JPH0640483B2 - Fluorescent display device - Google Patents

Description

Detailed Description of the Invention

[Industrial applications]

The present invention mainly relates to a fluorescent display element that forms a pixel in a large color display device or the like.

[Prior art]

As a fluorescent display element forming a pixel of a color display device, as shown in FIG. 5, a plurality of light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ forming one pixel are connected to form one discharge space. A structure in which a common cathode 22 is provided in this discharge space has been proposed. In this fluorescent display element, a light source tube 10 is provided, and the inner space of the light source tube 10 is partitioned by a partition wall 13 to form, for example, four light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ . Different emission colors (here, 1R is red, 1G ₁ and 1G ₂ are green, and 1G ₁ and 1G ₂ are green on the inner peripheral surface of each light emitting chamber 1R, 1G ₁ , 1B, 1G ₂
The phosphor of (B is shown later) is applied. Also,
The light source tube 10 is provided in each of the light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ .
The communication holes 2R, 2G ₁ , 2B, and
2G ₂ is formed, and anodes 3R, 3G ₁ and 3 are formed elsewhere.
B, 3G ₂ are arranged. One surface of the light source tube 10 (5th
The upper surface in the figure (b) is formed of a light-transmitting material such as glass, and the other parts of the light source tube 10 are formed of a non-light-transmitting material such as ceramic having a relatively high reflectance for visible light. On the lower surface of the light source tube 10 in FIG. 5 (b), the communication holes 2R, 2G ₁ ,
The bulb 20 is sealed so as to straddle 2B and 2G ₂ , and the bulb 20 is provided with a common cathode 22 held by a stem 21. As described above, the internal space between the light source tube 10 and the bulb 20 communicates with each other through the communication holes 2R, 2G ₁ , 2B, 2G ₂ to form one airtight discharge space. A discharge gas composed of mercury and an inert gas such as argon is enclosed in the space. When the desired anodes 3R, 3G ₁ , 3B, 3G ₂ and the common cathode 22 are discharged, the anodes 3R, 3G involved in the discharge are discharged.
_1, 3B, light emitting chamber 1R, 1G _1, 1B corresponding to 3G _2, 1G ₂
Emits light and can emit light in a desired color. Since the fluorescent display element formed as described above forms a pixel of the color display device, the common cathode 22 is always in a state capable of emitting electrons so that it can be turned on at any dimming stage at any time. There is a need. That is, the common cathode 22 is always preheated.

[Problems to be Solved by the Invention]

By the way, since it is used as a pixel of a color display device, the light emitting area of the fluorescent display element is relatively small. Therefore, power consumption during lighting is relatively small. On the other hand, the preheating power supplied to the common cathode 22 is substantially constant regardless of the size of the fluorescent display element. For example, assuming that all the light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ are made to emit light uniformly and white lighting is performed, the relationship between the light emission luminance and the power consumption is examined, and the result is as shown in FIG. According to FIG. 6, ² W is required to obtain a brightness of 5000 cd / m ² , and 1.5 W at 2500 cd / m ² when no light is emitted.
Even at (0 cd / m ² ), there is 1 W of power consumption. That is, since 1 W is consumed as the preheating power for the common cathode 22,
The power consumption due to the preheating of the common cathode 22 is 5% of the total power consumption.
There is a problem that the luminous efficiency reaches 0% or more, and the luminous efficiency is poor, which is equivalent to the power consumption. The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to provide a fluorescent display device having improved luminous efficiency by reducing the power consumption per unit area consumed by preheating power.

[Means for Solving the Problems]

In the present invention, in order to achieve the above object, the light emitting surface of the light source tube is divided into a plurality of compartments each including the same number of light emitting chambers, and each compartment has the same emission color configuration. Each of them is composed of a luminous chamber of a plurality of colors.

[Action]

According to the above configuration, the constitutional unit in which one common cathode is provided in the conventional configuration is defined as one section, and one common cathode is provided for a plurality of sections. Therefore, preheating with the common cathode per unit area is performed. Electric power is reduced as compared with the conventional one, and as a result, luminous efficiency is increased.

