disposed about a one of the at least six electromagnetic portions. A yoke structure is configured for returning a generated magnetic flux.

Abstract: An electron gun includes an electron source configured to emit electrons. The electron source includes an electron emission region configured to emit the electrons and an electron emission restrictive region configured to restrict emission of the electrons. The electron emission restrictive region is located on a side surface of the electron source except an electron emission surface on a tip of the electron source and is covered with a different material from the electron source. The electron gun emits thermal field-emitted electrons by applying an electric field to the tip while maintaining a sufficiently low temperature to avoid sublimation of a material of the electron source. The material of the electron source may be lanthanum hexaboride (LaB6) or cerium hexaboride (CeB6). The electron emission restrictive region may be covered with carbon.

Abstract: An electron emitting-device is provided that comprises a plurality of electron emission portions; and a plurality of deflection electrodes for deflecting electrons emitted from the plurality of electron emission portions, wherein each of the plurality of deflection electrodes deflect the emitted electrons toward the same deflection direction. One of the plurality of deflection electrode, which is positioned at an end of the deflection direction, less deflect the emitted electrons than other one of the plurality of deflection electrode, which is positioned at an opposite end of the deflection direction.

Abstract: A device which employs an electron beam, for performing a desired function, includes an electron gun for generating the electron beam. The electron gun includes a barrel shaped rotatable structure having a plurality of annularly disposed electron sources. A curvature of a surface portion of the rotatable structure is shaped to optimize electric field concentrations. The rotatable structure further includes end portion protrusions.

Abstract: A plurality of magnet rings for correcting a convergence are arranged in a tube axis direction with spacers interposed therebetween, on an outer circumferential surface of a neck. A velocity modulation coil for modulating a scanning velocity in a horizontal direction of an electron beam is placed so that a position of the velocity modulation coil in the tube axis direction is overlapped with those of the magnet rings. At least one of the spacers is made of only a magnetic substance. Alternatively, at least one of the spacers is made of a magnetic substance, and the outermost surface in a radius direction of the spacer made of a magnetic substance is covered with a non-metallic material. Because of this, the magnetic field formed by the velocity modulation coil can be intensified without disturbing the magnetic field of the magnet rings of a CPU.

Abstract: An insulating frame of a deflection yoke is fixed to a funnel with a metal band and a metal screw. A partition formed so as to be integrated with a holder holding a magnet ring of a CPU includes a first partition provided on a first axis so as to hide the metal screw when the deflection yoke is seen from the holder side along a tube axis, and a second partition provided on a second axis orthogonal to the first axis. A height H1 of the first partition, a height H2 of the second partition, a minimum height Hmin of the partition, a height HM of a pull of a magnet ring on a side closest to the deflection yoke, and an outer circumferential edge diameter RM of the magnet ring excluding the pull satisfy relationships: H1>H2, HM?H2>10 mm, and Hmin>RM. Because of this, a discharge between a metal band and a metal screw that fix the deflection yoke, and a velocity modulation coil can be prevented without decreasing the operability of the rotation adjustment of the magnet ring of the CPU.

Abstract: An electron beam pumped laser including a surface-emitting laser faceplate oriented at a non-perpendicular angle. Embodiments are described in which a bending coil bends the electron beam, or in which the faceplate is situated in the direct path of the e-beam emission but with a non-zero orientation angle. The faceplate may include a substantially opaque substrate, and an opaque heat-removing structure may be attached to the substrate to provide high heat transfer, thereby allowing high electron-beam pumping intensity and providing more light emission from a smaller package. In some embodiments the partially reflective mirror comprises a metal layer that has a plurality of openings. Multiple laser faceplates (e.g., red, green, and blue) may be placed in the same tube, to provide a continuous light source for projection television. The substrate may be connected to ground to provide an exit path for electrons from the laser gain layer.

Abstract: A deflection yoke includes ferrite core, horizontal deflection coil, vertical deflection coil, and insulating frame for insulating the horizontal and vertical deflection coils. The deflection yoke has a cross section that satisfies the following A to C. A: A plurality of magnetic substance convex portions projecting toward the tube axis are provided in the vicinity of a position of an inner surface of the ferrite core where a vertical axis crosses. B: Assuming that a minimum value among distances between the respective magnetic substance convex portions and a funnel is D1, the distance between the ferrite core excluding the plurality of magnetic substance convex portions and the funnel is larger than the distance D1 at any point of the ferrite core. C: A part of the vertical deflection coil is wound in a groove between the plurality of magnetic substance convex portions.

