JP2000147465A - Information display device and information display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an information display device which allows periodic rewriting or rewriting of information according to a condition, insures high safety, is wide in a visual field angle, eliminates display unevenness in spite of a large screen and necessitates lesser electric power consumption and for which liquid crystals are used and an information display system. SOLUTION: This device displays the information by impressing pulse voltage to the scanning electrodes and signal electrodes arranged in a matrix form on a liquid crystal display element 10 formed by holding the liquid crystals exhibiting a cholesteric phase between transparent substrates, thereby selecting the liquid crystals existing in intersected positions to a planar state or focal conic state. The information (image data) is stored in a memory 26 and is rewritten at the prescribed timing by a clocking timer built in a signal controller 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information display device and an information display system that are installed indoors, outdoors, in a car, and the like using a reflective liquid crystal display element having a memory function.

[0002]

BACKGROUND OF THE INVENTION In recent years, the number of people using transportation such as buses, trains, airplanes and ships has increased. The business of providing advertisements to these users during boarding and boarding is also prosperous, and further improvement in advertising services is expected at present.

[0003] Generally, in transportation, advertisements of printed matter are posted on vehicles, onboard and on ships, so when updating information, for example, in the case of a train, a worker can copy old and new publications on the train. I was on the work table while running and was replacing it. However, in this case, the working efficiency is poor and the safety of workers is not good.

In view of this situation, if the present inventors devise a technology for updating and writing digital information on an electronic bulletin board by using communication means or the like, the demand described above will further increase, and the efficiency and the security will be improved. Therefore, the present invention was thought to be able to be improved.

[0005] In addition, conventionally, when it is necessary to urgently transmit information to passengers due to some accident,
An emergency was reported on board and on board. Therefore, there has been a problem that the sound of the broadcast is difficult to hear. On the other hand, the present inventors thought that these inconveniences could be solved if information could be provided to passengers visually.

[0006]

Heretofore, a display device using a liquid crystal display element has used a low-molecular liquid crystal. For this reason, the type using a glass substrate has a problem that, when the substrate is large, it is difficult to uniformly apply a rubbing orientation treatment and the substrate is easily broken. Further, the viewing angle of the display unit is narrow, and it is difficult to read the displayed information, and it is insufficient as a medium for transmitting information to a large number of passengers. In addition, since glass is used as the substrate, safety is inevitably lacking. Furthermore, when a shock or pressure is applied to the display panel itself, the orientation is disturbed, and image information cannot be read.In addition, the liquid crystal itself has no memory property, and it is necessary to constantly supply a constant power during display, and power consumption is reduced. Was also large.

[0007] In view of the above problems, an object of the present invention is to enable information to be rewritten periodically or immediately in response to circumstances, without the necessity of using a glass substrate, ensuring high security, and providing a wide viewing angle. It is an object of the present invention to provide an information display device and an information display system that have a uniform display even on a large screen and consume less power.

[0008]

In order to achieve the above objects, an information display device according to the present invention stores a reflective liquid crystal display element having a memory function and data of information to be displayed on the display element. Memory means, and time-measuring means for measuring rewriting timing of information to be displayed on the display element,
A power supply unit for the memory means and the timing means.

According to the present invention, there is provided a time measuring means, by which the information data stored in the memory means can be displayed on the display element at a predetermined time. You don't have to. Therefore, it is very useful as a means of advertising and posting in and out of vehicles and indoors. If information data corresponding to an emergency is stored in the memory means, information corresponding to the occurrence of the emergency can be displayed. further,
If a data receiving means for receiving information data transferred from the outside and storing it in the memory means is provided, arbitrary information can be input and displayed from the outside.

In the present invention, a reflective liquid crystal display element having a memory effect is used. As the liquid crystal, it is preferable to use a liquid crystal exhibiting a cholesteric phase at normal temperature (for example, a chiral nematic liquid crystal). This type of liquid crystal having memory properties does not require the use of glass for the substrate, and thus has no risk of breakage. In addition, orientation control is easy, the viewing angle is wide, and no unevenness occurs even on a large screen. Therefore, information can be effectively transmitted to many people. In addition, since it has a memory property, it is economical because power is not consumed for maintaining the display, there is no adverse effect of noise, and the display can be maintained even when the power is cut off.