[Embodiment 1] As shown in FIG. 1, basically, four light source tubes 10 described in the section "Prior Art" are combined to form one light source tube 10. The body 10 is provided with one valve 20. As shown in FIG. 1, the light source tube body 10 is formed by a light emitter 11 formed in a low-angle cylindrical shape having an upper surface opening, and a translucent plate 12 sealing the upper surface of the light emitter 11. The light emitter 11 is formed of a non-translucent material such as ceramic having a relatively high reflectance for visible light, and the translucent plate 12 is formed of a translucent material such as glass. The internal space of the light source tube body 10 is divided into four sections A to D having substantially the same shape by the partition walls 13a and 13b. Each section A-D
Each of them is formed to have substantially the same size as the light source tube body 10 described in the section “Prior Art”. The inner space of each of the sections A to D is further divided by the partition wall 13c to form four light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ . After all, 16 light emitting chambers 1R, 1G ₁ , 1 are provided for one light source tube 10.
B, 1G ₂ is formed. Each luminous chamber 1R, 1G ₁ , 1B, 1G
_A phosphor is applied to each of the inner peripheral surfaces of ₂ . That is, in the light emitting chamber 1R, a red phosphor (for example, Y ₂ O ₃ : E
u), the light emitting chambers 1G ₁ and 1G ₂ have green phosphors (for example,
CeMgAl ₁₁ O ₁₉ : Tb) and the luminous chamber 1B are coated with a blue phosphor (for example, BaMg ₂ Al ₁₆ O ₂₇ : Eu). Here, in each of the sections A to D, the light emitting chambers 1R, 1G ₁ , 1 rotate counterclockwise from the upper right corner.
B and 1G ₂ are arranged in this order. Each light emitting room 1R, 1
In G ₁ , 1B, 1G ₂ , communication holes 2R, 2G ₁ , 2B, 2G ₂ are formed in _one place near the centers of the sections A to D, and anodes 3R, 3G ₁ , 3B, 3G ₂ are formed in other places. Is provided. Further, a partition wall 4 is formed in each of the light emitting chambers 1R, 1G ₁ , 1B, 1G ₂ , and the communication holes 2R, 2G ₁ , 2B, 2G ₂ are formed.
The paths (paths) from the anodes 3R, 3G ₁ , 3B, 3G ₂ to the anodes are bent as long as possible. The upper end of the bulb 20 is sealed to the lower surface of the light source tube 10 in FIGS. 1 (b) and 1 (c). The bulb 20 is made of glass, and a common cathode 22 supported by a stem 21 is provided inside. The upper portion of the valve 20 is branched into four branch pipes 24, the upper ends of the branch pipes 24 are open, and communication holes 2R, formed in the central portions of the sections A to D,
The light source tube 10 is sealed so as to cover 2G ₁ , 2B and 2G ₂ . An exhaust pipe 23 is drawn out from the lower surface of the valve 20. As described above, the airtight discharge space surrounded by the light source tube 10 and the bulb 20 is formed, and the discharge gas in which the inert gas such as argon and the mercury are mixed is formed in the discharge space. Enclosed. Here, the light emitter 1 of the light source tube body 10
1, the translucent plate 12, the light source tube 10, the bulb 20 and the like are sealed with a glass frit. Now, assuming that the common cathode 22 is discharged between the anode 3R provided in the light emitting chamber 1R of the compartment A and the common cathode 22,
Since the electrons emitted from the light source pass through the path of the common cathode 22 → the branch tube 24 → the communication hole 2R of the compartment A → the light emitting chamber 1R of the compartment A → the anode 3R, red light is emitted from the light emitting chamber 1R. . According to the above configuration, assuming that one section A to D has the same area as that of the conventional fluorescent display element, the number of common cathodes 22 per unit area becomes 1/4, and as a result, per unit area. Also, the preheating power to the common cathode 22 is reduced to 1/4 in theory. That is, as shown by the solid line in FIG. 2, the power consumption per unit area is significantly reduced as compared with the conventional configuration shown by the broken line, and white for one pixel (one section) of the conventional configuration is obtained. The power consumption required to obtain 5000 cd / m ² when turned on is 1.3
W (Lamp efficiency improved by 54% compared to the conventional configuration), 2
0.8 W at 500 cd / m ² (88% improvement in lamp efficiency),
At 0 cd / m ² , it is 0.3 W (lamp efficiency is improved by 230%), which shows that the lamp efficiency is significantly improved. Also,
In the above embodiment, the light source tube body 10 is provided with four sections A to D. However, if the number of branch tubes 24 is increased, a larger number of sections can be provided to further reduce the preheating current per unit area. It is possible.