Abstract: An electron beam apparatus including an electron gun for directing a plurality of primary electron beams onto a sample, an objective lens for forming an electric field to accelerate a plurality of secondary electron beams emitted from the sample, and a separator for separating the plurality of secondary electron beams from a primary optical system and for directing the plurality of secondary electron beams into a secondary optical system for guiding to a detector outputting a detection signal of the secondary electron beams. A deflector deflects the secondary electron beams in the secondary optical system. The deflector is controlled to deflect the plurality of secondary electron beams synchronously with scanning of the plurality of primary electron beams, thereby preventing the plurality of secondary electron beams from moving on the detector in response to the scanning of the plurality of primary electron beams.

Abstract: A deflection coil for deflecting an electron beam emitted from an electron gun is provided outside a cathode-ray tube in which the electron gun is housed, and a phosphor screen is formed. The cathode-ray tube further includes a velocity modulation coil for modulating a horizontal scanning velocity of an electron beam, a first magnetic substance surrounding an outer circumference of the cathode-ray tube from outside the velocity modulation coil, and a second magnetic substance surrounding the outer circumference of the cathode-ray tube between the deflection coil and the first magnetic substance. Because of this, the sensitivity of velocity modulation can be enhanced effectively with a simple configuration while deflection distortion is prevented.

Abstract: The present invention relates to a color cathode ray tube and electron gun, and more particularly, to a color cathode ray tube and electron gun to improve deflection aberration efficiently using magnetic material formed at the electron gun and to improve a resolution of a display screen.

Abstract: An electron gun for a color CRT includes a main focusing lens unit that focuses the electron beams generated by a triode unit. The main focusing lens unit includes a first and a second electrostatic screen grid having three electron beam through holes linearly-arranged for passing three electron beams, two of the holes being external and an oval shaped hole that passes all three electron beams. The oval shaped holes being spaced a distance, d1 and d2, respectively, from the through holes. Furthermore, the first grid external holes have an external distance HL1 and an internal distance HR1 and the second grid external holes have an external distance HL2 and an internal distance HR2; and wherein HL1 is greater than HR1, HL2 is greater than HR2, d1 is greater than d2, HL2 is greater than HL1, and HL2+HR2 is greater than HL1+HR1.

Abstract: A deflection apparatus for a cathode ray tube includes a horizontal deflection coil, a vertical deflection coil positioned external to the horizontal deflection coil, an insulating member interposed between the horizontal and the vertical deflection coils, and a core placed on the insulating member while being connected to the vertical deflection coil. The horizontal deflection coil, the vertical deflection coil, the insulating member and the core have at least one sectional structure proceeding perpendicular to the tube axis of the cathode ray tube. With any one of the horizontal and the vertical deflection coils, the sectional structure is formed with a combination of arcs corresponding to a horizontal axis X, a vertical axis Y and a diagonal axis between the horizontal and the vertical axes X and Y. The arc corresponding to the horizontal axis X or the vertical axis Y is formed with an arc centering around a point on the axis other than the horizontal axis X or the vertical axis Y.

Abstract: The present invention relates to a flat panel display, and more particularly, to a flat panel display in which the main skeletal structure of a horizontal deflecting electrode is arranged in a horizontal direction to enhance structural strength and the structure of an electrode to which voltage is applied is shaped symmetric to eliminate over-converging of electron beam.

Abstract: An electron gun for a cathode ray tube includes a cathode for radiating electron beams, a scanning velocity modulation coil for synchronizing the electron beams with an image signal, a focus electrode having first and second sub-electrodes disposed with a gap through which a magnetic field generated by the scanning velocity modulation coil passes, a plurality of grid electrodes with the focus electrode for controlling the electron beams radiated from the cathode, a support for aligning and supporting the grid electrodes, and a shield electrode electrically connected to the first and second sub-electrodes to protect against infiltration of an outer electric field. The shield electrode includes plural intermediate electrodes disposed in the gap between the first and second sub-electrodes, and electrical connecting unit for electrically connecting the intermediate electrodes to the first and second sub-electrodes. The intermediate electrodes are spaced away from each other.

