JPH0797266B2 - Driving method for gas discharge display panel - Google Patents

Description

TECHNICAL FIELD The present invention relates to a driving method of a pulse memory driving method for a gas discharge display panel.

(Prior Art) For example, a pulse memory driving method described in Japanese Patent Application Laid-Open No. 57-86886 “Driving method of gas discharge display panel”, which is the applicant of the present invention, has a memory function in a discharge display panel having a relatively simple structure. This is an advantageous method for obtaining a flat display device with high brightness.

FIG. 4 shows a schematic panel electrode connection diagram of the discharge display panel used in the above-mentioned driving method, and FIG. 5 shows a conventional example of a pulse drive waveform for each main electrode application pulse and a discharge current waveform. The pulse memory driving method and operation principle will be briefly described.

The sustain pulse SP is constantly applied to the display anode DA _j (j = 1, 2 ... N) at a constant cycle T, and the pulse width τ _SP of this sustain pulse and the peak voltage V _SP are written once by the write pulse WP. It is preset so that the discharge can be maintained continuously. That is, when there is no write pulse WP, no discharge is generated by the sustain pulse SP, but once discharge is generated by the write pulse WP, pulse discharge is repeated and continues. Meanwhile cathode K _i (i is maintained at a normal voltage level V _CA
= 1,2 ... m), the first row cathode K ₁ to the mth row cathode k _m
The scan pulse SKP having the negative voltage V _K from the level V _CA is sequentially applied toward the scanning direction. As a result, the auxiliary cells S _ij are sequentially discharged from the first row with the help of the auxiliary anodes SA _j (J = 1, 2 ... N). Here, for example, when writing to the display cell D ₂₂ , the write pulse WP of the voltage V _W is applied to the corresponding display anode DA _2.
Is applied at substantially the same timing as the discharge of the auxiliary cell S ₂₂ . The address discharge is sufficiently quick due to the ionization coupling between the display cell D ₂₂ and the auxiliary cell S ₂₂ (priming effect). To stop the discharge of the display cell D ₂₂ , the erase pulse EP of the erase voltage V _ER may be applied to the corresponding cathode K ₂ and the discharge of the sustain pulse SP may be stopped once or more.

(Problems to be Solved by the Invention) In the conventional driving method, the sustain pulse SP is applied immediately after the scan discharge (auxiliary discharge) and the address discharge. For this reason, the ionization coupling between the display cell D _ij and the auxiliary cell S _ij becomes large, and if the priming is excessive, erroneous discharge occurs due to the sustain pulse SP immediately after the scan discharge without writing, and for memory use. However, there is a problem that the pulse height margin (possible limit) of the sustain pulse is reduced.

Since the variation in the degree of ionization coupling between the display cell D _ij and the auxiliary cell S _ij depends on the component accuracy, it tends to increase as the panel becomes larger. Therefore, as the panel becomes larger, the number of discharge cells with excessive priming increases and the above-mentioned sustain pulse margin is significantly reduced.

Further, in the flat panel, the auxiliary cell is a non-light emitting portion and visually impedes, so that it is preferable that the auxiliary cell is thin. However, if the discharge is made thin, the scanning (auxiliary) discharge becomes unstable, and if the discharge is strengthened to stabilize the discharge, the priming becomes excessive and the above-mentioned problem occurs.

Therefore, an object of the driving method of the present invention is to provide a driving method of a gas discharge display panel with improved memory margin and stable auxiliary discharge and display discharge by improving the configuration of the driving method of the prior art. To do.

(Means for Solving the Problems) In order to achieve this object, the method for driving a gas discharge display panel according to the present invention is to drive a pulse memory type discharge display panel immediately after a scanning pulse applied to a cathode. The cathode potential is set to the erase voltage level for a predetermined period, and when there is no write pulse applied to the display anode for writing in the period corresponding to the scan pulse, an erroneous discharge does not occur due to the sustain pulse applied thereafter. None, which allows the margin of the sustain pulse applied to the anode (possible limit)
Is increased.

