JPH05241134A - High polymer dispersion type liquid crystal display element - Google Patents

Abstract

(57) [Abstract] [Purpose] To simplify the structure of a reflection type polymer dispersion type liquid crystal display element for performing fixed pattern display, to reduce the thickness and cost. [Structure] Polymer dispersed liquid crystal layer 3 and window frame plates, printed letters / design plates, UV cut plates, antiglare plates arranged above and below upper substrate 1 and lower substrate 2 sandwiching this polymer dispersed liquid crystal layer 3. Alternatively, the composite front plate 6 or the composite window frame front plate 8 or the composite back plate 9 in which a plurality of predetermined functions of the reflection plate and the back plate are made common. [Effect] The element structure can be simplified, the manufacturing process can be simplified, and the cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device using a polymer-dispersed liquid crystal, and particularly, to simplify the device structure as a reflective liquid crystal display device for displaying a fixed pattern,
The present invention relates to a polymer dispersion type liquid crystal display device having improved reflectivity and visibility.

[0002]

2. Description of the Related Art Conventionally, a polymer dispersed liquid crystal display device in which liquid crystal droplets are dispersed in a polymer material has been known. In this type of liquid crystal display device, a polymer-dispersed liquid crystal thin film (usually about 5 to 20 μm thick) consisting of fine capsules in which liquid crystal is wrapped with a polymer material is sandwiched between transparent electrodes, and a voltage is applied between the electrodes. It is opaque when there is no light (off state) (it absorbs light when a dichroic dye called guest-host mode is used), but it is opaque when a voltage of an appropriate magnitude is applied (on. State) It has the property of becoming transparent.

This polymer-dispersed liquid crystal display device does not require a polarizing plate as compared with a conventional liquid crystal display device using liquid crystals (twist nematic: TN, super twist nematic: STN, etc.). Therefore, it is possible to obtain a bright display with a wide field of view, and it is not necessary to arrange liquid crystal molecules regularly, so that an alignment film is not necessary. Techniques relating to such a polymer-dispersed liquid crystal display device and a liquid crystal display device using the same are already known, and are disclosed in, for example, U.S. Pat. No. 4,435,047.

FIG. 5 is a schematic external view for explaining a reflective liquid crystal display device using a polymer dispersed liquid crystal according to the prior art, in which 20 is a reflective liquid crystal display device and 30 is a display pattern. The reflection type liquid crystal display element 20 shown in the figure is for operating instructions of audio equipment and video equipment, for example, and the display pattern 30 is recording 31, reproduction 32, still reproduction 33, fast forward 34, rewind 35, stop. 35 is for displaying. When mounting on the above audio equipment and video equipment,
A switch mechanism such as a touch plate is installed on the front surface or the back surface of the reflective liquid crystal display element 20.

Needless to say, the reflective liquid crystal display element 20 is used only for its display function. FIG. 6 is a schematic cross-sectional view taken along the line AA of FIG. 5 for explaining the general structure of a reflective liquid crystal display device according to the prior art, in which 1 is an upper substrate, 2 is a lower substrate, and 3 is a polymer. A liquid crystal layer made of dispersed liquid crystal, 11 is an upper electrode, and 21 is a lower electrode reflector. In the figure, various components described later are omitted.

The upper substrate 1 and the lower substrate 2 are made of glass or P.
It is composed of a transparent plate made of a plastic plate such as ET, PES or polycarbonate, and indium-titanium-oxide (ITO) is formed on the surfaces of the upper substrate 1 and the lower substrate 2.
An upper electrode 11 and a lower electrode 21 to which a thin film or the like is attached are formed. At least one of the upper electrode 11 and the lower electrode 21 has a shape corresponding to the display pattern 30 (in the figure, the display pattern is formed on the lower electrode).

Between the upper substrate 1 and the lower substrate 2, a polymer-dispersed type composed of fine capsules (liquid crystal droplets) in which liquid crystal is wrapped with a polymer material in contact with electrodes formed on these substrates. The liquid crystal layer 3 is sandwiched. FIG. 7 is a developed perspective view illustrating a detailed structure of the reflective liquid crystal display element shown in FIGS. 5 and 6.