Abstract: The invention provides a deflection yoke device comprising a main yoke portion 4 for deflecting an electron beam emitted by an electron gun, and a convergence yoke portion 5 for adjusting the convergence of the electron beam. The convergence yoke portion 5 comprises an annular convergence core 53, a convergence horizontal coil 51 wound around both of left and right two regions of the core 53 which intersect a horizontal axis, and a convergence vertical coil 52 wound around both of upper and lower two regions of the core 53 which intersect a vertical axis. Short-circuited coils 54, 54 are provided around the respective left and right two regions of the core 53.

Abstract: The present invention relates to a display device comprising a cathode ray index tube (1) having a neck portion (1?) and a screen portion (1). The display device comprises an electron gun assembly (3) for generating a plurality of electron beams (3R,3G,3B), positioned in the neck portion (1?) of the cathode ray index tube (1), a deflection unit (5), placed around the neck portion (1?) of the cathode ray index tube (1), for deflecting said plurality of electron beams (3R,3G,3B), and a convergence unit (6) for converging said plurality of electron beams (3R,3G,3B). The deflection unit (5) is placed at an axial distance from said electron gun assembly (3), closer to said screen portion (1?). The convergence unit (6) is placed in close proximity to the deflection unit (5).

Abstract: The present invention relates to a tracking picture tube of the type in which comb-shaped electrodes or optical detecting means (12, 13) are used for generating a signal related to the position of an electron beam with respect to the strips (5). The tube is characterized in that the deflection unit is arranged to deflect the beams (21r, 21g, 21b) onto selected strips (22r, 22g, 22b) having coincident sides which neighbour finger portions (14, 15) of the same electrode (12, 13), and the selected strips (22r, 22g, 22b), excited by the electron beams, are separated by at least one unexcited strip, respectively.

Abstract: Correction of electron beam landing misalignment in a raster-type display is undertaken without using the usual set of coils, but rather by superimposing a landing misalignment correction signal on the already-existing velocity modulation (VM) coil or on another coil located at the junction of the electron beams in the neck of the display. The correction signal may be varied based on pressure, temperature, and ambient magnetic field as indicated by respective sensors to appropriately correct electron beam landing on phosphors the positions of which may be affected by variations in magnetic fields, temperature, and pressure.

Abstract: Apparatus and method are provided for using a multi-element field emission cathode in a color cathode ray tube. The field emission cathode may have from four to ten field emission arrays linearly arranged. The arrays are preferably formed from carbon-based material. An electron gun assembly focuses electron beams from each array on to a phosphor stripe or dot on the screen of the cathode ray tube. Deflection apparatus moves the beam from each field emission array according to clock signals. Clock signals also turn on or turn off voltage to contacts controlling electron current from the array. Values of voltage applied, determined by a video signal, determine the intensity of electron current from each array, which controls the intensity of the light emitted by each color stripe or dot of phosphor on the phosphor screen.

Abstract: An electron gun assembly of a color cathode ray tube emits at least one electron beam having an oblong cross-sectional shape extending substantially in the horizontal direction, and emits three electron beams in a substantially non-convergent state toward the central portion of a phosphor screen. A deflection device comprises an auxiliary magnetic field generator for generating a quadrupole magnetic field component which focuses the electron beam with an oblong cross section more heavily in the horizontal direction than in the vertical direction. The auxiliary magnetic field generator is located in a given region in a tube-axis direction in which the horizontally deflecting coil is located.

Abstract: The present invention relates to a cathode ray tube having a deflection yoke including a circular ferrite core and a deflection coil whose cross-section is in a rectangular shape for improving a deflection sensitivity of the cathode-ray tube, and more particularly to a cathode ray tube, in which one part of a vertical deflection coil having a rectangular shaped cross-section to improve a lead-in capability when winding the vertical deflection coil located between a ferrite core and the holder is separated by a predetermined gap from a holder that isolates a horizontal deflection coil and the vertical deflection coil.

Abstract: Disclosed is a cathode ray tube with an electron gun capable of improving a resolution of an image by preventing electron beams from striking electrodes and efficiently controlling a spot size that is susceptible to a change in current capacity.

Abstract: A color cathode-ray tube including an in-line electron gun and a color cathode-ray tube apparatus including the same are provided. At an end, on a screen side, of the electron gun, two pairs of members for generating a magnetic field are placed above and below side beams of three electron beams so as to sandwich them, respectively. Between each of the two pairs of members for generating a magnetic field, a localized barrel magnetic field is formed to vary cross-sectional shapes of the side beams positioned on both sides of a center beam so that the cross-sectional shape of one of the side beams is horizontally or vertically elongated to a higher degree than that to which the cross-sectional shape of the other of the side beams is. Magnetic fields for reverse correction of spot distortions of the side beams are generated and therefore the symmetry in the spot distortions of the side beams asymmetric with each other is improved, thus improving focus quality.