Further, the present invention can be configured as an information display system. This system stores information data input from the outside in addition to the reflection type liquid crystal display element, the memory means, the timekeeping means, the power supply section and the data receiving means, and transfers the stored information data to the data receiving means. It has an external host device. According to this information display system, by transferring new information data from the external host device, the versatility and responsiveness of the display information is greatly improved.

The scope of application of the present invention is wide as shown below. If traffic information is displayed on the display element, a traffic sign that can be variably displayed instead of the conventional fixed display can be used as a sign corresponding to time zone, weather, and traffic information. If an advertisement, a message, a weather forecast, a map, or the like is displayed on the display element, it can be used for a message board at a station, a weather forecast board or site information board in a public place, a sketch drawing in a building, etc. Large display effect. Also, it can be used as an advertising board, a guide board, etc. in a train or a bus.

If a film-like speaker is incorporated, it can be used as an information display board with sound and does not require a space for installing a box-shaped speaker. If a plurality of display elements are independently juxtaposed, display information can be emphasized by moving a predetermined information screen between the respective display elements, and the advertising effect is improved. If the display element is multi-windowed, display information can be similarly enhanced.

If the display element is made of a material having a light-transmitting property during non-display time, the display element itself can be integrated with a window of a public vehicle such as a train or a bus or attached to a window glass for use. . Normally, the window functions as a non-display state (transparent state), and can function as an advertising board, a guidance display board, or the like when necessary.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an information display device and an information display system according to the present invention will be described below with reference to the accompanying drawings.

(Display Element Using Liquid Crystal Showing Cholesteric Phase) In a liquid crystal display element in which cholesteric liquid crystal or chiral nematic liquid crystal is sandwiched between two substrates, display is performed by switching the state of the liquid crystal between a planar state and a focal conic state. Do. When the liquid crystal is in the planar state, the helical pitch of the cholesteric liquid crystal is P, and the average refractive index of the liquid crystal is n.
Then, light having a wavelength λ = P · n is selectively reflected.
In the focal conic state, when the selective reflection wavelength of the cholesteric liquid crystal is in the infrared light range, it is scattered, and when it is shorter than that, it transmits visible light. Therefore, by setting the selective reflection wavelength in the visible light range and providing the light absorbing layer on the side opposite to the observation side of the element, it is possible to display the selective reflection color in the planar state and display black in the focal conic state. In addition, by setting the selective reflection wavelength in the infrared light range and providing a light absorption layer on the side opposite to the observation side of the element, light in the infrared light range is reflected in the planar state, but the wavelength in the visible light range is reflected. Is transmitted, so that a black display and a white display due to scattering in the focal conic state are possible.

By the way, assuming that a first threshold voltage for untwisting a liquid crystal exhibiting a cholesteric phase is Vth1,
After the voltage Vth1 has been applied for a sufficient time, the voltage becomes lower than a second threshold voltage Vth2 which is lower than the first threshold voltage Vth1, and a planar state is established. Further, when a voltage of Vth2 or more and Vth1 or less is applied for a sufficient time, a focal conic state is established. These two states are stable even after the voltage application is stopped. It is also known that a mixture of these two states exists, and it is known that gray scale display is possible (see US Pat. No. 5,384,067).

Since the liquid crystal exhibiting the cholesteric phase has a memory characteristic capable of maintaining a display state even when no voltage is applied, a display element partitioned into a plurality of pixels is driven by a simple matrix drive to obtain a desired image or character. Can be displayed. However, since this type of liquid crystal has a hysteresis characteristic, the display state is different even with the same driving voltage due to the state before the liquid crystal.

