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.

Abstract: A color picture tube has a tensioned mask supported by a support frame mounted within the tube. The mask has a significantly lower coefficient of thermal expansion than the frame. The mask has an active apertured portion formed by a plurality of parallel vertically extending strands, through which electron beams pass during operation of the tube, and two opposite side border portions outside the active apertured portion. The two opposite side border portions have tie bars that extend between the vertical strands of the mask. The tie bars accommodate expansion of the frame, while substantially maintaining the positions of the vertical strands in the active portion of the mask.

Abstract: We are familiar with etching printed circuit boards chemically by providing a copper board with a mask and etching copper away chemically at those points where the mask is not present. This is disadvantageous, e.g. from environmental standpoints, because the chemical liquid is increasingly enriched with copper, and, when the liquid has been used, it can no longer be employed and is also difficult to dispose of. The invention is based on the object of providing a method of either applying or removing conductive material electrically.

Abstract: A method for developing an electrostatic latent charge image formed on a photoreceptor 36 which is disposed on an interior surface of a faceplate panel 12 of a CRT 10 utilizes a developer 40 having a developing chamber 42 with a sidewall 50 closed by a bottom end 44 and a panel support 46 at the other end. An opening 48 is formed through the panel support 46 to provide access to and support for the faceplate panel 12. A panel grid 74 is disposed in proximity to said interior surface of said faceplate panel 12 and operated at a first potential to control the electric field from the latent charge image. A tank grid 56 is disposed within said developer 40 and spaced from the sidewall 50, the bottom 44 and the panel grid 74. A triboelectric gun 84 is disposed within the developer 40 for imparting a desired charge polarity to the screen structure material and for distributing the charged screen structure material onto the latent charge image.

Abstract: A cathode-ray tube has an internal magnetic shield and at least one contact spring attached to the shield. The shield includes a land with an outer edge and an inner edge. The spring includes two portions, an improved clasp portion attached to the shield at the land, and a contact leaf portion. The improved clasp portion includes a flat body with a reverse bend hook at a first end, and a latch and a catch at an end opposite to the first end. The hook engages the outer edge of the land, and the latch engages the inner edge of the land. The catch includes a bent end portion that forms an acute angle with the remainder of the catch. The bent end portion is positioned to engage the inner edge of the land if the spring is rotated about the hook. The leaf portion is connected to and extends from the latch.

Abstract: A color picture tube comprises an evacuated envelope having an electron gun therein for generating at least one electron beam, a faceplate panel having a luminescent screen with phosphor lines on an interior surface thereof, and a tension focus mask. The mask has spaced apart first metal strands which are adjacent to an effective picture area of the screen and define a plurality of slots substantially parallel to the phosphor lines. Each of the first metal strands across the effective picture area have a substantially continuous insulator layer on a screen-facing side thereof. The mask also includes a plurality of second metal strands oriented substantially perpendicular to the first metal strands. The second metal strands are spaced from the insulator layer when the tube is not energized and are in contact with the insulator layer when the tube is energized.

Abstract: A cathode-ray tube has an internal magnetic shield and at least one contact spring attached to the shield. The shield includes a land with an outer edge and an inner edge. The spring includes two portions, a clasp portion attached to the shield at the land, and a contact leaf portion. The clasp portion includes a flat body with a reverse bend hook at a first end, and a latch at an end opposite to the first end. The hook engages the outer edge of the land, and the latch engages the inner edge of the land. The leaf portion is connected to and extends from the latch.

Abstract: The present invention provides an improvement in the mounting of a cathode-ray tube within a cabinet. The cathode-ray tube includes a glass envelope having a faceplate panel, a funnel and a neck. The panel includes a faceplate that is surrounded by a peripheral sidewall. A tension band encircles the outer periphery of the sidewall. The cabinet has resilient extensions from the interior thereof, that engage a portion of the tension band and support the tube within the cabinet.

