JPH06325697A - Color plasma display panel - Google Patents

Abstract

PURPOSE:To reduce the cost, and to facilitate the improvement for high display density by setting a product of a distance between a negative electrode and a positive electrode and the helium gas filling pressure within a specified range, and flowing the discharge current discharged from the negative electrode to the positive electrode through a conductive phosphor to obtain the light emission. CONSTITUTION:Plural negative electrodes 2 made of aluminum are arranged 3 in parallel with each other on a glass substrate 1, and plural linear positive electrodes 4 made of ITO film (transparent conductive film) are arranged in parallel with each other on a glass substrate in a manner of orthogonally crossing the negative electrodes 2. A conductive red light emitting phosphor 8, a conductive green light emitting phosphor 9, a conductive blue light emitting phosphor 10 for exciting low speed electron beams are formed over the whole surface of the positive electrodes 4. The inside of a discharge space 5 held by a spacer 7 is filled with He gas, of which filling pressure is set at a value for satisfying a condition that a product of a distance between the negative electrode and the positive electrode and the filling pressure is within a range of 95-140Torr.mm. Voltage at a discharge starting voltage or higher is applied between the desired negative electrode and the desired positive electrode to obtain the light emission of the concerned phosphor by the gas discharge in a discharge space on an intersection of that negative electrode 2 and that positive electrode 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color plasma display panel.

[0002]

2. Description of the Related Art In a conventional color plasma display panel, a plurality of linear cathodes 2 are arranged in parallel on a glass substrate 1 as shown in FIGS. A plurality of linear anodes 4 are arranged in parallel on the substrate 3 so as to be orthogonal to the cathode 2, and each intersection of the cathode 2 and the anode 4 has a dot matrix structure in which a discharge space 5 is formed. . Then, the glass substrate 3 and the anode 4
On the surface of each dot, R (red), G (green),
Although the phosphor 6 for UV excitation arranged in B (blue) is formed, since the phosphor 6 does not have conductivity, the anode 4 is prevented from being electrically insulated in order to prevent it from being electrically insulated. Four
The phosphor 6 is not formed in a part of the above, and a part of the anode 4 is exposed in the discharge space 5. In the discharge space 5 partitioned by the spacers 7 formed between the adjacent anodes 4, a gas mainly containing helium (He) mixed with several% of xenon (Xe) is enclosed.

In such a structure, when a voltage equal to or higher than the discharge start voltage is applied between the arbitrary cathode 2 and the positive electrode 4, a gas discharge is generated in an arbitrary discharge space 5 which is a three-dimensional intersection of both electrodes. Occurs. At this time, the electrons emitted from the cathode 2 collide with the Xe filled in the discharge space 5 to excite the Xe, and the excited Xe emits excitation energy as ultraviolet rays to the outside to return to the ground state. In this way X
By irradiating the phosphor 6 with the ultraviolet rays emitted from e, the phosphor 6 emits light by being excited by the ultraviolet rays.
In order to obtain a full-color display, R, G, B adjacent to each other
The method of controlling the voltage application time to the anode 4 corresponding to each display dot and combining the light emission of each color is adopted, but in these display dots, the ultraviolet rays generated in a certain display dot are fluorescence of the adjacent display dot. In order to prevent a malfunction called crosstalk in which the body is excited to emit light, each is partitioned by a spacer 7.

[0004]

However, in such a conventional color plasma display panel,
Since Xe is contained in the gas, the discharge start voltage and the discharge sustaining voltage become high, and the withstand voltage of the IC of the drive circuit must be increased accordingly, so the price of the IC becomes very high. There was a problem that the cost was high. This will be described in more detail with reference to FIG. FIG. 7 shows the discharge starting voltage and the discharge sustaining voltage and the gas pressure p when aluminum (Al) was used for the cathode and He or He—Xe (2%) was used for the enclosed gas.
It is a figure which respectively shows the relationship with the product (henceforth p * d product) of the distance d from a cathode to an anode. 7 (a),
In (b), when the curve A is He, the curve B is He-
This is the case of Xe (2%). As can be seen from FIGS. 7 (a) and 7 (b), in the gas mixed with Xe, the discharge start voltage and the discharge sustaining voltage are both 40 V in both p and d products as compared with the gas not mixed. It will be higher than that. In the conventional color plasma display panel,
In order to make the discharge start voltage as low as possible, the p · d product is set near 50 Torr · mm, but in this case as well, the discharge start voltage is 200 V or higher and the discharge sustaining voltage is 160
As the IC used in the drive circuit becomes 250 V or higher, the voltage for the writing circuit is 250 V or higher, and the voltage for the discharge maintaining circuit is 200 V or higher.
A high withstand voltage of V or more is required, which causes an increase in cost.