In view of the above, according to the present invention, the liquid crystal constituting all the pixels is simultaneously reset to a focal conic state which requires a long time for selection, and then the liquid crystal constituting each pixel is reset. Are sequentially applied to select the display state of the liquid crystal constituting all the pixels. According to this driving method, all the pixels are simultaneously reset to the focal conic state, so that the long selection time required to select the focal conic state is required only once for one screen. As a result, the rewriting speed is improved when simple matrix driving is performed.

In the liquid crystal display element used in the present invention, the liquid crystal material is sandwiched in the order of resin film / transparent electrode / alignment control film / liquid crystal material / alignment control film / transparent electrode / resin film as described in detail below. The alignment is determined by the combination of the alignment control film and the liquid crystal material. Usually, the alignment process is the same for the upper and lower layers, but this combination may be changed depending on the colorization, driving method, application, and the like.

Although such a name is used for the orientation control film for convenience, its function is not always clear. Rather than the general effect of controlling the alignment of liquid crystal molecules,
It can be said that the effect of improving the stability is great.

(Structure of Liquid Crystal Display Element) FIG. 1 shows an example of a reflection type liquid crystal display element used in the present invention. In the liquid crystal display element 10, a red display layer 11R for performing display by switching between red selective reflection and a transparent state is disposed on a light absorber 19, and display is performed thereon by switching between green selective reflection and a transparent state. A green display layer 11G to be performed is stacked, and a blue display layer 11B for performing display by switching between blue selective reflection and a transparent state is further stacked thereon.

Each of the display layers 11R, 11G, and 11B has a resin-made columnar structure 15 and a liquid crystal 16 sandwiched between transparent substrates 12 on which transparent electrodes 13 and 14 are formed, respectively. Further, an orientation control film or an insulating film (not shown) may be provided on the transparent electrodes 13 and 14.

The transparent electrodes 13 and 14 are respectively connected to the driving circuit 2
0, and the transparent electrode 1
A predetermined pulse voltage is applied between 3 and 14, respectively. In response to the applied voltage, the display is switched between a transparent state in which the liquid crystal 16 transmits visible light and a selective reflection state in which visible light is selectively reflected.

The transparent electrodes 13 and 14 provided on each of the color display layers 11R, 11G and 11B are composed of a plurality of strip electrodes arranged in parallel at a fine interval, respectively. They are opposed so as to be at right angles. Current is sequentially applied to these upper and lower strip electrodes. That is, display is performed by sequentially applying a voltage to each liquid crystal 16 in a matrix. This is called matrix driving. The liquid crystal display element 1 is formed by sequentially or simultaneously performing such matrix driving for each color display layer.
A full color image is displayed at 0.

By providing the light absorber 19 in the lowermost layer with respect to the viewing direction (the direction of arrow A), each color display layer 1
Light transmitted through 1R, 11G, and 11B is all light absorber 19
Is absorbed by That is, if all the color display layers are in a transparent state, black display is performed. As such a light absorber 19, for example, a black film can be used. Alternatively, a black paint such as black ink may be applied to the lowermost surface of the display element to form the light absorber 19.

In FIG. 1, the red display layer 11R shows a planar state, the green display layer 11G shows a focal conic state, and the blue display layer 11B shows a state where both the planar state and the focal conic state coexist.

(Various Materials of Display Element) As the transparent substrate 12, a colorless and transparent glass plate or a transparent resin film can be used. Examples of the material of the transparent resin film include polyarylate resin, polyether sulfone resin, polycarbonate resin, norbornene resin, amorphous polyolefin resin, and modified acrylate resin. The characteristics of resin film are high translucency, no optical anisotropy, dimensional stability, surface smoothness, friction resistance, bending resistance, high electrical insulation, chemical resistance, liquid crystal resistance, heat resistance , Moisture resistance, gas barrier properties, etc. are required.

As the transparent electrodes 13 and 14, transparent electrodes such as ITO and Nesa films can be used, and those formed on the transparent substrate 12 by sputtering or vacuum evaporation are used. Further, as the transparent electrode 14 in the lowermost layer, a black electrode can be used including the role as a light absorber.

