JPH0265031A - Planar type display - Google Patents

Abstract

PURPOSE:To increase the luminance brightness and the contrast of a display, increase the response speed, and simplify a drive circuit with a low voltage by disposing a plurality of signal electrodes in a liquid crystal section and disposing a plurality of scanning electrodes in a plasma display panel section. CONSTITUTION:A discharge occurs between a pair of scanning electrodes 26 adjacent to each other among a plurality of scanning electrodes 26. When a liquid crystal 25 corresponding to a signal electrode 17 is in a light transmitting condition, the light emission at an intersection between the gap between the paired scanning electrodes 26 under the discharging condition and the signal electrode 17 is displayed with a brightness corresponding to the degree of transmission. Further, a linear discharge between the paired scanning electrodes 26 adjacent to each other is repeatedly moved in the direction of the arrangement of the plurality of scanning electrodes 26 and the linear discharge light is light-modulated according to the line signal level supplied to the plurality of signal electrodes 26. This makes it possible to increase the luminance brightness and contrast, increase the response speed, reduce the voltage of a drive circuit for the signal electrode 17, and simplify the drive circuit for the scanning electrodes 26.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel flat display device having a stacked liquid crystal panel section and plasma display panel section.

[Summary of the invention]

A first aspect of the present invention has a laminated liquid crystal panel section and a plasma display panel section, the liquid crystal panel section is provided with a plurality of signal electrodes, and the plasma display panel section has:
A plurality of scanning electrodes intersecting with a plurality of signal electrodes are provided,
The liquid crystal panel section is provided with a full-surface electrode that faces the plurality of signal electrodes with the liquid crystal in between, and three or more phases of scanning signals are supplied to the plurality of scanning electrodes in the plasma display panel section. By making the discharge occur between a pair of scanning electrodes adjacent to each other in the display, the brightness and contrast of the display is high, the response speed is fast, the driving circuit for the signal electrode can be a low voltage circuit, and the driving circuit for the scanning electrode is The circuit is made simple.

A second invention, in addition to the first invention, provides a phosphor layer in the plasma display panel section consisting of repeating striped phosphors of a plurality of emitting colors facing each gap between the plurality of scanning electrodes. As a result, color display is possible, the formation of the phosphor layer is easy, the power loss at the time of discharge rise is reduced, and the transistors forming the drive circuit can be displayed in color. This allows the withstand voltage to be lowered.

A third aspect of the present invention is an improvement on the second aspect of the present invention, in which a plurality of striped phosphors are arranged between phosphor layers of a plasma display panel section, each consisting of a plurality of scanning electrodes and striped phosphors of a plurality of emission colors. By providing a plurality of barrier ribs arranged between each of the plurality of scan electrodes and partitioning the discharge space between a pair of scan electrodes adjacent to each other among the plurality of scan electrodes, it is further possible to eliminate color mixture of displayed colors. be.

[Conventional technology]

Liquid crystal displays (LCDs) and plasma display panels (FDPs) are currently popular flat display devices.

[Problem to be solved by the invention]

Now, these LCDs and FDPs each have their own merits and demerits, and it is difficult to judge their superiority or inferiority. In other words, in terms of display visibility, PDPs are self-luminous, so they are easier to see than LCDs, but even LCDs can be made much easier to see by adding a backlight, but the thickness of the device is correspondingly large. becomes.

Also, when compared in terms of the price of the drive circuit, in the case of LCD, the voltage handled by the drive circuit is low, so it is cheaper, but FD
In the case of P, the voltage handled by the drive circuit is high, so it is expensive. However, in the case of a free-running type PDP, the structure of the drive circuit is simple, so the cost is correspondingly low.

Furthermore, when comparing the display efficiency (luminous efficiency) in the case of color display, the efficiency is low in the case of LCD because it uses a color filter, but the efficiency is high in the case of PDP because it does not use a color filter.

Therefore, the present invention aims to propose a display device that has both the advantages of LCD and PDP.

[Means to solve the problem]

A first aspect of the present invention has a stacked liquid crystal panel section (10) and a plasma display panel section (20), and the liquid crystal panel section (10) is provided with a plurality of signal electrodes (17),
The plasma display panel section (20) is provided with a plurality of scanning electrodes (26) intersecting with the plurality of signal electrodes (17), and the liquid crystal panel section (10) is provided with a plurality of signal electrodes (26) with the liquid crystal (15) in between. A full-surface electrode (13) facing the plasma display panel section (20) is provided, and scanning signals of three or more phases are supplied to the plurality of scanning electrodes (26) of the plasma display panel section (20). A discharge is caused between a pair of scanning electrodes that are adjacent to each other.