Further, in the conventional color plasma display panel, discharge light emission (negative glow) near the cathode, which is a source of ultraviolet rays, moves on the cathode and excites the fluorescent substance on the adjacent anode to cause erroneous light emission. In order to prevent this, the discharge space must be partitioned by the spacers 7, and these spacers increase the dot pitch, which is an obstacle to the realization of high display density.

[0006]

In a plasma display panel of the present invention, a gas is sealed between substrates having a cathode and an anode provided on the inner surface or between substrates having a cathode and an anode provided on the inner surface. In a plasma display panel in which a voltage is applied between the cathode and the anode to cause a gas discharge to excite a phosphor provided in a discharge space, the gas is helium, and the phosphor is low-speed. It consists of a conductive phosphor for electron beam excitation, this conductive phosphor is formed on the anode, the distance between the cathode and the anode, or, from the cathode of the discharge current to the anode The product of the path and the filling pressure of helium is selected in the range of 95 to 140 Torr · mm, and the discharge current emitted from the cathode flows into the anode through the conductive phosphor. By and to obtain a light emission of the conductive phosphor by electron beam excitation.

[0007]

According to the present invention, since helium is used as the filling gas, the discharge starting voltage and the discharge sustaining voltage can be lowered as compared with the conventional case. In addition, since the mean free path of electrons in helium is longer than in the past, the acceleration of electrons emitted from the cathode is large, and as a result,
Electrons having a high electron temperature can be made to flow into the phosphor, and the emission efficiency of the phosphor by electron beam excitation can be made equal to or higher than that in the case of ultraviolet excitation. At this time, only the phosphor into which the electrons have flown emits light, so that the electrons can flow into only the target anode.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an opposed discharge type color plasma display panel according to a first embodiment of the present invention will be described with reference to FIG.
Will be explained.

In FIGS. 1 (a) and 1 (b), a plurality of linear cathodes 2 made of aluminum (Al) having a thickness of 5 μm are juxtaposed in parallel on a glass substrate 1, and a glass facing each other is arranged. A plurality of linear anodes 4 made of an ITO film (transparent conductive film) having a thickness of 0.2 μm are juxtaposed in parallel on the substrate 3. Further, over the entire surface of the anode 4, a conductive red light emitting phosphor (hereinafter referred to as R phosphor) 8 for exciting a low-speed electron beam, a conductive green light emitting phosphor (hereinafter referred to as G phosphor) 9, and a conductive material Blue light emitting phosphors (hereinafter referred to as B phosphors) 10 are formed to a thickness of 60 μm. Here, the R phosphor 8 has (Zn, Cd)
S: Ag + In ₂ O ₃ is contained in the G phosphor 9 as ZnO: Zn.
However, ZnS: Zn + In ₂ O ₃ is used for the B phosphor 10. The cathode 2 and the anode 4 are opposed to each other at right angles to each other with the discharge space 5 interposed therebetween, and have a dot matrix structure in which the intersection of the cathode 2 and the anode 4 forms a display dot. The glass substrate 1 and the glass substrate 3 have a height of 0.
It is held at a predetermined interval by a spacer 7 of 2 mm, and the pressure in the discharge space 5 is 500 Torr (p · d product = 10).
He gas of 0 Torr.mm) is enclosed. In this configuration, by applying a voltage equal to or higher than the discharge start voltage between any cathode 2 and the anode 4, gas discharge is generated in the discharge space 5 on the intersection of the cathode 2 and the anode 4 to which the voltage is applied. The discharge current emitted from any cathode 2 flows into the anode 4 through the R phosphor 8, G phosphor 9 or B phosphor 10 formed on any anode 4, and the R phosphor 8 by electron beam excitation, Light emission of the G phosphor 9 or the B phosphor 10 can be obtained.

