Abstract: A color display tube (1) is disclosed with an improved suspension of the color selection electrode (12). In order to have a color display tube (1) with good properties of, for instance, color purity, it is of eminent importance that the positional stability of the color selection electrode (12) is excellent. Especially wide-screen tubes seem to be more sensitive to shocks by which the color selection electrode (12) may shift and cause discolorations. The positional stability of the color selection electrode (12) can be improved by increasing the stiffness of the corner sections (16) of the color selection electrode (12). This can be realized by introducing an additional support plate (41) in the corner section (16). Also the optimization of the position of the supporting element (17) with respect to this corner section (16) yields an improvement.

Abstract: In a shadow mask type color cathode-ray tube having slot apertures that are straight in the perpendicular direction, the projections of electron beams transmitted by the slot apertures onto the fluorescent screen tend to curve in a banana-like shape with increasing proximity to the right and left sides of the screen, thereby bringing about a drop in the color interference margin and loss margin. The projection of electron beams that are transmitted by the slot apertures and strike the fluorescent screen can be made straight by boring slot apertures in advance that are curved in the direction opposite the curvature of the electron beam projection.

Abstract: A shadow mask includes an aperture portion having a plurality of apertures formed therein, the aperture portion being formed over a predetermined area in a center of the shadow mask; and a non-aperture portion defining a periphery of the shadow mask and formed adjacent to the aperture portion. Only the aperture portion is selectively heat-treated to result in a tensile strength of the aperture portion being 1.2 to 3 times greater than that of the non-aperture portion, and the modulus of elasticity of the aperture portion being 1.5 to 3 times greater than that of the non-aperture portion. The method includes the steps of selectively performing a heat-treating process on only the aperture portion of the shadow mask by mounting a separating cover on the non-aperture portion, the separating cover preventing contact of the non-aperture portion with the gaseous atmosphere present during the heat treating process. The shadow mask is then press-formed.

Abstract: 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.

Abstract: An inner shield for a cathode ray tube comprising a plurality of rectangular segments parallel to the tube axis; a flange joined to each of the rectangular segments and bent in a right angle for mounting on a mask frame; a trapezoid portion joined to each of the rectangular segments, being arranged slantwise along an inner circumference of a funnel; and a pair of holes formed in the two adjacent trapezoid portions to decrease a deflection in a East-West direction of an electron beams. Since an undesirable affection on the electron beams caused by the earth magnetic field is decreased, a pin-cushion distortion and barrel distortion of the electron beams are highly decreased.

Abstract: In a color cathode ray tube in which a shadow mask and an inner magnetic shield are supported by a mask frame and an electron shield is provided in the mask frame, at least a part of the electron shield is made to have a smaller anhysteretic magnetic permeability than the shadow mask, the mask frame and the inner magnetic shield when an applied magnetic field is 800 A/m (10 Oe). Since the magnetic resistance of the electron shield increases, it is possible to reduce a leakage magnetic field from a tube-axis-side edge of the electron shield. Thus, a color cathode ray tube that reduces mis-landing due to a terrestrial magnetism and has no color displacement can be provided.

Abstract: The color display tube (1) has a display window (3) and a curved shadow mask (13). The inner surface (15) of the display window (3) may be substantially flat or it may be curved with a curvature smaller than the curvature of the shadow mask (13). The distance Qp from the shadow mask (13) to the screen (6) at the inner surface (15) of the display window (3) of the color display tube (1) according to the invention is larger by a positive integer, not being a multiple of three, for all positions p on the screen (6) than this distance Q0p in prior art tubes.

Abstract: A color cathode ray tube comprising a perforated molded mask curved inward in the middle between its two opposite sides and having round corners, and a support frame curved outward in the middle between its two opposite sides and having round corners, wherein the corners of mask are respectively brought into contact with the corners of the mask and the frame. Therefore, the alignment accuracy between a shadow mask assembly and phosphor film and the magnetic shielding of the color cathode ray tube can be improved.