A second aspect of the present invention further provides a plasma display panel section (20) in the first aspect of the present invention. The phosphor layer (2
2) is provided.

In the third aspect of the present invention, in the second aspect of the present invention, the plasma display panel section (20) further includes a plurality of scan electrodes (
26) and striped phosphors R, G, B with multiple emission colors
A plurality of scanning electrodes (22) arranged between each of a plurality of striped phosphors R, G, B, and a plurality of scanning electrodes (22)
6), a plurality of partition walls (23) are provided to partition the discharge spaces between a pair of mutually adjacent scanning electrodes.

[Effect]

According to the first aspect of the present invention, discharge is performed between a pair of scan electrodes (26) adjacent to each other among the plurality of scan electrodes (26) of the plasma display panel section (20), and
The discharge portion moves repeatedly in one direction, while signals are supplied in parallel to a plurality of signal electrodes (17) of the liquid crystal panel section (10). Thus, when a discharge occurs between a pair of adjacent operating electrodes (26) among the plurality of scanning electrodes (26) and the liquid crystal (15) corresponding to the signal electrode (17) is in the light transmitting state, the plurality of scanning electrodes (26) The light emitted from the intersection of the signal electrode (17) and the gap between the pair of scan electrodes (26) in a discharged state is displayed externally with a brightness corresponding to its transmittance. Then, a plurality of scanning electrodes (26
) is repeatedly moved along the arrangement direction of the plurality of scanning electrodes (26), and the linear discharge light is transmitted to the plurality of signal electrodes (26).
), the light is modulated according to the level of the line signal supplied to the

According to the second aspect of the invention, furthermore, a plurality of scanning electrodes (26)
A discharge occurs between a pair of scanning electrodes (26) adjacent to each other, and a fireflash is generated based on the gap between the pair of scanning electrodes (26) in a discharged state and the discharge at the intersection of the plurality of signal electrodes (17). Each stripe phosphor of the light layer (22) generates fluorescence, and when the liquid crystal (15) corresponding to the signal electrode (17) is in a light transmitting state, each color of fluorescence is generated based on the discharge at the intersection. is displayed externally with a brightness that corresponds to its transparency. Then, a linear discharge between a pair of adjacent scanning electrodes among the plurality of scanning electrodes (26)
), and the light emitted by the phosphor due to the linear discharge is optically modulated according to the level of the line signal supplied to the plurality of signal electrodes (26).

According to the third aspect of the present invention, the discharge between the pair of scanning electrodes (26) is caused by the discharge between the pair of scanning electrodes (26) and the stripe phosphor next to the corresponding stripe phosphor R, G or B. There is no possibility of light emission, and color mixing of displayed colors is eliminated.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. 1 and 2 show the cross-sectional structure of the flat display device of this embodiment. An X, Y orthogonal coordinate system is provided on the display plane of this flat display device (the outline of which is a horizontally long rectangle). In this case, the horizontal direction of the display plane is the X direction, and the vertical direction is the Y direction. Thus, FIG. 1 shows a cross section of the display device taken along the X direction, and FIG. 2 shows a cross section taken along the Y direction. In FIGS. 1 and 2, in order to facilitate understanding, only the main parts are shown in cross-section with diagonal lines, etc., and other parts are omitted.

The structure of the display device (color display device) of this embodiment will be explained in detail below with reference to FIGS. 1 and 2. This display device consists of a liquid crystal panel section (10) and a plasma display panel section (20) which are laminated together, and the liquid crystal panel section (1o) side is the display side.

The liquid crystal panel section (10) utilizes the configuration of a backlit liquid crystal display device such as a TN type or STN type. Further, the plasma display panel section (20) utilizes the configuration of a self-scanning AC discharge type plasma display panel.

First, the structure of the liquid crystal panel section (10) will be explained. (15) is a liquid crystal, sealed in a flat space. On both sides of the liquid crystal (15), there are molecular alignment layers (14), (
16) are arranged. A transparent full-surface electrode (13) and a plurality of transparent stripe electrodes (signal electrodes) (17) are arranged so as to sandwich the liquid crystal (15) through these molecular alignment layers (14) and (16). . These full surface electrodes (13) and striped electrodes (17) are made of, for example, tin oxide, indium oxide, tin, or the like.

