JP2956002B2 - Fluorescent display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent display device constituting a large-screen display device used in, for example, a stadium, and more particularly to an electrode structure of a plate-like shield electrode for controlling the luminance of a light emitting pixel. is there.

[0002]

2. Description of the Related Art FIG. 3 is an exploded perspective view showing the structure of this kind of fluorescent display device, in which one cathode is arranged corresponding to two pixels. In addition, a cathode may be arranged orthogonal to each pair of control electrodes, and one cathode may correspond to two pixels. In the figure, 1a is a glass display unit having phosphor pixels 9 formed by applying a phosphor paint, 1b is a frame-shaped glass spacer, 1c is a substrate on which a control electrode is disposed, The display unit 1a, the spacer 1b, and the substrate 1c constitute a unit main body 1 as a vacuum container.

In FIG. 1, reference numeral 2 denotes a linear cathode formed on a substrate 1c, 3 denotes a scanning electrode as a first control electrode, 4 denotes a data electrode as a second control electrode,
These scanning electrodes 3 and data electrodes 4 are arranged as shown in FIG. Wirings 5 and 6 electrically connect the scanning electrodes 3 and the data electrodes 4 in the row direction or the column direction. Reference numeral 7 denotes a flat plate shield electrode in which an opening 8 corresponding to the phosphor pixel 9 is formed, and reference numeral 10 denotes an exhaust unit.

[0004] Incidentally, the lead portions of S ₁ to S ₄ scanning electrodes 3 in the row direction is connected in common in Fig. 4, D ₁ to D ₄
Is a lead portion of the data electrode 4 commonly connected in the column direction. FIG. 5 shows timings of signals applied to these lead portions S _{1 to} S ₄ and D _{1 to} D ₄ . FIG. 6 shows the relationship between S _{1 to} S ₄ and D _{1 to} D ₄ and pixels P _{11 to} P ₄₄ .

In such a configuration, the thermoelectrons emitted from the cathode 2 behave in accordance with the combination of the potentials of the scanning electrode 3 and the data electrode 4. The behavior of the thermoelectrons will be described with reference to FIGS.

(1) The scanning electrodes 3 (for example, the lead-out portions S _{1 of the} scanning electrodes) connected in the row direction and the data electrodes 4 (for example, the lead-out portions D of the data electrodes) connected in the column direction.
₁ ) are both at a positive potential with respect to the cathode 2 and the other scanning electrode 3 (for example, the lead portion S _{2 of the} scanning electrode) is at a negative potential.
7A are deflected by the potential of the scanning electrode 3 as shown by reference numerals in FIG. 7A, pass through a predetermined opening 8 and reach the display section 1a serving as an anode, and the fluorescent pixel 9 (For example, the pixel P _{11 in} FIG. 6) is caused to emit light.

(2) When the scanning electrode 3 has a positive potential and the data electrode 4 has a negative potential, the potential near the cathode becomes negative due to the negative potential of the data electrode 4 closer to the cathode 2 than the scanning electrode 3. Thus, emission of thermoelectrons is suppressed (FIG. 7B).

(3) When the scanning electrode 3 (for example, the lead portion S _{2 of the} scanning electrode) has a negative potential and the data electrode 4 has a positive potential, there are the following two cases. (A) When the other scan electrode (the lead-out portion S _{1 of the} scan electrode sandwiching the data electrode 4 with respect to the scan electrode 3) is positive, thermions emitted from the cathode 2 emit the other scan electrode. The fluorescent pixel 9 is deflected to the side (for example, FIG.
The pixel P ₂₁ ) does not emit light (a in FIG. 7A). (B) When the other scan electrode is also at a negative potential (for example, the relationship between the lead portion S ₃ of the scan electrode and the lead portion S ₄ of the scan electrode in the figure), the potential of the data electrode 4 is positive, Since the area of the electrode 4 is smaller than the area of the scanning electrode 3, the scanning electrodes 3 on both sides of the data electrode become negative near the cathode due to the influence of the negative potential, the emission of thermoelectrons is suppressed, and the phosphor pixels 9 emit light. No (b in FIG. 7A).

