JPS5947861B2 - Plasma display panel with alarm display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plasma display panel, and more particularly to a plasma display panel with an alarm display that can indicate the end of its life.

Plasma display panel F as a display device that displays characters, numbers, symbols, etc. by selecting multiple electrodes
This panel, in which DP is widely used, has a finite lifespan, and if used for a long period of time, it will no longer be able to achieve normal display functions.

However, this lifespan differs slightly depending on each panel, and it is impossible to know it in advance.

Furthermore, the plasma display panel has an X-Y dot matrix type in which display electrodes are arranged linearly,
There is a segment type in which the display electrodes are arranged, for example, in a Japanese character shape, that is, in a segment shape.

- In particular, segment-type plasma display panels display letters, numbers, and symbols by decoding input binary signals and then selectively emitting light from segments corresponding to each input signal using matrix diode gates. However, even if a normal electrical signal corresponding to the input signal is applied to the display panel, some problem may occur within the display panel, and even if a particular segment is electrically selected, If the discharge light does not emit light, an erroneous display will occur.

For example, if the number display is displayed in 7 segments, even if the input signal is 8 and the electrical signal applied to the display panel is 8, the life of the center segment of the CI has expired and no light is emitted. said the mouth.

There are many cases where display devices are used in important places such as displaying money transfers, and the inconvenience caused by the above-mentioned incorrect display is extremely serious.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a plasma display panel in which it is possible to indicate in advance that the display life has expired.

Another object of the present invention is to provide a plasma display panel that can eliminate inconveniences caused by erroneous display.

According to the present invention, an alarm electrode for alarm display is provided independently of the display electrode, and the plasma display panel has a reduced amount of discharge-resistant material so that the life of the alarm electrode is shorter than the life of the display electrode. can be obtained.

That is, according to the present invention, in a plasma display panel equipped with a first display electrode that displays characters, numbers, symbols, etc. by selecting a plurality of electrodes,
When the first display electrode is driven, a second display electrode is provided which is driven to be lit at all times, and the amount of discharge-resistant material on the second display electrode is made smaller than the amount of discharge-resistant material on the first display electrode. A plasma display device with an alarm display characterized in that the life of the second display electrode is shorter than the life of the first display electrode.
A display panel is obtained.

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a block diagram of a conventional plasma display device.

The input signal is input to a 7-segment decoder 1, and within this 7-segment decoder 1, the input 4-bit signal is decoded into a 7-segment signal corresponding to a display segment and sent to a drive circuit 2, which drives the plasma display. A signal stepped up to the voltage required to drive the plasma display panel 3 is supplied to the segment side of the plasma display panel 3.

On the other hand, a signal synchronized with these signals is supplied to the digit driver 4.

A plasma display panel performs display by utilizing the fact that only the segments to which signals on the digit side of the signals on the segment side are simultaneously applied discharge and emit light.

The aging of the discharge starting voltage of a plasma display panel varies depending on the amount of the discharge-resistant material used in the material in contact with the discharge of the plasma display panel, and as the amount of the discharge-resistant material increases, the aging of the discharge starting voltage becomes smaller.

Referring to FIG. 2, the plasma display panel is
An electrode 22 is formed on a glass plate 21, a glass film is coated on the electrode 22, and an MgO film 24 is further coated on the glass film as a discharge-resistant material.The two glass plates are arranged to maintain a discharge space 25. The discharge space 25 has a structure in which a dischargeable gas such as Ne is sealed in the discharge space 25.

In a plasma display having such a structure, the space in which the electrodes 24 face each other forms a discharge cell, and the aging of the discharge starting voltage of each cell varies depending on the amount of the discharge-resistant material 24 corresponding to each cell. Ru.

Figure 3 shows each discharge cell in a plasma display having a plurality of discharge cells when the amount of discharge-resistant material corresponding to one discharge cell is set to - the amount of discharge-resistant material in other discharge cells. This figure shows the change in discharge starting voltage over time.

In FIG. 3, the discharge starting voltage of a discharge cell group having the same amount of discharge-resistant material varies over time with a distribution as shown in 31 in FIG. 3 due to the cap of each discharge cell in the discharge cell group and other reasons. change with.

However, as shown by 32 in FIG. 3, the discharge starting voltage of the above-mentioned discharge cells having - of the discharge-resistant material of those cell groups is completely different from the aging change of the discharge starting voltage of the discharge cell group, and is short-lived. rises with time.

When this plasma display panel is driven with a voltage Vo, a discharge cell with a negative discharge capacity reaches a discharge start voltage Vo in a time indicated by t, and does not discharge thereafter.

On the other hand, the discharge starting voltage at time t1 of the discharge cell having a normal amount of discharge-resistant material is lower than Vo, and the discharge starting voltage reaches Vo in 12 hours.

One aspect of the present invention is a plasma display panel that utilizes such properties to ensure that the display is normal.

FIG. 4 shows an embodiment of the present invention.

That is, a display cell group 41 and an alarm segment 42
are provided in the same plasma display 43, the discharge resistant material amount of the display cell group 41 is made larger than that of the alarm segment, and the drive circuit 45. is provided in the alarm segment.
If the frequency and voltage value of the driving voltage applied through the drive circuit 44 are made the same as the frequency and voltage value of the voltage applied to the display cell through the drive circuit 46 and 47, the shift alarm will be suppressed for the above-mentioned reason. If the discharge starting voltage of the display cell becomes higher than the drive voltage in a shorter time than the display cell, no discharge will occur.

Therefore, it can be determined whether the display cell is operating normally or not based on the lighting and non-lighting of the alarm discharge cell.

That is, while the alarm cell is lit, the display cell is normal, and as long as the alarm cell is not lit, the display cell is t2-t1.
If you replace the plasma display panel in time, you can always get a normal display.

In the above description, the case of a segment type plasma display panel has been described, but it goes without saying that the same effect can be achieved with an XY dot matrix type panel.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a conventional plasma display device, Fig. 2 is a cross-sectional view of a conventional plasma display panel, and Fig. 3 is a graph showing changes in discharge starting voltage over time and discharge-resistant materials in plasma display panels. FIG. 4 is a block diagram of a plasma display device showing an embodiment of the present invention.

Claims (1)

[Claims] 1 By selecting multiple electrodes, letters, numbers,
A plasma display device equipped with a first display electrode for displaying symbols, etc.
In the display panel, a second display electrode is provided which is driven to be lit at all times when the first display electrode is driven, and the amount of discharge-resistant material on the second display electrode is set to be equal to the amount of discharge-resistant material on the first display electrode. A plasma display panel with an alarm display, characterized in that the life of the second display electrode is shorter than the life of the first display electrode by reducing the amount of discharged material.