Abstract: A lithography system includes an electron source, a lens, and a stencil mask. The electron source emits a beam of electrons. The lens converts the emitted beam of electrons into a diffuse beam of parallel electrons. The stencil mask is positioned between the lens and a semiconductor wafer with an electron-sensitive resists. The stencil mask has a pattern to selectively pass portions of the diffuse beam of parallel electrons onto the electron-sensitive resist of the wafer.

Abstract: The scanning electron microscope includes: an electron source; a first deflector for deflecting a primary electron beam emitted from the electron source; a second deflector for focusing the primary electron beam deflected by the first deflector and deflecting a second electron from a sample, which is generated the focused primary electron beam, to the outside of the optical axis; a voltage applying unit for applying a negative voltage to the sample to decelerate the primary electron beam; a spectrometer for dispersing the secondary electron; a detector for detecting the secondary electron passing through the spectrometer; an electrostatic lens provided between the second deflector and the spectrometer; and a voltage control unit that controls the voltage applied to the electrostatic lens based on the negative voltage applied to the sample. The electrostatic lens allows the deflecting action to be overlapped with the converging action.

Abstract: The present invention prevents electrostatic breakdown attributed to static electricity even in and after a cell cutting step. In a display device which includes a substrate, a plurality of pixels which is formed in a pixel part, a plurality of video lines which applies video voltages to the plurality of pixels, and a video voltage selection circuit which selects the video voltages to be inputted to the pixels and applies the selected video voltages to the predetermined video lines among the plurality of video lines, an electrostatic protective circuit for protecting a pixel part is connected to the plurality of video voltage inputting lines which inputs the video voltages to the video voltage selection circuit, and an electrostatic protective circuit for protecting a peripheral circuit is connected to the lines other than the video voltage inputting lines which is connected to the video voltage selection circuit.

Abstract: A high-frequency, high-voltage electron switch includes an electron source, a steering mechanism, a mask or anode plate, and a target. The electron source produces a beam of electrons with a voltage of at least about 1 kV that impinges upon the anode plate. The steering mechanism scans the electron beam across the anode plate at a scanning frequency of at least about 10 MHz. A hole or aperture is provided in the anode plate that allows the electron beam to pass through and produce a pulsed, high-voltage current in the target with a very high-frequency repetition rate and a very fast rise time. The pulsed, high-voltage current produced in the target can be used to cause a high-voltage source to turn on and off.

Abstract: A set of three cathodes, a control electrode, an accelerating electrode, a first focus electrode, a second focus electrode, a third focus electrode, a fourth focus electrode, a final accelerating electrode and a shield cup electrode are provided successively in an electron beam travelling direction. The shield cup electrode has a pair of screen-shaped electrodes that sandwich electron-beam through-holes in a vertical direction. A quadrupole lens that has a horizontal convergent action and a vertical divergent action is generated by an electrical potential difference between the screen-shaped electrodes and the final accelerating electrode. Accordingly, even if vertical and horizontal convergence power difference in a main lens formed by the fourth focus electrode and the final accelerating electrode is not large, a composite lens formed through a combination of the quadrupole lens and the main lens has strong horizontal convergence power and weak vertical convergence power.

Abstract: An electron gun is provided for a CRT. The electrode gun includes three cathodes for emitting electron beams, a plurality of acceleration electrodes, and a focus electrode and an anode. The focus electrode and the anode each include an opposite rim having a single electron beam pass-through hole with a vertical width V and a horizontal width H, and an electrostatic field control body positioned at a distance D from the rim, with a bridge width ‘t’, and a vertical width v and a horizontal width h of a central electron beam pass-through hole, wherein the electrostatic field control body and the focus electrode and the anode are configured to satisfy the following equation: (VxvxD)/29≧H−(2×S), where, S denotes a sum of the horizontal width h and the bridge width t of the electrostatic field control body. Spherical aberration is prevented or reduced, improving a vertical resolution of the picture.

Abstract: 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.

