JPH09245653A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly start and attenuate a discharge by containing a molecular kind, having second probability larger than first probability recoupling an ion of a atomic molecule and an electron by collision therebetween, in sealing gas of a discharge chamber in a display device using plasma. SOLUTION: In the case of discharge gas of single atomic molecule like rare gas, a charged particle at attenuation time of discharged plasma disappears by charge exchange mainly in a wall surface. On the other hand, in the case of containing molecular gas of large collision section al area like a molecule having two atoms or more, recoupling of charged particle at discharge ending time is quickly performed. Consequently, the number of scans in the same flame time can be increased, and contrast is also improved. Further, for instance, in a plasma address type liquid crystal display device, in a region except a display part, when a part 991 with a separating distance different between an anode electrode 305 a cathode electrode 306 is formed, the range of a conversion interelectrode distance of a discharge is broadened, so as to effectively make the discharge in rise up high speediness. Further, partly both the electrodes may be coated with an insulator layer 701.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using plasma, and more particularly to a plasma display and a plasma addressed liquid crystal display.

[0002]

2. Description of the Related Art In recent years, electronic information devices such as electronic calculators have been downsized. This is largely due to the miniaturization of electronic components represented by LSI. Arithmetic unit,
Main memory devices, auxiliary memory devices, etc. are rapidly miniaturized.

However, cathode ray tubes (hereinafter referred to as CRTs) are still widely used for display devices.
Since the CRT becomes large in principle, it cannot be used as a portable device, and the device is squeezing the space indoors at present.

As a means for solving such a problem, expectations for flat displays (hereinafter referred to as FPDs) are increasing. Various display devices such as liquid crystal displays and plasma displays have been proposed, some of which have been put into practical use and have become popular.

Similar to electronic information devices, in video devices such as televisions, the expectation of replacement of CRTs with FPDs is growing due to the trend toward high definition and large screens. In particular, it is difficult to install a large-screen TV at home with the depth of the CRT.

In order to realize a large-screen display device, a simple structure is important for practical use. Video equipment,
Matrix driving is indispensable because it is necessary to display an arbitrary image in both the information display device, but this requires several millions of pixels, and it is necessary to manufacture all pixels without defects.

Plasma display (hereinafter referred to as P
Plasma addressed liquid crystal display (hereinafter referred to as PALC) using plasma as a switching element.
Display devices have been proposed using plasma such as). In all of these, gas discharge is the main element of the display.

For example, in a PDP, 15 scan lines are selected.
A voltage of 0 to 300 V is applied to cause gas discharge. At this time, light emitted from excited atoms or molecules emitted from the discharge is used as a display light source. Alternatively, the fluorescent material can be applied to the discharge chamber in advance and excited by the ultraviolet rays emitted from the discharge to see the fluorescent light. The latter is the general operating principle of a color PDP.

On the other hand, the basic structure of PALC is similar to a liquid crystal display, and is a display device in which light transmission and blocking are selected by changing the orientation of liquid crystal. The orientation of the liquid crystal is controlled by charging the surface of the insulating substrate that seals the liquid crystal.

FIG. 12 is a sectional view schematically showing the structure of a conventional PALC.

PALC is a display device that electrically addresses a liquid crystal matrix using plasma. Corresponding to the scanning line of the CRT is an elongated discharge chamber 902 separated by a partition wall 901 having a width of several tens of μm. Inside the discharge chamber, a pair of anode electrode 903 and cathode electrode 90 are arranged in parallel with the discharge chamber.
4 is running.

A transparent insulating substrate 905, which is an upper partition of the discharge chamber, is disposed above the discharge chamber 902. Further, a liquid crystal layer 906 is enclosed between the liquid crystal layer 906 and a glass substrate 908 on which a signal line 907 formed of a transparent conductor is formed.

Anode electrode 903 and cathode electrode 904
A voltage is applied between and to cause gas discharge in the enclosed gas. Therefore, the discharge chamber 902 is filled with a gas such as a rare gas at an appropriate pressure. Upper partition 9 by plasma
05 Charged particles are supplied to the surface to change the state of charge-up.

The discharge chamber 902, which is a scanning line, and the anode electrode 90 are opposed to the discharge chamber 902 with the liquid crystal layer 906 interposed therebetween.
3, signal lines 907 are arranged so as to intersect the cathode electrodes 904 at right angles to each other. The signal line 907 is supplied with a voltage corresponding to the display desired to be written in the liquid crystal.

