Electric lamp and discharge devices – Cathode ray tube – Beam deflecting means
Patent
1983-11-16
1986-11-04
Moore, David K.
Electric lamp and discharge devices
Cathode ray tube
Beam deflecting means
313428, H01J 2970
Patent
active
046212159
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a multi-beam electron gun having a common main electron lens to converge a plurality of electron beams and particularly to a multi-beam electron gun suitable for use with a flat type color cathode ray tube.
BACKGROUND ART
A flat type color cathode ray tube is provided with an electron gun which is extended along the direction parallel to the surface of a phosphor screen to make an envelope flat. The flat type cathode ray tube of this kind includes a flat tube envelope 1 as shown in FIGS. 1 and 2. This tube envelope 1 comprises, for example, a glass panel portion 1a, a glass funnel portion 1b, which forms a flat cavity 2 between the former and the latter and is made narrower as it comes closer to one side, namely, made as the form of a funnel (funnel shaped), and a glass neck portion 1c which is located at one narrow side thereof to communicate with the flat cavity 2.
Within the flat envelope 1 are placed a phosphor screen 3 and an opposing electrode 4 facing to the phosphor screen on its flat surface in the flat cavity 2. Both of them are placed in parallel to each other relative to the direction perpendicular to the flat surface of the tube envelope 1. On the inner surface of the panel portion 1a, for example, of the tube envelope 1 are deposited a target electrode 5 made of, for example, a transparent electrode and the phosphor screen 3 and the opposing electrode 4 made of, for example, a metal plate is located on the inner surface of the funnel portion 1b to oppose the former.
The phosphor screen 3 comprises stripe or dot like predetermined phosphor patterns which will emit, for example, red, green and blue light. In facing relation to this phosphor screen 3, an electrode 13 which determines an electron beam landing position, for example, aperture grille or shadow mask and the like is located to allow electron beams corresponding to respective color, which will be described later, to land on the phosphors of corresponding colors.
On the other hand, an electron gun 7 is located within the neck portion 1c, which is arranged such that electron beams emitted from the electron gun pass through the substantially center between the phosphor screen 3 and the opposing electrode 4 and then extends along the direction parallel to the surface of the phosphor screen 3.
The electron gun 7 can be constructed as a multi-beam single electron gun in which, as shown in FIGS. 3 and 4, three cathodes K.sub.R, K.sub.G and K.sub.B corresponding to, for example, red, green and blue colors are arranged on the horizontal plane, namely, in line with one other. A first grid G.sub.1, a second grid G.sub.2, a third grid G.sub.3, a fourth grid G.sub.4 and a fifth grid G.sub.5 which are common thereto are located in turn. The third to fifth grids G.sub.3 to G.sub.5 constitute a main electron lens L of, for example, the unipotential type and a convergence means C is located at the rear stage of the fifth grid G.sub.5. The convergence means C comprises a pair of inner deflection plates C.sub.1 and C.sub.2 which are arranged symmetrically on both sides of the axis of the electron gun 7, namely, on the plane substantially perpendicular to the phosphor screen and are symmetrical to each other in the longitudinal direction relative to the horizontal plane passing through the axis of the electron gun 7. Outside the respective deflection paltes C.sub.1 and C.sub.2 located are a pair of outer deflection plates C.sub.3 and C.sub.4, each of which is opposed in parallel relation to the deflection plates C.sub.1 and C.sub.2, are similarly arranged along the above mentioned plane perpendicular to the phosphor screen and are symmetrical to each other on both sides of the axis of the electron gun. In addition, they are arranged symmetrical to each other in the longitudinal direction relative to the horizontal plane passing through the axis of the electron gun. The pair of inner deflection plates C.sub.1 and C.sub.2 are electrically coupled to the fifth grid G.sub.5 of the last stage to which a high
REFERENCES:
patent: 3181027 (1965-04-01), Geer
patent: 3949262 (1976-04-01), Ohkoshi et al.
patent: 4451756 (1984-05-01), Sato et al.
Moore David K.
Sony Corporation
Wieder K.
LandOfFree
Convergence system for a multi-beam electron gun does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Convergence system for a multi-beam electron gun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Convergence system for a multi-beam electron gun will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-698318