In the figure, the same reference numerals as those in the above figures correspond to the same parts, and 4 is a window frame plate which is formed of paper or plastic film. A window hole 41 is provided in a portion corresponding to the display pattern 30, and the display pattern 30 can be seen through the window hole 41. On the window frame plate 4, there are characters or patterns printed on the front surface or the back surface.
Transparent film characters that are also transparent films that work as patterns and printed characters and patterns in a transparent film on which patterns are printed (hereinafter simply referred to as pattern plates) 6-1 and protect the liquid crystal material that constitutes the liquid crystal layer 3 from decomposition by ultraviolet rays UV protection plate 6-2 for
An anti-glare plate 6-3 is arranged to deluster the surface of the display element and reduce the light directly reflected from the surface.

Reference numeral 5 is a reflector, which is made of paper or plastic and has a fluorescent color printing section 51 provided in a portion corresponding to the display pattern 30. 7 is a back plate, which is formed of a plastic film or the like. In addition, various transparent electrode patterns 2 including the lower electrode 21 on the lower substrate 2
1-1 also includes an unillustrated lead wiring pattern and the like. Further, the upper electrode 11, the upper surface of the lower electrode 21, S _i O
It may be protected by an insulating film such as _x .

In such a structure, a liquid crystal layer 3 made of a polymer dispersed liquid crystal material is provided between the upper substrate 1 and the lower substrate 2.
Is narrowed.

[0011]

The polymer-dispersed liquid crystal display device 20 according to the prior art described above does not require a polarizing plate or an alignment film, and scatters and transmits light (in the case of a guest host containing a dye, it does not emit light). A TN that uses a polarizing plate because it displays a pattern using two states (absorption and transmission).
Since it has a feature in terms of image quality that a brighter display can be obtained than a liquid crystal display element of a liquid crystal display type or an STN type, a backlight is not required as a reflection type, and thinning and low power consumption can be achieved.

However, since a large number of plate materials such as the window frame plate 4, the pattern plate 6-1, the ultraviolet ray blocking plate 6-2 and the antiglare plate 6-3 are used, the element structure becomes complicated and the manufacturing process However, it is complicated and requires precise positioning work between the above plate materials, and is economically disadvantageous. The purpose of the present invention is to
It is an object of the present invention to provide a polymer-dispersed liquid crystal display device having a simplified structure by solving the above-mentioned problems in the prior art.

[0013]

In order to achieve the above-mentioned object, in a fixed pattern display type reflection type display device using a polymer dispersed liquid crystal according to the present invention, a window frame which is a component of the device. Easy to manufacture by simplifying the structure of the plate, design plate, UV cut plate, anti-glare plate, or reflector plate, back plate,
And the feature is that the brightness is further improved.

That is, according to the present invention, a polymer-dispersed liquid crystal in which a polymer-dispersed liquid crystal layer 3 is interposed between an upper substrate 1 on which an upper electrode 11 is formed and a lower substrate 2 on which a lower electrode 21 is formed. In the display element, a window frame plate 4 having window holes 41 corresponding to a predetermined display pattern 30 on the outer surface side of the upper substrate 1.
And a reflection plate 5 having a fluorescent color printing portion 51 corresponding to the display pattern on the outer surface side of the lower substrate 2 while laminating a composite front plate 6 having an ultraviolet blocking action and an antiglare action in this order, The back plate 7 and the back plate 7 are laminated in this order.

The function of the reflection plate 5 having the fluorescent color printing portion 51 corresponding to the display pattern and the function of the back plate 7 are integrated to function as the reflection plate having the fluorescent color printing portion corresponding to the display pattern. You may laminate the composite back plate 9 which has. In addition, the present invention provides the upper substrate 1 on which the upper electrode 11 is formed.
In a polymer dispersed liquid crystal display device in which a polymer dispersed liquid crystal layer 3 is interposed between a lower substrate 2 and a lower substrate 2 on which a lower electrode 21 is formed, a predetermined display pattern 30 is formed on the outer surface side of the upper substrate 1. The composite window frame front plate 6 having the function of the window hole, the function of blocking ultraviolet rays and the function of preventing glare is laminated, and the fluorescent color printing portion 51 corresponding to the display pattern 30 is provided on the outer surface side of the lower substrate 2. The reflecting plate 5 and the back plate 7 are laminated in this order.

