JPH0762995B2 - Display tube for light source - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a light source display tube which constitutes a pixel of a large-screen display device, particularly a color display device.

[Conventional technology]

When a large-screen display device is constructed by arranging single-color display tubes utilizing the light emission of the phosphor as one pixel in a matrix, there is a space at the connection portion of each single-color display tube, and it is difficult to improve the resolution. Higher resolution may result in higher cost.

Therefore, conventionally, for example, a composite type light source display tube disclosed in JP-A-62-10849 has been proposed.

2 and 3 are a front view and a sectional view taken along the line III-III of the basic structure of the composite type light source display tube, and FIG. 4 is an exploded perspective view of a part thereof, in which R (red) is shown. , G (green) and B (blue) phosphors are arranged in a matrix of 3 × 3 pixels with the number of pixels being the phosphor screen having each pixel as one pixel.

In these figures, reference numeral 1 denotes a vacuum envelope as a glass tube which is hermetically sealed by a front panel 2, a back plate 3 and a tubular side plate 4, and an inner surface of the front panel 2 has a three-color phosphor. Each of R, G, and B is applied and arranged in a matrix as a unit pixel, and a fluorescent display portion 5 composed of 3 × 3 pixel fluorescent screens 5R, 5G, and 5B is formed. Here, phosphor screen 5R, 5G
The subscripts of 5B and 5B correspond to red (R), green (G) and blue (B), respectively.

Reference numeral 6 denotes a plurality of skirt-type accelerating anodes arranged around the respective fluorescent screens 5R, 5G and 5B of the fluorescent display section 5 so as to correspond to each other.
6 _1, 6 _2, an anode electrode group composed of ........., these accelerating anodes 6 _1, 6 _2, a high voltage through the external terminals 16 is adapted to be applied to ..........

Reference numeral 7 denotes a cathode electrode group in which electron emission cathodes 7 _{11 to} 7 ₃₃ (not shown) are independently arranged in correspondence with the respective fluorescent screens 5R, 5G, 5B of the fluorescent display unit 5. 7
_{11-7 33} a pair of support 17a, each of the both ends are fixed on the rear plate 3 is supported between 17b. Here cathode 7
The 1st and 2nd subscripts of _{11 to} 7 ₃₃ are 1 to 3 respectively
It corresponds to the rows and the first to third columns.

Note that the cathodes 7 _{11-7 33,} for example, a straight thermal who oxide coating to indirectly heated or tungsten was coated with oxide on the Ni sleeve can be used.

Reference numeral 8 is a grid electrode group composed of control grids 8 ₁ to 8 ₃ for row selection arranged between the cathode electrode group 7 and the fluorescent display section 5. As shown in FIG. The grids 8 ₁ to 8 ₃ correspond to the respective fluorescent screens 5R, 5G and 5B of the fluorescent display section 5 in the row direction thereof and the cathodes 7 _{11 to} 7 respectively.
Electron passage holes 9 _{1 to} 9 ₃ are provided to pass the electron beam 11 from ₃₃ as a non-focused beam.

10 is the back side of the cathode electrode group 7, that is, the vacuum envelope 1
On the back plate 3 forming a part of each of the fluorescent display units 5 corresponding to the respective fluorescent screens 5R, 5G and 5B, the striped patterns shown in FIG. Is a back electrode group consisting of back electrodes 10 ₁ to 10 ₃ for column selection, and these back electrodes 10 ₁ to 10 ₃ are formed of a conductor layer of Ag or the like.

Then, each of the back electrodes 10 ₁ to 10 _3, each cathode 7 _11-7
By applying a positive potential of the negative and 0V or several V with respect to ₃₃ of the potential, which is intended to control the electron beam 11 to be emitted from their cathode 7 _{11-7 33.}

Reference numeral 12 is a lead wire as an external terminal for drawing out each electrode of the cathode electrode group 7, the grid electrode group 8 and the back electrode group 10 from the back plate 3.

Next, the operation will be described. First, the back electrode 10 ₁ to 10 ₃
When a negative potential relative to the potential of but cathode 7 _{11-7 33,} because around these cathode 7 _{11-7 33} is surrounded by a negative potential, electrons from the cathode 7 _{11-7 33} control grid
8 ₁ to 8 ₃ and the accelerating anodes 6 ₁ , 6 ₂ , ... do not flow to the cut-off state.