The present invention has been proposed on the basis of the fact that the influence of the charged particles or the like generated by the auxiliary discharge on the start of the sustain discharge is smaller than the influence of the charged particles or the like generated by the address discharge on the start of the sustain discharge.

(Example) With reference to the accompanying drawings, the present invention will be described in detail below with reference to an example.

FIG. 1 shows a first embodiment of the electrode driving waveform according to the driving method of the present invention. That is, the cathode K _i is kept at the erasing voltage level V _ER for a predetermined period T _W immediately after the scan pulse SKP, and the same pulse waveform as in the past is applied to the other display anode DA _j and the auxiliary anode SA _j. To be done. Here, the length of the period T _W is from one cycle of the minimum sustain pulse to about 20 cycles at the maximum.

In this way, when there is no write pulse WP, charged particles and quasi-particles diffused from the auxiliary cell S _ij to the display cell D _ij by the scanning discharge (auxiliary discharge) by the scanning cathode (cathode) pulse SKP by the cathode K _i. Stable particles and the like are erased during the period T _W , and erroneous discharge due to the sustain pulse SP based on this is prevented. On the other hand, when there is the write pulse WP, the write discharge is performed inside the display cell itself, so that the number of charged particles and the like generated by this is an order of magnitude larger than that of particles due to the priming of the auxiliary discharge, and even after the period T _W. A sufficient amount can be left to initiate a sustain discharge.

The experimental results demonstrating the above results are shown in FIG. This is a calculation of the margin of the sustain pulse voltage when writing is performed in a checkered pattern on about 50 × 50 cells by using the planar configuration discharge display panel by the present applicant (TV
See Technical Report of the Society, IPD98-3, pp13-18, 1985). The horizontal axis represents the period T _W , and the vertical axis represents the sustain pulse voltage V _SP . In FIG. 3, the actual measurement value V _{SP min.} Is the voltage at which all the cells to which the write pulse WP is applied sustain pulse discharge, and the actual measurement value V _{SP.
SP max.} Is a voltage at which at least one cell to which the write pulse WP is not applied causes erroneous discharge. As can be seen from FIG. 3, in the discharge panel used in the experiment, the sustain pulse voltage margin could not be secured in the conventional example due to the variation in the priming interval between each display cell and the auxiliary cell, that is, the variation in the degree of ionization coupling. According to the method of the present invention, a margin of about 20 V could be secured as shown in FIG. It is clear from the experimental results that the length of the period T _W that can be taken here can be a period from one cycle of the minimum sustain pulse to the time when writing can be reliably performed, that is, a dozen cycles of the sustain pulse interval.

In FIG. 1, the potential of the cathode immediately before the scan pulse SKP of the cathode K _i does not have to be the potential V _CA necessary for continuing the sustain pulse discharge by the sustain pulse. This is because the sustain pulse discharge is normally erased at this timing. In the extreme case, the waveform shown in FIG. 2 also produces the same effect as in the case shown in FIG. 1, and this is the second embodiment of the present invention.

In the first and second embodiments, the cathode is set to the constant potential V _CA during the sustain pulse duration, but this is not the only option.
The potential V _CA may be applied in pulses to the cathode in accordance with the phase of the sustain pulse applied to the display anode.

The driving circuit for generating the pulse waveform described above can be easily configured by combining circuit components such as a transistor, a field effect transistor, and an integrated circuit. It should be noted that the slight deviation of the timing in FIGS. 1 and 2 does not affect the essence of the present invention.

Further, the driving method of the present invention can be applied to all types of gas discharge display panels which perform pulse memory driving including scanning (auxiliary) discharge, and a semi-AC type driving panel which is the applicant of the present invention, for example, JP-A-60-121648. It can also be applied to the "gas discharge display panel". Further, it is needless to say that the present invention can be applied to the graphite cathode memory panel with auxiliary discharge described in the specification of Japanese Patent Application Laid-Open No. 53-65657, "Gas Discharge Display Panel".

