JP2889058B2 - Driving method of gas discharge display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a gas discharge display device, and more particularly, to a memory type driving method.

[0002]

2. Description of the Related Art A gas discharge display device has attracted attention as one of means for realizing a large flat panel display. One example is disclosed in Document I (Television Society Journal Vol.40, No10 (1986) p953-960). FIGS. 7A and 7B are diagrams provided for the description, and are both perspective views schematically showing respective parts of the gas discharge display device disclosed in Document I.

In this gas discharge display device, as shown in FIG. 7 (B), a predetermined number of cathodes 12 are arranged in parallel on a rear substrate 10, and further, auxiliary cells 14 and display cells 16 are provided.
Are provided.

As shown in FIG. 7A, a display anode 22 and an auxiliary anode 24 are arranged in parallel at predetermined positions on a light-transmitting front substrate 20 (eg, a glass substrate). The coating is applied so that the display anode 22 is exposed and opposed to the display cell 16.

The back substrate 10 and the front substrate 20
However, in a state where the cathode 12 and the anodes 22 and 24 are arranged so as to cross each other so that the respective electrode forming surfaces face each other,
The two substrates are sealed at hermetic sealing portions (not shown) on the outer peripheral portions. A gas medium for discharge is sealed in a gap between the two substrates.

[0006] In this type of gas discharge display device, when the display device is driven line-sequentially, the time allocated to each scanning line (usually each cathode) is short, so that the larger the display device is, the more practical it becomes. It is difficult to obtain a high luminance. In order to solve this, in the above-mentioned Document I, a driving method based on a pulse memory system as described below is used. In the following description, in order to simplify the description of this driving method, the gas discharge display device shown in FIG.
, Four display anodes 221 to 224 and 4
It is assumed to have a four-row, four-column configuration including the cathodes 121 to 124 (indicated by 28 in FIG. 8). In FIG. 8,
16 _MN (16 ₂₂ , 16 _24, etc.) represents a display cell in the M-th row and the N-th column. 30 is a write pulse generation circuit, 3
2 is a sustaining pulse generating circuit, 34 is a scanning pulse and erasing pulse generating circuit, 36 is an auxiliary discharge current controlling resistor,
Reference numeral 8 denotes a power supply, and diodes D ₁ and D ₂ constitute an adder for mixing a write pulse and a sustaining pulse. FIG. 9 is a waveform diagram showing signals applied to the main part of the gas discharge display device in the conventional driving method.