Abstract: Out of focusing electrodes which face each other in an opposed manner and constitute an electrostatic quadruple lens, one focusing electrode includes planar correction electrode plates which extend parallel to a tube axis while sandwiching electron beams from above and below. Here, the correction electrode plates include a reinforcing mechanism for suppressing the deformation or the displacement of the planar correction electrode plates. By suppressing the deformation and the displacement of the planar correction electrode plates which form the electrostatic quadruple lens, it is possible to provide a color cathode ray tube capable of exhibiting excellent focusing characteristics over an entire screen.

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 cathode ray tube (1) having an improved deflection unit (11) is described. The deflection unit (11) comprises line and/or frame coils that comprise a composition of wires having a conductive coating and wires having a non-conductive coating. Such deflection units have a good anti-ringing performance, while the good adhesion characteristics of non-conducting coated wires are maintained.

Abstract: A cathode ray tube includes an electron gun directing electrons towards a faceplate having an electrode biased at screen potential. The electron beam is magnetically deflected to scan across the faceplate to impinge upon phosphors thereon to produce light depicting an image or information. A neck electrode near the tube neck is biased at or below screen potential and a second electrode between the neck electrode and the faceplate is biased at or above screen potential. As a result, the electrons are deflected over a greater total angle than is obtained from the magnetic deflection. A third electrode proximate the faceplate is biased at or below screen potential to direct electrons towards the faceplate, thereby to increase the landing angle of the electrons thereon.

Abstract: A color display device comprising a cathode ray tube and a deflection unit. The display device includes magnets for correcting distortions in the raster displayed on the screen and means for providing correction currents through the coils of the correction magnets. The correction electromagnets are arranged substantially anti-mirror-symmetrically with respect to the field (vertical, y-z) deflection plane, substantially mirror-symmetrically with respect to the line (horizontal, x-z) deflection plane, and each correction coil extends along an arc portion between angles &agr;1 and &agr;2, said angles obeying the following rules: |cos(3&agr;1)−cos(3&agr;2)|≧1.33 and |cos(5&agr;1)−cos(5&agr;2)|≦0.5, &agr;1 and &agr;2 being taken with respect to the line (horizontal) deflection plane.

Abstract: The electron gun of a cathode ray tube comprises a main electron lens portion consisting of at least four electrodes arranged in the order of first grid (5), second grid (6), third grid (7) and fourth grid (8). An intermediate first voltage and an anode voltage are applied to the first grid (5) and the fourth grid (8), respectively. A resistor (100) is connected at one end to the second grid (6) and at the other end to the third grid (7) positioned adjacent to the second grid, with the result that second and third voltages of substantially the same potential, which are intermediate between the first voltage and the anode voltage, are applied to the second grid and the third grid, respectively. These grids are arranged such that a second electrostatic capacitance between the second and third grids (6, 7) is smaller than any of a first electrostatic capacitance between the first and second grids (5, 6) and a third electrostatic capacitance between the third and fourth grids (7, 8).

Abstract: An electrode of an electron gun, and an electron gun for a cathode ray tube are provided. The electron gun includes an outer-rim electrode having a large-diameter electron beam passing hole through which three electron beams pass, and an inner electrode installed inside the outer-rim electrode member, and having three electron beam passing holes disposed in an in-line arrangement and recesses formed at peripheries of the electron beam passing holes, the recesses having an eccentricity distance larger than an eccentricity distance between centers of the three electron beam passing holes.

Abstract: A cathode ray tube includes an electron gun directing electrons away from a faceplate having an electrode biased at screen potential. A plurality of electrodes located on or near the rear wall of the tube envelope are biased at graduated potentials so that the electron beam is deflected by the electrostatic field produced thereby to impinge upon the faceplate. The electron beam is magnetically deflected over a relatively small angle as it exits the electron gun to scan across the faceplate to impinge upon phosphors thereon to produce light depicting an image or information. The electrodes may be biased at or below screen potential, with the electrode closest the electron gun typically biased at a negative or ground potential and the electrode closest the faceplate (i.e. distal the electron gun) typically biased below screen potential to direct electrons towards the faceplate, thereby to increase the landing angle thereof.