In this embodiment, the entire surface electrode (13) is arranged on the display side (this way, the terminal group faces upward, so
(This is advantageous in terms of handling), but the opposite is also possible.

The plurality of stripe electrodes (17) each have a constant width extending in the X direction, and are arranged in the X direction at predetermined intervals.

In the case of a liquid crystal display device, a plurality of other stripe electrodes perpendicular to the plurality of stripe electrodes (17) are arranged on the opposite side of the liquid crystal (15), but here, the corresponding one is a full-surface electrode ( 13), all stripe electrodes (17
) is faced.

A front glass plate (12) and a rear glass plate (
18) are arranged. In addition, these front glass plates (12
) and the rear glass plate (18) are provided with polarizing filters (11) and (19), respectively. In the case of the TN system, these polarizing filters (11) and (19) are used to create orthogonal polarizers. Configure.

Next, the structure of the plasma display panel section (20) will be explained. Reference numerals (26) denote a plurality of stripe electrodes (scanning electrodes), each of which has a constant width and extends in the X direction, and is arranged at predetermined intervals in the X direction. That is, the plurality of stripe electrodes (26) of the plasma display panel section (20) are arranged perpendicularly to the plurality of stripe electrodes (17) of the liquid crystal panel section (10). This stripe electrode (26) is formed on the back glass plate (27). The plurality of stripe electrodes (26) are
Covered with an insulating layer (25). Moreover, this insulating layer (25
) is protected against ion bombardment by 1'J (Mg
(consisting of O, etc.) are provided.

Note that the insulating layer (25) on the plurality of stripes (26) is omitted and the plasma display panel section (20) is
Although it is conceivable to configure it in a type, an AC type in which capacitors as loads are dispersed is preferable in order to realize uniform discharge light emission over a wide area.

(22) is a phosphor layer, and multiple stripe electrodes (26)
They are opposed to each other at a predetermined interval. This phosphor layer (22) is composed of repeating red, green, and blue striped phosphors R, G, and B with a constant width, and each striped phosphor is composed of a plurality of striped electrodes (26). They extend in the X direction and are arranged in the X direction so as to correspond to each gap.

As shown in FIG. 3, these striped phosphors R
. , generate fluorescent light of each color.

The ultraviolet rays generated by the discharge between a pair of stripe electrodes (26) stimulate the stripe phosphor corresponding to the gap between the adjacent pair of stripe electrodes (26), resulting in a mixture of displayed colors. In order to avoid the occurrence of
As shown in FIGS. 1 to 4, a plurality of stripe electrodes (2
6) and a plurality of striped phosphors R, G, B
A plurality of partition walls (23) extending in the X direction and arranged in the X direction are provided so as to separate each of the partition walls. These multiple bulkheads (
23) is provided in parallel with the stripe electrode (26), so the ultraviolet rays generated by the discharge are freely radiated in the direction in which the stripe electrode extends, thereby efficiently covering the phosphor layer (22). (It can emit light.

Note that if the pitch of the plurality of stripe electrodes (26) is large to some extent, such partition walls can be omitted. Further, in the flat display device according to the present invention, the phosphor layer (22) may be composed of a layer of phosphor of one color to constitute a monochromatic display device, or the phosphor layer (22) may not be provided. The phosphor layer consisting of three color striped phosphors (
22), it is also possible to set the emitted light color due to discharge to white and provide three color stripe filters on the liquid crystal panel section (10) side, but in such a case, the partition wall (23) is not necessary. Become.

A plurality of striped phosphors R, G, B of the insulating layer (25), the phosphor layer (22), and a plurality of partition walls (23) extend in the X direction and are arranged in the Y direction. An elongated discharge space (24) is formed. These discharge spaces (2
4) includes He.

A rare gas such as Ne5Xe is sealed.

In this case, as shown in FIG. 4, a communication hole (23h) is provided in a part of each partition wall (23) to create a discharge space (26) where a discharge occurs between an adjacent pair of striped electrodes (26).
Through this communication hole (23h), the charged particles generated in
The electrodes move to an adjacent discharge space so that discharge is likely to occur between adjacent pairs of stripe electrodes (26) in that discharge space (referred to as a briming effect).

(21) is a front glass plate, and in the figure, the above-mentioned phosphor layer (22) and partition wall (23) are formed on its lower surface side.

Then, each part of the liquid crystal panel section (10) and the plasma display panel section (20) is laminated and combined, and the periphery thereof is hermetically sealed to obtain a horizontally elongated substantially rectangular flat display device.