Therefore, the addition of positive potential of 0V or several V relative to the potential of the cathode 7 _{11-7 33} to the back electrode 10 ₁ to 10 _3, the electron beam 11 emitted from the cathodes 7 _{11-7 33} control grid It flows toward 8 ₁ to 8 ₃ .

At this time, the potential of each control grid 8 ₁ to 8 ₃ is changed to the cathode.
When the potential is negative with respect to 7 _{11 to} 7 ₃₃ , these control grids are
The electron beam 11 cannot pass through the electron passage holes 9 _{1 to} 9 _{3 of} 8 ₁ to 8 ₃ and the electron beam 11 does not flow to the accelerating anodes 6 ₁ , 6 ₂ , ... The phosphor screens 5R, 5G, and 5B do not emit light.

Then, the potentials of the control grids 8 ₁ to 8 ₃ are changed to the cathodes 7 _{11 to} 7 _33.
On the other hand, when the potential is positive, the electron beams 11 pass through the electron passage holes 9 _{1 to} 9 _{3 of} these control grids 8 ₁ to 8 ₃ respectively, and each phosphor screen 5R, 5G, and 5B emits light.

Therefore, the control grids 8 ₁ to 8 _{3 of} the grid electrode group 8 and the back electrodes 10 ₁ to 10 _{3 of the} back electrode group 10 arranged in a matrix corresponding to the phosphor screens 5R, 5G, and 5B, respectively. By selectively controlling the drive (dynamic drive),
Only the fluorescent surfaces 5R, 5G, and 5B where the two electrodes intersect can be selectively caused to emit light.

As described above, three phosphor screens 5R, 5G, and 5B made of phosphors of three colors are provided on the inner surface of the front panel 2 which constitutes the vacuum envelope 1.
They are arranged in a matrix of × 3 pixels, and each of these phosphor screens 5R, 5
By providing the cathode electrode group 7, the grid electrode group 8 and the back electrode group 10 corresponding to G, 5B, it is possible to obtain a display tube for a light source of high brightness light emission.

Therefore, when assembling a large-screen color display device using this light source display tube as one cell, the space between each pixel becomes narrower than that in the case where a single color tube with one pixel is used, and the resolution can be improved. ,
The number of parts and the number of manufacturing steps can be reduced. Further, not only the structure can be simplified and the cost can be reduced, but also the weight of the display device can be reduced.

In addition, in the illustrated example, the case where the phosphor surfaces made of R, G and B tricolor phosphors are arranged in a matrix of 3 × 3 pixels on the inner surface of the front panel 2 is shown, but the invention is not limited to this. In the vacuum envelope, phosphor screens each having one phosphor as one pixel are arranged in a matrix of arbitrary m × n pixels (where m and n are arbitrary integers), and a grid electrode group is arranged accordingly. The arrangement configuration of the back electrode group can be changed.

[Problems to be Solved by the Invention]

Since the conventional light source display tube is constructed as described above, when the electrons emitted from the respective cathode 7 _{11-7 33} is accelerated by the acceleration anode 6 _1, 6 ₂ ... One that Section concentrates on the sharp tip of these skirts, and discharge is generated in this sharp section, so that the unfocused beam is uniformly and efficiently emitted from the cathode 7 ₁₁ − 7 ₃₃ to each of the phosphor screens 5R, 5G, and 5B. There was a risk that it would not be irradiated.

The present invention has been made in view of the above, and an object thereof is to obtain a display tube for a light source, which is capable of irradiating a phosphor screen with a non-focused beam uniformly and efficiently by not forming a sharp portion in an accelerating anode.

[Means for Solving the Problems]

In the display tube for a light source according to the present invention, the accelerating anode is installed in front of the fluorescent display section as a plate with a flat shadow mask having a plurality of window holes for transmitting the unfocused beam.