Abstract: An improved color picture tube has a tensioned mask and support frame assembly. Each of the mask and the support frame is rectangular and has two long sides that parallel a central major axis thereof and two short sides that parallel a central minor axis thereof. The improvement comprises the frame including two first members, paralleling the major axis, and two second members, attached to the ends of said first members, paralleling the minor axis. Each of the second members includes a pinched section that elongates it.

Abstract: An improved inline electron gun includes a plurality of electrodes spaced from three cathodes in the direction of a longitudinal axis of the gun. The electrodes form at least a beam forming region and a main focus lens in the paths of three electron beams, a center beam and two side beams. Each of the electrodes includes three inline apertures therein for passage of the three electron beams. The beam forming region includes the cathodes and three consecutive electrodes, a G1 electrode, a G2 electrode and a G3 electrode. The improvement comprises the G2 electrode having two linear projections on either side of the inline apertures therein. The projections parallel the inline direction of the apertures protrude in a direction parallel to the longitudinal axis, past the apertured portion of the G3 electrode in overlapping relationship therewith. On the side of the G3 electrode facing the G2 electrode, the G3 electrode has two linear channels therein on either side of the inline apertures therein.

Abstract: A light-absorbing matrix 23, having openings therein, is formed on an interior surface of a faceplate panel 12 of a cathode-ray tube 10 by providing a photoreceptor thereon, electrostatically charging the photoreceptor 72 to a substantially uniform level of charge, and exposing the photoreceptor to light through openings 33 in a color selection electrode 24 to selectively discharge the more intensely illuminated areas of the photoreceptor, without substantially discharging the less intensely illuminated areas. The photoreceptor 72 comprises a plurality of layers including a photoresist layer 56, a conductive layer 62, and a photoconductive layer 66. The openings 33 in the color selection electrode 24 have a dimension substantially greater than the dimension of the openings in the resultant matrix 23.The photoreceptor 72 is contacted with a liquid toner having charged pigment particles which form toner lines 84 on the less intensely illuminated areas of the photoreceptor.

Abstract: The present invention relates to a backlight system for transmissive electro-optical modulator comprising: at least one source of light rays; at least one reflector for returning the light rays along a first direction referenced z; a means of transmission of light, positioned at the exit of the reflector in such a way as to transport the light rays along the z direction, one of the faces of the transmission means lying along the z direction comprising a micro-prismatic structure which specularly reflects the light rays and extracts them from the transmission means substantially along a second direction referenced x perpendicular to the first direction and a collimation means (20) situated between the source of light rays and the transmission meansz. The said collimation means (20) comprises an entrance face (21) inclined with respect to the first direction referenced z. The invention applies more particularly to retroprojection.

Abstract: The invention relates to a method of manufacturing a luminescent screen structure 22 with a light-absorbing matrix 23, having a plurality of substantially equally sized openings therein, on an inner surface of a CRT faceplate panel 12. A color selection electrode 24 is spaced a distance, Q, from the inner surface. The method includes providing a first photoresist layer 50, whose solubility is altered when it is exposed to light, on the inner surface of the faceplate panel 12. The first photoresist layer 50 is exposed to light from two symmetrically located source positions +G and -G, relative to a central source position, 0. Then the more soluble regions 54 of the photoresist layer 50 are removed, overcoated with a light-absorbing material 58 and developed to remove the retained, less soluble regions 52 of the first photoresist layer with the light-absorbing material thereon. First guardbands 60 of light-absorbing material remain on the interior surface of the faceplate panel 12.

Abstract: An improved color picture tube includes a glass envelope comprising a faceplate panel, a funnel and a neck. The faceplate panel has four sides and four corners and includes a transparent rectangular faceplate, having a cathodoluminescent screen on an interior surface thereof, and a sidewall peripherally extending from the faceplate. The end of the sidewall facing the funnel has a seal land that is sealed to the funnel. The improvement comprises the sidewall seal land having a varied width around the periphery of the panel, wherein the widest portions of the sidewall seal land are located along the panel sides and the narrowest portions of the sidewall seal land are located at the corners of the panel. The width of the sidewall seal land is from 5% to 17% less in the corners of the panel than at the centers of the sides of the panel.