Abstract: A color display device comprises an electron gun, a display screen with a curved inner surface and a flat color selection electrode as well as a deflection means. The distance between the electron beams is dynamically varied, whereby the distance in the deflection space increases as the beams are deflected in at least one direction. The reduction of the distance enables the distance between the color selection electrode and the display screen to be decreased in that direction. As a result, the curvature of the inner surface of the display window is increased, which has a positive effect on the strength and weight of the display window.

Abstract: A color cathode ray tube is provided with a shadow mask structure which includes a shadow mask formed by integrally forming an apertured portion, an imperforate portion and a skirt portion, and a support frame having a frame portion into which the skirt portion is fitted. The skirt portion of the shadow mask has respective long sides and respective short sides thereof recessed inwardly, and the frame portion has respective long sides and respective short sides formed in planes having no welding bosses, and the skirt portion is fitted into and welded to the frame portion. Furthermore, an end of the outside of the skirt portion and the inner wall of the frame portion have respective entire peripheries thereof come into contact with each other. With such a construction, the shadow mask structure has a small magnetic resistance and the shadow mask is prevented from being vibrated at the time an external vibration is applied to the cathode ray tube.

Abstract: Structure for fastening a flat Braun tube to a cabinet, which can prevent damage to a panel and reduce assembly working-hours, including a holding member for fastening to a portion of an outer circumference of the panel, and a lug fitted to the holding member for fastening to the cabinet.

Abstract: The CRT has a tensioned shadow mask with between 160-180 or between 210 and 240 slits per row and display devices having such CRT's. The first embodiment is in particular suited for CRT''s having a screen size larger than 21″ and for TVT applications, giving a substantially Moire free image for an NTSC, PAL and VGA signal, the second embodiment is in particular suited for CRT's having a screen size of 23″ or smaller and for CMT applications, giving a substantially Moire free image for a SVGA and XGA signal.

Abstract: A flat cathode ray tube is provided. The flat cathode ray tube includes a shadow mask having a plurality of electron beam holes, a shadow mask frame having multiple-layered support members continuously connected, for supporting the shadow mask, and an inner shield connected to the shadow mask frame. The support member for supporting a shadow mask is solidified by forming multiple-layer laminates. Also, mobility is provided to the longer sides of the shadow mask, thereby easily applying a tension to the shadow mask.

Abstract: A color cathode ray tube is provided with a shadow mask having a mask body including a substantially rectangular effective surface in which a large number of electron beam passage apertures are formed.

Abstract: 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.

Abstract: A shadow mask spring for a color cathode ray tube having a generally rectangular shadow mask structure including a shadow mask and a support frame for holding the shadow mask. Shadow mask springs serve for holding the support frame inside a panel having a phosphor screen adjacent thereto and engage with panel pins for holding the shadow mask structure. Each of the shadow mask springs includes L-shaped base plate and a joined plate secured to one end of the base plate. The base plate has a phosphor screen side metal portion and an electron gun side metal portion with the phosphor screen side metal portion having a smaller thermal expansion coefficient than that of the electron gun side metal portion. An other end of the base plate is secured to a side of the support frame.

Abstract: A color selecting apparatus for a cathode-ray tube including a frame, and a mask supported in the frame with tension along a minor axis, where the mask having a rectangular hole part formed with a plurality of electron beam-passing apertures, a non-hole part surrounding the hole part, and a pair of vibration attenuating members attached at both ends of the surface of the non-hole part, facing each other along a major axis, for attenuating vibration waves which transmit along the major axis. The vibration attenuating members are made of a metal having a greater mass than the non-hole part, and attached by spot-welding so that they are away from the non-hole part by a predetermined gap at every portion except the welding points. Therefore, the vibration attenuating members serve as a damper to attenuate vibrations which transmit in the major direction, particularly vibrations generated by the speakers.

