摘要:
The gun, for use in a television picture tube, comprises a cathode, an apertured control grid, and an apertured screen grid aligned in the order named. The screen grid aperture comprises a rectangular slot portion facing the control grid and a circular portion facing away from the control grid. The slot portion of the aperture, which has a width 2-5 times its depth, creates an astigmatic field that produces underconvergence of the electron beam in the vertical plane only, whereby to avoid and/or compensate for vertical flare distortion of the beam spot at off-center positions on the image screen.
摘要:
The present invention provides an improvement in a color picture tube having an inline electron gun for generating and directing three inline electron beams, comprising a center beam and two outer beams, along initially coplanar paths toward a screen of the tube. The beams pass through a deflection zone adapted to have two orthogonal magnetic deflection fields established therein. A first of the fields causes deflection of the beams perpendicular to the inline direction of the beams, and a second of the fields causes deflection parallel to the inline direction of the beams. The improvement comprises the electron gun including four magnetically permeable members located near the exit of the electron gun in a fringe portion of said deflection zone. A first and a second of the members are located between the center beam path and a first and second outer beam path, respectively. A third and a fourth of said members are spaced from the first and second members, respectively, and are located on the outside of the respective outer beam paths. The first and third members and the second and fourth members have means for bypassing a part of the fringe portion of the first of the two orthogonal magnetic deflection fields, at the members, around the respective outer beam paths, while allowing another part of the same fringe portion, at the members, to pass through the respective outer beam paths. The first and second members have means for bypassing a part of the fringe portion of the first of the two orthogonal deflection fields, at the members, around the center beam path, while allowing another part of the same fringe portion, at the members, to pass through the center beam path.
摘要:
The electron gun, which is especially adapted for use in color picture tubes, comprises in the order named: a cathode, an apertured-plate control grid (G1), an apertured-plate screen grid (G2), and at least two tubular focusing electrodes. The quality of the gun's beam spot is improved by: 1. Establishing an operating electric field between the G2 and G3 which is between about 100 and 400 volts/mil, thereby reducing aberration effects in the beam-forming region of the gun; 2. Making the G2 thick so as to prevent the high G3 voltage from penetrating the region between the G1 and G2, thereby allowing the G1-G2 field to provide a divergent effect on the electron beam prior to beam crossover and thus give a reduced crossover angle; 3. Spacing the main focusing lens at a distance from the G2 so as to provide an optimum filling of the main focus lens with the beam to maximize the object distance of the focusing system; and 4. Structuring the G2 and G3 to provide a flat electrostatic field therebetween to avoid prefocusing action in that region, so as not to cause an effective reduction of the object distance of the focusing system.
摘要:
A color picture tube includes a screen and an improved inline gun for generating and directing three inline electron beams along separate paths toward the screen. The improved electron gun has an asymmetric beam-forming region and an asymmetric main focus lens. The asymmetry of the main focus lens is matched with the asymmetry of the beam-forming region to focus substantially all portions of each of the beams at the screen.
摘要:
A maskless, direct write electron lithography apparatus for accurately and simultaneously writing plural sub-micron patterns on a silicon substrate employs plural parallel electron beams with precise X-Y mechanical translation of the substrate to provide low cost, high throughput integrated circuit (IC) fabrication. Plural compact micro electron gun assemblies arranged in a I×J rectangular grid each simultaneously expose one IC pattern on the substrate, with each electron gun assembly including a K×L array of individually controlled electron guns emitting K×L electron beams. The regular, small spacing between electron beams in each array, i.e., approximately 1 mm or less, requires a correspondingly small X-Y translation of the substrate to write the entire wafer. Each electron gun array includes plural AC blanked cathodes and DC biased plates having plural aligned beam passing apertures. A computer controlled pattern generator synchronized with wafer X-Y translation controls the duration and timing of the cathode blanking signals.
摘要:
A multi-beam color index cathode ray tube (CRT) includes vertically spaced, horizontal phosphor stripes on the inner surface of its display screen. The parallel phosphor bands are arranged in groups of three, with each phosphor stripe in a group providing a respective one of the three primary colors of red, green and blue. An electron gun directs three electron beams onto the display screen, with the three electron beams deflected over the display screen in unison in a raster pattern. The three electron beams are focused in the form of three spots on the display screen, with each spot coincident with a respective horizontal phosphor stripe of a given color. The intensity of each electron beam is independently modulated as it sweeps across the width of the display screen by a respective color video signal in accordance with the displayed image. The three electron beams are each provided with a horizontally elongated cross section, with convergence of the beams provided by a plurality of multi-pole adjustable magnets. By horizontally elongating and vertically offsetting the beams, the vertical spacing between the electron beams as well as between the horizontal phosphor stripes may be reduced for improved video image resolution. The closely spaced electron beams may be focused with a conventional main focusing lens employing a common beam-passing aperture, with electron beam alignment with the horizontal phosphor stripes provided via a beam responsive UV emitter/sensor combination and feedback control arrangement.
