JPH06181039A - Light emitting element - Google Patents

Abstract

PURPOSE:To prevent intensity of emitted light from being lowered and also to increase the grade of display by forming electrode wiring between a data electrode and a scanning electrode through an insulating layer directly under the data electrode or the scanning electrode so as to prevent a control electric field from being affected by the electric field of the electrode wiring. CONSTITUTION:Two phosphor picture element 9 hold one piece of linear cathode 2 in common, electrode wiring 5, 6 is formed on a substrate 1c through an insulating layer 11 directly under a scanning electrode 3 and a data electrode 4 and are connected to a part for leading out each electrode. Thereby, even when negative potential is applied to the wiring 6 of the electrode 4, the negative electric field of the wiring 6 is prevented from entering through the layer 11 between the electrodes 2, 4 so that the negative electric field of the wiring 6 does not have an influence upon the control electric field of an electrode 3 to which position potential is applied. As a result, the lowering of potential in the periphery of the cathode 2 is eliminated to output a predetermined amount of thermoelectrons emitted from the cathode 2 and to provide the desired brightness of emitted light. Thereby, the lowering of the brightness of emitted light can be prevented and the high grade of display can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting element constituting a large-screen display device used in, for example, a stadium, and more particularly to an electrode wiring structure of a control electrode section for controlling light emission of a display section. .

[0002]

2. Description of the Related Art FIG. 2 is an exploded perspective view showing the structure of, for example, a fluorescent display device as a light emitting element of this type.
The case where the respective cathodes are arranged correspondingly is shown. In addition, a cathode may be arranged orthogonal to each pair of control electrodes, and two cathodes may correspond to one cathode. In the figure, 1a is a glass display unit having phosphor pixels 9 formed by applying a phosphor coating, 1b is a frame-shaped glass spacer, 1c is a substrate on which control electrodes are arranged, The display unit 1a, the spacer 1b and the substrate 1c constitute a unit body 1 which is a vacuum container.

In FIG. 2, 2 is a linear cathode formed on the substrate 1c, 3 is a scanning electrode, 4 is a data electrode, and these scanning electrodes 3 and 4 are shown in FIG.
It is arranged as shown in. Reference numerals 5 and 6 are electrode wirings for electrically connecting the scan electrodes 3 and the data electrodes 4 in the row direction or the column direction, respectively. Reference numeral 7 is a plate-shaped shield electrode having an electron passage portion 8 formed of an opening corresponding to the phosphor pixel 9, and 10 is an exhaust portion.

Further, in FIG. 3, eight data electrodes 4 for controlling the emission of thermoelectrons from the cathode 2 are formed in 2 rows and 4 columns in a portion of the surface of the substrate 1c facing each cathode 2. Each data electrode 4 controls the emission of thermoelectrons from the corresponding cathode 2 by applying a positive or negative potential to the potential of the cathode 2. Also,
At both ends of each data electrode 4 in the column direction on the surface of the substrate 1c, the traveling direction of thermoelectrons emitted from the cathode 2 is controlled 1
Six scan electrodes 3 are formed in a matrix over 4 rows and 4 columns. The data electrode 4 has a smaller surface area than the scanning electrode 3.

Further, the eight data electrodes 4 are arranged in two in the column direction.
Each of them is wired by four electrode wirings 6 arranged in the column direction, and further, 16 scanning electrodes 3 are arranged in the row direction such that four scanning electrodes 3 are orthogonal to the electrode wirings 6, that is, arranged in the row direction. The four electrode wirings 5 are connected to each other. The electrode wiring 5 and the electrode wiring 6 are wired via an insulating layer so as not to contact each other. The scan electrodes 3, data electrodes 4, electrode wirings 5 and electrode wirings 6 are formed by printing on the surface of the substrate 1c.

Incidentally, S _{1 to} S ₄ in FIG. 3 are lead-out portions of the scanning electrodes 3 which are commonly connected in the row direction, and D _{1 to} D _{4 are shown.}
Is the lead-out portion of the data electrode 4 connected in common in the column direction, the timing of these lead portions S ₁ to S _4, D ₁ signal which is applied to the to D ₄ shown in FIG. 4, these lead portions FIG. 5 shows the relationship between S _{1 to} S ₄ , D _{1 to} D ₄ and the pixels P _{11 to} P ₄₄ .

In such a structure, 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 this thermoelectron will be described with reference to FIGS.