Abstract: To realize a high-quality flat-face type of color cathode ray tube by combining a tint panel with a pressed mask, the outer surface of the panel of the color cathode ray tube is made nearly flat and the inner surface of the panel is curved in a concave shape, and the long-length direction pitch of slots formed in an aperture region 2 of a pressed mask 1 to be disposed close to the inner surface and the connection-direction width of each of bridges which connect the slots are made different between a central portion (A) and a peripheral portion (B) in the apertured region 2 of the pressed mask 1, whereby the ratio of bridges per unit area is made larger in the central portion (A) than in the peripheral portion (B) or the opening rate of slots per unit area is made larger in the peripheral portion (B) than in the central portion (A).

Abstract: A holder 30 supporting a mask frame 13 is formed by bending an elongated, substantially rectangular metal plate in opposite directions along first and second bending lines 33a and 33b, such that the holder has an engagement portion 35 engaged with a corresponding stud pin, a fixed portion 34, and a slope portion 36 extending and inclined between the engagement portion and the fixed portion. When the mask frame has thermally expanded, the holder moves the mask frame toward a phosphor screen along the center axis of a face panel. The fixed portion 34 has a projection 40 projecting from the vicinity of an acute-angle portion 50 which is defined by a side edge of the fixed portion and the first bending line. The fixed portion is fixed to the mask frame in the vicinity of the first bending line by welding at least a part of the projection to the mask frame.

Abstract: A color cathode ray tube has a vacuum enclosure including a panel unit having a fluorescent film formed on an inner face, the fluorescent film consisting of densely arrayed three color dot trios of a fluorescent material. A shadow mask is mounted in the vicinity of the fluorescent film. The color cathode ray tube further includes a neck unit housing an electron gun for emitting three electron beams and a funnel unit for joining the panel unit and the neck unit. The panel unit has a diagonal diameter of not more than 52 cm and an effective display area on an outer face of the panel unit has a diagonal radius of curvature of not less than 1,300 mm. The dot trios of the fluorescent material are horizontally arrayed in a number of approximately at least 1600, and a cover film is applied to the panel unit to lower optical transmittance.

Abstract: In a color cathode ray tube, a shadow mask has a shadow mask thin plate that includes Fe—Ni. The shadow mask thin plate has a volume ratio, FR of &ggr;-FIBER to a crystal face having {100}<001> cube orientation between 0.5 and 5.0.

Abstract: Shadow mask in a cathode ray tube including an effective surface, and a non-effective surface, wherein the effective surface includes elongated slots each extended in full length of the effective surface without bridges between slots in a vertical direction at left and right outermost sides of the shadow mask or outer side slots adjacent to the outermost side slots, thereby preventing wrinkles from being formed at sides of an effective surface to enhance a color purity of the picture.

Abstract: The present invention relates to a support frame for a cathode-ray tube which is capable of preventing damage of a corner portion of a support frame circumference in forming of the support frame. The support frame for supporting a shadow mask of a cathode-ray tube in accordance with the present invention comprises notches formed on a certain portion of an upper surface of the corner portion of the support frame circumference, in more detail on the longer side and shorter side of the support frame circumference.

Abstract: A cathode ray tube capable of preventing incorrect hitting of color electron beams caused by the local doming phenomenon and the initial doming phenomenon from occurring and thus preventing displacement of colors, unevenness in colors, and deterioration of luminance from occurring is provided. The cathode ray tube includes a shadow mask made of a flat plate in which a number of apertures 2 are arranged in lines, and slits 5, 6 are formed in the line direction of the apertures 2. These slits 5, 6 have inclined faces 8, 9, 11 and 12 opposed via openings 10, 13. Due to this configuration, the displacement of apertures due to the local doming phenomenon or the initial doming phenomenon caused by the thermal expansion of the shadow mask can be suppressed. Thus, displacement of colors, unevenness in colors, and deterioration of luminance caused by incorrect hitting of electron beams can be prevented from occurring.

Abstract: A color cathode ray tube comprises a vacuum envelope in which there is mounted a shadow mask having a curved surface having a plurality of electron beam passing holes and a skirt extending downward from the margin of the curved surface. The shadow mask is supported by a mask frame having a substantially rectangular side wall. A shadow mask assembly constituted by fitting and securing the skirt into the side wall is set in the panel of the envelope, and the skirt is fitted and secured into the side wall by curving the middles of two or four facing sides of the skirt inward. Thereby, it is possible to provide a color cathode ray tube having the shadow mask assembly capable of obtaining a superior magnetic shielding characteristic by enlarging the effective region of the curved surface of the shadow mask.