In the driving method disclosed in Document I, as shown in FIG. 9, the pre-bias voltage is V ₁ (for example, −80).
Scanning pulse P _K of scanning voltage V ₂ (e.g., -220V) by V) is, first line, second line, third line, the line is sequentially applied to the fourth row of the cathode 121 to 124 You. On the other hand, the anode 221 to 224 sustain voltage in the pre-bias voltage V ₃ to each (for example, 0V) is sustaining pulse P _S of V ₄ (e.g. 140 V) is applied in period T. However, it applied so as not to overlap the timing the scanning pulse P _K and sustaining pulse P _S. This is to prevent the occurrence of erroneous discharge due to the sustaining pulse P _S. Further, since the auxiliary anode 241 and 242 are applied constant positive voltage is constantly the power supply 38, the auxiliary cell 14 to cathode scanning pulse P _K is applied slide into sequentially discharged. For example, time t
₁ in a period ~t ₂ scan pulse P _K cathode of the second row 1
Thus, a discharge current flows in the auxiliary cell in the second row. Charged particles, metastable particles, and the like generated in the auxiliary cell due to the discharge of the auxiliary cell are displayed on the display cell 1 near the auxiliary cell.
Diffusion to 6. Also, (when writing of the display cell 16 _MN) when generating a normal discharge in the display cells 16 _MN, the cathode 12 of the cathode (second line in the illustrated example of the M-th row
2) When the scanning pulse is applied substantially in synchronization with
The pre-bias voltage is V ₃ (0 V in this case) and the write voltage is V
₅ write pulse P _W (for example 100 V) is applied, between a cathode and an anode voltage of (V ₅ -V ₂₎ is applied. At this time, since the charged particles, metastable particles, and the like are diffused from the auxiliary discharge cells into the display cell 16 _MN as described above, the regular discharge quickly occurs in the display cell 16 _MN . This is a so-called priming effect. Ultraviolet light generated by the discharge excites the phosphor 26 (see FIG. 7A), so that light corresponding to the phosphor is obtained in the display cell. Here, when a normal discharge occurs, a current flows in the display cell 16 _MN , but the current decreases as the write pulse _PW stops. But,
When such charged particles generated by discharge remain in the display cell properties such easily re discharges in the display cell shown in gas discharge, further discharge sustaining pulse P _s at a moderate period T in this driving method is the anode Since the voltage is applied, the potential difference (V ₄ −V ₁ ) between the sustain voltage V ₄ of the discharge sustain pulse and the pre-bias voltage V _{1 of the} scan pulse causes
As shown in the 16 _22, discharge current normal discharge is a memory occurs intermittently (pulse memory method). As a result, even when the number of scanning lines increases (for example, when the number of scanning lines becomes about 1000), desired luminance can be obtained. When the discharge is stopped, the erasing voltage V ₆ (for example, −10) is applied to the cathode.
The potential difference between the anode and the cathode is reduced by applying an erase pulse P _E of V).

[0008]

However, in the conventional driving method described above, the bias voltage V ₁ ,
Three voltage of the scanning voltage V ₂ and the erase voltage V ₆ to selectively supply, it is necessary to selectively supply three voltage of the bias voltage V _3, the sustain voltage V ₄ and the write voltage V ₅ to the anode . Therefore, each of the driving circuit on the cathode side and the driving circuit on the anode side needs to be able to output three voltage values, and there is a problem that the cost of the driving circuit is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a driving method capable of reducing the cost of a driving circuit when a gas discharge display device is driven by a pulse memory system. To provide.

[0010]

According to the present invention, a cathode and an anode are arranged to face each other with a discharge gas interposed therebetween, and a gas for controlling the discharge of the discharge gas by the cathode and the anode is provided. In the driving method of the discharge display device, a cathode-side sustaining pulse that changes from a first potential to a second potential for a predetermined time is applied to the cathode at a cycle sufficient to maintain the discharge, and the third potential is applied to the anode. To the fourth potential and apply the anode-side sustaining pulse having the same phase as the cathode-side sustaining pulse, and the discharge is generated immediately before or immediately after the cathode sustaining pulse with respect to the cathode. The cathode-side write pulse that takes the second potential is further applied without any time interval to extend the time during which the cathode becomes the second potential, and the cathode-side write pulse is applied to the anode. Same as Further applying an anode side write pulse taking fourth potential life-and-death foregoing, the aforementioned anode fourth
The discharge is stopped by extending at least one of the above-mentioned cathode side sustaining pulse and anode side sustaining pulse for at least one pulse. .

In the present invention, the write pulse is further applied immediately before or immediately after the sustaining pulse without any time interval. The term “not separated” means that when one pulse is about to fall, the other pulse rises In either case, either of the two pulses may be overlapped. In addition,
In the description, the first potential and the third potential may be the same.
No. Because, even in such a case, the cathode side drive circuit
Outputs two values of the first potential and the second potential, and drives the anode side
The circuit has a third potential and a fourth potential (actually, a first potential).
And the fourth potential), it is sufficient to output
This is because the driving circuit can be simplified as compared with the case of FIG.

In the practice of the present invention, a discharge is generated by the above-described cathode instead of the above-described discharge generation method (hereinafter, referred to as a “discharge generation method by extending a pulse width” for convenience of explanation). On the other hand, this is performed by applying a cathode-side write pulse having a fifth potential and applying an anode-side write pulse having the fourth potential in synchronization with the cathode-side write pulse to the anode. You can also. Hereinafter, this discharge generation method is referred to as a “discharge generation method based on an increase in potential difference” for convenience of explanation.