As the liquid crystal 16, a liquid crystal exhibiting a cholesteric phase at room temperature is particularly preferable. Further, a chiral nematic liquid crystal obtained by adding a chiral dopant to a nematic liquid crystal can be used.

The nematic liquid crystal has rod-shaped liquid crystal polymers arranged in parallel, but does not have a layered structure. As the nematic liquid crystal, various single liquid crystals such as a biphenyl compound, a tolan compound, a pyrimidine compound, and a cyclohexane compound, or a mixed liquid crystal thereof can be used.
Those having a positive dielectric anisotropy are preferred. Specifically, a liquid crystal K15 mainly containing a cyanobiphenyl compound is used.
, M15, mixed liquid crystal MN1000XX (all manufactured by Chisso), E44, ZLI-1565, TL-213, B
L-035 (all manufactured by Merck).

The chiral dopant is an additive having a function of twisting the molecules of the nematic liquid crystal when added to the nematic liquid crystal. By adding a chiral dopant to a nematic liquid crystal, a helical structure of liquid crystal molecules having a predetermined twist interval is generated, thereby exhibiting a cholesteric phase.

The chiral nematic liquid crystal has the advantage that the pitch of the helical structure can be changed by changing the addition amount of the chiral dopant, whereby the selective reflection wavelength of the liquid crystal can be controlled. In addition,
In general, as a term representing the pitch of the helical structure of liquid crystal molecules, a “helical pitch” defined by a distance between molecules when the liquid crystal molecules rotate 360 degrees along the helical structure of the liquid crystal molecules is used.

As the chiral dopant, those having a layered helical structure in nematic liquid crystal molecules can be used. For example, it is a nematic liquid crystal such as a biphenyl compound, a terphenyl compound or an ester compound. Specifically, commercially available chiral dopants S811, CB1 obtained by bonding an optically active group as a terminal group of the compound.
5, S1011, CE2 (all manufactured by Merck) and the like can be used. A cholesteric liquid crystal having a cholesteric ring represented by cholesteric nonanoate (CN) can also be used as a chiral dopant.

As the chiral dopant to be added to the nematic liquid crystal, a plurality of types of chiral dopants may be mixed and used. In addition to the same type of optical rotation, a combination of different types of optical rotation may be used. The use of multiple types of chiral dopants can change the phase transition temperature of cholesteric liquid crystals, reduce the change in the selective reflection wavelength in response to temperature changes, and also provide dielectric anisotropy, refractive index anisotropy and viscosity. And other properties of the cholesteric liquid crystal can be changed, thereby improving the characteristics of the display device.

Materials used for the columnar structure 15 include:
For example, a thermoplastic resin can be used. For this purpose, a material which is softened by heating and solidified by cooling, is desired not to cause a chemical reaction with a liquid crystal material to be used and to have appropriate elasticity.

As specific examples, for example, polyvinyl chloride resin, polyvinylidene chloride resin, polymethacrylate resin, polyacrylate resin, polyvinyl acetate resin, polystyrene resin, polyamide resin, polyethylene resin, polypropylene resin, fluorine resin Resins, polyurethane resins, polyacrylonitrile resins, polyvinyl ether resins, polyvinyl ketone resins, polyvinyl pyrrolidone resins, polycarbonate resins, chlorinated polyether resins, and the like. These may be used alone or in combination, or the columnar structure 15 may be formed from a material containing at least one or a mixture of these.

The above substance is printed by a known printing method using a pattern so as to form dot columns. Depending on the size of the liquid crystal display element and the pixel resolution, the size of the cross-sectional shape, arrangement pitch, and shape (cylinder, drum, polygon, etc.)
Is appropriately selected. Further, it is more preferable to arrange the columnar structures 15 preferentially between the electrodes 13 because the aperture ratio is improved.

The shape may be a stripe shape instead of a dot shape, and may be selected according to the purpose. Further, in order to improve the accuracy of the gap control between the substrates 12, the columnar structures 15
When forming a spacer material having a size smaller than the thickness of the resin, for example, glass fibers, ball-shaped glass or ceramic powder, or spherical particles made of an organic material, the gap is changed by heating or pressing. If it is made difficult, gap accuracy is further improved, and voltage unevenness, color unevenness and the like can be reduced.