The amount of charge remaining on the upper barrier ribs 905 at the end of discharge depends on the potential of the signal line 907. A potential difference between the potential due to the charge amount and the potential of the counter electrode is applied to the liquid crystal 906. By controlling the voltage of the signal line 907 at the time of discharging, desired gradation display can be performed.

The discharge chamber 902 to be selected is the discharge chamber 9
A voltage of 150 to 300 V is applied to the discharge electrode belonging to No. 02 to cause gas discharge. Being in a discharged state, that is,
It is nothing but the selection of the discharge chamber 902 which is the scanning line.

In order to display an arbitrary image, it is necessary to perform line-sequential matrix driving and control the electrode voltage in time series. That is, when the nth scanning line is selected, a signal is given to the signal line according to the level to be written in the pixel belonging to the scanning line. After the writing of the nth scanning line is completed, a signal to be written to the pixel belonging to the n + 1th scanning line is given to the signal line, and the n + 1th scanning line is selected. The signal when selecting the (n + 1) th scanning line is n
It must be independent of the signal when the second scan line is selected. If another pixel is affected by a signal at the time of accessing a different scanning line, good contrast cannot be ensured and the image quality is degraded.

The partition walls separating the discharge chambers have a role of confining the discharges in the respective discharge chambers. This prevents charged particles in the plasma, that is, electrons and ions, from leaking from the discharge chamber and affecting the pixels of adjacent scanning lines.

Further, the anode electrode and the cathode electrode, which are the discharge electrodes, need to be electrically conductive enough to cause gas discharge. If the discharge can be started or ended in a short time, the time for accessing one scan line can be shortened, so that a display device with more scan lines can be designed and the image quality is improved. Therefore, it is desirable to shorten the time to reach the discharge starting voltage as much as possible, but it is desirable to lower the electric resistance of the discharge electrode.

In the AALC, the electric charge generated in the discharge chamber is attracted by the signal line and charged on the wall surface of the upper partition wall on the discharge chamber side, and the charge induced by the electric charge is accumulated on the liquid crystal layer side of the upper partition wall.

When the plasma discharge is stopped, the accumulated charges are held between the signal lines and the light modulation characteristics of the liquid crystal layer.

One problem with improving the characteristics of PALC is that the time response of the start and end of discharge is not always sufficiently fast. For example, when starting access to the nth scan line, the discharge for the (n-1) th scan line must be completely completed. Because if some charged particles remain in the discharge space corresponding to the (n-1) th scan line, the data of the signal line electrode prepared to be applied when accessing the nth scan line is used. Therefore, the (n-1) th liquid crystal voltage is affected. This leads to a reduction in image contrast,
You cannot get a good display.

In order to prevent the liquid crystal potential after the access from being influenced by the potential change of the signal line electrode, it is sufficient to wait until the charged particles completely disappear before moving to the next scanning line. However, this method requires a longer time to finish scanning one screen. That is, images that change in real time,
The display device is not suitable for displaying so-called moving images.

The essential solution is to make the decay of the charged particles more quickly after the end of the discharge.

Conventionally, it has been customary to use a rare gas as an enclosed gas for forming plasma. There is a limit to the rise and decay time of the discharge as long as the rare gas is used, and the display resolution that can be designed is the so-called VGA (640 ×
However, there is a problem in that a high-definition display, such as an XGA (1024 × 768) or HDTV display, cannot be realized. Also, VG
Even at a medium resolution of about A, there is a problem that crosstalk occurs and the contrast deteriorates.

In the conventional PDP and Ρ ALC structure, the width of the discharge chamber is often as large as 200 μm or more. This size is only 127 dpi (dots per inch), and it has become the standard resolution of low-cost printers, let alone the resolution similar to printed materials.
Not even pi. Therefore, in the future display, technology that realizes higher definition must be introduced.

Further, assuming that the number of scanning lines is n _AD and the frame time is t _fr , the access time per scanning line is 1 /
_{Limited to} (n _AD × t _fr ). In order to display a natural moving image, it is necessary to rewrite the screen 60 times or more per second. For example, to get the so-called XGA resolution, 1
The address time must be 21 μs or less.

The conventional discharge is 10 μs at the start and end of the discharge.
It takes a certain amount of time and it is difficult to completely complete the discharge within one frame time. Further, as a result, there is a problem that crosstalk occurs and the contrast is lowered. Further, there is a problem that the definition must be sacrificed to improve the contrast.