Abstract: Structure for supporting a shadow mask in a color cathode ray tube including main frames each extended along a long side having the shadow mask welded thereto directly, subframes each extended along a short side connected to the main frames for supporting the main frame, plate type supporting members each fitted to a position of an outer surface of respective frames, and elastic members having one side coupled to a stud pin on an inside surface of the panel, and the other side fitted to the supporting member, wherein the supporting member of the subframe includes a first and a second flanges opposite to each other extended downward vertically, and a parallel part extended horizontally between the first and second flanges, thereby maintaining a uniformity of welding quality during cathode ray tube fabrication and preventing color distortion during operation of the cathode ray tube.

Abstract: A tension mask frame assembly for a color cathode-ray tube includes a frame including first and second support members, and at least a pair of elastic members supporting the first and second support members, both end portions of each of the elastic members are secured to the first and second support members, a tension mask including a plurality of strips and forming slits, a plurality of tie bars disposed between the strips and connecting neighboring strips to divide slits, where longer side portions perpendicular to a lengthwise direction of the strips are secured to the first and second support members, and vibration prevention members having both end portions supported at the first and second support members, having a predetermined tensile force, and being in contact with shorter side portions of the tension mask in a direction parallel to the strips of the tension mask.

Abstract: The present invention provides an improvement in a color picture tube having a tension mask supported by a support frame mounted within the tube. The mask includes an active apertured portion formed by a plurality of parallel vertically extending strands, between which are elongated operational apertures through which electron beams pass during operation of the tube. Top and bottom border portions, outside the active apertured portion of the mask, have additional apertures therein that are aligned with the longitudinal centerlines of the strands.

Abstract: 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.

Abstract: A color cathode ray tube including a shadow mask assembly and an inner shield provided for the shadow mask assembly which are disposed within the tube. The shadow mask assembly includes a substantially rectangular shadow mask, a substantially rectangular mask frame, and a spring for mounting the shadow mask assembly in the panel of the cathode ray tube. The shadow mask has a curved surface having electron beam passing holes and a skirt folded from the margin of the curved surface and extending in a tube axis direction. At least one of the major and minor sides of the substantially rectangular shadow mask has a curvature convex to the tube axis with corners thereof being round and at least one of the major and minor sides of the substantially rectangular mask frame is linear or has a curvature concave to the tube axis with corners thereof being round.

Abstract: A shadow mask structure to which this invention is applicable comprises a mask frame and a shadow mask. The mask frame is provided with a frame plate and a pair of major sidewalls perpendicularly risen from a pair of major sides of the frame plate. The shadow mask is spanned between top edges of the major sidewalls so as to be tensioned. The shadow mask has an aperture area and a no-aperture area. The no-aperture area is extended on a peripheral region. The shadow mask has a pair of half-etched dent areas formed on the no-aperture area along the pair of minor sides of the shadow mask. The half-etched dent areas have a large number dents.

Abstract: A color selecting electrode of a cathode ray tube is prevented from being twisted to thereby suppress an electron beam from a mislanding. A metal thin plate (6) having vertically striped opening portions (6a) is supported by frame members (7a), (7b) under a proper tension. The frame member (7a) welded to the metal thin plate (6) is joined with a supporting member (8) extended in the longitudinal direction and the frame member (7b) welded to the frame member (7a) is joined with a supporting member (9) extended in the direction (Z-axis direction) perpendicular to a plane formed of the frame members (7a, 7b). The supporting member (9) is fixed to substantially a central portion of the frame member (7b).

