摘要:
A display tube comprises an electron source (10), a module (20) provided with a guidance cavity (25R, 25G, 25B) for guiding electrons emitted by the electron source (10) to an exit aperture (27R, 27G, 27B) of the guidance cavity (25R, 25G, 25B), and beam-shaping means (30) for forming an electron beam (EBR, EBG, EBB) from guided electrons leaving the exit aperture (27R, 27G, 27B). The electron beam (EBR, EBG, EBB) travels towards a display screen (3). The beam-shaping means (30) are arranged to constitute, in operation, an electron lens for shaping the electron beam (EBR, EBG, EBB) so as to compensate for unwanted distortions of the shape of the electron beam (EBR, EBG, EBB) between the exit aperture (27R, 27G, 27B) and the display screen (3). These distortions are, for example, caused by the magnetic field of deflection means (2). The image quality of the display tube is improved.
摘要:
A prefocusing lens section comprises a screen electrode (G2) and an additional electrode (G3). The main lens section comprises a focusing electrode (G5), an anode electrode (G6), and an intermediate electrode (GM) disposed between the focusing electrode and the anode electrode. The focusing electrode and the intermediate electrode comprise cylindrical electrodes (G5−3) and (GM−1) on their respective counter faces in at least one of them each. The intermediate electrode and the anode electrode comprise cylindrical electrodes (GM−3) and (G6−1) in their respective counter faces. A voltage having a level higher than a focusing voltage and lower than an anode voltage is impressed on the additional electrode and the intermediate electrode.
摘要:
An electron gun (10) as for a cathode ray tube includes a plurality of electrodes biased at different potentials to electrostatically shape and focus the one or more electron beams produced thereby. A dynamic focus grid (G6) is driven by a substantial ac voltage signal at the horizontal line rate, which signal is undesirably coupled through parasitic capacitance to an intermediate grid (G7) located between the dynamic focus grid (G6) and the gun anode (G8). A resistive biasing network includes a high value resistance to divide the anode potential to develop bias potential for the intermediate grid and a capacitance to ac couple the intermediate grip to ground potential. The resistance and/or capacitance are formed in a plural layer ceramic circuit. The ceramic circuit may be located in the tube neck on or with the electron gun.
摘要:
An electron gun structure (22) comprises at least one additional electrode (Gs) arranged along an equipotential surface formed between a focusing electrode (G3) and an anode electrode (G4), which form a main lens. For no deflection, a predetermined voltage applied to the additional electrode (Gs) corresponds to the potential of the equipotential surface in which the additional electrode (Gs) is arranged. For deflection, the convergence in vertical directions (Y) is different from that in horizontal directions (X) as the value of (Vs-Vf) / (Eb-Vf) varies with the increase in deflection of the electron beam, where (Vf) is the voltage applied to the focusing electrode (G3), Eb is the voltage applied to the anode electrode (G4), and Vs is the voltage applied to the additional electrode (Gs).
摘要:
A resistive focusing lens structure for an electron beam device wherein the total resistance of the focusing lens structure is larger than 2.5 G OMEGA and the absolute value of the temperature coefficient of resistance is smaller than 250.10 K . Preferably, said resistive focusing lens structure comprises a resistance layer of a fired suspension of a conductive material of a mixture of a lead ruthenate, a lead titanate and a ruthenium oxide in a glass formed of silicon dioxide, aluminum oxide and lead oxide.
摘要:
The invention relates to a cathode ray tube having an electron gun (10) which is provided with a so-called Aberration Reducing Triode (15). The ART (15) pre-focuses the electron beam (EB) such that outer rays in the pre-focus lens (20) are near the center of the electron beam (EB) in the main lens (30). Spherical aberrations are reduced, thereby. However, under given circumstances, moirepattems can appear in the image formed on the display screen (50), especially in parts of the image having a low brightness. According to the present invention, the pre-focus lens (20) in the ART (15) is arranged such that the pre-focusing effect thereof is reduced when the beam current of the electron beam (EB) is below a predetermined threshold beam current. This reduces or eliminates the moirepattems.
摘要:
An electron gun has a pluraltiy of grid electrodes for focusing electron beams radiated from cathodes, at least one of said grid electrodes having a cylindrical body containing a plate member. The plate member has a central electron-beam-passing-aperture and two side apertures. At least one of the two side apertures is contoured by a first circular arc and a second circular arc, two first vertical lines respectively extending outward from either ends of the first circular arc, two second vertical lines respectively extending outward from either ends of the second circular arc, and two connecting lines respectively connecting each of outer ends of the first vertical lines to each of outer ends of the second vertical lines. The electron gun improves the degree of freedom in controlling shapes of beam spots focused on a phosphor screen, thereby heightening the resolution of the cathode ray tube.
摘要:
An electron-beam-pumped laser includes a cathode-ray tube containing a laser crystal, an electron gun for producing an electron beam including a multi-element focusing electrode layer on an inner surface of the tube for effecting focusing of the beam on the laser crystal, and a multi-element deflection electrode layer on an inner surface of the tube for effecting scanning of the beam across the laser crystal. The laser crystal is disposed on a metal heat-conductive support which is adapted for accurately positioning the laser crystal in closely spaced relationship with respect to the electron gun and to a laser light emitting window of the tube.
摘要:
Electron-optical device having two elongate emitting regions arranged symmetrically with respect to a longitudinal axis for producing two electron beams having an elongate cross section. By means of electron grids, the two beams are focused at the same point of an electron target arranged transversely to the longitudinal axis and having a short central axis and a long central axis. The elongate emitting regions have their smallest cross section parallel to the scanning direction of a device, cooperating with the electron-optical device, for scanning a target arranged transversely to the longitudinal axis.