(Display of Color) In the color display layers 11R, 11G and 11B using such a chiral nematic liquid crystal, when the selective reflection wavelength of the cholesteric liquid crystal is in the visible light region, the helical axis of the cholesteric liquid crystal molecule is set on the substrate surface. In the focal conic arrangement state which is almost parallel to the visible light, the light is slightly scattered with respect to incident visible light, but is almost transparent. Also,
In a planar arrangement state in which the helical axis of the cholesteric liquid crystal molecules is substantially perpendicular to the substrate surface, light having a wavelength corresponding to the helical pitch is selectively reflected with respect to incident visible light. These two states can be switched by a change in a field such as a predetermined electric field, magnetic field, or temperature. Even when the field disappears, each state is maintained, that is, it has a memory property.

When a chiral nematic liquid crystal is used from the above characteristics, the amount of the chiral dopant to be added to the nematic liquid crystal is adjusted, and the helical pitch of the chiral nematic liquid crystal is adjusted so that the selective reflection wavelength is, for example,
By adjusting the wavelengths to correspond to the red, green, and blue light, respectively, it selectively reflects light in the wavelength ranges corresponding to red, green, and blue, respectively, in the planar arrangement state, In the state of alignment, a liquid crystal material which is transparent and transmits visible light can be obtained. By sandwiching the thus obtained liquid crystal material between the transparent electrodes, a color liquid crystal display element can be obtained.

(Addition of Dye for Improving Color Purity and Contrast, Arrangement of Color Filter)
In R, 11G, and 11B, in order to improve the color purity of the display performed by selective reflection and to absorb a light component that leads to a decrease in the transparency in the transparent state, a dye is added to each color display layer, or a dye equivalent thereto is added. A colored filter layer that provides an effect, that is, a plate member such as a color glass filter or a color film may be provided on each color display layer. The dye may be added to any of the liquid crystal material, the resin material, the transparent electrode material, and the transparent substrate material constituting each color display layer, and a plurality of the constituent elements may contain the dye. However, in order not to lower the display quality, the dye to be added and the filter layer to be added are:
It is desirable not to hinder color display by selective reflection of each color display layer.

As the dye to be added to the liquid crystal material, conventionally known various dyes can be used. For example,
Various dyes such as resin dyes and liquid crystal display dichroic dyes can be used. Specific examples of the dye for resin dyeing include SPR-Red1 and SPR-Yellow1.
(All manufactured by Mitsui Toatsu Dye Co., Ltd.). Further, specific examples of the dichroic dye for liquid crystal display include SI-426,
M-483 (all manufactured by Mitsui Toatsu Dye Co., Ltd.). Among these dyes, a dye that does not hinder display by the selective reflection wavelength of the liquid crystal and absorbs spectral light in a wavelength region that causes a reduction in display may be appropriately selected and used for each color display layer. Further, as described above, since the light component that degrades the display quality is considered to be mainly present on the short wavelength side, the dye that absorbs the spectrum light in the wavelength range shorter than the selective reflection wavelength of the liquid crystal. Is more preferably used.

The amount of the dye to be added is not particularly limited as long as the switching operation characteristics for displaying the liquid crystal are not remarkably reduced.
It is preferable to add the above, and about 1% by weight is sufficient.

When a color filter is employed in place of the addition of a dye, an additional filter layer material may be a colorless and transparent substance to which a dye is added. It may be a material that is inherently colored without adding a dye, or a thin film of a specific substance that functions similarly to the dye. Specific examples of the filter layer include commercially available colored glass filters and Wratten gelatin filter Nos. 8, no. 25 (all manufactured by Eastman Kodak Co.) can be used. Of course, instead of disposing the filter layer, the transparent substrate 12
It is clear that the same effect can be obtained even if the filter itself is replaced with the above-mentioned filter layer material.