(4) When both the scan electrode 3 and the data electrode 4 are at a negative potential (the lead portion S _{3 of} the scan electrode, the lead portion S ₄ of the scan electrode and the data electrode 4 are negative (FIG. 7B)
)), The potential near the cathode becomes negative, the emission of thermoelectrons is suppressed, and the phosphor pixels 9 do not emit light.
Therefore, the phosphor pixel 9 located at the boundary between the scanning electrode 3 to which the positive potential is applied and the data electrode 4 to which the positive potential is applied emits light.

[0010] In FIG. 6, for example, signal to the scan electrode lead portion S ₁ is applied, the selected pixel P ₁₁ to P ₁₄ is the data one of these or all through data electrode lead portions D ₁ to D ₄ Light is emitted according to the potential applied to the electrode 4. Since signals are sequentially applied to the scan electrode lead portions S _{1 to} S ₄ , an arbitrary display can be obtained by giving an arbitrary signal pattern to the data electrode lead portions D _{1 to} D ₄ .

[0011]

However, when a large-screen display device is constructed, a large number of such fluorescent display devices are arranged, so that the external lead-out electrodes 30 provided on the substrate 1c do not come into contact with each other. As shown in (1), the spacers 1b of the unit main body 1 are tapered so as to secure a space between the substrates 1c of the adjacent unit main bodies 1. For this reason, in the peripheral portion on the lead lead-out side, the positional relationship between the opening 8 of the cathode 2 or the flat plate shield electrode 7 and the fluorescent pixel 9 of the anode is shifted by an amount corresponding to the taper of the spacer 1b. However, there is a problem in that the positions where the thermal electrons collide are shifted, and each pixel does not emit light with uniform brightness, resulting in a display with noticeable variations.

[0012] As a solution to such a problem,
The deviation of the corresponding positional relationship between the phosphor pixel 9 and the opening 8 of the flat plate shield electrode 7 due to the taper of the spacer 1b is corrected by making the peripheral portion of the flat plate shield electrode 7 tapered. There has been proposed a fluorescent display device in which the luminance of each phosphor pixel 9 is made uniform (Japanese Patent Application No. 2-244533).

However, when the peripheral portion of the flat plate shield electrode is tapered, the distance between the cathode and the opening of the flat plate shield electrode differs between the central portion and the peripheral portion. There is a problem that a difference occurs in the amount of traveling electrons, the amount of electrons emitted from the opening in the peripheral portion increases, and pixels in the peripheral portion become brighter than other pixels. Further, when the pixel arrangement becomes higher in density, it is necessary to perform the above-described position correction not only on one row around but also on a plurality of surrounding rows. In this case, there is a problem that the phenomenon that surrounding pixels become brighter is further emphasized.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to prevent the non-uniformity of the luminance due to the variation of the electron collision position with respect to each pixel, and to improve the display quality. It is another object of the present invention to provide a fluorescent display device capable of further improving the above.

[0015]

In order to achieve the above object, a fluorescent display device according to the present invention is provided with a step portion at a peripheral portion which is continuous with a central portion of a plate-like shield electrode, and an inclined portion of the step portion is provided. Is provided with an opening.

[0016]

In the plate-shaped shield electrode according to the present invention, the distance between the opening and the cathode is substantially equal between the opening and the peripheral portion, and the displacement of the corresponding positional relationship between the phosphor pixel and the opening is corrected. .

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an enlarged sectional view of a main part showing a configuration of a fluorescent display device according to an embodiment of the present invention. In the same drawing, a plate-shaped shield electrode 7A arranged opposite to a cathode 2 formed on a substrate 1c has a flat portion of a central portion 7a in a peripheral portion 7b including a lead extraction side opening 8 surrounding the central portion 7a. a protrusion 7c projecting toward the upper direction from the stepped portion ₇₁ formed from an inclined portion 7d which is inclined toward the lower direction and continuous with the protruding portion 7c is formed integrally, the central portion 7a in the inclined portion 7d of the step portion 7 ₁
Distance D approximately equal to the distance of the opening 8 from the cathode 2
And the opening 8 is formed.

In such a configuration, the distance D between the cathode 2 and the opening 8 of the plate-shaped shield electrode 7A is substantially the same between the central portion 7a and the peripheral portion 7b.
The deviation of the corresponding positional relationship between the phosphor pixel 9 and the opening 8 is corrected while the amount of electrons emitted from the pixel is uniform, and the amount of thermal electrons colliding with each phosphor pixel 9 is made uniform. As a result, substantially the same brightness without variation in the emission luminance of each phosphor pixel 9 can be obtained.