Abstract: An electron beam trajectory controlling device includes a main deflection section having a first main coil and defining a first path and being configured to control a trajectory of an electron traveling along the first path. The main deflection section includes a first auxiliary coil provided proximate the first main coil. A minor deflection section is provided adjacent to the main deflection section and has a first minor coil that is coupled to the first auxiliary coil. The minor deflection section defines a second electron path that is aligned to the first path. The minor deflection section cooperates with the main deflection section to control the trajectory of the electron.

Abstract: A method and apparatus used to step and correct the position of raster lines in a sinusoidal or zig-zag deflection system. By combining the magnetic flux generated with a rotation “twister” coil and a vertical deflection coil, scan lines can be uniformly spaced and separated nearly to their ends. Accordingly, the magnetic flux generated with the twister coil is adjusted going in the left to right direction then reversed in polarity and readjusted while returning from right to left. It is this controlled twister flux that combines with the linear vertical deflection flux to straighten and then step each scan line to produce an aligned raster.

Abstract: A deflection unit for a cathode ray tube comprises a coil support (5). On its inner surface the coil support 5 comprises protrusions (34) having reference planes in the x-y direction. The coils provided on the inner side of the coil support have lying front flanges (8,9) which have corresponding reference surfaces (31), also extending in the x-y plane, preferably in an inner winding window (51).

Abstract: An electron gun is provided for a color CRT having a triode for emitting, controlling, and accelerating R, G, B beams, and main lens forming electrodes for focusing the R, G, B beams emitted from the triode onto a screen. The electron gun includes first dynamic quadrupole lens forming electrodes for providing a vertical focusing action and a horizontal focusing action to be applied to the R, G, B beams such that the vertical focusing action is different from the horizontal focusing action, and second dynamic quadrupole lens forming electrodes for providing horizontal/vertical focusing actions to be applied to the R, B beams, side beams, and horizontal/vertical focusing actions to be applied to the G beam, a center beam, the horizontal/vertical focusing actions to be applied to the R, B beams being different from the horizontal/vertical focusing actions to be applied to the G beam.

Abstract: 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.

Abstract: A method and apparatus is disclosed for electrostatic deflection and focusing of a charged particle stream. The apparatus can include plural vertical and horizontal deflection plates, although a single vertical and a single horizontal deflection plate each with a reference potential plane are preferred. Both orthogonal and preferably tilted display screens are employed to receive the deflected beam. The particle stream is injected offset from a centered position and the stream is deflected asymmetrically relative to the attracting deflection plate. Two alternately preferred computer programs are employable to calculate an offset position. A preferred external quadrupole is employed to correct any residual astigmatism in the particle stream. In one embodiment, the apparatus is disposed in a cathode ray tube. A reduced footprint CRT is also disclosed. Methods and apparatuses for an energy filtered electron beam, a mass spectrometer and a mass separator are also disclosed.

Abstract: A main lens section of an electron gun assembly includes a focus electrode supplied with a focus voltage of a first level, a dynamic focus electrode supplied with a dynamic focus voltage obtained by superimposing an AC component, which varies in synchronism with deflection magnetic fields, upon a reference voltage close to the first level, and an anode supplied with an anode voltage with a second level higher than the first level. The electron gun assembly further includes at least two auxiliary electrodes disposed between the focus electrode and the dynamic focus electrode, and these at least two auxiliary electrodes are connected via a resistor disposed near the electron gun assembly.

Abstract: In a cathode ray tube apparatus, an electron beam generating section for generating electron beams is composed of a cathode and a plurality of electrodes. Two electrodes of the plurality of electrodes are connected to each other via a resistor. A constant voltage is supplied from the outside of the tube to the one electrode, and a voltage dynamically changed in synchronism with a deflection magnetic field is supplied to an electrode adjacent to the other electrode. Therefore, the shape of a beam spot can be improved, and the resolution of the entire screen can be improved without requiring extensive provision of a lead wire of a stem.