The function of the reflector 5 having the fluorescent color printing portion 51 corresponding to the display pattern and the function of the back plate 7 are integrated to function as the reflecting plate having the fluorescent color printing portion corresponding to the display pattern. You may laminate the composite back plate 9 which has. The display pattern 30 can be formed by patterning at least one of the upper electrode 11 and the lower electrode 21, but when the display of all of the display elements is simply turned on / off, the patterning of this electrode is particularly necessary. do not do.

Further, since the polymer-dispersed liquid crystal layer 3 is flexible, a liquid crystal display element having a curved surface can be obtained by forming each of the above-mentioned substrates and other constituent members with a flexible material. Obtainable.

[0018]

With the above-described structure of the present invention, the structure of the liquid crystal display device is simplified, and the manufacturing process can be simplified to provide a high-precision polymer dispersion type liquid crystal display device. Can also be applied as a non-planar liquid crystal display means according to the shape of the mounting portion surface of the mounting target.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a developed perspective view illustrating a polymer dispersed liquid crystal display device according to a first embodiment of the present invention, in which 1 is a transparent upper substrate made of glass or plastic, and 11 is an upper electrode formed on the upper substrate 1. 2 is a transparent lower substrate similar to the upper substrate, 21 is a lower electrode formed on the substrate 2, and the lower substrate 21 is patterned into a predetermined display pattern.

3 is a polymer dispersed liquid crystal layer, 4 is a window frame plate having a window hole 41 corresponding to the above display pattern, 5 is a reflector plate having a fluorescent color printing portion 51 corresponding to the above display pattern, 6 is a composite front plate having a pattern board function, an ultraviolet ray cutting function for protecting the liquid crystal layer from ultraviolet rays, and an antiglare function, and 7 is a back plate. The window frame plate 4 and the composite front plate 6 are laminated on the upper substrate 1 side in this order, and the reflector 5 and the back plate 7 are laminated on the lower substrate 2 side in this order.

Light incident from the composite front plate 6 side reaches the window frame plate 4, the upper substrate 1, the liquid crystal layer 3, the lower substrate 2, and the reflection plate 5,
The light reflected by the reflection plate 5 is emitted from the composite front plate 6 in the reverse order of the above. At this time, the upper electrode 11 and the lower electrode 21
The emitted light has a display pattern due to the light valve action of the liquid crystal in the display pattern portion corresponding to the pattern of the lower electrode 21 according to the voltage applied between them. The emitted light becomes colored light corresponding to the color of the fluorescent color printing portion 51 formed on the reflection plate 5.

According to the present embodiment, each function of the pattern plate, the ultraviolet ray blocking plate and the antiglare plate described in FIG.
This can be achieved with a single composite front plate, the element structure can be simplified, and the element can be thinned. 2 is a developed perspective view illustrating a polymer dispersed liquid crystal display device according to a second embodiment of the present invention, wherein the same reference numerals as those in FIG. 1 correspond to the same portions, and 9 is a composite back plate.

In this embodiment, the reflection plate and the back plate in the embodiment described in FIG. 1 are integrated to form a composite back plate 9, and a fluorescent color printing section 51 is provided on a plate material such as a plastic film. ing. According to this embodiment, the device structure can be simplified and the device can be made thinner as in the previous embodiments.

FIG. 3 is a developed perspective view illustrating a third embodiment of the polymer dispersed liquid crystal display device according to the present invention.
The same reference numeral corresponds to the same portion, and 8 is a composite window frame plate. In the figure, the pattern board 6-1 explained in FIG. 7 is integrated with the ultraviolet ray blocking plate 6-2 and the antiglare plate 6-3 to form a composite having the function of the pattern board and the ultraviolet ray cutting function and the antiglare function. The window frame plate 8 is used.

The composite window frame plate 8 is obtained by subjecting the front surface or the back surface of the plate material to an opaque treatment by printing with a black ink or the like except the portion corresponding to the window hole 41 in FIG. Do the printing on a surface different from the printing surface of
Either the printing may be performed on the same surface before printing the characters or the design, or any method may be used. According to this embodiment, the device structure can be simplified and the device can be made thinner as in the previous embodiments.

FIG. 4 is a developed perspective view illustrating a fourth embodiment of the polymer dispersed liquid crystal display device according to the present invention.
The same reference numeral corresponds to the same portion, and 9 is a composite back plate.
In the same figure, in the structure of the embodiment of FIG. 3, a composite back plate 9 having the functions of the reflection plate 5 and the back plate 7 is provided, and the fluorescent color printing section 51 is provided on the plate material constituting the back plate. It is a thing.