The driving method of the present invention can be most effectively applied to the line-sequential scanning method shown in FIG. 5, and stable discharge is easily obtained because the auxiliary discharge also moves sequentially. Kaji et al .: TV Society Image Display System Study Group Material No. 11-4, 1973). In this case, since the auxiliary discharge can be strongly performed, stable auxiliary discharge can be obtained even without sequential scanning. Data can be written.

The driving method of the present invention is that the sustain pulse discharge is started after a certain period of time after the scanning discharge, and thus the present invention is applied to the present invention.
-194495 "Driving method of gas discharge display panel" is similar to the driving method described in the specification, but the method of the present invention performs auxiliary discharge and address discharge at the same time.
It is different from the content of 60-194495.

Also, a driving method similar to the method of the present invention can be applied to a Townsend panel such as "High Efficacy Townsend Discharge Memory Pa
nel for Color TV Display ", Proc. of Japan Display
'83, pp510-513. However, this panel is completely different in structure and operation mode from the panel to which the method of the present invention is applied.In this driving method, each cell is accompanied by a large resistance. Therefore, a stable auxiliary discharge can be obtained by always applying a large voltage. Therefore, while paying attention only to writing, the method of the present invention provides a stable auxiliary discharge even for an auxiliary cell as narrow as possible. The aim is to wake up the cell and at the same time to write the display cell stably. Further, the Townsend discharge memory panel of this document is clearly different from the control of the voltage applied to the cathode of the method of the present invention in that the sustain pulse is applied only to the display anode.

(Effect of the Invention) First, the driving method of the present invention brings about an increase in the margin of the memory pulse in the pulse memory driving method of the discharge display panel. Especially when the priming such as auxiliary discharge is excessive, the effect is great. For this reason, the scanning (auxiliary) discharge can be strongly performed, the stabilization thereof can be achieved, and at the same time, the memory margin can be increased. Therefore, particularly in a flat panel panel, this allows the width of the auxiliary cell to be narrowed and the visual interference thereof to be reduced.

In addition, since it is possible to eliminate the influence of variations in the priming amount due to variations in the priming gap between the display cells and the auxiliary cells of the panel, holes, etc., it is possible to ease the panel manufacturing accuracy and facilitate the production. You can This works effectively when the panel is made large and the definition is high, and is effective for realizing a flat display for high-definition television.

[Brief description of drawings]

1 and 2 are diagrams showing first and second examples of associated electrode driving waveforms according to the method of the present invention, respectively, and FIG. 3 is a diagram showing experimental results of sustain pulse voltage margin according to the present invention. FIG. 4 is a schematic panel electrode connection diagram of a discharge display panel to which the present invention is applied, and FIG. 5 is a diagram showing a conventional example of a drive waveform and a discharge current waveform applied to each main electrode of the display panel shown in FIG. . K _i (i = 1,2 ... m) ... cathode SA _j (j = 1,2 ... n) ... auxiliary anode DA _j (j = 1,2 ... n) ... display anode S _ij ... auxiliary cell , D _ij …… Display cell SP …… Maintain pulse, WP …… Write pulse EP …… Erase pulse, SKP …… Scan (cathode) pulse

Front page continuation (72) Inventor Hitoshi Nakagawa 1-10-11 Kinuta, Setagaya-ku, Tokyo Inside the Japan Broadcasting Corporation Broadcasting Technology Laboratory (72) Inventor Masahiko Seki 1-10-11 Kinuta, Setagaya-ku, Tokyo (72) Inventor Yuho Kitada 1-10-11 Kinuta, Setagaya-ku, Tokyo Inside Broadcasting Technology Institute, Japan Broadcasting Corporation

Claims (1)

[Claims] 1. When driving a pulse memory type discharge display panel in which a sustain pulse is continuously applied between a display anode and a cathode, a cathode potential immediately after a scan pulse is set to an erase voltage level for a predetermined period, and an error due to a sustain pulse is generated. A method for driving a gas discharge display panel, characterized in that discharge is prevented and a sustain pulse margin is increased.