In practicing the present invention, in the case where the gas discharge display device has a structure in which a plurality of cathodes and a plurality of anodes are arranged to face each other in a grid pattern, the above-mentioned cathode-side write pulse is preferably used as a scanning pulse. .

[0014]

In the present invention, in the configuration using the discharge generation method by extending the pulse width, the cathode-side drive circuit only needs to be capable of outputting two values of the first potential and the second potential. May output a binary value of a third potential and a fourth potential. In the configuration using the discharge generation method by increasing the potential difference, the cathode side drive circuit needs to be capable of outputting first, second and fifth ternary values, whereas the anode side drive circuit is of a binary output type. Is good.

[0015]

An embodiment will be described below with reference to an example in which the driving method of the present invention is applied to the driving of the gas discharge display device 28 described with reference to FIG. This description is made with reference to some drawings. However, the drawings used in the description merely schematically show the dimensions, shapes, and arrangements of the components so that the present invention can be understood.

1. First embodiment (example using discharge generation method by extending pulse width) 1-1. Description of Relationship between Pulse Width and Discharge Generation and Discharge Sustain Prior to the description of the first embodiment, when a pulse-like voltage is applied between the anode and the cathode, how the discharge voltage and discharge sustain voltage of the display cell are affected by the pulse width It will be described what is done.

The margin for the write pulse on the anode side and the margin for the sustaining pulse on the anode side in the gas discharge display device disclosed in Document I, which are the driving targets in this embodiment, are those shown in FIG. This is shown in FIG. The characteristic diagrams shown in FIGS. 3 and 4 indicate the following. First, in FIG.
The plot indicated by V _WMIN shows the anode-side write voltage at which all selected display cells in the gas discharge display device normally start discharging when the anode-side write pulse width is used as a parameter. _Further , the plot indicated by V _WMAX indicates that the discharge also starts to the non-selected display cells in the gas discharge display device (that is, the erroneous discharge starts) when the anode-side write pulse width is also used as a parameter. It shows a write voltage. However, as described above, these margins are obtained when the scanning voltage of the scanning pulse on the cathode side is -220 V and the pre-bias voltage is -80 V (the same applies to the following description of the characteristics in FIG. 4). In FIG. 4, a plot indicated by V _SMIN indicates that a discharge of a selected display cell in a gas discharge display device can be started when the anode-side discharge sustain pulse width is used as a parameter (a normal discharge may occur depending on the viewpoint). Can be maintained)
The plot showing the anode-side discharge sustaining voltage and the plot indicated by _VSMAX also indicate that discharge started to a non-selected display cell in the gas discharge display when the anode-side discharge sustaining pulse width was also used as a parameter. (I.e., erroneous discharge starts) on the anode side. Therefore,
From FIG. 3, in order to discharge the display cell of the gas discharge display device in this case, at least V _WMIN +2 between the cathode and the anode.
It can be seen that a voltage of 20 V needs to be applied. Further, from FIG. 4, in order to maintain the discharge of the display cell of the gas discharge display device in this case, at least V is applied between the cathode and the anode.
It can be seen that it is necessary to apply a voltage of _SMIN + 80V.

Therefore, V _WMIN in the characteristic diagram of FIG.
V, and V _SMIN in the characteristic diagram of FIG.
The characteristic diagram shown in FIG. 5 is obtained by _summing the values obtained by adding 80 V to each of the VSMAXs in a common diagram. The characteristic diagram of FIG. 5 shows a margin α of the sustaining voltage applied between the cathode and the anode and a margin β of the firing voltage in the gas discharge display device. Here, the inventor of the present application has noticed that the pulse width is different even at the same voltage.
This means that the voltage becomes both the writing voltage and the sustaining voltage. Specifically, when the voltage between the anode and the cathode is, for example, 290 V, as is clear from FIG. 5, if this voltage is applied with a pulse width of 0.5 μs, this voltage becomes the discharge sustaining voltage, and the pulse width becomes 1 This voltage becomes a write voltage if applied in 0.0 μs. The first embodiment makes use of this property. This will be specifically described below.

