JPH0713173Y2 - Fluorescent tube - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a fluorescent arc tube in which electrons emitted from a linear cathode are made to strike a display segment of an anode to which a high voltage is applied to emit light.

[0002]

2. Description of the Related Art A fluorescent arc tube as a light emitting cell constituting a large screen for graphic display has a linear cathode inside an airtight envelope, and an anode which is a part of the airtight envelope. Three display segments of RGB are provided on the inner surface of the substrate.
A picture element is formed as a pair of anodes, and a control electrode is provided between the linear cathode and the picture element. Generally, in one arc tube, a plurality of sets of the picture elements and electrodes are arranged at a predetermined pitch.

Since a large number of the above-mentioned fluorescent luminous tubes are arranged in a plane to form a large screen, the picture element pitch between adjacent fluorescent luminous tubes is the same as the picture element pitch in the fluorescent luminous tubes. There is a need to. In practice, a space equal to or larger than the thickness of the two envelopes is required between the picture elements of the adjacent fluorescent light emitting tubes, so that the picture element pitch in the fluorescent light emitting tube must be determined accordingly.

However, in order to increase the screen resolution,
The picture element pitch in each arc tube must be made as small as possible, and in order to increase the screen brightness, the light emitting area of the display segment must be expanded as much as possible without expanding the picture element pitch.

In order to achieve such a technical problem, it is necessary to reduce the picture element pitch between the adjacent fluorescent light emitting tubes, and for that purpose, the picture elements are enclosed in an envelope in the fluorescent light emitting tube. Should be placed as close as possible to the side wall of the.

However, when the picture element is arranged close to the side wall of the envelope in the fluorescent light emitting tube, the position corresponding to the end of the linear cathode also becomes the light emitting region. Since the edge of the linear cathode has a low electron emission capability due to the fact that the supporting member receives heat, etc., there is a problem that unevenness in light emission occurs in the display segment of this portion due to this edge cooling effect. .

In order to solve this problem, conventionally, a separator electrode composed of a frame-shaped wall body is provided on an anode substrate to surround a pixel, and the wall body extending vertically from the anode substrate toward the control electrode side. A high voltage was applied to the electron diffusion lens. The separator electrode deflects the electrons from the linear cathode in a diffusing direction, and can guide the electrons to the end portion of the display segment where the electrons do not reach due to the edge cooling effect.

[0008]

However, in the fluorescent light emitting tube having the separator electrode having the above-mentioned structure, the electrons incident in the vicinity of the wall of the separator electrode are effectively deflected. The effect of the diffusing lens fades away as the distance increases. Therefore, as a result, the end of the display segment in the longitudinal direction of the linear cathode does not emit light, or the emission intensity is weakened, and the emission unevenness of the picture element appears.

An object of the present invention is to provide a fluorescent arc tube having a separator electrode capable of effectively diffusing electrons and compensating for the edge cooling effect of a linear electrode to allow the entire surface of a display segment to emit light. I am trying.

[0010]

The fluorescent light emitting tube of the present invention comprises:
A linear cathode, a control electrode for controlling electrons emitted from the linear cathode, a longitudinal direction along the linear cathode, an anode conductor to which a positive potential is applied, and an anode conductor provided on the anode conductor. In a fluorescent light emitting tube having a display segment having a phosphor that receives electron bombardment inside an airtight envelope, the length of the linear cathode in the longitudinal direction is shorter than the length of the display segment in the same direction. An opening formed so that the length of the linear cathode in the direction orthogonal to the longitudinal direction is substantially the same as the sum of the lengths of a plurality of display segments arranged in the same direction in the same direction, A separator electrode to which the same potential as that of the anode conductor is applied is provided between the control electrode and the display segment so that the opening corresponds to the predetermined plurality of display segments.

The dimension of the linear cathode in the longitudinal direction is smaller in the opening of the separator electrode than in the display segment. The electrons incident on the opening are largely deflected in the longitudinal direction of the linear cathode and reach the longitudinal end of the display segment where the end cooling effect of the linear cathode may affect.
Since the electrons do not spread in the direction orthogonal to the longitudinal direction of the linear cathode, there is no inconvenience such that adjacent display segments in the same direction leak and emit light.

[0012]

EXAMPLE A fluorescent arc tube 1 of one example shown in FIGS. 1 and 2.
Has a box-shaped airtight envelope 2. The anode substrate 3 of the airtight envelope 2 has a light-transmitting property, and its inner surface is green,
Phosphors g, r, and b that emit red and blue colors are respectively applied in an elongated rectangular pattern. A conductive light-shielding layer 4 is provided in the space between the phosphors. Phosphor g,
For example, 8 kV is applied to the surfaces of r and b and the conductive light shielding layer 4.
A metal back 5 is provided as an anode conductor to which a high voltage is applied, and the three display segments G, R,
A picture element 6 made of B is formed.

A linear cathode 8 is stretched on the back plate 7 of the airtight envelope 2 for each of the display segments G, R and B. The longitudinal direction (L) of the linear cathode 8 is parallel to the longitudinal direction of each of the display segments G, R, B, and the lengths of both in the same direction are substantially the same. Then, the linear cathodes 8 and the display segments G, R, B are located at positions facing each other in the airtight envelope 2.

A first control electrode 9 is provided on the back plate 7 so as to cover each linear electrode 8 and controls the electrons emitted by each linear electrode 8. A second control electrode 10 is provided on the rear plate 7 above each of the first control electrodes 9 so as to diffuse the electrons passing through the first control electrode 9 toward the anode. .

