Abstract:
A projection tube apparatus includes: a valve made up of a face panel having a screen face on its external face, a funnel connected to a rear portion of the face panel, and a neck portion; an electron gun that emits an electron beam and is housed in the neck portion; and a deflection device mounted at an outer circumference of the funnel on the neck portion side. The deflection device at least includes: horizontal deflection coils that generate a horizontal deflection field for deflecting the electron beam in the horizontal direction; vertical deflection coils that generate a vertical deflection field for deflecting the electron beam in the vertical direction and is disposed outside the horizontal deflection coils; and a ferrite core disposed outside the vertical deflection coils. A distance Ls between an end portion of the horizontal deflection coils on the screen face side and the screen face is set to 55 mm≦Ls≦80 mm.
Abstract:
A glass bulb for use in a projection TV cathode-ray tube includes a face part having a fluorescent film, wherein the face part includes: a light-transmitting region that contains no contaminant having an effective diameter W of at least a defective reference value φ; and a region extending from the surface of the fluorescent film in the light-travel direction, which is located within a reference depth TS and only contains a contaminant having an effective diameter W of at most a measurement reference value φ′, wherein the defective reference value φ is from 0.15 to 0.35 mm; the measurement reference value φ′ is from 0.07 to 0.15 mm; and the reference depth TS is from 2.6 to 4.0 mm. Such a glass bulb can be used for a cathode-ray tube in a wide-screen projection TV and can be prevented from causing a defective projection image on a screen.
Abstract:
There can be avoided a contrast degradation caused by stray light generated from a liquid-cooling type cathode-ray tube apparatus incorporated in a projection type television apparatus. Stray light (7) emitted from a flange (peripheral edge) (11a) of a lens (11) out of a coupler (10) and the lens (11) disposed on the front face of a CRT 1 of a liquid-cooling type cathode-ray tube apparatus 5 is shield by light shielding members (ribs) (20), (20a) disposed in the coupler (10) and/or a lens plate (13).
Abstract:
An electron-optical device comprising a cathode ray tube with an envelope comprising an electron gun for producing an electron beam, whose inner surface carries a multi-element layer electrode such as a helical structure formed from a high-ohmic resistance material, which structure constitutes a focusing lens. A deflection system is used for moving the focused electron beam across a laser crystal arranged in the tube. Due to the laser action of the crystal, a scanning laser is realized. The laser light leaves a window in the tube envelope. The window extends at an angle between 20.degree. and 60.degree. to the longitudinal axis of the tube which is parallel to the electron beam incident on the laser crystal. Used in, inter alia, projection tubes and electron beam-pumped lasers (for example, scanning lasers).
Abstract:
A picture tube and lens system are combined to form a picture display device for use in a projection device. The lens system is mounted in an extension of the tube envelope.
Abstract:
The present invention enlarges the effective display area of a CRT for projecting while maintaining the strength of the panel necessary to allow for normal usage without breaking. The inside portion of the effective display area inside the rectangular display area is of a predetermined radius, and protrudes inward, extending in all directions. The four corners of the display area are outside of the circular boundary line comprised of the standard thickness Tf. Non-display areas H which are outside the boundary line are flat or protuberant, and have a thickness greater than the standard thickness Tf. Accordingly, with the present invention, the effective display area A2 can be made larger than previous effective display areas A1 in the prior art, which could not extend beyond a border that included the four corners, while maintaining overall the necessary strength.
Abstract:
A cathode ray tube device employed in a projection apparatus for projecting an image on a screen. The cathode ray tube device includes a supporting frame mounted on a rim of a front panel section of the cathode ray tube, a lens plate in the form of a frame having a center aperture, and having a projection lens system attached to it, and a positioning supporting member detachably mounted on a mounting base plate of the projection apparatus and adapted for positioning the supporting frame and the lens plate with respect to the mounting base plate for detachably supporting the supporting frame and the lens plate by the mounting base plate. The positioning supporting member has a lens plate supporting surface for supporting the lens plate at a tilt angle corresponding to a convergence angle with respect to the mounting base plate and a supporting frame supporting surface for positioning and supporting the supporting frame at a tilt angle corresponding to an elevation with respect to the lens plate and at a distance corresponding to a back focal length at back of the lens plate for accurately setting the convergence angle, elevation and the back focal length.
Abstract:
A monochrome cathode ray tube including a magnetic focusing device provided with means for generating a static magnetic focusing field. These means surround the neck of the cathode ray tube without contacting this neck, and a system of correction coils for generating an additional focusing field and 2-, 4- and/or 6-pole fields is provided coaxially between these means and the neck of the tube.
Abstract:
A high-efficiency cathodoluminescent screen for high-luminance cathode-ray tubes has a design which makes possible a considerable improvement of the luminance. The cathodoluminescent screen of the invention includes a glass substrate (11) carrying a luminescent screen (12) consisting of luminophor grains. According to a characteristic of the invention, an intermediate screen (15) is inserted between luminescent screen (12) and substrate (11), with the intermediate screen (15) having a refraction index n1 which is clearly greater than refraction index n0 of substrate (11). As a result of this arrangement, a considerable part of the light which penetrates intermediate layer (15) is reflected in the direction of luminescent layer (12), so that this light can then be rediffused to substrate (11), i.e., to use, with an emission indicatrix which is much more greatly concentrated on the axis than in the prior art.
Abstract:
Phosphors used in colour cathode ray tubes, particularly but not exclusively projection television tubes, have colour point standards or chromaticities modified to conform to European Broadcasting Union (EBU) standards by disposing an interference filter in the light-path from the phosphor, for example, between the phosphor and the faceplate, which has a peak gain greater than unity over a selected part of the frequency spectrum. As a result, an efficient broadband phosphor can be employed to obtain the desired chromaticity and thereby increase the white-D luminance of projection television systems.