FIG. 2 is an enlarged sectional view of a main part showing a structure of another embodiment of the fluorescent display device according to the present invention (when the phosphor pixels 9 are arranged in an 8.times.8 array). Are denoted by the same reference numerals. In this figure, the difference from FIG. 1 is that a central portion 7
the step portion of the two-stage consisting of a first step portion ₇₁ and the second stepped portion 7 ₂ which in succession a is integrally formed, the first of these
The step portion ₇₁ and the second stepped portion 7 ₂ each protrusion 7c ₁ 7C ₂ and the inclined portion 7 _d1, 7 _d2 is formed, these inclined portions 7 _d1, 7 _d2 each opening 8 Is formed.

The plate-shaped shield electrode 7 thus configured
In B, even when the position correction for the shift of the corresponding positional relationship is performed over a plurality of columns of the openings 8 facing the phosphor pixels 9, the position correction can be performed while the amount of electrons is uniform.

[0021]

As described above, according to the present invention,
A fluorescent display with excellent display quality without luminance variations, because the positional relationship between the phosphor pixels and the plate-shaped shield electrode opening can be corrected while keeping the distance between the cathode and the plate-shaped shield electrode constant. It has an extremely excellent effect that a device can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a fluorescent display device according to the present invention.

FIG. 2 is a diagram showing a configuration of another embodiment of the fluorescent display device according to the present invention.

FIG. 3 is an exploded perspective view showing a configuration of a conventional fluorescent display device.

FIG. 4 is a plan view showing a substrate in a conventional fluorescent display device.

FIG. 5 is a diagram showing a signal time chart in the fluorescent display device.

FIG. 6 is a plan view of the fluorescent display device as viewed from the front side.

FIG. 7 is a diagram for explaining the behavior of thermoelectrons in the fluorescent display device.

FIG. 8 is a diagram illustrating a problem of a conventional display unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Unit main body 1a Display part 1b Spacer 1c Substrate 2 Linear cathode 3 Scanning electrode 4 Data electrode 7A Plate-shaped shield electrode 7B Plate-shaped shield electrode 7a Central part 7b Peripheral part 7c Projecting part 7c ₁ projecting part 7c ₂ projecting part 7d inclined part 7 _d1 inclined part 7 _d2 inclined part 7 ₁ first step part 7 ₂ second step part 8 opening 9 phosphor pixel 10 exhaust part 30 lead lead external electrode S ₁ lead part of scan electrode S ₂ lead of scan electrode Part S ₃ Leader of scanning electrode S ₄ Leader of scanning electrode D ₁ Leader of data electrode D ₂ Leader of data electrode D ₃ Leader of data electrode D ₄ Leader of data electrode

Continued on the front page (72) Inventor Zenichiro Hara 6-14 Maruo-cho, Nagasaki-shi, Nagasaki Mitsubishi Electric Corporation Inside Nagasaki Works (72) Inventor Kosaburo Shibayama 6-14 Maru-cho, Nagasaki-shi, Nagasaki Mitsubishi Electric Corporation In Nagasaki Works (56) References JP-A-64-995 (JP, A) JP-A-1-100854 (JP, A) JP-A-4-53990 (JP, A) JP-A-1-246751 (JP, A A) JP-A-4-355035 (JP, A) JP-A-1-253147 (JP, A) JP-A-1-253150 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) ) H01J 31/08-31/24 H01J 1/30 H01J 9/02

Claims (1)

(57) [Claims] A cathode disposed on a substrate in such a manner that each pixel or a plurality of pixels is disposed on a substrate in a vacuum vessel having a display section in which pixels made of a phosphor are arranged in a matrix. A fluorescent display device including a plate-shaped shield electrode having an opening formed at a position corresponding to each of the pixels between the display unit and the substrate and a control electrode for controlling a flow of thermoelectrons emitted by the cathode, Providing a stepped portion having an inclined portion protruding in the pixel side direction and a peripheral portion continuous with a central portion of the plate-shaped shield electrode,
The inclined portion is provided with an opening on the side of the peripheral portion, the distance between each opening of the plate-shaped shield electrode and the cathode is kept constant, and the positional relationship between the pixel and the opening is shifted. A fluorescent display device, wherein