[0029]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. That is,
It is an object of the present invention to provide a high-performance display device in which the start and decay of discharge are quick. It is another object of the present invention to provide a high-definition display device which allows quicker selection of scanning lines and therefore has a large number of scanning lines. It is another object of the present invention to provide a display device with low crosstalk and high contrast.

[0030]

A display device of the present invention is a display device using plasma as a constituent element of a pixel, and is a discharge chamber and ions and electrons of a monatomic molecule enclosed in the discharge chamber. And a sealed gas containing a molecular species having a second probability higher than the first probability of collision and recombination with each other, and a voltage is applied to the sealed gas to generate a plasma state. And a voltage applying unit.

The display device of the present invention is a display device using plasma generated by applying a voltage to the gas sealed in the discharge chamber as a switching element or a light source, wherein the sealed gas is an ion of a monatomic molecule. And an electron collide and recombine with each other, and include a molecular species having a second probability larger than the first probability.

The display device of the present invention is a display device using plasma as a constituent element of a pixel, and includes a discharge chamber and
An enclosed gas containing a molecular species having vibrational energy and rotational energy, which is enclosed in the discharge chamber, and a voltage applying unit which is formed in the discharge chamber and applies a voltage to the enclosed gas to generate a plasma state. It is characterized by having.

Further, the display device of the present invention is a display device using plasma as a constituent element of a pixel, and includes a discharge chamber and
The gas filled in the discharge chamber and the first gas in the discharge chamber
Formed so as to have a first region separated by a first distance corresponding to the discharge start voltage and a second region separated by a second distance corresponding to the second discharge start voltage. And the second electrode.

The display device of the present invention is a display device using plasma as a constituent element of a pixel, and includes a discharge chamber,
Filled gas filled in the discharge chamber, and in the discharge chamber,
A pair of electrodes formed in substantially parallel to each other for applying a voltage to the enclosed gas to generate a plasma state;
And a thin film of diamond-structured carbon formed so as to cover the partial region.

The gas sealed in the discharge chamber is H ₂ , C.
O, CO ₂ , N ₂ , O ₂ , SF ₆ , NF ₃ , XeF ₂ ,
ArF ₂ , HeF ₂ , NeF ₂ , H ₂ O, CH ₄ , CF
₄ , C ₂ H ₂ , C ₂ H ₄ , and C ₂ N ₂ at least one kind is contained. Here, these gases show the constitution of elements, and the gas filled in the display device of the present invention includes the gas in which the elements constituting these gases are stable isotopes (for example, D2, ^13). C
O ₂ , ¹⁵ N ₂ , ¹⁴ N ¹⁵ N, etc.). It also includes using a gas composed of an element different from the natural isotopic composition.

Further, for example, a gas containing a part or all of a gas composed of a polyatomic molecule composed of one or more elements selected from nitrogen, oxygen, hydrogen and carbon may be used. The present invention can be applied to any display device using plasma as a constituent element of a pixel, such as a display device using plasma as a switching element or a light source, such as PDP or PALC, as long as the display device uses plasma.

That is, the present invention is to accelerate the start and decay of discharge of a display device using plasma such as PDP and PALC.

First, speeding up of plasma attenuation will be described. The display device of the present invention is a display device using a gas discharge as a main part or an auxiliary part of a display,
A second larger than the first probability that ions of monatomic molecules and electrons recombine with the gas that is the main body of the gas discharge.
A gas containing a molecular species having a probability of is used.
For example, a polyatomic molecule such as N ₂ has a large collision cross section with an electron and has a high electron consumption efficiency. The electrically neutral N ₂ molecule collides with an electron to be ionized, and the electron is consumed by a reaction such as N ₂ + e ⁻ → N ⁻ + N. Further generated N
^- it is, N ^{+ +} N ^- → N lose their charge by the reaction, such as ² + ^hν.

Further, while the total kinetic energy of a monoatomic molecule is translational energy, the kinetic energy of a polyatomic molecule includes vibrational energy and rotation energy in addition to translational energy. Therefore, the surplus energy at the time of collision with the electrons can be absorbed by the vibration, the rotation mode, etc., so that the electron consumption efficiency becomes high. The display device of the present invention uses a gas containing such a molecular species as an enclosed gas to quickly start up and attenuate the discharge.