As shown in FIGS. 1 to 3, the anode substrate 3
A first separator electrode 11 is provided on the top.
The first separator electrode 11 is a frame-shaped electrode that partitions the pixels 6 and 6 and the display segments from each other, and is supplied with a high voltage having the same potential as the anode. This first separator electrode 11
The partition wall 11a can prevent secondary electrons from adjacent display segments and leakage light emission due to mislanding of electrons.

As shown in FIGS. 1 to 3, the anode substrate 3 is
A second separator electrode 12 is provided on the upper side.
The second separator electrode 12 includes the first pixel 6 and the first pixel 6.
The plate-shaped portion 12a facing the second control electrode 10 has a rectangular opening 13 that serves as an electron entrance for each pixel 6 and has a box shape that covers the separator electrode 11.

As shown in FIG. 2, the opening 13 is located at a position corresponding to the center of each picture element 6 and each linear cathode 8 in the longitudinal direction L of each picture element 6 and each linear cathode 8. When the lengths of the display segments G, R, B of the picture element 6 in the longitudinal direction L of the linear cathode 8 are L1 and the length of the opening 13 in the same direction is L2, the relationship of L1> L2 is satisfied. Becomes

As shown in FIG. 1, the length of the opening 13 in the direction W orthogonal to the longitudinal direction L of the linear cathode 8 is W2.
Then, the length W1 of the picture element 6 in the same direction is almost the same.

According to the above structure, the electrons emitted from each linear cathode 8 are easily diffused in the W direction by the second control electrode 10. In the L direction, since the opening 13 of the second separator electrode 12 is set to a dimension shorter than the display segments G, R, B in the L direction, the effect of the diffusion lens by the second separator electrode 12 is strengthened, The deflection of the electrons entering the opening 13 in the L direction becomes large.

FIG. 4 shows a simulation result of this embodiment by electric field analysis. The electrons passing through the opening 13 of the second separator electrode 12 are largely deflected and the end portions of the display segments G, R and B are deflected. Has reached.

The shape of the second separator electrode 12 described above is merely an example, and if the relationship of L1> L2 is satisfied, the dimensional relationship with the display segment in the W direction and the shape of the opening 13 are arbitrary. Further, the structure of the first separator electrode 11 that partitions each display segment is not limited to the above-described embodiment.

The shape of the second separator electrode 12 is merely an example. Further, the structure of the first separator electrode 11 that divides each display segment is not limited to the above embodiment.

Further, the side wall of the second separator electrode may be cut into an arbitrary shape so as to be connected to the opening.

Further, the openings may be divided in the W direction for every three display segments of each picture element.

Alternatively, the opening 13 may be left as it is in the above-described embodiment, and the height of the partition wall of the first separator electrode 11 may be increased so that the upper end of the partition wall faces the vicinity of the opening 13.

[0026]

According to the present invention, since the opening of the separator electrode for deflecting electrons is set shorter than the display segment in the direction of the linear cathode, the action as a diffusing lens becomes more effective, and The edge cooling effect of the cylindrical cathode can be compensated to obtain sufficient light emission over the entire surface of the display segment.

[0027]

According to the present invention, since the opening of the separator electrode for deflecting electrons is set shorter than the display segment in the direction of the linear cathode, the function as a diffusing lens becomes effective and the linear cathode It is possible to compensate for the edge cooling effect and obtain sufficient light emission on the entire surface of the display segment. In addition, since the electrons do not spread in the direction orthogonal to the longitudinal direction of the linear cathode, there is no inconvenience such that adjacent display segments in the same direction leak and emit light.

Further, according to the present invention, even if the positions of the respective display segments and the respective linear cathodes do not completely correspond to each other, the electrons emitted from the linear cathodes are sufficiently deflected so that the entire surface of the light emitting segment emits light. . For this reason, it is possible to reduce the number of linear electrodes and the like and realize an arc tube in which the outer shape on the back plate side is reduced, and it is possible to easily handle the connection leads.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example taken along a cross section orthogonal to the longitudinal direction of a linear cathode.

FIG. 2 is a cross-sectional view of one embodiment of a cutting plane orthogonal to the cutting plane of FIG.

FIG. 3 is an exploded perspective view of a main part of the embodiment.

FIG. 4 is a diagram showing simulation results of electric field analysis in one example.

[Explanation of symbols]

 1 Fluorescent arc tube 2 Airtight envelope 5 Metal back as anode conductor 8 Linear cathode 9 First control electrode 12 First separator electrode 13 Opening g, r, b Phosphor G, R, B Display segment

Claims (1)

[Scope of utility model registration request] 1. A linear cathode, a control electrode for controlling electrons emitted from the linear cathode, and a direction along the linear cathode.
Was the longitudinal direction, in the fluorescent light emitting tube to the display segments with the inside of the airtight envelope provided to the anode conductor and the anode conductor positive potential is applied with a fluorescent material for receiving the bombardment of the electrons, length about the longitudinal direction of the linear cathode
Shorter than the length of the display segment in the same direction, the line
The length of the rectangular cathode in the direction orthogonal to the longitudinal direction is the same direction.
If a certain number of display segments lined up in
A separator electrode provided with an opening formed to be substantially the same as the total number of electrodes, the separator electrode being provided with the same potential as the anode conductor, and the control electrode and the control electrode so that the opening and the predetermined plurality of display segments correspond to each other. A fluorescent arc tube characterized by being provided between display segments.