Abstract: An inline electron gun includes three inline cathodes arranged in a same plane, a prefocus lens and a main focus lens which includes a plurality of electrodes for converging or diverging a thermion emitted by the cathodes to form electron beams. Focus lenses include a rim or a lip at opposite ends to form a large aperture. The main focus lens may include a focus electrode, an anode electrode and a subsidiary electrode arranged between the focus electrode and the anode electrode to define a beam course of respective red, green and blue electron beams. The focus electrode has symmetrical rectangular slots in its wall to define a green aperture of the subsidiary electrode, whereby the slots decrease influence of the electric field to the electron beam passing through the green aperture so that the red, green and blue spots on the screen have a uniform vertical diameter.

Abstract: An electron gun for a cathode ray tube includes a triode portion composed of three cathodes arranged in a horizontal line, and control and screen electrodes sequentially placed next to the cathode. First to fourth focusing electrodes are sequentially arranged one after another next to the screen electrode. The first focusing electrode has a first side facing the screen electrode and a second side facing a second focusing electrode. Three circular-shaped beam passage holes are formed in both sides of the first focusing electrode. The second focusing electrode has a first side facing the first focusing electrode and a second side facing the third focusing electrode. Three vertically elongated beam passage holes are formed in the first side facing the first focusing electrode and three circular-shaped beam passage holes are formed in the second side facing the third focusing electrode.

Abstract: 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.

Abstract: A cathode ray tube includes a deflection unit. A coil system of the deflection unit is provided with a conductive layer, the value for fmax/&Dgr;f ranging between 0.5 and 10, &Dgr;f being the half-value width of the impedance curve around a peak frequency fmax, and fmax being greater that 1 MHz. This results in a reduction of ringing phenomena.

Abstract: An electrode for electron guns of a color cathode ray tube includes an external rim electrode having a large electron beam-passing hole through which three electron beams pass; and first and second internal electrode pieces mounted in the large electron beam-passing hole, separated from each other and forming a central small electron beam-passing hole and two side small electron beam-passing holes wherein the central small electron beam-passing hole is defined by inner edges of the first and second internal electrode pieces, between the first and second internal electrode pieces, and the inner edges have the curvature of part of an ellipse having a major axis larger than the width of the large electron beam-passing hole.

Abstract: A color picture tube apparatus comprises auxiliary electrodes provided between first and second focusing electrodes, a nonaxisymmetric electrostatic lens is generated between the auxiliary electrodes and a focusing lens is generated between the first focusing electrode and the auxiliary electrode. A dynamic voltage V.sub.d is applied to the first and second focusing electrodes. Consequently, the effect of compensating the astigmatism of the electron beam caused by the deflection magnetic field and the defocus of the electron beam can be increased, the dynamic voltage can be decreased, and as a result, the cost of the circuit can be reduced. As the focusing function of the additional focusing lens is weakened and the electron beam trajectory is expanded, the magnification of the lens both at the center and the periphery of the screen can be equalized substantially and the uniformity of the focus of the electron beam between that at the center of the screen and that at the periphery of the screen becomes high.

Abstract: Focusing electrode in an electron gun for a color cathode ray tube, is disclosed, which can reduce a man-power and a number of components in a fabrication of the electron gun and can prevent a center electron beam from being elongated horizontally depending on a fitted depth of an inner guide electrode, the focusing electrode including a first focusing electrode adapted to be applied of a low static voltage and having a face with three vertically elongated electron beam pass-through holes of a key hole type and an inner guide electrode with three electron beam passthrough holes disposed at an inner side of the face, and a second focusing electrode adapted to be applied of a high dynamic voltage and having correcting electrodes unitary with a face of the second focusing electrode opposite to the first focusing electrode formed in a cathode direction at upper and lower sides of each of the three electron beam pass-through holes, whereby facilitating changes of center and side powers of the dynamic quadrupole le

Abstract: A cathode ray tube apparatus that can reduce the leakage extraneous electric field with low cost. The cathode ray tube apparatus comprises a front panel, a glass bulb having a funnel part including an anode terminal at the outer surface thereof and a neck part including an electron gun, a deflection apparatus comprising a horizontal deflection coil on the outer surface of the funnel part and the neck part of the glass bulb, a flyback transformer connected to the anode terminal of the funnel part via a first lead wire having an insulating coating, and a leakage extraneous electric field controller installed on the first lead wire. The controller reduces the leakage of the extraneous electric field from the first lead wire.

