摘要:
A magnetic shield structure for a color cathode ray tube is provided which can improve color chrominance, rotation redundancy and magnetic field redundancy of the color cathode ray tube, by preventing an electron beam from being moved due to an earth magnetic field, so that the electron beam can be landed on a designated fluorescent material. Accordingly, in a color cathode ray tube including a tension mask assembly comprising a tension mask for color-discriminating an electron beam, and a main frame and a sub frame for supporting the tension mask, and a magnetic shield structure disposed at a funnel, for preventing deflection and distortion of the electron beam, the magnetic shield structure includes a main unit for shielding the inner sides of the funnel, and a front unit where the tension mask assembly is inserted.
摘要:
A color cathode-ray tube includes a panel portion, a neck portion, a funnel portion connecting the panel and neck portions, a fluorescent layer formed on an inner surface of a face plate of the panel portion, a shadow mask disposed opposite to the fluorescent layer, an electron gun housed in the neck portion, and an internal magnetic shield disposed in the funnel portion. The internal magnetic shield is formed in a substantially quadrangular pyramid-shape having a substantially rectangular first opening with a smaller diagonal at one end adjacent to the electron gun and a substantially rectangular second opening with a larger diagonal dimension than the smaller diagonal dimension at the other end adjacent to the shadow mask. The internal magnetic shield has a long side wall including a long side of the first opening and a size adjustment side wall for the long side connecting to the long side wall at one end adjacent to the shadow mask which lie in substantially a single plane, and has a short side wall including a short side of the first opening and a size adjusting side wall for the short side connecting to the short side wall at one end adjacent to the shadow mask.
摘要:
A color CRT having an inner shield being mounted at a frame inside a panel and a funnel to shield an earth magnetic field, in which the inner shield comprises: a vertical portion formed in parallel to the central axis of the CRT and mounted at the frame, a slope portion extended slanted against the central axis of the CRT at a rear side of the vertical portion and a notch with its central portion formed concave at the end portion of the slope portion, the opposite of the frame; and on the assumption that the entire height of the inner shield constructed with the vertical portion and the slope portion is ‘V’, a height (V1) of the vertical portion satisfies the relational expression of 0.18≦V1/V≦0.25, and on the assumption that the shortest height from a starting point of the vertical portion to the notch is V2, the height V1 of the vertical portion satisfies a relational expression of 0.40≦V1/V2≦0.54. By reducing the variation degree that the electron beam is landed is according to the external magnetic field variation, when an image is reproduced, a color spread phenomenon due to a color mixture is prevented from occurring. In addition, since the color spread phenomenon due to a color mixture is prevented, the inner shield contributes to obtain a high image quality, and thus, a reliability of its product is improved.
摘要:
A cathode ray tube includes a pair of plate members (7) facing each other, a pair of supporters (14) adhered to the respective plate members (7) to support the plate members (7), and a shadow mask (6) adhered to the respective plate members (7) while being applied with tensile force. The supporters (14) have crank-shaped steps (15) formed to protrude toward the shadow mask (6). Thereby, an internal moment of a shadow mask structure can be decreased, and thus, displacement of the shadow mask (6) in the axial direction is suppressed even when the shadow mask (6) is expanded by heat generated by impact of electron beams, and q-value deviation is suppressed as well. Moreover, since the crank-shaped steps (15) are helpful in blocking a transverse clearance with a ferrous material, the magnetic properties can be improved.
摘要:
In a circuit and method of controlling the horizontal and vertical screen sizes of a cathode ray tube (CRT) monitor, the circuit includes a horizontal screen size compensation circuit, an east-west correction signal controller, a vertical screen size compensation circuit, and a vertical screen size correction signal controller. The horizontal screen size compensation circuit compares the voltage value of a horizontal screen size correction signal with the voltage value of a horizontal reference voltage to obtain first and second horizontal current signals. In response to a horizontal control signal, the horizontal screen size compensation circuit outputs a horizontal correction current signal obtained by subtracting a horizontal variable current signal from the first horizontal current signal. The vertical screen size compensation circuit compares the voltage value of a vertical screen size correction signal with the voltage value of a vertical reference voltage to obtain first and second vertical current signals. In response to a vertical control signal, the vertical screen size compensation circuit selects one of first and second vertical correction current signals and outputs the selected signal as a vertical correction current signal.
摘要:
A color cathode-ray tube includes a panel portion, a neck portion, a funnel portion connecting the panel and neck portions, a fluorescent layer formed on an inner surface of a face plate of the panel portion, a shadow mask disposed opposite to the fluorescent layer, an electron gun housed in the neck portion, and an internal magnetic shield disposed in the funnel portion. The internal magnetic shield is formed in a substantially quadrangular pyramid-shape having a substantially rectangular first opening with a smaller diagonal dimension at one end adjacent to the electron gun and a substantially rectangular second opening with a larger diagonal dimension than the smaller diagonal dimension at the other end adjacent to the shadow mask. The internal magnetic shield has a long side wall including a long side of the first opening and a size adjustment side wall for the long side connecting to the long side wall, and has a short side wall including a short side of the first opening and a size adjusting side wall for the short side connecting to the short side wall.
摘要:
In a cathode ray tube us a glass panel having a difference in thickness between a central region and a peripheral region of a face portion, the glass panel having an outer surface with a colored film formed thereon, the colored film being thin in film thickness in an area corresponding to a thick part of the face portion of the glass panel and thick in film thickness in an area corresponding to a thin part of the face portion of the glass panel so as to reduce the difference in transmittance resulting from the difference in thickness between the central region and the peripheral region of the face portion of the glass panel. As another embodiment, the colored film comprises a film having a light color tone in an area corresponding to a thick part of the face portion of the glass panel and a dark color tone in an area corresponding to a thin part of the face portion of the glass panel.
摘要:
A panel glass having a surface treating film formed on a substrate glass so that an overall transmittance distribution within an effective picture plane satisfies a specific mathematical expression, whereby, even with a flattened panel glass, a uniform-brightness image can be observed with a good contrast, and occurrence of a double image is suppressed.
摘要:
The present invention relates to a color display device comprising a color display tube (1) with a front portion having a truncated cone (3), an element (5) for generating a plurality of electron beams, a shielding (9) of ferromagnetic material extending substantially parallel to the truncated cone (3), and a demagnetizing device having at least two demagnetizing coils (11,12) extending along the outer circumference of the cone (3). The demagnetizing device is arranged to energize the coils (11,12) simultaneously and with a phase difference, resulting in the generation of a rotating magnetic field. As the magnetic field rotates, it can be arranged to substantially coincide with the shape of the shielding (9), resulting in a magnetic field that is parallel to the shielding (9) over a larger part of the shielding surface. This improves the demagnetizing procedure, leading to a better landing performance of the electron beams.
摘要:
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.