FIG. 2 shows the light emission efficiency of an electron beam-excited color plasma display panel (invention product) of the present invention and a conventional ultraviolet-excited color plasma display panel (conventional product) in comparison with each other. The curve C shows the case of the product of the present invention, and the curve D shows the case of the conventional product. As the filling gas, He (100%) is used in the product of the present invention, and He-Xe (2%) is used in the conventional product. In the conventional product, the light emission efficiency tends to increase as the p · d product decreases, but since the values of the discharge start voltage and the discharge sustaining voltage are used within practical ranges, as shown in FIG. The product is set near 50 Torr · mm. On the other hand, the luminous efficiency of the product of the present invention is larger than that of the conventional product when the p · d product is in the range of 95 to 140 Torr · mm, and becomes the maximum near 100 Torr · mm. Therefore, the p · d product is 95 to 140 Torr
・ By setting the range to mm, higher luminous efficiency than conventional products can be realized. Moreover, the discharge start voltage and the discharge sustaining voltage at this time are the same as those of the conventional product (p · d product = 50 Torr).
The discharge starting voltage is lower by about 20 V and the discharge sustaining voltage is lower by about 40 V, compared with the case of (mm). Therefore, according to the product of the present invention, while maintaining the same luminous efficiency as that of the conventional product, the driving voltage at the start of discharge is 20% higher than that of the conventional product.
V can be lowered by 40 V in the discharge maintaining state.

Next, a surface discharge type color plasma display panel according to a second embodiment of the present invention will be described with reference to FIG.
Will be explained.

3 (a) and 3 (b), a cathode 2 and an anode 4 are formed on a glass substrate 1 with a space of 0.2 mm, and the surface of the anode 4 is used for low-speed electron beam excitation. The conductive phosphor 9 is formed. Further, the glass substrate 3 facing the glass substrate 1 forms a discharge space 5 with a spacer 7 having a height of 0.1 mm interposed therebetween, and the space 11 is filled with He gas at a pressure of 475 Torr.

In this structure, when a voltage higher than the discharge start voltage is applied between the cathode 2 and the anode 4, the discharge space 5 between the cathode 2 and the anode 4 is generated as shown in FIG. 3 (b). , Arch-shaped discharge current flows. This discharge current is
Since it flows into the anode 4 through the, the phosphor 9 emits light by electron beam excitation. The p · d product in this case is the product of the pressure p of He and the path d from the discharge current to the anode 4 of the discharge current, and the path d from the discharge current to the anode 4 is As shown in FIG. 3 (b), the path is the arc-shaped discharge current path d. Therefore, the product of He pressure p and the path d of the arc-shaped discharge current is 95 to 140 Tor.
By selecting in the range of r · mm, the conventional color
It is possible to obtain higher luminous efficiency than that of the plasma display panel. The second embodiment is different from the first embodiment in that the anode 4 and the phosphor 9 are formed on the same glass substrate 1 as the cathode 2, and thus the glass substrate 3 side facing the glass substrate 1 side. There is nothing that blocks the light emitted from the phosphor 9. Therefore, according to this configuration, the luminous efficiency when the light emission of the phosphor 9 is seen from the glass substrate 3 side can be made higher than that of the opposed discharge type of the first embodiment.

Further, a color plasma display panel which is a third embodiment of the present invention will be described with reference to FIG.

In FIG. 4, a glass substrate 1 has a thickness of 5
A plurality of linear cathodes 2 made of aluminum of μm are juxtaposed in parallel, and on the glass substrate 3 facing them,
Linear anodes 4 made of an ITO film (transparent conductive film) having a thickness of 0.2 μm are juxtaposed in parallel. Furthermore, the anode 4
R for each anode over the entire surface of
Conductive phosphors 8, 9, 10 arranged in G and B for low-speed electron beam excitation are formed with a thickness of 60 μm. The cathode 2 and each anode 4 are orthogonally opposed to each other with the discharge space 5 sandwiched therebetween, and the intersection of the cathode 2 and each anode 4 has a counter discharge type dot matrix structure in which display dots are formed. The discharge space 5 is held by a spacer 7 having a height of 0.2 mm, and the discharge space 5 is filled with He gas having a pressure of 500 Torr (p · d product = 100 Torr · mm). The third embodiment is different from the above-mentioned first and second embodiments in that the discharge space 5 is not divided into small parts by spacers, and R, G, and B are divided into three parts.
It is a point to divide every two. At this time, adjacent display dots that are not divided by the spacer are not turned on at the same time,
An applied pulse as shown in FIG. 5 is input to turn on the lights at different times. For example, when the display dot of G is turned on, each anode 4 on which the G phosphor 9 is arranged,
A potential higher than the discharge start voltage is applied to the cathode 2, and R, B
If the same potential as that of the cathode 2 is applied to each of the anodes 4 in which the above-mentioned phosphors are arranged, the discharge current flows only into the G phosphor 9 and does not flow into the R / B phosphors 8 and 10. Only luminescence is obtained. In the case of R and B, this operation is similarly performed at different times, so that each of R, G and B can be made to emit light in the discharge space 5. Since only the phosphor in the part where the discharge current flows in emits light, R,
Even if the inside of the discharge space containing G and B is not finely divided by the spacer, the light emitting region of the phosphor can be limited, and the non-selected display dots will not be erroneously emitted. According to this configuration, the number of spacers can be reduced to 1/3 of that of the conventional one, so that a plurality of display dots share one discharge space 5, which facilitates miniaturization of the display dots.