A feature of the matrix type display device is that it can display arbitrary figures. On the other hand, since one screen is not constructed until the scanning of all the scanning lines is completed, it is necessary to continuously scan the entire screen in order to display a time-varying image. Moreover, it is necessary to set the time until the scanning of one screen is completed (referred to as one frame time) to be shorter than about 1/60 seconds. This is because the human illusion is used to display the moving image. If it takes more time to rewrite, the movement of the scanning line is recognized, and the image becomes flicker and difficult to see.

For a display utilizing gas discharge, 1
It is important to minimize the time from the start of access to the scan line to the end (hereinafter referred to as address time). This is because the rise and decay times of a normal gas discharge are long enough to be compared with the address time.

When one frame time is 1/60 second, the address time is determined according to the number of scanning lines. When the number of scanning lines is n, one address time is 1 / 60n second.

For example, the number of scanning lines is generally 480 as a monitor screen of a personal computer, but in this case, the address time is about 35 μs. In order to drive by the line-sequential method, it is necessary to start and end the plasma discharge within that time. The number of scanning lines tends to increase in order to meet the demand for higher definition, and there are examples of 1200 or more workstations. In this case, one address time is about 14 μs. In general, the time constant of rising and decay of discharge is 5 μs or more, and it is very difficult to completely complete the discharge within one address time.

In the PALC whose basic operation principle is to supply charged particles from plasma to be charged and hold the liquid crystal voltage by the charges, it is necessary to extinguish the charged particles promptly after the end of discharge. If the charge remains when the next scan line is accessed, the new signal affects the previous pixel column, that is, crosstalk occurs and the image quality deteriorates. Therefore, they are particularly susceptible to residual plasma particles.

The collision element process in plasma will be briefly described. The electrons in the plasma are accelerated by the applied electric field to obtain kinetic energy. When such electrons collide with gas atoms or molecules, ionization and excitation occur. When ionization occurs avalanche, it becomes a continuous supply source of charged particles and stable discharge occurs.

When a gas consisting of only monatomic molecules, for example, a discharge gas consisting of only a rare gas, is used, the disappearance process of charged particles after the voltage application to the discharge electrode is completed, that is, when the discharge plasma is attenuated is mainly on the wall surface. It is the charge exchange in.
It is known that the recombination of ions and electrons in the discharge plasma has a very small collision cross section. It is generally explained that the reason is that kinetic energy and momentum cannot be stored simultaneously in a two-body collision. Recombination in the other gas phase only occurs in the presence of a third body other than ions and electrons, ie neutral gas particles, for example, so that it is necessary that these three collide at the same time. The probability is very small.

On the other hand, in a collision between a molecular ion having an atomic number of two atomic molecules or more and an electron, the surplus energy can be absorbed by the vibrational energy and the rotational energy of the molecule in addition to the charge exchange on the wall surface. It has a collision recombination cross section much larger than the collision charge exchange of atomic molecules.

The present invention uses a molecular gas containing such a molecular species having a large collision cross-section as an enclosed gas. Therefore, the recombination of the charged particles is promptly performed after the discharge is completed. Therefore, the number of scanning lines can be increased in the same frame time. That is,
It is possible to provide a high-definition display suitable for displaying moving images.

Similarly, when comparing displays of the same definition, when the scan line is moved to the next scan line, the plasma of the previous scan line is completely extinguished, so that the pixel of the pixel corresponding to the next scan line is extinguished. Not affected by the signal.
That is, crosstalk is reduced. Also, an image with good contrast can be obtained.

Next, the speeding up of the rising of the plasma will be described.

In the display device of the present invention, the cathode electrode and the anode electrode, which are arranged in parallel in the discharge chamber and generate a plasma state by applying a voltage to the enclosed gas, are provided with different portions. . As a result, the electric field formed by the discharge electrodes forms a gradient in the discharge chamber belonging to one scanning line, and the discharge is started at the most suitable electric field.

The discharge breakdown condition when plasma is generated by the DC electric field is given by γ (e ^αd -1) = 1. Here, d is the distance between the electrodes, α is the electron ionization coefficient, and γ is the emission coefficient of secondary electrons emitted from the cathode electrode by the impact of ions. Further, the discharge start voltage Vst in the DC discharge is equal to the reduced interelectrode distance (reducede).
It is given by the following equation as a function of the product pd of the pressure p of the enclosed gas and the distance d between the electrodes. Vst = (Bpd) / {ln (pd) + ln (A / ln
(1 + 1 / γ))} where A = 1 / m, B = n / m, m is the mean free path of electrons at 1 Torr, and n is the mean ionization potential of gas. Therefore, there is an optimum voltage for the discharge start voltage, and the discharge start voltage changes due to the difference in the composition of the enclosed gas and the change in the composition due to the change over time of the display device.