Abstract: An inner surface of an effective portion (10) of a substantially rectangular panel is formed to be a curved surface which satisfies relationships of RyP1<PyP0, RyP1<RyPH, RyP1<½·RyP2 and RyP2<3·RyP1, where RyP0 is a radius of curvature of the inner surface in a short axis direction thereof at the center of the effective portion (10), RyPH is a radius of curvature of the inner surface in the short axis direction at an end of a long axis of the effective portion (10), RyP1 is a radius of curvature of the inner surface in the short axis direction at a position within a range of {fraction (7/16)}·WPH to ¼·WPH from the center of the effective portion in the long axis direction, wherein WMH is a width of the effective surface in a long axis direction thereof, and RyP2 is a radius of curvature of the inner surface in the short axis direction at an end of the effective portion on a line parallel to the short axis passing through the position on the long axis withi

Abstract: A substantially rectangular shadow mask is arranged opposite to a phosphor screen formed on an inner surface of a panel. The shadow mask has a mask body and a mask frame to which a peripheral portion of the mask body is attached. The shadow mask has a rectangular form having a center through which a tube axis passes, and a long axis and a short axis passing through the center and perpendicular to each other. The mask frame has a pair of long side walls extending parallel to the long axis and a pair of short side walls extending parallel to the short axis. The height of each long side wall at a central portion along the tube axis is lower than the height of each short side wall at a central portion along the tube axis.

Abstract: A shadow mask assembly includes a mask frame and a shadow mask supported by the mask frame for extension. The mask frame is of a rectangular shape having a pair of longer side members and a pair of shorter side members. Both the edges of the shadow mask is bonded onto the longer side members while the shorter side members are bent by an external force within the elasticity thereof. After the external force is removed, the shorter side members are slightly deformed within the elasticity thereof whereas the deformation of the longer side members is substantially removed. Suitable tension can be applied to the shadow mask in a wider temperature range.

Abstract: Resistance to deformation of a support spring for the mask-frame assembly of a cathode ray tube is improved by adding strengthening ribs running longitudinally along the edges of the body and partially into the base of the spring.

Abstract: A cathode ray tube capable of reducing the doming amount and suppressing the occurrence of moire stripes at the same time, which also can prevent the so-called persimmon stone phenomenon from occurring, is provided. In the apertures, the protruding portions that are protruding from end faces in the horizontal direction of the apertures to the inside of the apertures are formed. The protruding portion in the aperture located on the right side of the phosphor surface from the vertical center line of the shadow mask is protruding in the direction toward the peripheral portion on the right side, while the protruding portion in the aperture located on the left side of the phosphor surface is protruding toward the peripheral portion on the left side.

Abstract: A cathode ray tube capable of reducing the shifting of apertures in the horizontal direction of the screen during the operation of the cathode ray tube, thereby preventing a color displacement, unevenness in colors, and reduction in luminance from occurring. By taking a center line of a shadow mask in a horizontal direction as an X-axis and a center line of the shadow mask in a vertical direction as a Y-axis, bridges in the vicinity of both ends of a perforated portion in the X-axis direction have a greater arrangement pitch in the vertical direction than that of bridges in the vicinity of a Y-axis.

Abstract: Color cathode ray tube including a panel in front portion of the cathode ray tube, and a shadow mask spaced from, and fitted to rear of the panel for selecting a color from electron beams, wherein at least one of an inside surface of the panel and the shadow mask have a curvature structure in which a radius of curvature varies continuously within a fixed ratio range, thereby enhancing a strength and improving howling.

Abstract: A color CRT suppresses deformation of the main shadow mask surface after fastening the shadow mask to the mask frame. Numerous substantially rectangular grooves or substantially circular recesses are formed in the damper part disposed to the shadow mask skirt so that the bending strength in the circumference direction of the skirt is greater than the bending strength in the direction parallel to the tube axis.

Abstract: Mask in a color cathode ray tube, including electron beam pass through holes with bridges connected to non-hole portions between the beam pass through holes in a width direction, wherein a thickness of the bridge of the mask facing an electron gun is formed thinner than other portions of the mask, thereby attenuating howling and enhancing a luminance.