(Color Display Method) In the liquid crystal display element 10 in which the respective color display layers 11R, 11G and 11B manufactured with the above-described material constitution are laminated, the blue display layer 11B and the green display layer 11G are formed by the liquid crystal 16 being focal. A red display can be performed by setting the transparent state in the conic arrangement and the selective reflection state in which the liquid crystal 16 has the planar arrangement in the red display layer 11R. Further, the blue display layer 11B is set in a transparent state in which the liquid crystal 16 is in a focal conic arrangement, and the green display layer 11G and the red display layer 11R are
Is set in the selective reflection state in which the elements are in a planar arrangement, so that yellow display can be performed. Similarly, red, green, blue, white, cyan, magenta, yellow, and black can be displayed by appropriately selecting the state of each color display layer between a transparent state and a selective reflection state. Further, by selecting an intermediate selective reflection state as the state of each color display layer 11R, 11G, 11B, display of an intermediate color becomes possible, and it can be used as a full-color display element.

Each color display layer 11 in the liquid crystal display element 10
The order of lamination of R, 11G, and 11B may be other than that shown in FIG. However, considering that the transmittance of the light in the long wavelength region is higher than that in the short wavelength region, the selective reflection wavelength of the liquid crystal contained in the upper layer is changed to that of the liquid crystal contained in the lower layer. It is better to keep it shorter than the wavelength
Since more light is transmitted to the lower layer, a bright display can be performed. Therefore, it is most desirable to sequentially form the blue display layer 11B, the green display layer 11G, and the red display layer 11R in order from the observation side (the direction of arrow A), and this state provides the most preferable display quality.

(Production Example of Liquid Crystal Display Element) The resin columnar structure 15 is formed on the upper substrate 12 by the printing method. FIG. 2 shows the upper substrate 12 in this state. here,
The resin film as the substrate is PES (polyether sulfone: manufactured by Tomo Bakelite Co., Ltd.) of 20 μm, and a screen printing coater MS400 (manufactured by Murakami Co., Ltd.) having a dot pattern of polyvinyl chloride with a thickness of about 15 μm is further formed thereon. And printed.

On this resin film, an ITO thin film was formed in a belt shape with a thickness of 700 Å by a known sputtering method. Subsequently, a silicon oxide film was laminated to a thickness of 4000 angstroms using the same device to form an insulating film. Next, the temperature of the resin film was adjusted to 25 ° C., and a sealing material 17 was printed around the thermoplastic polyester resin using the screen printing applicator MS400. After printing, the whole is 80 ° C on a hot plate,
Heating was performed for 20 minutes, and the solvent contained in the columnar structure 15 and the sealing material 17 was dried. As a result, a columnar structure 15 having a diameter of 35 μm, a height of 10 μm, and a pitch of 300 μm, and a sealing material 17 having a width of 1 mm and a height of 10 μm were formed.

Next, SE-610 was used as an orientation control material.
(Manufactured by Nissan Chemical Industries, Ltd.) by a known spin coating method to about 50
It was applied to a thickness of 0 Å and heated at 180 ° C. for 1 hour.

Next, another PES serving as a lower substrate
(Same as the upper side) is prepared, and the strip-shaped transparent electrode surface is superimposed on the upper side film, and the liquid crystal 16 is dropped between the two films 12 by the apparatus shown in FIG.
The liquid crystal 16 was sealed while heating and pressing with. However, at this stage, the sealing region at the end was opened without heating and pressing so that excess liquid crystal could be discharged to the outside.

Next, the two superposed films 12 were sandwiched between two stainless steel flat plates to obtain 0.37 kg / cm.
^With a load of ² applied, the film 12 was left in a thermostat at 160 ° C. for 1 hour, and the entire surface of the film 12 was bonded. Thereafter, the power of the thermostat was turned off, and the chamber was cooled to room temperature while applying a load.
Ultraviolet-curable resin Photolec A-704-60 (manufactured by Sekisui Fine Chemical Co., Ltd.) was applied to the peripheral portions of both films 12 and irradiated with ultraviolet light to complete the sealing.