Abstract: A color cathode ray tube which has its resolution improved all over its screen covering the central portion and the peripheral portion, either by elongating or narrowing the plate length of plate electrodes (243), which are formed between a first kind of focusing electrode (241) and a second kind of focusing electrode (242) constituting together the electrostatic quadrupole lens of a halved focusing electrode (24) and which are connected with the second kind of focusing electrode (242) at the vertical portion (2430) of a passage for a central electron beam, or by making the shape of the central electron beam passing hole of an electrode (245) formed with the electron beam passing holes of the first kind of focusing electrode (241), longer than the shape of the beam passing holes for the side electron beams.

Abstract: An electron gun for a color cathode ray tube includes a triode having a cathode, a control electrode, and a screen electrode for producing electron beams; first, second, and third focus electrodes; and a final accelerating electrode sequentially disposed from the screen electrode. A first constant voltage is applied to the screen electrode and the second focus electrode, a second constant voltage higher than the first constant voltage is applied to the first focus electrode and the third focus electrode, and an anode voltage higher than the second constant voltage is applied to the final accelerating electrode, so that electron beams cross from the triode cross between a main lens formed by the third focus electrode and the final accelerating electrode, and an auxiliary lens formed by the first, second, and third focus electrodes. The electron gun produces uniform size electron beam spots over a fluorescent film of a cathode ray tube with reduced spherical aberration.

Abstract: Disclosed is a supplementary coil of a deflection yoke for a Braun tube. The supplementary coil forms a magnetic field of a pin-cushion type at a screen portion and a magnetic field of a barrel type at a neck portion at the same time. The deflection yoke includes a coil separator for fixing a relative position between horizontal deflection coils and vertical deflection coils by acting as an insulator. The supplementary coil also includes projections formed on inside surfaces of the neck portion and the screen portion of the coil separator. The supplementary coil is wound around the projections in the neck portion in a winding direction identical to a winding direction of the horizontal coil and wound around the projections in the screen portion in a winding direction opposite to the winding direction of the horizontal coil.

Abstract: An in-line electron gun includes main lens electrodes, a common aperture and, at a distance from the common aperture, three in-line apertures in a plate-shaped part. The outer apertures extend, viewed in a direction transverse to the plate-shaped part, beyond the common aperture.

Abstract: A display device with a DAF-gun (Dynamic Astigmatism and Focusing) in which the first focusing electrode (G3a) has at the side facing the pre-focusing part of the electron gun three elongated apertures (36, 37, 38). Hereby in operation in the vicinity of the elongated apertures an electron-optical field is generated between the pre-focusing part of the electron gun and the elongated apertures for reduction of the vertical dimension (vertical meaning transverse to the plane of the electron beams) of the beam size of the electron beams in the main lens. This reduction of the electron beam size results in an increase of the vertical dimension of the beam spot on the screen. This reduces Moire effects.

Abstract: A color cathode ray tube which has its resolution improved all over its screen covering the central portion and the peripheral portion, either by elongating or narrowing the plate length of plate electrodes 243, which are formed between a first kind of focusing electrode 241 and a second kind of focusing electrode 242 constituting together the electrostatic quadrupole lens of a halved focusing electrode 24 and which are connected with the second kind of focusing electrode 242, at the vertical portion 2430 of a passage for a central electron beam, or by making the shape of the central electron beam passing hole of an electrode 245 formed with the electron beam passing holes of the first kind focusing electrode 241, longer than the shape of the electron beam passing holes for the side electron beams.