(1) The scanning electrodes 3 connected in the row direction (for example, the extraction portion S _{1 of the} scanning electrode) and the data electrodes 4 connected in the column direction (for example, the extraction portion D of the data electrode)
₁ ) both have a positive potential with respect to the cathode 2 and the other scanning electrode 3 (for example, the scanning electrode lead-out portion S ₂ ) has a negative potential, the positive potential of the data electrode 4 causes the cathode 2
6A, the thermoelectrons emitted from are deflected by the potential of the scanning electrode 3, pass through a predetermined electron passage portion 8 and reach the display portion 1a which is an anode, and the phosphor pixel 9 (for example, the pixel P _{11 in} FIG. 5) is caused to emit light.

(2) When the scan 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 which is closer to the cathode 2 than the scan electrode 3. Therefore, the emission of thermoelectrons is suppressed (in FIG. 6B).

(3) When the scan electrode 3 (for example, the lead-out portion S _{2 of the} scan electrode) has a negative potential and the data electrode 4 has a positive potential, there are the following two cases. (A) When the other scanning electrode (the lead-out portion S _{1 of the} scanning electrode sandwiching the data electrode 4 with respect to the scanning electrode 3) is positive, the thermoelectrons emitted from the cathode 2 generate the other scanning electrode. The phosphor pixel 9 is deflected to the side (for example, as shown in FIG.
Pixel P ₂₁ ) does not emit light (a in FIG. 6A). (B) When the other scan electrode is also negative potential (for example, the relationship between the scan electrode lead-out portion S ₃ and the scan electrode lead-out portion S _{4 in} the drawing), the potential of the data electrode 4 is positive, but the data electrode 4 is 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 in the vicinity of the cathode 2 due to the influence of a negative potential, and the emission of thermoelectrons is suppressed, so that the phosphor pixel 9 is formed. Does not emit light (b in FIG. 6A).

(4) When both the scan electrode 3 and the data electrode 4 have a negative potential (the scan electrode lead-out portion S ₃ , the scan electrode lead-out portion S ₄ and the data electrode 4 are negative (FIG. 6B).
)), The potential near the cathode 2 becomes negative,
The emission of thermoelectrons is suppressed, and the phosphor pixel 9 does 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.

In FIG. 7, for example, when a signal is applied to the scan electrode lead-out portion S ₁ , the pixels P _{11 to} P ₁₄ are selected, and one or all of these pixels are read through the data electrode lead-out portions D _{1 to} D _4. It emits light according to the potential applied to the electrode 4. Since signals are sequentially applied to the scan electrode lead-out portions S _{1 to} S ₄ , an arbitrary display can be obtained by giving an arbitrary signal pattern to the data electrode lead-out portions D _{1 to} D ₄ at that time. A fluorescent display device of this type is disclosed in, for example, Japanese Patent Laid-Open No. 64-995.

[0013]

However, in the conventional fluorescent display device having such a configuration, a plurality of electrode wirings 5 and 6 of the scanning electrodes 3 and the data electrodes 4 are formed on the surface of the substrate 1c. Insulating layer 11a of
11b are separated from each other, but a large number of electrode wirings are required as apparent from FIG. 3, and therefore, as shown in the enlarged cross-sectional view of FIG. 7, the lower part of the gap between the scanning electrode 3 and the data electrode 4 is formed. Was also formed. Therefore, when a negative voltage is applied to some of the electrode wirings, a negative electric field enters directly above the electrode wirings via the insulating layer 11, and the negative electric field is applied with a positive potential. There is a problem that the positive electric field is weakened by acting on the control electric field, and as a result, the potential of the peripheral portion of the cathode 2 is decreased, the amount of thermoelectrons emitted from the cathode 2 is decreased, and the emission brightness is decreased.

Therefore, the present invention has been made to solve the above-mentioned conventional problems, and its purpose is to reduce the influence of the control electric field in the peripheral portion of the cathode due to the influence of the electric field of the electrode wiring, and to reduce the emission brightness. An object of the present invention is to provide a light emitting device that can prevent deterioration and improve display quality.

[0015]

In order to achieve the above object, the light emitting device according to the present invention is configured such that the electrode wiring of the data electrode and the scan electrode is formed directly below the data electrode or the scan electrode with an insulating layer therebetween. It is the one.

[0016]

In the present invention, since the electrode wiring is arranged immediately below the data electrode or the scanning electrode, even if a negative voltage is applied to the electrode wiring, the data electrode and the scanning electrode, the data electrode, or the scanning electrode is connected. A negative electric field is prevented from entering through the insulating layer in the gap.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is an enlarged cross-sectional view of an essential part for explaining the configuration of an embodiment of a light emitting device according to the present invention, and the same parts as those in the above-mentioned drawings are designated by the same reference numerals. It should be noted that this embodiment shows a configuration in which two phosphor pixels 9 share one cathode 2. In the figure, the electrode wiring 5 is formed and arranged on the substrate 1c directly below the control electrode 3 via the insulating layer 11 and is connected to the scanning electrode lead-out portion S _{1 (} not shown). Similarly, directly below the data electrode 4, the electrode wiring 6 is formed on the substrate 1c via the insulating layer 11.
Are formed and arranged, and are connected to the data electrode lead-out portion D _{1 (} not shown).