[Action]

The accelerating anode according to the present invention has a flat plate shape between the fluorescent display portion and the control grid and has no sharp portion where electrons are likely to concentrate when passing the unfocused beam through the window. No discharge phenomenon occurs in any of the above, and therefore, the non-focused beam (electron beam) acts to uniformly and efficiently irradiate the fluorescent surface of the fluorescent display unit.

Example of Invention

An embodiment of the present invention will be described below with reference to the drawings. First
In the figure, 21 is a accelerating anode, which is a plurality of window holes for transmitting the unfocused beam from the cathode 7 _{11-7 33} on a single conductive plate made of those having a 22, and the cathode
It is made as a shadow mask plate provided for 7 _{11 to} 7 ₃₃ . In addition, this accelerating anode 21 has a phosphor screen 5R, 5
G, is provided between the 5B and the control grids 8 _{1-8 3,} electrical which the fluorescent screen 5R, 5G, and 5B and electronic antireflection aluminum film provided on the inner surface of the front panel 2 (not shown) It is connected to the.

Next, the operation will be described.

Now, when an electron is emitted from any of the cathodes 7 _{11 to} 7 ₃₃ , the unfocused beam of the electron passes through the corresponding window hole 22 through _{one of} the control grids 8 ₁ to 8 ₃ corresponding to this, When passing through this window 22, it is accelerated by receiving a high-voltage electric field, and is irradiated onto predetermined phosphor screens 5R, 5G, 5B. In this case, since the accelerating anode 21 has a flat plate shape as a whole, the potential gradient with respect to the unfocused beam becomes uniform over the entire surface, so that the unfocused beam does not concentrate only on a part of the accelerating anode 21. Therefore, the unfocused beam is efficiently applied to each of the fluorescent surfaces 5R, 5G, and 5B. As a result, an image obtained as a whole color display device can be displayed clearly and brightly.

The window hole 22 can be used by arbitrarily selecting a round shape or a rectangular shape.

〔The invention's effect〕

As described above, according to the present invention, in front of the fluorescent display unit,
Since it is configured to provide a plate-shaped accelerating anode having a window hole that transmits while accelerating the unfocused beam from the cathode, it is possible to prevent the unfocused beam from concentrating on a part of the accelerating anode, Therefore, the irradiation efficiency of the unfocused beam on the phosphor screen can be significantly improved, and as a result, an excellent image can be displayed on the large-screen display device.

[Brief description of drawings]

1 is a cross-sectional view of a light source display tube according to an embodiment of the present invention, FIG. 2 is a plan view of a conventional light source display tube, and FIG. 3 is a cross-sectional view taken along the line III-III of FIG. FIG. 4 is an exploded perspective view of a part thereof. 1 is a vacuum envelope, 2 is a front panel, 3 is a back plate, 4 is a cylindrical side plate, 5 is a fluorescent display part, 5G, 5R and 5B are fluorescent screens, 21 is an accelerating anode, and 22 is a window hole. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Zenichiro Hara 6-14 Maruo-cho, Nagasaki-shi, Nagasaki Mitsubishi Electric Corporation Nagasaki Works (72) Inventor Nobuo Terasaki 6-14 Maruo-cho, Nagasaki-shi, Nagasaki Mitsubishi (72) Inventor Yuji Kamogawa 700 Wada, Ueno-cho, Ise-shi, Mie 700 Wada, Ise Electronics Industry Co., Ltd. (72) Kazunori Tatsuda 700, Wada, Ueno-cho, Ise-shi, Mie Ise Electronics Industry Incorporated (56) References JP 62-10849 (JP, A) JP 56-9961 (JP, A)

Claims (1)

[Claims] 1. A vacuum envelope in which a front panel is attached to the front surface of a tubular side plate and a back panel is attached to the back surface of the tubular side plate in an airtight manner, and fluorescent light is formed by arranging fluorescent surfaces in a matrix on the inner surface of the front panel. In a light source display tube having a display unit and an accelerating anode that is arranged around each of the fluorescent screens and accelerates a non-focused beam that causes the fluorescent screens to emit light, the structure of the accelerating anode is the fluorescent display unit. A flat shadow mask plate provided with a window hole in front of each of them and a window hole through which the non-focused beam is transmitted so as to face each of the fluorescent screens of the fluorescent display unit. Display tube.