The discharge start voltage in the high frequency electric field is influenced by the frequency of the high frequency applied in addition to the converted inter-electrode distance pd in the DC electric field, and can be displayed as Vst = F (pd, fd) (f is the frequency). The discharge starting voltage has an optimum voltage, and the discharge starting voltage changes depending on the composition of the enclosed gas, the composition of the display device with time, and the like.

In the present invention, the anode electrode and the cathode electrode are arranged so as to have a portion having a plurality of inter-electrode distances so as to cope with such a change in the discharge starting voltage. Therefore, the discharge is always started at the optimum voltage.

This portion may be formed outside the display area of the discharge chamber. Further, such a discharge trigger unit can be applied to a display device using plasma including AC type PDP, DC type PDP and PALC.

In the display device of the present invention, the electrodes in the discharge chamber are coated with carbon having a diamond structure. Here, carbon having a diamond structure (hereinafter simply referred to as “diamond”) may be not only a single crystal diamond but also a polycrystalline diamond, and further, these single crystal diamonds and polycrystalline diamonds are carried on a dielectric substrate. But it's okay. The formation of diamond on the surface of the cathode electrode facilitates the initiation of discharge. Further, the insulator coating assists the electric charge on the surface of the insulator to start the discharge, and a faster discharge can be obtained.

Further, the scanning line length Lscan of the discharge chamber is longer than Ldisp, which is the length of the display portion in the scanning line direction, by 1 mm or more, and the discharge chambers adjacent to each other in the non-overlapping portions of the discharge chamber and the display portion. You may make it provide the notch in the partition which connects.

The cutout portion draws in the charged particles generated in the discharge chamber corresponding to the previously selected scanning line, and facilitates the start of discharge in the discharge chamber to be selected next. Further, by setting the distance between the cutout portion and the display portion to be 1 mm or more, it is possible to sufficiently reduce the crosstalk between adjacent scanning lines, and it is also possible to perform sufficient discharge assist.

The above-mentioned triggers provided in the display device of the present invention for accelerating the start of discharge may be used alone or in combination. Further, it may be used in combination with the above-mentioned means for speeding up the decay of the discharge of the present invention. Of course, it may be used in combination with a conventional means for speeding up discharge initiation and decay.

[0060]

1 is a sectional view schematically showing a plasma-addressed liquid crystal display device as an example of the display device of the present invention.

Reference numeral 101 is a glass substrate, 102 is a discharge chamber which is a scanning line, 103 is a discharge electrode, 104 is an insulating thin plate such as glass, 105 is a liquid crystal layer, 106 is a transparent conductive film which is a data line, and 107 is a glass substrate. Is.

The discharge chamber 2 is formed parallel to one side of the glass substrate. In addition, the transparent conductive film 106 is formed in the discharge chamber 10.
It is oriented so as to be perpendicular to 2 (scan line), and this is hereinafter referred to as a signal line.

When a voltage of 200 V is applied to the pair of discharge electrodes 3, 200 T is set so that gas discharge starts in the discharge chamber.
Orr gas was filled. Here, a mixed gas of He and N ₂ was used as the gas.

A high voltage is sequentially applied to the discharge electrode 103, and 1
The scanning of one screen is completed in / 60 seconds. The total number of scanning lines was 600. A voltage corresponding to each pixel was sequentially applied to the signal line so as to display an image.

When the discharge starts, charged particles during the discharge enter the glass thin plate 104, and the amount of charge of the glass thin plate 104 depends on the voltage of the transparent conductive film 106 which is the signal line electrode. Therefore, the amount of inflow charges can be controlled by controlling the voltage applied to the signal line, that is, the voltage applied to the liquid crystal layer which is the light modulation layer can be controlled.

When the contrast was measured, it was 1:15.
0 was obtained.

For comparison, an experiment was conducted by filling an atomic gas, here, pure He gas, in an apparatus having the same structure. As a result, the measured contrast value was 1:40.

As described above, in the display device of the present invention, He
In addition, much better contrast can be obtained by using a fill gas for molecules having a large recombination cross section with electrons, such as a mixed gas of N ₂ .