Abstract: The invention includes an apparatus 40, 140 for developing a latent charge image formed on a photoreceptor 36 disposed on an interior surface of a faceplate panel 12. The apparatus 40, 140 comprises a developer tank 42 having a sidewall 44 closed at one end by a bottom portion 46 and at the other end by a panel support 48 having an opening 50 therethrough to provide access to the faceplate panel 12. The back electrode 52 has a potential applied thereto to establish an electrostatic drift field between the back electrode and the photoreceptor 36, which is grounded. Triboelectrically-charged, dry-powdered, light emitting phosphor material, having a charge of the same polarity as the potential applied to the back electrode 52, is injected into the developer tank 42, between the back electrode 52 and the faceplate panel 12. The triboelectrically-charged phosphor material is directed toward the photoreceptor 36 on the faceplate panel 12 by the applied electrostatic drift field.

Abstract: A CRT 10 has an evacuated envelope 11 comprising a funnel 15 having a neck 14 and an open end. The funnel 15 is sealed at the open end to a faceplate panel 12 having a luminescent screen 22 formed on a viewing area of an interior surface of the faceplate panel by an electrophotographic screening process. The screen 22 comprises a multiplicity of different color-emitting phosphor elements. A light absorbing matrix 23 has a first portion that includes a multiplicity of openings therein overlying the viewing area of the faceplate panel, and a second portion providing an imperforate border 123 extending beyond the viewing area. The phosphor elements are disposed within the openings in the matrix. A color selection electrode 25 is mounted within the faceplate panel 12, in proximity to the screen 22. An electron gun 26 is centrally disposed within the neck 14 for generating and directing a plurality of electron beams 28 toward the screen 22.

Abstract: The present invention provides an improvement in a CRT (10) having a tension mask (24) and support frame assembly (35). The support frame assembly (35) is rectangular and has two long sides that parallel a central major axis thereof and two short sides that parallel a central minor axis thereof The mask (24) has a substantially cylindrical contour, being curved along the major axis and straight along the minor axis. The frame assembly (35) includes two first members (36, 38; 136, 138) that parallel the major axis and two second members (40, 42), attached to the ends of the first members, that parallel the minor axis. Each of the first members (36, 38; 136, 138) includes a rigid section (50; 150) and a compliant section (52; 152) cantilevered from the rigid section (50; 150). The compliant sections (52; 152) have a distal end (54; 154) and a proximal end (56; 156). The mask (24) is attached to the distal ends (54; 154) of the compliant sections (52; 152).

Abstract: The present invention provides an improvement in a method of making a plurality of color picture tubes of approximately the same size and including a mix of at least two different types of electron guns therein. The electron guns include each a plurality of electrodes, with each electrode having openings for the passage of three electron beams. The improvement comprises selecting materials for each electrode of the at least two different types of electron guns that will produce a minimum difference in the focus voltage sensitivities between the two different types of electron guns.

Abstract: A plasma display panel is formed by a front plate and a back plate spaced apart from one another so that a discharge space is formed to accommodate a plurality of light generating display cells. To increase the luminance on the front side of the plasma display panel a mirror surface or a plurality of mirror surfaces is provided at the back side of the plasma display panel and/or at side-walls of cells of the plasma display panel.

Abstract: A cathode-ray tube includes a tension mask attached to a rectangular support frame assembly that has two long sides paralleling a central major axis thereof and two short sides paralleling a central minor axis thereof. The frame assembly includes two first members, having oppositely disposed ends, paralleling the major axis, and two resilient U-shaped second members, having a first leg and a second leg attached to the oppositely disposed ends of the first members, paralleling the minor axis. Each of the first members has a compliant portion and a base portion. The mask is attached to the distal ends of the compliant portion. A detensioning rod assembly is disposed between the first and second legs of each of the second members to facilitate varying the tension of the mask.