According to this embodiment, the device structure can be further simplified and the device can be made thinner as in the above-described embodiments.

[0028]

As described above, according to the present invention, the window frame plate, the printed characters, and the like necessary for constructing the liquid crystal display device are provided.
It is possible to use a pattern plate, an ultraviolet ray blocking plate, an antiglare plate, and a plate such as a reflection plate and a back plate in common, and to simplify the structure of a reflective polymer dispersed display device for displaying a fixed pattern and display the same. It is possible to make the element thin, shorten the image process, and realize low cost.

[Brief description of drawings]

FIG. 1 shows a first polymer dispersed liquid crystal display device according to the present invention.
It is a development perspective view explaining an example.

FIG. 2 shows a second example of the polymer dispersed liquid crystal display device according to the present invention.
It is a development perspective view explaining an example.

FIG. 3 is a third example of the polymer dispersed liquid crystal display device according to the present invention.
It is a development perspective view explaining an example.

FIG. 4 is a fourth example of the polymer dispersed liquid crystal display device according to the present invention.
It is a development perspective view explaining an example.

FIG. 5 is a schematic external view illustrating a reflective liquid crystal display device using polymer dispersed liquid crystal according to the related art.

6 is a schematic cross-sectional view taken along the line AA of FIG. 5 for explaining the general structure of a reflective liquid crystal display device according to the prior art.

FIG. 7 is a developed perspective view illustrating a detailed structure of the reflective liquid crystal display element shown in FIGS. 5 and 6.

[Explanation of symbols]

 1 Upper Substrate 11 Upper Electrode 2 Lower Substrate 21 Lower Electrode 3 Liquid Crystal Layer 4 Window Frame Plate 41 Window Hole 5 Reflector 51 Fluorescent Color Printing Section 6 Composite Front Plate 7 Back Plate 8 Composite Window Frame Front Plate 9 Composite Back Plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Isoda 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd.

Claims (4)

[Claims] 1. A polymer dispersed liquid crystal display device comprising a polymer liquid crystal layer interposed between an upper substrate having an upper electrode formed thereon and a lower substrate having a lower electrode formed on the outer surface of the upper substrate. A window frame plate having a window hole corresponding to a predetermined display pattern, and a composite front plate having an ultraviolet blocking action and an antiglare action were laminated in this order, and on the outer surface side of the lower substrate, corresponding to the display pattern. A polymer-dispersed liquid crystal display device, characterized in that a reflector having a fluorescent color printed portion and a back plate are laminated in this order. 2. A polymer dispersed liquid crystal display device comprising a polymer liquid crystal layer interposed between an upper substrate on which an upper electrode is formed and a lower substrate on which a lower electrode is formed, wherein an outer surface side of the upper substrate comprises: A window frame plate having a window hole corresponding to a predetermined display pattern, and a composite front plate having an ultraviolet blocking action and an antiglare action were laminated in this order, and on the outer surface side of the lower substrate, corresponding to the display pattern. A polymer-dispersed liquid crystal display device, characterized in that a composite back plate having a function as a reflection plate having a fluorescent color printing portion is laminated. 3. A polymer dispersed liquid crystal display device comprising a polymer liquid crystal layer interposed between an upper substrate on which an upper electrode is formed and a lower substrate on which a lower electrode is formed, wherein an outer surface side of the upper substrate comprises: While laminating a composite window frame front plate having a window hole function corresponding to a predetermined display pattern, an ultraviolet ray cutting function and an antiglare function, a fluorescent color printing section corresponding to the display pattern is provided on the outer surface side of the lower substrate. A polymer-dispersed liquid crystal display device comprising a reflection plate and a back plate which are laminated in this order. 4. A polymer dispersed liquid crystal display device comprising a polymer liquid crystal layer interposed between an upper substrate on which an upper electrode is formed and a lower substrate on which a lower electrode is formed, wherein an outer surface side of the upper substrate comprises: While laminating a composite window frame front plate having a window hole function corresponding to a predetermined display pattern, an ultraviolet ray cutting function and an antiglare function, a fluorescent color printing section corresponding to the display pattern is provided on the outer surface side of the lower substrate. A polymer-dispersed liquid crystal display device, which is characterized in that a composite back plate having a function as a reflection plate is laminated.