The gas sealed in the discharge chamber is H ₂ , C.
O, CO ₂ , N ₂ , O ₂ , SF ₆ , NF ₃ , XeF ₂ ,
ArF ₂ , HeF ₂ , NeF ₂ , H ₂ O, CH ₄ , CF
A gas containing at least one member selected from the group consisting of ₄ , C ₂ H ₂ , C ₂ H ₄ , and C ₂ N ₂ may be used.

Here, an example in which the present invention is applied to PALC has been described, but the present invention may be applied to PDP regardless of AC type or DC type. In addition, PALC, PDP
Besides, it can be applied to a display device using plasma.

FIG. 2 is a diagram schematically showing the structure of an AC type PDP. A partition wall 202 is formed on a rear glass substrate 201, and a discharge chamber 206 is formed by these and a front glass substrate 205 on which a dielectric layer 203 and a protective film 204 are formed.
Are formed. Glass substrate 201 in discharge chamber 206
An address electrode 207 is formed on the upper side, and the signal electrode 2 is provided on the front glass substrate 205 side of the dielectric layer 203.
08 is formed. Then, a voltage is applied to a gas such as a rare gas sealed in the discharge chamber to generate a plasma state. In the PDP illustrated in FIG. 2, the phosphor 20 is placed in the discharge chamber.
9 is applied, and ultraviolet rays generated by plasma are converted into predetermined visible light by a phosphor to be used as display light.

Therefore, the same effect as that of the display device of FIG. 1 can be obtained by using the enclosed gas as described above.

FIG. 3 is a diagram schematically showing a PALC to which the present invention is applied. The discharge chamber 301, which is an address line, is formed by a glass substrate 302, partition walls 303, and upper partition walls 304. The discharge chamber 301 is filled with a gas that has a high probability of colliding with electrons and recombine as described above. Further, in the discharge chamber 301, a pair of anode electrodes 3 for generating a plasma state by applying an electric field to the enclosed gas.
05, the cathode electrode 306 is arranged in parallel with the extending direction of the discharge chamber. A liquid crystal layer 309 that is a light modulation layer is sandwiched between the upper partition 304 and a glass substrate 308 on which a transparent conductive film 307 that is a data line is formed.
The discharge chamber 301 is formed parallel to one side of the glass substrate, and the state is schematically shown in FIG. The discharge chamber 301, which is a scanning line, is formed so as to intersect the transparent conductive film 307, which is a data line, at a right angle.

FIG. 5 is a perspective view schematically showing a state in the discharge chamber of such a display device.

In the discharge chamber of FIG. 5, one auxiliary electrode 501 is provided for each discharge chamber. A power supply circuit is connected to each of the anode electrode 305, the cathode electrode 306, and the auxiliary electrode 501. In FIG. 5, a DC voltage source, a switch, and a resistor for limiting a discharge current are shown, but it goes without saying that these are notations for simply showing the operation principle, and actually, electronic parts such as a driving integrated circuit are shown. Composed of.

For comparison, a discharge experiment was conducted without applying any voltage to the auxiliary electrode 501. Discharge start time (where Imax is the final stable value of the discharge current flowing between the anode electrode 306 and the cathode electrode 305, Imax (1-
The time required to reach e ^-1 ) is defined as 10). In 100 trials, the discharge start time varied from 5 μs to 14 μs.

Next, a voltage was applied to the auxiliary electrode 501 and the same measurement was performed. A voltage is applied to the auxiliary electrode 501 and at the same time a voltage is applied to the discharge electrodes 305 and 306. The voltage application to the auxiliary electrode 501 was cut off after 5 μs, and thereafter the voltage was applied only to the discharge electrodes 305 and 306. The average discharge start time measured from the discharge current (current flowing between the electrodes 305 and 306) in this case is 6.5 μs, and the variation has a minimum value of 5.5 μs and a maximum value of 7.2 μs.
s, which was smaller than that of the comparative example.

When a gas having a large collision cross-sectional area as described above was used as the enclosed gas, the plasma decayed quickly.

Next, when a display using this electrode structure was prototyped and the display screen was observed, the contrast was 1:15 when the auxiliary electrode 501 was not used, but it was 1:60 when it was used. And was greatly improved.

FIG. 6 is a perspective view schematically showing another structure of the discharge chamber. In the discharge chamber illustrated in FIG. 6, the partition wall has a missing portion, and the discharge chambers 301 communicate with each other. A cutout 601 is provided at a position that does not overlap the display portion (see FIG. 4) of the partition wall 303 that separates the discharge chamber 301. The discharge electrode is connected to the external circuit.