[0016]

As described above, according to the present invention, the discharge start voltage and the discharge sustaining voltage can be lowered as compared with the conventional case while maintaining the luminous efficiency with the conventional color plasma display panel. As a result, it is possible to use, as the semiconductor element of the driving circuit, for example, an IC having a low breakdown voltage and an inexpensive one, and it is possible to reduce the cost.
Further, since electrons having a high electron temperature can be made to flow into the phosphor, the luminous efficiency of the phosphor by electron beam excitation can be made equal to or higher than that in the case of ultraviolet excitation. Furthermore, since electrons can be made to flow only into the target anode, the number of spacers used to prevent crosstalk can be reduced compared to the past, resulting in a smaller dot pitch and higher display density. This facilitates realization of a high-definition color plasma display panel.

[Brief description of drawings]

FIG. 1A is a plan view showing the basic structure of a color plasma display panel according to a first embodiment of the present invention, and FIG. 1B is a side sectional view of the same.

FIG. 2 is a diagram showing the relationship between the luminous efficiency of the conventional color plasma display panel and the color plasma display panel of the present invention, and the product of the gas pressure and the distance from the cathode to the anode.

FIG. 3A is a plan view showing the basic structure of a color plasma display panel which is a second embodiment of the present invention, and FIG.

FIG. 4A is a plan view showing the basic structure of a color plasma display panel which is a third embodiment of the present invention. FIG. 4B is a side sectional view of the same.

FIG. 5A is a diagram showing a lighting timing of R, G, and B during green light emission; and FIG. 5B is a diagram showing a lighting timing of R, G, and B during white light emission.

FIG. 6A is a plan view showing the basic structure of a conventional color plasma display panel, and FIG. 6B is a side sectional view of the same.

FIG. 7 (a) He (100%) and He-Xe (2%).
Showing the relationship between the discharge start voltage of the battery and the product of the gas pressure and the distance from the cathode to the anode. (B) From the gas pressure and the cathode of the discharge sustaining voltage of He (100%) and He-Xe (2%). Diagram showing the relation to the product with the distance to the anode

[Explanation of symbols]

 1,3 Glass substrate 2 Cathode 4 Anode 5 Discharge space 8, 9, 10 Conductive phosphor for low-speed electron beam excitation

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01J 17/04 9376-5E

Claims (3)

[Claims] 1. A phosphor provided in a discharge space by enclosing a gas between substrates each having a cathode and an anode provided on the inner surface, and applying a voltage between the cathode and the anode to cause gas discharge. In the plasma display panel that excites
The gas consists of helium, and the phosphor is a conductive phosphor for low-speed electron beam excitation, the conductive phosphor is formed on the anode, the distance between the cathode and the anode, The product of the filling pressure of helium is 95 to 14
The color is characterized in that the discharge current emitted from the cathode flows into the anode through the conductive phosphor to obtain light emission of the conductive phosphor by electron beam excitation by selecting the range of 0 Torr · mm.・ Plasma display panel. 2. A gas is enclosed between a substrate having a cathode and an anode provided on the inner surface thereof, and a voltage is applied between the cathode and the anode to generate gas discharge, which is provided in a discharge space. In a plasma display panel that excites a phosphor, the gas is made of helium, and the phosphor is made of a conductive phosphor for low-speed electron beam excitation, and the conductive phosphor is formed on the anode. , The product of the discharge current from the cathode to the anode and the filling pressure of helium is selected in the range of 95 to 140 Torr · mm, and the discharge current emitted from the cathode is the conductive phosphor. A color plasma display panel, characterized in that light emission of the conductive phosphor by electron beam excitation is obtained by flowing into the anode through. 3. A conductive phosphor for exciting a low-speed electron beam, which is different from red, green, or blue, on each of adjacent anodes which are not separated by a spacer among a plurality of anodes paired with a cathode. A discharge current emitted from the cathode is caused to flow into any of the red, green, and blue conductive phosphors by forming a potential difference between the adjacent anodes. 1. The color plasma display panel according to 1.