Next, the drive circuit of this display device will be explained with reference to FIG. As explained with reference to FIGS. 1 and 2, a plurality of stripe electrodes (1
7) and the stripe electrodes (26) of the plasma display panel section (20) are opposed to each other so as to be perpendicular to each other.

A pair of adjacent stripe electrodes of the plurality of stripe electrodes (26), that is, a stripe electrode (26a)
, (26b); (26b), (26c);...;
(26d), (26e),... In between, the phase changes sequentially and cyclically, for example, three phases (four or more phases are also possible, and the greater the number of phases, the better the stability of discharge transfer. However, the structure of the drive circuit becomes complicated instead, so the number of phases is set by balancing the two).
2. φ3 signal sources ea, eb, ec,...wo, on/off switches S W a , S W b , S W respectively
c.

Connect via... Then, at a certain point, if both the on-off switches SWa and SWb are turned on and the other on-off switches are turned off, a discharge occurs between a pair of adjacent stripe electrodes (26a) and (26b). , at the next point, the on-off switch SWb,
Both SWc are turned on, and the other on/off switches are turned off, so that the adjacent pair of stripe electrodes (26b),
(26c), and at the next point, both on-off switches SWc and SWd are turned on, and the other on-off switches are turned off, and the adjacent pair of stripe electrodes (26c) and (26d) are turned on. A discharge is generated in between, and this is repeated for each horizontal period of a video signal (television signal) to be described later, thereby performing self-scanning.

Since the discharge between a pair of adjacent stripe electrodes 1 (26) of the plurality of stripe electrodes (26) and the resulting light emission are constant, stable self-scanning is possible.

On the other hand, a plurality of stripe electrodes (
17), the pixel signals of each line signal of the video signal (television signal) VS are simultaneously supplied. . Then, the above-mentioned on-off switch S W a %SWb; SWb, S
Each line signal of the video signal is sequentially supplied to the plurality of stripe electrodes (17) in synchronization with the ON operation of Wc; SWc, SWd; -. As a result, the light transmittance of the portion of the liquid crystal (15) corresponding to the stripe electrode (17) is changed binary or continuously according to the voltage supplied to the stripe electrode (17), As a result, an image is displayed according to the image signals supplied to the plurality of stripe electrodes (17).

In the display device of the embodiment, a plurality of Xs that intersect with each other,
Instead of controlling the signal supply to both Y matrix electrodes, it is only necessary to switch the signal (scanning signal) to one of the plurality of stripe electrodes (26), so the reduction in contrast due to half selection, which is characteristic of liquid crystal displays, is avoided. There is almost no difference, and the response speed can be increased.

Next, another example of the drive circuit will be explained with reference to FIG. In FIG. 6, (26a),... (26
g), ... are the stripe electrodes of the plasma display panel section (20) mentioned above, and (26x) is the reset stripe electrode provided further above the stripe electrode 1 (26a) at the upper end thereof. .

A clock signal Φ is commonly applied to the stripe electrodes (26a), (26d), (26g), etc.
, are stripe electrodes (26b), (26e),...
Commonly, the clock signal Φ2 is connected to the stripe electrode (26c
), (26f)1, . . . are commonly supplied with a clock signal Φ3, respectively.

Note that a reset signal is supplied to the reset stripe electrode (26r) for each screen.

The clock signals Φ7, Φ2, and Φ3 are as shown in FIG.
A pulse whose level changes alternately between a low level and a high level with a short period τ, and the generation of the pulse is stopped for a period T every large period 3T (where T is a period equal to an integral multiple of the period τ). This signal is an intermittent pulse whose phase is sequentially shifted by τ/2, and the phase of the pulse generation stop period is shifted by a period T.

Therefore, for example, in a certain IT period d, clock signals Φ7 and Φ2 are applied between the stripe electrodes (26d) and (26e).
is applied, a glow discharge occurs during that time, and in the next IT period e-f, the stripe electrodes (26e), (26f)
Clock signals Φ2 and Φ3 are applied between them to generate a glow discharge, and in the next IT period fg, clock signals Φ3 and Φ3 are applied between stripe electrodes (26f) and (26g).
1 is applied, during which glow discharge occurs.

Note that display brightness can be adjusted by varying the duty of the pulse in the small period τ of the clock signals Φ1 to Φ3.