The operation characteristics when there is no missing portion correspond to the characteristics when there is no auxiliary electrode 501 described in FIG. 5, and the average discharge start time is 10 μs, and the dispersion of the discharge start time is 100 trials. Is from 5 to 14 μs.

Next, the characteristics of the discharge chamber structure shown in FIG. 6 were measured. As a result, using the same electric circuit, the average value of the discharge start time was 6.2 μs, and the variation was a minimum value of 5.2 μs and a maximum value of 7.1 μs. Then, the discharge rises faster than the conventional example, and there is no variation.

When a gas containing a molecular species having vibrational energy and rotational energy as described above was enclosed in the discharge chamber 301 and a display device having the discharge chamber structure shown in FIG. 6 was produced as a prototype, the contrast was 1:55. , And showed excellent characteristics as compared with the comparative example. The positional relationship between the display portion of the prototype display and the discharge electrode chipped portion is as follows. Since the cutout portion and the display portion do not overlap with each other and the shortest distance between the cutout portion and the display portion is 0.6 mm, there is no problem with the uniformity of the screen. For the purpose of comparison, a prototype of a display in which the shortest distance between the cutout portion and the display portion was 0.05 mm was produced, and the contrast at the edge of the screen was not good, resulting in an image with insufficient uniformity.

FIG. 7 is a perspective view schematically showing another structure of the discharge chamber. The discharge electrodes 305 and 306 were covered with an insulator layer 701 in a region other than the display portion of the display device. The discharge electrodes 305 and 306 are connected to an external circuit.

The operating characteristics when the insulator layer is not formed are as follows.
This corresponds to the characteristic in the case where there is no auxiliary electrode 501 having the discharge chamber structure illustrated in FIG. 5, and as described above, the average value of the discharge start times is 10 μs, and the dispersion of the discharge start times is 5 μs in 100 trials. Up to 14 μs.

Next, when the characteristics of the discharge in the discharge chamber illustrated in FIG. 7 were measured, using the same electric circuit as described above, the average value of the discharge start time was 6.8 μs, and its variation was the minimum value of 5.5 μs. The maximum value was 7.8 μs, and the start time was shorter than that of the conventional example, and there was no variation.

When a display according to this example was manufactured as a prototype, the contrast was 1:40, which was far superior to that of the comparative example.

Further, when a diamond thin film 702 was used instead of the above-mentioned insulator film 701 to cover the discharge electrode, a faster response was realized, and an average value of the discharge start time of 2.2 μs was obtained ( (Figure 8).

FIG. 9 is a perspective view schematically showing another structure of the discharge chamber. In a region other than the display portion of the display device, portions 991 having different discharge electrodes 305 and 306 are formed. FIG. 10 is an enlarged view of a portion 991 in which the discharge electrodes 305 and 306 have different spacings, and FIG. 11 is a modification thereof. In FIG. 9, FIG. 10, and FIG. Although the discharge electrodes are formed so as to spread toward the discharge electrodes, the discharge electrodes may be formed so that the widths of the discharge electrodes are different from each other, and the distance between the electrodes may be different. Further, the spacing between the discharge electrodes may be changed discontinuously. It is more preferable to form it so as to change continuously.

As described above, the portion 99 where the discharge electrodes 305 and 306, which are the trigger portions for starting the discharge, have different spacings.
Since 1, the range of the distance between the converted electrodes of the discharge is expanded,
Even when the composition of the enclosed gas, the isotope ratio composition, or the pressure changes, the discharge can be effectively started.

The operating characteristics in the case where the trigger portion is not formed correspond to the characteristics in the case where the auxiliary electrode 501 is absent, as described in the example of FIG. Therefore, the average discharge start time is 10μ
The variation of the discharge start time is 5 to 14 μs in 100 trials.

Next, the discharge chamber 301 having the electrodes shown in FIG. 10 is formed.
When the characteristics of the discharge were measured, the average value of the discharge start time was 4.8 μs and the variation was the minimum value of 4.2 μs and the maximum value of 55 μs using the same electric circuit. The time was shortened and there was no variation.

When a display device provided with the discharge chamber 301 having the electrodes illustrated in FIG. 10 was prototyped, the contrast was 1:80, which was far superior to the comparative example.