摘要:
An electron gun for use in a cathode ray tube (CRT) includes a cathode, a low voltage beam forming region (BFR), and a high voltage deflection focus lens disposed in the beam deflection region of the CRT's magnetic deflection yoke for simultaneous and coincident focusing and deflection of the electron beam on the CRT's display screen. The deflection lens includes a plurality of first focus grids disposed in the CRT's neck portion including a spaced first pair of grids each having respective beam passing apertures, with one of the beam passing apertures horizontally offset and the other beam passing aperture vertically offset from the electron beam axis. Other grids disposed on opposed sides of each of the first pair of grids have respective beam passing apertures centered with respect to the electron beam axis and are maintained at a fixed focus voltage. A dynamic focus correction voltage which varies with electron beam deflection is applied to each of the first pair of grids for compensating for asymmetric off-axis electron beam defocusing at all points on the CRT's faceplate. This dynamic off-axis defocusing correction is equally applicable in a single beam, monochromatic deflection lens CRT as well as in a multi-beam, color deflection lens CRT.
摘要:
A limiting aperture disposed in a low voltage, beam forming region (BFR) of an electron gun in a cathode ray tube (CRT) provides reduced electron beam spot size with low power dissipation. The limiting aperture is located in a low voltage, electrostatic field-free region, preferably in the screen grid electrode G.sub.2, where the field-free region is formed by increasing the thickness of the screen grid electrode G.sub.2 to 1.8 times the diameter of a pair of circular recessed portions in opposing surfaces of the screen grid electrode G.sub.2 which are separated by the small diameter limiting aperture on the electron gun's axis through which the beam is directed. A narrow, relatively electrostatic field-free zone is thus formed in the center of the screen grid electrode G.sub.2 which is maintained at a relatively low voltage, i.e., ranging from approximately 300 V to less than 12% of the anode voltage. The outer electrons in the relatively low energy electron beam are intercepted by the limiting aperture to provide a small, well defined beam spot size on the CRT screen.
摘要:
An electron beam device includes an electron beam source, plural spaced plates having aligned apertures through which an electron beam is directed, an electrostatic focusing arrangement, and plural electrostatically charged deflection plates for deflecting the beam and displacing it over a target surface. The apertures in the spaced plates are of deceasing size in the direction of travel of the electron beam for intercepting the outer periphery of the beam and providing a beam of reduced cross section. The electron beam is simultaneously deflected by the deflection plates and focused by the electrostatic focusing arrangement. The electrostatic focusing arrangement includes first and second focusing elements through which the beam is directed which are disposed along the beamline and adjacent the upper and lower end portions, respectively, of the beam deflection plates. The electron beam device is of small size, permitting plural devices to be arranged in two- and three-dimensional compact matrix arrays for dense electron beam lithography arrangements such as for use in the simultaneous manufacture of large numbers of semiconductor devices to boost the throughput in integrated circuit manufacture inexpensively.
摘要:
A video display system includes a passive display panel such as a liquid crystal display (LCD) panel including a first plurality of horizontally aligned transparent conductive scanning electrodes and a second plurality of vertically aligned transparent conductive signal electrodes disposed on opposed surfaces of the panel. Light directed onto the aft surface of the display panel is transmitted through the panel as each horizontal linear array of first scanning electrodes is turned "ON" with the horizontal linear arrays sequentially turned on for vertically scanning the display panel in a step wise manner. Time varying video image information is provided to the vertically aligned electrodes. Liquid crystal display backlighting is provided in the form of a thin, elongated light beam of uniform intensity directed onto the display panel's aft surface. The backlighting beam is vertically displaced, such as from top to bottom, in a stepwise manner over the display panel synchronously with the turning "ON" of the horizontal scanning electrodes such that the beam illuminates only the horizontal linear array of the scanning electrodes which is turned "ON" i.e., only that portion of the display panel containing visible video information, for improved video image contrast and more efficient backlighting of the display panel. The scanning back light beam is provided by a partitioned or sectioned light panel, such as a plasma discharge panel (PDP), where the partitions are each aligned with a respective horizontal array of scanning electrodes and sequentially turned "ON" synchronously with actuation of the scanning electrode arrays.