Abstract: In a color cathode ray tube apparatus, a main electron lens unit for converging three in-line electron beams on a phosphor screen is formed of a plurality of electrodes, including at least first, second, and third electrodes, which are arranged from the cathode side toward the phosphor screen. An asymmetric electron lens, which horizontally diverges and vertically converges the electron beams, is formed on the cathode side in a lens effect region of a first electron lens composed of the second and third electrodes, and an asymmetric second electron lens, which has one effect with respect to the horizontal direction of the electron beams and another with respect to the vertical direction, is formed between the first and second electrodes, at the least.

Abstract: An electron gun of a color picture tube which can make uniform beam spots on a screen by eliminating astigmation of electron beams caused by a self-convergence yoke is constructed by the use of the improved shapes of vertical blades or horizontal blades of astigmation correction electrodes.

Abstract: An electron gun for a color cathode-ray tube, adapted for large television sets or high-definition monitors, has first and second quadrupole electrodes connected to a static voltage focus electrode and to a dynamic voltage focus electrode, respectively, to form a quadrupole lens. The first quadrupole electrode is composed of first electrode pieces connected to the static voltage focus electrode and arranged on left and right sides of three beam-passing apertures formed on the static voltage focus electrode, and each of the first electrode pieces has at least one arc having a radius identical to or larger than that of the beam-passing apertures. The second quadrupole electrode is composed of second electrode pieces connected to upper and lower portions of the dynamic voltage focus electrode, and each of the second electrode pieces has arcs having a radius identical or larger than that of the beam-passing apertures. The first electrode pieces are inserted inside of the second electrode pieces.

Abstract: An electron gun for a color cathode ray tube having sequentially formed a cathode, a control electrode, a screen electrode, a focus electrode and a final accelerating electrode, wherein the focus electrode is constituted by first and second focus electrodes. The first focus electrode includes an evenly formed electron beam inlet plane and an electron beam outlet plane in which a portion for shaping a central electron beam passing hole is formed convexly in respect to portions for shaping outer electron beam passing holes, while the second focus electrode comprises an evenly formed electron beam outlet plane and an electron beam inlet plane in which a portion for shaping a central electron beam passing hole is formed concavely in respect to portions for shaping outer electron beam passing holes. The quadruple lens formed between outer electron beam passing holes is formed asymmetrically, to improve the convergence characteristic.

Abstract: A one-gun three-beam electron gun comprises a triode part controlling an electron source generating a plurality of electron beams and emission of the electron beams generated by the electron source; a main electron lens of bi-potential focusing type consisting of not less than two cylindrical electrodes focusing the plurality of electron beams emitted by the triode part; electrostatic deflection plates disposed on the screen side of the main electron lens; and electrostatic deflection plates disposed on the electron source side of the main electron lens.

Abstract: A color cathode ray tube apparatus is provided with an electron gun assembly which emits three electron beams and focuses and converges the electron beam onto a phosphor screen. In the gun assembly, the electron beams generated from cathodes are accelerated and controlled by first and second grids and pass through third, fourth and fifth grids. The third and fourth grids have single rectangular apertures common to the three electron beams, respectively, which are faced to each other and have different heights and widths. Each of the fourth and fifth grids have individual apertures which allow the corresponding electron beams to pass therethrough, respectively. The third and fifth grids is maintained at fixed potentials and a potential of the fourth grid is adjusted. Thus, individual focusing and convergence electron lenses are formed between the fourth and fifth grids.

Abstract: An electron gun for a color cathode ray tube having a structure that a plate electrode to be provided within the focusing electrode is given the structure adding the external portion and providing in parallel three elliptical apertures in place of providing the cutout portion at the external portion, a plate electrode to be provided within the acceleration electrode is given the structure providing the cutout portion at the external portion and the vertical axis including the center of external elliptical portion is arranged outside the center axis when the side electron beam enters the main lens is capable of correcting astigmatism and satisfying static convergence. Moreover, rotation and deformation of plate electrode during assembling of electrode can be prevented by providing the straight line portion to the side beam apertures, aberration of lens to be generated at the main lens portion can be reduced and focus characteristic can also be stablized.