Abstract: In an inline three-beam system color cathode-ray tube, there is provided an inline three-beam system color cathode-ray tube electron gun in which beam spot shapes of three electron beams on the left and right end portions of a fluorescent screen may be uniformed as much as possible and focusing voltages may be adjusted with ease and also deteriorations of beam spot shapes of three electron beams on the left and right end portions of the fluorescent screen may be alleviated and a satisfactory convergence characteristic may be obtained on the whole region of the screen. A color cathode-ray tube electron gun includes trisected focusing electrodes.

Abstract: An electron gun according to this invention includes a cathode having a hemispherical electron-emitting surface, an anode which is arranged to face the cathode, and has a first aperture on the optical axis, and a bias electrode which is arranged between the anode and the cathode, receives a potential lower than one applied to the cathode, and has a second aperture larger than the electron-emitting surface of the cathode on the optical axis. The distal end of the electron-emitting surface of the cathode is arranged in contact with or outside a sphere whose diameter is equal to the diameter of the second aperture of the bias electrode.

Abstract: A color cathode ray tube comprises a panel which outside surface is flat and inside surface has curvature, and a pressed shadow mask having a curved surface opposed to the panel inside surface. The curved surface of the shadow mask is such that the radius of curvature decreases approximately linearly as the position moves from the center to the periphery. Radii of curvature on the major axis, minor axis, and diagonal axis at positions having the same distance from the shadow mask center do not have large differences. This configuration can increase the mechanical strength of the shadow mask.

Abstract: A cathode ray tube includes an electron gun directing electrons towards a faceplate having an electrode biased at screen potential. The electron beam (three beams in a color tube) is magnetically deflected to scan across the faceplate to impinge upon phosphors thereon to produce light depicting an image or information. A first pair of electromagnetic coils forward of the tube neck and deflection yoke is biased by a substantially constant current level to further deflect the electron beam. As a result, the electrons are deflected over a greater total angle than is obtained from the magnetic deflection yoke alone. A further pair of electromagnetic coils proximate the faceplate is biased by an oppositely poled substantially constant current level to direct electrons towards the faceplate, thereby to increase the landing angle of the electrons thereon.

Abstract: A second grid is supplied with a low potential acceleration voltage. A fourth grid and a sixth grid are supplied with a first focus voltage. A third grid and a seventh grid are supplied with a dynamic focus voltage (Vf2+Vd). A prefocus lens having a horizontal and vertical focusing function is formed between the second grid and the third grid. An asymmetrical lens section having a horizontal diverging function and a vertical focusing function is formed between the third grid and the fourth grid. The prefocus lens and the asymmetrical lens section are electrostatically coupled.

Abstract: The disclosed cathode-ray tube has a pyramidal yoke mounting part defined to extend from a joint with the neck to at least the end of a deflection yoke on the side of the screen, the yoke mounting part including: an inside profile having a form protruding towards a tubular axis in the direction of major and minor axes based on a diagonal axis so as to have a functional relation with a deflection angle; and an outside profile having a rectangular form with respect to the major and minor axes, the outside profile having a ratio of a maximum thickness to a minimum thickness on the same axis being either of the minor or major axis in the range from 1.0 to 1.5. It satisfies a relation 0.7<Rov/Roh≦1.0, wherein Roh is a radius of outer curvature in the direction of the major axis and Rov is a radius of outer curvature in the direction of the minor axis.

Abstract: Apparatus for displaying video images including a vacuum envelope which includes a neck portion and a display screen and an electron gun system. The electron gun system producing at least one electron beam, which in response to a magnetic field converges the at least one electron beam onto the display screen causing video images corresponding to the at least one electron beam to be displayed thereon.

Abstract: A cathode-ray tube includes a plate having a first hole on a first surface of the plate and a second hole on a second surface of the plate. The first and second holes coupled together to allow electron beams to pass therethrough. The plate is a unitary structure. The first hole is formed by initiating a first hole formation from the first surface, and the second hole is formed by initiating a second hole formation from the second surface. The first surface is on an opposing side of the second surface.

Abstract: A beam index type cathode ray tube having a screen divided into a plurality of areas and a plurality of electron guns corresponding to the divided screen areas. The beam index type cathode ray tube includes a tube of which inner atmosphere is maintained in a vacuum state and a screen formed at one side of an inner surface of the tube. The screen has phosphor stripes and index stripes. A plurality of electron guns are mounted in the tube facing the screen and a plurality of deflectors are mounted on the tube corresponding to the electron guns to deflect electron beams which are radiated from the electron guns to the screen. A plurality of detectors are mounted on the tube corresponding to the electron guns to sense lights emitted from the index stripes.