As a liquid crystal material, MLC6068-00 is used.
No. 0 (a nematic liquid crystal material manufactured by Merck) and 2.4 wt% of a chiral material S-811 (manufactured by Merck) were added. Using the cholesteric liquid crystal display device thus manufactured, a full-color liquid crystal display device 10 was manufactured.

(Driving Circuit and Driving Method of Display Element) Since the pixel configuration in each display layer of the liquid crystal display element 10 is a simple matrix, as shown in FIG.
1, R2 to Rm and an m × n matrix of signal electrodes C1, C2 to Cn. A pixel at the intersection of the scanning electrode Ra and the signal electrode Cb (a and b are natural numbers satisfying a ≦ m and b ≦ n) is defined as LCa-b. Further, these electrode groups are respectively a scan drive IC 21 and a signal drive IC 22.
Of the driving ICs 21 and
From 22, a scanning voltage and a selection voltage are applied to each electrode.

The drive circuit of the liquid crystal display element 10 is not limited to the matrix-structured driver, but may be a signal drive IC for each line of the scan drive IC 21.
The image data may be transferred serially from 22 via a line latch memory. In this case, the scanning drive IC 21 is not line-compatible, but needs to be for serial use, and the cost of the driver is low.

In the liquid crystal display element 10, the display state of the liquid crystal is a function of the applied voltage and the pulse width. When a pulse voltage having a constant width is applied to the liquid crystal after resetting the liquid crystal to a focal conic state showing the lowest Y value (luminous reflectance) at first, the display state becomes as shown in FIG. Changes. In FIG. 5, the vertical axis represents the Y value, and the horizontal axis represents the applied voltage. When the pulse of the voltage Vp is applied, the planar state showing the highest Y value is selected, and the voltage Vf
Is applied, the focal conic state showing the lowest Y value is selected. When an intermediate voltage is applied, a state in which the planar state and the focal conic state exhibiting an intermediate Y value are mixed is selected, and halftone display becomes possible.

FIGS. 6A and 6B show waveforms (a) and (b) of pulse voltages applied to the liquid crystal of the test cell prototyped by the present inventors. Here, only the selection signal is applied from the signal electrode during scanning with respect to only one pixel. The voltage of the reset signal was 50 V, the pulse width (reset time) was 200 ms for the wavelength (a), and 50 ms for the wavelength (b).
Then, a selection signal for setting the liquid crystal to the planar state was applied at a voltage of 110 V for 5 ms. Here, 110V
However, the present invention is not limited to this value, and may take other values depending on the material and thickness of the liquid crystal and the pulse width of the voltage.

As shown in the waveform (a), when the reset signal is applied for 200 ms, the selection signal is applied regardless of whether the state of the liquid crystal before reset is the planar state or the focal conic state. A good planar state was obtained, and gradation expression when the voltage value of the selection signal was changed was also possible. On the other hand, as shown in the waveform (b), when the reset signal was applied for 50 ms, the liquid crystal was not always sufficiently reset, and the Y value when the liquid crystal was set to the planar state thereafter varied.

The above experiment has revealed that the longer the reset signal application time is, the less likely it is to be affected by the state before rewriting, and that if it is sufficiently long, it can be rewritten to a desired display state regardless of the state before rewriting. It is. In other words, by applying the reset signal for a sufficiently long time,
No longer affected by the previous state. In the waveform (a), it was found that the display time of about 4 gradations was possible when the reset signal application time was 200 ms. However, when the reset signal of 200 ms or more was applied, the selected display state depending on the difference in the initial state And the display of four or more gradations becomes possible.

(First Embodiment) FIG. 7 shows an information display device 1 according to a first embodiment of the present invention including a drive / image signal processing circuit 20 for rewriting image data. The liquid crystal display element 10 includes the scanning drive IC 21 and the signal drive IC.
The ICs 21 and 22 are driven by control signals from a scanning controller 23 and a signal controller 24 having a built-in timer. Image data to be newly displayed is input from the memory 26 to the signal controller 24, but before that, the image data conversion means 2
5 is converted into a selection signal.