1-2. Specific Example of First Embodiment FIG. 1 is a time chart for explaining a first embodiment of the driving method according to the present invention. FIG. 2 is a diagram showing a wiring structure between the gas discharge display device 28 and the drive circuit. Since the configuration of the display device 28 has already been described, it is omitted.

Each of the cathodes 121 to 124 of the display device is connected to a scanning signal generation circuit 300 as a cathode side driving circuit, and each of the anodes 221 to 224 is connected to a data signal generation circuit 310 as an anode side driving circuit. It is. Each of the auxiliary anodes 241 and 242 has a resistor 3 as in the conventional case.
The power supply 38 is connected through the power supply 6.

The scanning signal generation circuit 300 is provided for each of the cathodes 121.
１２４124 for a predetermined time τ from a pre-bias voltage V _PK (for example, 140 V) as a first potential to a cathode-side sustaining voltage V _SK (for example, 0 V) as a second potential.
_The cathode-side discharge sustaining pulse P _SK that changes by _SK (for example, 0.5 μs) can be applied at a period T (for example, 4 μs) at which discharge can be maintained.
24, line-sequentially and (the number of cathodes M × the above period T) = MT
In this cycle, a scanning pulse P _K (this is a cathode-side write pulse) that changes from the V _PK to the V _SK for a predetermined time (in this case, 0.5 μs) can be applied. However, the scanning pulse P _K is applied immediately before or immediately after the cathode-side discharge sustaining pulse P _SK (immediately after in the example of FIG. 1) at no interval. Therefore, the relevant cathode when the scan pulse P _K arrives, takes voltage 1μs of the scan pulse P _K and V _SK by cathodic side sustaining pulse P _SK, the cathode side discharge maintained at other times to the cathode The pulse P _SK causes the voltage of V _SK to be 0.5 μs in the cycle of T (see the waveform diagrams of the cathodes 121 to 123 in FIG. 1).

On the other hand, the data signal generating circuit 310 applies a voltage from the pre-bias voltage V _PA (for example, 150 V) as the third potential to the anode-side discharge sustaining voltage V _SA as the fourth potential for each of the anodes 221 to 224. (For example, 290 V), the same time τ _SA (0.5 μ
The anode side discharge sustain pulse P _SA where s) change, with those that can be respectively applied at the cathode side sustaining pulse in phase, into the appropriate one or more anodes according to the display data V
_The anode-side write pulse P _W taking the potential of _SA can be applied in synchronization with the cathode-side write pulse (scan pulse P _K ). Therefore, the anode-side write pulse P
The _W anode applied voltage of V _SA by anodic side writing pulse P _W and the anode-side sustaining pulse P _SA is 1μ
s takes (time t ₁ ~t ₂ reference waveforms of the anode 222 in FIG. 1.), voltage V _SA at a period of T is the other anode side sustaining pulse P _SA is in the anode time of 0.5μs
That would be.

As a result, in the example of FIG. 1, the cathode 122 in the second row and the anode 222 in the second column of the gas discharge display device 28 are used.
Voltage V _SA -V _SK is to be 1μs applied between cathode and anode of the display cell 16 ₂₂ (see FIG. 2) between.