Abstract: An electron gun for use in a cathode ray tube (CRT) includes a source of energetic electrons, i.e., a cathode, a beam forming region for forming the energetic electrons into a narrow beam, an arrangement for deflecting the beam over a display screen, and a focus arrangement for focusing the beam on the display screen in the form of a small spot in forming a video image. The beam forming region includes a G1 control grid, a G2 screen grid and a portion of a G3 grid in facing relation to the G2 grid, where each grid includes a respective aperture through which the electron beam is directed, with the apertures aligned along a common axis. The size of the aperture on the side of the G2 grid in facing relation to the G1 grid forms a first focusing lens and is smaller than the size of the aperture on the opposed side of the G2 grid in facing relation to the G3 grid which forms a second focusing lens.

Abstract: 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: −LP+184.9≧LG4≧0.0004 LP3−0.1571 LP2+21.006 LP−922.41, LP≧131.

Abstract: A color cathode ray tube has excellent focusing characteristics over the whole screen thereof, as well as a total length which is short, thus providing a compact monitoring device. The Cathode ray tube has an electron gun in which the ratio between the diagonal size De of a phosphor screen and the distance Lg from the center of the phosphor screen to an end portion of a focusing electrode which forms a main lens portion of the electron gun and faces an anode electrode in an opposed manner is set to De/Lg>1.5. The focusing electrode and the anode electrode have single opening portions whose opening size in the horizontal direction is not less than 68% of the outer diameter of a neck portion and end surfaces of the opening portions face each other in an opposed manner in the tube axis direction along which the electron beams pass.

Abstract: Auxiliary deflection coils are connected to horizontal deflection coils. Each auxiliary deflection coil is disposed in the intermediate region between the inner peripheral end adjacent to a window and the outer peripheral end. Each horizontal deflection coil is dividable into three regions extending from its winding introductory part to its winding terminal part. A variable inductance coil is connected in parallel with the intermediate region to control the horizontal deflection current flowing across the horizontal deflection coil. The variable inductance coil has a cylindrical core installed in a hollow space of a bobbin and a coil connected in parallel with the auxiliary coil. A disc core is provided adjacent to the coil. The disc core has an end face larger in area than an end face of the cylindrical core.

Abstract: A vacuum envelope of a cathode ray tube includes a face panel having a phosphor screen formed on the inner surface, a funnel joined to the face panel and having a yoke-mounting section, and an electron gun for emitting electron beams toward the phosphor screen. A deflection yoke mounted on the yoke-mounting section of the funnel has a first open end portion positioned on the side of the phosphor screen, and a correcting coil for correcting the positional deviation of the displayed image in a rotating direction is arranged at the first open end portion. The correcting coil is formed substantially rectangular to conform with the cross sectional shape of each of the yoke-mounting section and deflection coils of the deflection yoke.

Abstract: An electron gun for a color cathode ray tube including a triode consisting of a cathode, a control electrode and a screen electrode, and first and second focus electrodes facing each other and installed sequentially from the triode, for forming quadrupole lenses for focusing and accelerating an electron beam emitted from the triode, wherein three first-elongated electron beam passing holes slanting in one direction at a predetermined angle with respect to the longitudinal axis are formed on the facing surface of the first focus electrode, and three second-elongated electron beam passing holes slanting in a direction opposite to that of the first-elongated electron beam passing holes at a predetermined angle with respect to the longitudinal axis are formed on the facing surface of the second focus electrode, and wherein a dynamic focus voltage synchronized with a deflection signal is applied to the first focus electrode and a focus voltage is applied to the second focus electrode.

Abstract: A cathode ray tube includes a panel with an inner phosphor screen and a rear portion. A funnel is connected to the rear portion of the panel. The funnel is sequentially provided with a body having a large-sized end and a small-sized end, and a cone portion having a large-sized end and a small-sized end. The large-sized end of the body is sealed to the rear portion of the panel. The small-sized end of body meets the large-sized end of the cone portion at a point. A neck is sealed to the small-sized end of the cone portion. The funnel is structured to satisfy the following condition: 1.16≦(D/2)/tan((&psgr;/2))/(FG−TN)≦1.35 where D indicates the size of an effective area of the phosphor screen, FG indicates the distance between the large-sized end of the body and a final accelerating electrode of an electron gun fitted in the neck, TN indicates the distance between the small-sized end of the cone portion and the inflection point of the funnel, and &psgr; indicates an electron beam deflection angle.