The examples described above are effective alone, but when they are used in combination, more excellent effects are shown. For example, using the auxiliary electrode 501 illustrated in FIG. 5,
Further, the auxiliary electrode 501 may be covered with a diamond thin film. Further, for example, by enclosing a gas containing a molecular species having a large cross-sectional area of collision with electrons in the discharge chamber illustrated in FIGS. Can be obtained. Therefore, the scanning time can be shortened and high-definition display can be obtained.

[0095]

As described above, according to the present invention,
It is possible to obtain a display device in which discharge rises and decays at high speed. Therefore, the scanning time can be shortened, and display quality with less crosstalk and high contrast can be obtained. Further, if the contrast is the same, it is possible to obtain a more flicker-free display.

Further, since the number of scanning lines can be increased, a higher definition display device can be obtained.

Further, the display device of the present invention can stably start the discharge even if the composition (including the isotope ratio composition) of the enclosed gas and the pressure change due to changes over time. Further, the margins of the electrode spacing, the enclosed gas pressure, and the enclosed gas composition at the time of manufacture are widened, and the productivity is improved.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an example of a display device (PALC) to which the present invention is applied.

FIG. 2 is a diagram schematically showing the structure of an AC PDP.

FIG. 3 is a diagram schematically showing a PALC to which the present invention is applied.

FIG. 4 is a diagram schematically showing an arrangement of discharge chambers.

FIG. 5 is a perspective view schematically showing a state inside the discharge chamber.

FIG. 6 is a perspective view schematically showing a state in the discharge chamber.

FIG. 7 is a perspective view schematically showing a state inside the discharge chamber.

FIG. 8 is a perspective view schematically showing a state inside the discharge chamber.

FIG. 9 is a perspective view schematically showing a state inside the discharge chamber.

FIG. 10 is an enlarged view showing an electrode end portion.

FIG. 11 is an enlarged view showing an electrode end portion.

FIG. 12 is a sectional view schematically showing a conventional PALC.

[Explanation of symbols]

101 ... Glass substrate, 102 ... Discharge chamber, 103 ...
Discharge electrode 104 ... Insulating thin plate, 105 ... Liquid crystal layer, 106 ...
..., transparent conductive film 301 ... discharge chamber, 302 ... glass substrate, 303 ...
Partition wall 304 ... Upper partition wall, 305 ... Anode electrode, 306
...... Cathode electrode 307 …… Transparent conductive film, 308 …… Glass substrate, 309
...... Liquid crystal layer 501 …… Auxiliary electrode 601 …… Missing part 701 …… Insulator coating 702 …… Diamond coating

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01J 17/20 H01J 17/20

Claims (5)

[Claims] 1. A display device using plasma as a constituent element of a pixel, comprising: a discharge chamber and ions of a monoatomic molecule and electrons colliding with each other in an ion state enclosed in the discharge chamber, A sealed gas containing a molecular species that recombines by colliding with electrons with a second probability higher than the first probability of bonding, and a voltage is applied to the sealed gas to generate a plasma state. A display device comprising: 2. A display device using plasma as a constituent element of a pixel, comprising: a discharge chamber, an enclosed gas containing a molecular species having vibrational energy and rotational energy, which is enclosed in the discharge chamber, A display device, comprising: a voltage applying unit that is formed in a chamber and applies a voltage to the enclosed gas to generate a plasma state. 3. A display device using plasma as a constituent element of a pixel, comprising: a discharge chamber, a fill gas filled in the discharge chamber, and a first discharge start voltage corresponding to a first discharge start voltage in the discharge chamber. A first electrode and a second electrode that are formed to have a first region that is separated by a distance of 1 and a second region that is separated by a second distance that corresponds to a second discharge firing voltage; A display device comprising: 4. A display device using plasma as a constituent element of a pixel, wherein a discharge chamber, a filling gas filled in the discharge chamber, and a plasma by applying a voltage to the filling gas in the discharge chamber. A display device comprising: a pair of electrodes formed substantially parallel to each other to generate a state; and a thin film made of carbon having a diamond structure formed so as to cover a partial region of the pair of electrodes. 5. The filling gas is H ₂ , CO, CO ₂ , N
₂ , O ₂ , SF ₆ , NF ₃ , XeF ₂ , ArF ₂ , He
F ₂ , NeF ₂ , H ₂ O, CH ₄ , CF ₄ , C ₂ H ₂ ,
5. The display device according to claim 1, which contains at least one member selected from the group consisting of C ₂ H ₄ and C ₂ N ₂ .