Here, in the gas discharge display device 28 to be driven in this embodiment, when the same voltage is applied between the cathode and the anode as already described with reference to FIG. Described that both the discharge starting voltage and the discharge sustaining voltage were obtained. Then, the voltage application time to the display cell 16 ₂₂ of the above-mentioned 1μs satisfies the firing condition in FIG. Thus the display cells 16 ₂₂ In normal discharge occurs (see time t ₁ ~t ₂ waveform diagram of the display cell current 16 ₂₂ in FIG. 1). Then, the display cell 16 ₂₂
Discharge that occurred in is maintained by the cathode-side sustaining pulse P _SK and the anode-side sustaining pulse P _SA (see time t ₃ ~t ₆ waveform diagram of the display cell current 16 ₂₂ in FIG. 1). The principle of maintaining the discharge is the same as the conventional one. However, the present invention is different in that the voltage of the sustain pulse is shared between the anode side and the cathode side. In order to stop the generated discharge, at least one of the cathode-side sustaining pulse and the anode-side sustaining pulse may be stopped for at least one pulse. Discharge showing a state that is erased at the time t ₇ ~t ₈ of the waveform diagram of the display cell current 16 ₂₂ of FIG.

In the driving method of the first embodiment, the anode side,
Any of the driving circuits on the cathode side can drive the display device only by outputting two values of the pre-bias potential and the sustaining potential.

It should be noted that each of the above-described scanning signal generation circuit 300 and data signal generation circuit 310 can be constituted by a conventionally known electric circuit technique.

2. Second Embodiment (Example of Using Discharge Generation Method by Increasing Potential Difference) In the above-described first embodiment, an example in which each of the driving voltages on the cathode side and the anode side can be binary, thereby reducing the cost of the driving circuit. Met. However, even when one of the driving voltages on the anode side and the cathode side is binary, the cost of one of the anode side driving circuit and the cathode side driving circuit can be reduced, and the cost of the entire driving circuit can be reduced. This second embodiment is an example.

[0028] Therefore, in this second embodiment, the anode side by applying a write pulse P _W in the sustaining pulse P _SA and timely in the same manner as the first embodiment, the cathode side as in the first embodiment _Is applied with a sustaining pulse _PSK . However, only for the cathode side write pulse (scan pulse in this case)
The potential is set to a potential V lower than the potential V _SK in the first embodiment.
_K , and the pulse width is set to a pulse width τ _K2 shorter than that of the first embodiment. FIG. 6 is a signal waveform diagram for explanation thereof, and corresponds to FIG. Here, the potential V _K and the pulse width τ _K2 of the scan pulse in the second embodiment may be values that can generate a normal discharge by the scan pulse and the anode-side write pulse P _W. For example, as shown in FIG. Can be determined from the β region in the characteristic diagram. For example, consider the case where a discharge is started by applying a voltage of 320 V between the anode and the cathode with a pulse width of about 0.8 μs. Since the anode-side discharge sustaining voltage V _SA = 290 V, the scanning voltage V _{K in} this case is 290 -320 = -30V.

In the driving method of the second embodiment, the cathode side needs to output three potentials of -30 V, 0 V, and 140 V, but the anode side may be binary. For this reason, the cost of the drive circuit can be reduced as compared with the related art in the second embodiment.

Although the embodiment of the method for driving the gas discharge display device of the present invention has been described above, the present invention is not limited to the above embodiment. For example, the potentials illustrated are merely examples, and can be changed according to the design of the display device. Further, the gas discharge display device that can be driven by the driving method of the present invention is not limited to the one shown in FIG.

[0031]

As is apparent from the above description, according to the method of driving a gas discharge display device of the present invention, the types of voltage values required for driving can be reduced. Therefore, the driving circuit can be simplified, and the cost of the driving circuit can be reduced.

[Brief description of the drawings]

FIG. 1 is a time chart for explaining a driving method according to a first embodiment.

FIG. 2 is a diagram for explaining a driving method according to first and second embodiments, and is a diagram illustrating a connection relationship between a gas discharge display device and a driving circuit.

FIG. 3 is a diagram provided for explaining the first embodiment, and is an explanatory diagram of a margin of a write voltage on an anode side in a display device to be driven.