According to this structure, a negative potential is applied to the electrode wiring 6 of the data electrode 4, for example, by forming and arranging the electrode wiring 5 and the electrode wiring 6 immediately below the scanning electrode 3 and the data electrode 4, respectively. Even the scan electrode 2
The negative electric field due to the electrode wiring 6 does not enter through the insulating layer 11 in the gap between the data electrode 4 and the data electrode 4, and the negative electric field acts on the control electric field of the scanning electrode 3 to which the positive potential is applied. Since it does not affect the positive electric field, as a result, the potential of the peripheral portion of the cathode 2 does not decrease,
A predetermined amount of thermionic emission is output from the cathode 2 and a desired light emission brightness can be obtained.

In the above-described embodiments, the case where the electrode wiring 5 and the electrode wiring 6 are provided on the substrate 1c directly below the control electrode 3 and the data electrode 4 via the insulating layer 11 has been described. It goes without saying that the same effect as described above can be obtained even if it is provided between the single insulating layer 11a and the second insulating layer 11b.

Further, in the above-described embodiment, the case where the electrode wiring 5 and the electrode wiring 6 are arranged directly below the control electrode 3 and the data electrode 4 via the insulating layer 11 has been described, but the present invention is not limited to this. The present invention is not limited to this, and the electrode wiring 6 of the data electrode 4 may be arranged immediately below the control electrode 3, or the electrode wiring 5 of the control electrode 3 may be arranged immediately below the data electrode 4. Needless to say, the same effect as can be obtained.

[0021]

As described above, according to the present invention,
Since the electrode wiring of the data electrode and the scanning electrode is formed immediately below the data electrode or the scanning electrode with the insulating layer separated, the control electric field by the data electrode or the control electrode in the peripheral portion of the cathode is less likely to be affected by the electric field of the electrode wiring. Therefore, there is an extremely excellent effect that a decrease in light emission luminance can be prevented and a light emitting element with high display quality can be obtained.

[Brief description of drawings]

FIG. 1 is an enlarged plan view of an essential part showing the configuration of an embodiment of a light emitting device according to the present invention.

FIG. 2 is an exploded perspective view showing a configuration of a conventional fluorescent display device.

FIG. 3 is a plan view showing a substrate in a conventional fluorescent display device.

FIG. 4 is a diagram showing a signal time chart in the fluorescent display device.

FIG. 5 is a plan view of the fluorescent display device as viewed from the front side.

FIG. 6 is a diagram for explaining the behavior of thermoelectrons in the fluorescent display device.

FIG. 7 is a diagram illustrating a problem in a conventional fluorescent display device.

[Explanation of symbols]

1 unit body 1a display part 1b spacer 1c substrate 2 linear cathode 3 scanning electrode 4 data electrode 5 electrode wiring 6 electrode wiring 7 plate-shaped shield electrode 8 electron passage portion 9 phosphor pixel 10 exhaust portion S ₁ scanning electrode lead-out portion S ₂ Scan electrode lead-out portion S ₃ Scan electrode lead-out portion S ₄ Scan electrode lead-out portion D ₁ Data electrode lead-out portion D ₂ Data electrode lead-out portion D ₃ Data electrode lead-out portion D ₄ Data electrode lead-out portion 11 Insulation Layer 11a First insulating layer 11b Second insulating layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Zenichiro Hara 6-14 Maruo-cho, Nagasaki-shi, Nagasaki Mitsubishi Electric Corporation Nagasaki Works

Claims (1)

[Claims] 1. A display unit comprising a plurality of fluorescent display units, each of which is coated with a phosphor and emits light when a thermoelectron collides, arranged in a matrix of 2 m rows and n columns (m and n are natural numbers), and the display unit. A cathode that is arranged in m rows and n columns so as to correspond to one of the two fluorescent display portions at a position facing each other and that is linear in the row or column direction for emitting thermoelectrons; and the display portion and the cathode. A flat plate-shaped shield electrode having an opening corresponding to each fluorescent display section of the display section provided between the cathode and the cathode provided at a position opposite to the display section of the cathode corresponding to each cathode. Data electrodes of m rows and n columns for controlling thermoelectron emission and scan electrodes of 2m rows and n columns provided on both sides of the data electrodes in the column direction for controlling the traveling direction of thermoelectrons emitted from the cathode are provided. In the light emitting device, Light-emitting elements, characterized in that formed at the insulating layer just below the electrode wiring of the heater electrode and the scanning electrode and the data electrodes or scanning electrodes.