When the flat display device of the embodiment described above is compared with the conventional flat display device, it has the following advantages.

a) Compared to a conventional monochrome LCD, the display device of the embodiment has a faster response speed, a wider viewing angle, easier viewing, and higher contrast.

b) Compared to conventional monochrome FDPs, the display device of the embodiment uses self-scanning of the scanning electrodes [stripe electrodes (26) of the plasma display panel section (20)], which simplifies the structure of the drive circuit. Become.

C) Compared to conventional color liquid crystal displays, the display device of the embodiment eliminates the need for color filters, lowers the price, and can be made thinner than those with a backlight;
There is little color shift due to viewing angle.

d) Compared to a conventional color plasma display panel, the display device of the example combines a liquid crystal pulse section and a plasma display panel section, so the phosphor is in a stripe shape, so the phosphor is in the form of a dot matrix. Compared to the body, it is easier to align the electrodes, and because the discharge in the plasma display panel is done line by line rather than cell by cell, the power consumption at the start of discharge is low, and the drive circuit can be configured easily. Since a transistor with a low breakdown voltage can be used as the transistor for the drive circuit, the cost of the drive circuit can be reduced.

〔Effect of the invention〕

According to the first invention described above, the liquid crystal panel section and the plasma display panel section are stacked, the liquid crystal panel section is provided with a plurality of signal electrodes, and the plasma display panel section is provided with a plurality of signal electrodes that intersect with each other. A plurality of scanning electrodes are provided in the liquid crystal panel section, and a full-surface electrode is provided in the liquid crystal panel section facing the plurality of signal electrodes with the liquid crystal interposed therebetween. Since the display is provided with high brightness and contrast, the response speed is fast, and the drive circuit for the signal electrodes uses a low voltage. Only a few circuits are required, and the drive circuit for the scanning electrodes is simple.

According to the second aspect of the present invention, in contrast to the first aspect of the present invention, a phosphor layer is provided in the plasma display panel portion, which comprises repeating striped phosphors of a plurality of emitting colors facing each gap between a plurality of scanning electrodes. , it is possible to display in color, the phosphor layer can be easily formed, the power loss at the start of discharge is reduced, and the drive circuit can be configured even though the display is in color. The breakdown voltage of the transistor can be lowered.

According to the third aspect of the present invention, in contrast to the second aspect of the present invention, a plurality of striped fluorophores are provided between the phosphor layers of the plasma display panel section, which are composed of a plurality of scanning electrodes and striped phosphors of a plurality of emission colors. Since a plurality of partition walls are provided between each of the light bodies and partition the discharge space between a pair of adjacent scanning electrodes among the plurality of scanning electrodes, color mixing of displayed colors is further eliminated.

[Brief explanation of the drawing]

1 and 2 are sectional views of an embodiment of the present invention, and FIG.
4 is a cross-sectional perspective view of a portion of the display device of the example, FIG. 5 is a circuit diagram showing the drive circuit of the example, and FIG. 6 is a cross-sectional view of a portion of the display device of the example. FIG. 7 is a circuit diagram showing a part of another example driving circuit, and FIG. 7 is a timing chart for explaining the operation of the circuit shown in FIG. (10) is the liquid crystal panel part, (13) is the transparent entire surface electrode, (
15) is a liquid crystal, (17) is a transparent stripe electrode, (20
) is a plasma display panel section, (22) is a phosphor layer, (23) is a partition wall, and (26) is a stripe electrode.

Claims (1)

[Claims] 1. A liquid crystal panel section and a plasma display panel section are stacked, the liquid crystal panel section is provided with a plurality of signal electrodes, and the plasma display panel section is provided with a plurality of signal electrodes that intersect with the plurality of signal electrodes. A plurality of scanning electrodes are provided in the plasma display panel section, and a full-surface electrode is provided in the liquid crystal panel section facing the plurality of signal electrodes with the liquid crystal interposed therebetween. A flat panel display device, characterized in that a scanning signal is supplied to cause discharge to occur between a pair of adjacent scanning electrodes among the plurality of scanning electrodes. 2. The plasma display panel section is provided with a phosphor layer consisting of repeating striped phosphors of a plurality of emitting colors facing each gap between the plurality of scanning electrodes. flat display device. 3. Disposed between the phosphor layers of the plurality of scanning electrodes and the striped phosphors of the plurality of emission colors of the plasma display panel section, respectively between the plurality of striped phosphors; 3. The flat panel display device according to claim 2, further comprising a plurality of partition walls each partitioning a discharge space between a pair of adjacent scan electrodes among the plurality of scan electrodes.