Abstract: A stretched mask having a high tensile strength and favorable high-temperature creep properties and free from tape twist, and a material for the stretched mask. A low-carbon steel sheet containing 70 ppm to 170 ppm of nitrogen on a weight basis is heat-treated at a temperature at which recrystallization does not take place. The heat-treated material is provided with a resist pattern for forming apertures and subjected to etching to form apertures.

Abstract: A color cathode ray tube includes an evacuated envelope having a panel portion, a neck portion, and a funnel portion for connecting the panel portion and the neck portion, 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 peripheral skirt portion, a generally rectangular support frame for suspending the shadow mask by spot welding the peripheral skirt portion thereto, within said panel portion, a phosphor screen formed on an inner surface of the panel portion, an electron gun housed in the neck portion, and a deflection yoke.

Abstract: A method of manufacturing a color thin film electroluminescent display apparatus includes steps of: forming anodes consisting of an ITO on a transparent support substrate; forming a hole transporting layer thereon; carrying the substrate on a substrate holder within a vacuum evaporation device; placing a shadow mask, in which a side surface of opening sections has a taper, between the substrate and first, second and third resistance heat boats; evaporating a green electroluminescent material by means of the first heat boat and forming a green luminous layer on the substrate; evaporating a blue electroluminescent material by means of the second heat boat and forming a blue luminous layer on the substrate; successively, evaporating a red electroluminescent material by means of the third heat boat and forming a red luminous layer on the substrate; and thereafter, forming cathodes on the luminous layers.

Abstract: 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.

Abstract: Disclosed is a shadow mask for a cathode ray tube (CRT) and a method of manufacturing the same. The shadow mask includes a solid solution hardening material and a precipitation hardening material. The method includes the steps of heat treating a metallic plate having a plurality of apertures formed therein using a carburizing gas, and press-forming the metallic plate into a shadow mask shape.

Abstract: A shadow mask frame assembly of a flat cathode ray tube (CRT) includes a shadow mask including a plurality of strips formed at a main body in a vertical direction by being separated a predetermined distance by slits and a plurality of bridges forming slots by connecting neighboring strips and sectioning the slits, in which the slots include a first slot group including slots having a wide interval between the bridges and a second slot group including slots having a narrow interval between the bridges, first and second support members secured at a long side portion of the shadow mask, and a frame including first and second elastic members, either end portion of each of which is secured to each of the first and second support members, for applying a tension force to the shadow mask.

Abstract: A cathode ray tube face panel having an upstanding wall therearound with a plurality of article supporting studs retained therein, said studs being formed from an alloy having a chromium content of from about 10 to 16% by weight and the balance iron.

Abstract: A cathode ray tube has a panel portion 1 with a phosphor layer 5 formed on its inner face, a neck portion 2 accommodating an electron gun 9, a funnel portion 2 for coupling the panel portion 1 to the neck portion 2 and a color selective electrode assembly 6 having a number of electron beam passing openings arranged opposite to the phosphor layer 5 with a space therebetween. The color selective electrode assembly is installed within the panel portion 1. An electron beam reflection film of a bismuth oxide thin film 6R having a bulk density of at least from 41 g/cm3, to 9.3 g/cm3, e.g., is formed on the face of the color selective electrode assembly 6 against which the electron beams 14 emitted from the electron gun 9 collide. The cathode ray tube is capable of displaying high density and high resolution image.

Abstract: An improved color picture tube (10) has a shadow mask (24) mounted therein in spaced relation to a viewing screen (22) thereof. The mask has a rectangular periphery with two long sides and two short sides. A major axis (X) passes through the center of the mask and parallels the long sides thereof, and a minor axis (Y) passes through the center of the mask and parallels the short sides thereof. The mask has an aperture array (35) that includes slit-shaped apertures (36) aligned in columns (37) that essentially parallel the minor axis and end at a border of the aperture array. The improvement comprises the column-to-column spacing (aH) parallel to the major axis including a pseudo-cyclic variation at least in a portion of the mask, wherein a complete cycle within the pseudo-cyclic variation occurs in the column-to-column spacings between no more than nine consecutive columns.