Abstract: A post-mask-deflection color cathode ray tube is disclosed that has a strip-type tension foil shadow mask in the form of two intercalated combs providing mutually insulated first and second arrays of strips. Each of the arrays is adapted to receive a different electrical potential effective to cause electron beams passing therethrough to be deflected by the electrical fields created between the strips. A method of manufacturing is also disclosed.

Abstract: A charged-particle beam tube having an envelope of a dielectric material and a pattern yoke formed on the inner surface of the envelope. The pattern yoke has a pair of horizonal deflection electrodes and a pair of vertical deflection electrodes arranged alternately. The horizontal deflection electrodes have a greater circumferential width than the vertical deflection electrodes. The horizontal and vertical deflection electrodes are supplied with different bias voltages.

Abstract: An electron feed structure for a flat-type luminous device capable of permitting electron emitted from an electrons source to be uniformly fed throughout a display section. The electron feed structure includes an electron flow guide constituted by an inner guide electrode of a high voltage and an outer guide electrode of a low voltage, so that an electric field of a high voltage and that of a low voltage may be alternately formed to form electrostatic lenses in the guide, to thereby effectively prevent the function of the electron flow guide from being deteriorated.

Abstract: An ion trap for an electron beam generator consists of at least two electrically conductive elements which are in the form of a sector of a cylinder the elements being spaced apart from each other and together form a cylindrical form. Each element has end plates and a number of fins extending inwardly to the center of the cylindrical form. A recess in the form of a sector of a circle is located in each end plate and each fin adjacent to the center of the cylindrical form. These recesses form a central bore through which an electron beam from an electron gun travels, the electron beam and central bore being essentially of the same diameter. Each elements is attached to an outer envelope by an insulating element and a conductive lead is electrically connected to each element to maintain that element at a predetermined potential which deflects positive ions travelling along the beam path.

Abstract: An aperture diaphragm for lithography apparatus which has a line-shaped multi-hole structure comprising blanking electrodes for generating a plurality of individually blankable particle beam probes for lithography apparatus comprising a particle beam source, a condenser lens, a blanking diaphragm and imaging optics and a workpiece to be structured such as a semiconductor body wherein a simple aperture diaphragm is composed of a high resistant substrate such as silicon or silicon dioxide upon which blanking electrodes are formed in the form of interconnects which are provided with terminals for applying blanking voltages.

Abstract: A parallel sweeping system for electrostatic sweeping ion implanters comprising an ion source for generating an ion beam, first and second multipole beam deflectors along and around a common optical axis and a target wafer to be raster-scanned by the deflected beam. The two deflectors have the same number of electrodes of five or more and have similar configurations. One electrode of the first deflector is paired with an electrode of the second deflector in the same plane common with the optical axis, but on the opposite side of the optical axis. The same sweeping voltage is applied simultaneously to each electrode of a pair in the same plane and predetermined different voltages to each pair of electrodes. Thus, a substrate is constantly raster-scanned by means of parallel ion beams with predetermined direction, namely raster-scanned with the ion beam all over a large wafer with exact parallelism to the optical axis.

Abstract: A cathode-ray tube in which outer convergence plates as constituents of the convergence plate assembly in the electron gun are supplied with individual voltages so that the horizontal misconvergence at the center portion and at the peripheral portions of the screen are positively corrected and in the arrangement the anode button is provided with a plurality of voltage supply pins. Further, the end portions of the two lead wires which are introduced form the anode button are opened outwardly so that the lead wires are prevented from coming in contact with the bead glass.

Abstract: An image display apparatus for displaying images on a fluorescent screen comprising plural linear cathodes, an electron beam extraction electrode with plural apertures and vertical deflection electrodes which are formed by segments. The respective segments of the vertical deflection electrodes have various shapes, and deflection voltages applied to the respective segments can be varied so that distortion of the displayed images on the fluorescent screen may be corrected.