FIG. 4 is a diagram provided for explanation of the first embodiment, and is an explanatory diagram of a margin of an anode-side discharge sustaining voltage in a display device to be driven.

FIG. 5 is a diagram provided for explanation of first and second embodiments,
Discharge start voltage in the display cell of the display device to be driven,
FIG. 4 is an explanatory diagram of each margin of a discharge sustaining voltage.

FIG. 6 is a time chart for explaining a driving method according to a second embodiment;

FIG. 7 is a diagram showing an example of a gas discharge display device.

FIG. 8 is a diagram showing a wiring structure for a conventional driving method.

FIG. 9 is a time chart for explaining a conventional driving method.

[Explanation of symbols]

10: rear substrate 12: cathode 14: auxiliary cell 16: display cell 20: front substrate 22: anode 24: auxiliary anode 26: phosphor 36: resistor 38: power supply 121-124: cathode 221-224:
Anodes 241 and 242: auxiliary anode 300: cathode side drive circuit 310: anode side drive circuit

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mio Chiba 1-7-12 Toranomon, Minato-ku, Tokyo Inside Oki Electric Industry Co., Ltd. (72) Inventor Hiroshi Toyama 1-7-12 Toranomon, Minato-ku, Tokyo No. Oki Electric Industry Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) G09G 3/00-3/38

Claims (4)

(57) [Claims] 1. A driving method for a gas discharge display device in which a cathode and an anode are arranged to face each other with a discharge gas interposed therebetween, and the cathode and the anode control the discharge of the discharge gas. A sustaining pulse which changes to the potential for a predetermined time is applied at a cycle sufficient to maintain the discharge, and the anode is changed from the third potential to the fourth potential and in phase with the cathode-side sustaining pulse. Applying an anode-side sustaining pulse of the above, and generating a discharge, further applying a cathode-side write pulse that takes the second potential to the cathode immediately before or immediately after the cathode sustaining pulse without taking a time interval. Along with extending the time at which the cathode is at the second potential, further applying an anode-side write pulse that takes the fourth potential in synchronization with the cathode-side write pulse to the anode, The discharge is performed by extending the time during which the anode has the fourth potential, and the discharge is stopped by stopping at least one of the cathode-side sustaining pulse and the anode-side sustaining pulse for at least one pulse. driving how the gas discharge display device characterized. 2. A method for driving a gas discharge display device in which a cathode and an anode are arranged to face each other with a discharge gas interposed therebetween, and the discharge of the discharge gas is controlled by the cathode and the anode. A discharge sustaining pulse which changes to the potential for a predetermined time is applied at a period sufficient to maintain the discharge, and the anode is changed to the fourth potential from the same third potential as the first potential to the fourth potential, Applying an anode-side sustaining pulse having the same phase as the side-sustaining sustaining pulse, and generating a discharge with respect to the cathode, the cathode having the second potential immediately before or immediately after the cathode sustaining pulse with no time interval. An anode-side write pulse that further applies a side write pulse to extend the time during which the cathode is at the second potential, and that is synchronized with the cathode-side write pulse and has the fourth potential with respect to the anode. The discharge is stopped by extending the time during which the anode is at the fourth potential, and the discharge is stopped by at least one of the cathode-side sustaining pulse and the anode-side sustaining pulse for at least one pulse. driving how the gas discharge display device characterized by performing by stopping. 3. A method for driving a gas discharge display device according to claim 1 or 2, generation of the discharge, instead of the method generating the discharge, relative to the cathode, a smaller value than the second potential The method is characterized by applying a cathode-side write pulse having a certain fifth potential and applying an anode-side write pulse having the fourth potential in synchronization with the cathode-side write pulse to the anode. driving how the gas discharge display device according to. 4. A method for driving a gas discharge display device according to claim 1, wherein the gas discharge display device has a structure in which a plurality of cathodes and a plurality of anodes are arranged to face each other in a grid pattern. A driving method of the gas discharge display device, wherein the cathode-side write pulse is a scan pulse.