Second Embodiment In the first embodiment, rectangular luminous chambers 1R, 1G ₁ , 1B, 1G ₂ are formed in the respective compartments A to D, and the luminous chambers 1R, 1G ₁ ,
The communication holes 2R, 2G ₁ , 2B, 2G ₂ are formed in 1B and 1G ₂ , respectively, but in this embodiment, as shown in FIG. 3, one communication hole 2 is provided in each of the sections A to D. A partition 13d is formed on each of the partitions A to D to form three light emitting chambers 1R, 1G, 1B respectively. That is, each section A ~
In D, a communication hole 2 is formed near the center of the light source tube body 10,
Two partition walls 13d are formed radially about the communication hole 2 as a center. Therefore, in each of the sections A to D, the communication hole 2 is shared by all the light emitting chambers 1R, 1G, 1B. In each of the sections A to D, the light emitting chamber 1 is rotated clockwise.
R, 1G, 1B are arranged in this order. Each luminous chamber 1
In R, 1G, 1B, the anode 3R,
3G and 3B are provided. On the other hand, the common cathode 22 is provided in the bulb 20, the upper surface of the bulb 20 is open, and each of the sections A to
The light source tube body 10 is sealed so as to cover a total of four communication holes 2 provided in D respectively. Here, since the communication holes 2 are concentrated in the central portion of the light source tube body 10, it is not necessary to provide the bulb 20 with the branch tube 24 as in the first embodiment. That is, a structure similar to that of the end portion of the straight tube fluorescent lamp can be obtained, and the parts can be easily shared. With the above configuration, the power consumption of one pixel (one section) of the conventional configuration during white lighting was measured, and the result shown by the solid line in FIG. 4 could be obtained. That is, 5000 cd / m ²
The power consumption required to obtain the above is 1.6 W (2 W as shown by the broken line in the case of the conventional configuration), and the lamp efficiency is improved by 25%. Further, it is 0.95W for 2500 cd / m ² , and the lamp efficiency is improved by 58%, and 0.3 W for 0 cd / m ^2.
The lamp efficiency was improved by 230%. As described above, the lamp efficiency could be significantly improved. In each of the above embodiments, the light source tube 1 is divided into four sections A to D, but the number of sections is not limited to this.
Further, a large number may be formed.

【The invention's effect】

According to the present invention, as described above, the light emitting surface of the light source tube is divided into a plurality of sections each including the same number of light emitting chambers, and each section is configured to have the same light emission color configuration, and each section has a plurality of colors. In the conventional configuration, one common cathode is provided in one unit, and one common cathode is provided in a plurality of units. There is an advantage that the preheating power to the common cathode is reduced as compared with the conventional one, and as a result, the luminous efficiency is increased.

[Brief description of drawings]

1 (a), (b) and (c) are respectively a front view of the first embodiment of the present invention, a sectional view taken along line XX in FIG. 1 (a), a sectional view taken along line YY in FIG. 1 (a), 2 is an explanatory view of the same operation as above, FIGS. 3 (a) and 3 (b) are front views showing a second embodiment of the present invention, a sectional view taken along line XX in FIG. 5A is a front view showing a conventional example, FIG. 5A is a sectional view taken along line XX in FIG. 5A, and FIG. 1R, 1G ₁ , 1B, 1G ₂ ... Luminous chamber, 3R, 3G ₁ , 3B,
3G ₂ …… Anode, 10 …… Light source tube, 20 …… Valve,
22 ... Common cathode, A to D ... Compartments.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Hiramatsu 1048, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd. (72) Noriyuki Taguchi, 1048, Kadoma, Kadoma City, Osaka Matsushita Electric Works, Ltd.

Claims (1)

[Claims] 1. A light source tube body having a plurality of light emitting chambers, each having an inner peripheral surface coated with a phosphor, provided on the light emitting surface, and a light source tube body for forming a discharge space communicating with each light emitting chamber. An airtightly coupled bulb, a plurality of anodes respectively disposed in the light emitting chambers, and a common cathode disposed in the bulb are provided, and a discharge gas is enclosed in the discharge space. In a fluorescent display element in which a phosphor in a light emitting chamber in which the anode in which discharge occurs is disposed emits light when a voltage that causes discharge is applied between a desired anode and a common cathode, light emission of a light source tube body. The surface is divided into a plurality of compartments each including the same number of light-emission chambers, and each compartment is composed of a plurality of light-emission chambers so that the light-emission colors of the respective compartments are the same. Fluorescent display device.