Abstract: In an electromagnetic focusing electrostatic type image pick-up tube the electrostatic deflecting electrodes formed on the inner surface of the tube consist of 2 pairs of electrodes. Each of these electrostatic deflecting electrodes has a zig-zag shape from the electron gun towards the target. This zig-zag shape is twisted in the circumferential direction around the axis of the tube and variation rates of this twist amount are different, depending on the position in the axial direction.

Abstract: An electron beam device such as a cathode ray tube in which spherical aberration is reduced by optimising the axial potential distribution in the focusing lens of the electron gun. In one embodiment of the invention the electron gun comprises a beam forming part and a segmented focusing lens (25). The focusing lens (25) comprises a preformed glass tube (22) having a high-ohmic resistive layer (23) on the interior wall thereof, the resistive layer (23) comprises helical segments (33 to 37) alternated with intermediate segments (42 to 47). A focusing voltage is applied to the intermediate section (42) closest to the beam forming part and a higher voltage is applied to the end segment (47). The lengths of the helical segments (33 to 37) increase in a direction from the point of application of the focusing voltage whereas the lengths of the intermediate segments (42 to 46) decrease. The lengths of the helical segments (33 37) are such as to produce the desired axial potential distribution.

Abstract: A cathode-ray tube comprises an electron beam generating section provided at one end of the tube, a target provided at the other end of the tube, and a group of electrodes provided on an inner wall of the tube for focusing and deflecting an electron beam. The electrode group includes first and second electrodes between the one and other ends of the tube in the mentioned order. The first electrode has a lead electrode portion for supplying an electric potential to the second electrode. The lead electrode portion extends along the tube axis with a zigzag form in which an angle .angle.MZN of a convave apex M and a convex apex N adjacent thereto spanning in a circumferential direction centering the tube axis Z is not smaller than 115.degree. or a spiral form which rotates centering the tube axis at a rotation angle not smaller than 420.degree..

Abstract: An improved electron deflection system for a light valve of the type used in Schlieren dark field projectors is disclosed. The deflection system eliminates one set (D box 25) of three sets of deflection electrodes used in such projectors. This is accomplished by modifying the d.c. voltages and a.c. voltages applied to the deflection electrodes. A quadrupole d.c. voltage is added to the first control box set of electrodes (61, 62) and a second quadrupole voltage of opposite sense is added to the focus deflection box set of electrodes (63, 65). This modifies the vertical and horizontal beam angles differentially and the vertical and horizontal beam trajectories differentially in a manner to compensate for the composite effects of spherical aberrations, deflection focusing aberrations, and the static starfish lens generated by the interaction of the square box electrode structure against the round drift ring assembly (21) of the deflection system.

Abstract: A generally box-shaped electron lens system for use in an oscilloscopic or storage cathode-ray tube for the amplification of both vertical and horizontal deflections of the electron beam from the gun to the target of the CRT. The lens system comprises two electrodes at least partly displaced from each other along the CRT tube axis, with a gap therebetween for electrically insulating one from the other. A pair of tongues extend either from the gun-side electrode into the target-side electrode, or from the target-side electrode into the gun-side electrode, or two such pairs of tongues extend from both electrodes into interdigitating relation to each other. Upon application of prescribed potentials to the two electrodes, a quadrupolar lens field is created in the space between the pair or pairs of tongues for deflection amplification in both directions. On having been deflected vertically, the beam has its deflection amplified by having its traveling direction inverted with respect to the tube axis.

Abstract: An electrostatic decelerating and scan expansion lens system (10) includes a mesh element (56) and operates in a cathode-ray tube (12) that incorporates a microchannel plate (24). The lens system is positioned downstream of the deflection structure (42 and 44) and provides linear magnification of the electron beam deflection angle. The mesh element is formed in the shape of a convex surface as viewed in the direction of travel of the electron beam (40) to provide a field with equipotential surfaces (100) of decreasing potential in the direction of electron beam travel. Secondary emission electrons generated by the mesh element as it intercepts the electron beam, are therefore, directed back toward the lens system and not toward the microchannel plate. Only the beam electrons strike the microchannel plate, which provides on the phosphorescent display (20) an image of high brightness, free from spurious light patterns.