The clock timer counts the timing of rewriting the image on the liquid crystal display element 10. The rewriting timing may correspond to a predetermined time interval or a predetermined time, and may be set according to the content of the displayed image (information). The memory 26 stores a plurality of image data, and sequentially outputs image data to be displayed at a timing based on the count of the clock timer. The memory 26 stores image data transferred from the CPU 33 described below.

(Second Embodiment) FIG. 8 shows an information display device 2 as a second embodiment including the liquid crystal display element 10 and a drive / image signal processing circuit 20. The information display device 2 receives information data transmitted from the outside by communication means (for example, telephone line, radio wave, cable) and receives the information data from the receiving circuit 31.
And input to the CPU 33 via the demodulation circuit 32.
Further, it is stored in the memory 35. Information is displayed on the liquid crystal display element 10 by reading data from the memory 35 and driving /
This is performed by driving the display element 10 by the image signal processing circuit 20. The power supply unit 36 supplies power to various circuits in the apparatus.

FIG. 9 shows a circuit configuration in which only a portion changed when information is rewritten can be partially rewritten.
Since the liquid crystal display element 10 has memory characteristics, partial rewriting is possible.

First, the current image data is stored in the image memory 1. The image data to be newly displayed is stored in the image memory 2. Line memory 1 has image memory 1
, Data per scanning electrode is read out and stored. In addition, data is similarly read from the image memory 2 and stored in the line memory 2. This line memory 1,
The data of No. 2 is compared by the comparing means, here the comparator 41, and the line numbers which do not match are stored in the address storage means. In this way, only the part that changes from the current image is extracted for each scanning electrode, and is set as a rewriting target.

A predetermined time is set in advance in a time counter built in the controller 24, and when this time has elapsed, the scanning controller 23 and the signal controller 24 refer to the address stored in the address storage means 42. Then, the control signal is output to the scanning signal driving IC 21 and the data signal driving IC 22 so that only the liquid crystal on the corresponding scanning electrode is rewritten. As a result, the scanning signal driving IC 21 and the data signal driving IC 22 drive only the liquid crystal to be rewritten. According to such a driving method, only the portion to be rewritten can be rewritten, and display can be performed faster than rewriting the entire screen. FIG. 10 shows a rewriting procedure when a plurality of different images are stored.

(Third Embodiment) FIG. 11 shows an information display system as a third embodiment. This system includes the information display device 2 shown in FIG. The external host device 50 includes an information input unit 51, a signal processing unit 52, a controller 53, and a driver 5.
4 and a power supply 55. The input unit 51 receives information data to be displayed by various methods from the outside. Driver 54 and receiving circuit 31 of information display device 2
(Refer to FIG. 8) is, for example, connected by a connector, and information data is transferred. In this case, the information display device 2 is installed at a predetermined place, and a maintenance person carries the external host device 50 and connects with the connector to transfer necessary information data.

(Fourth Embodiment) FIG. 12 shows an information display system as a fourth embodiment. External host device 5
Reference numeral 0 ′ includes an IRDA (infrared communication means) 56 at the output unit, and transfers information data to the information display device 2 by remote control. In this system, for example, if an external host device 50 'is installed in one room of a building, information of the information display devices 2 installed in a plurality of locations can be exchanged. Note that other communication means such as a frequency modulation communication means may be used instead of the IRDA 56.

(Fifth Embodiment) FIG. 13 shows an example in which the information display device 2 is mounted on a pole 61 in a train and used as an advertising board or a guide board. The display information may be exchanged using the external host device 50 or 50 ′, or may be exchanged by directly accessing the internal memory 35 (see FIG. 8).

When used as an in-vehicle guide board, for example, a route map of a route is displayed on a fixed screen, an instruction is given from the external host device 50 'to display the next stop station, or emergency guidance information is displayed. You can also transfer / display.

(Sixth Embodiment) FIG. 14 shows an example in which the information display device 2 shown in FIG. 13 is made easier for a passenger to see. In a vehicle, the sunshine condition (irradiation amount, irradiation angle, etc.) frequently changes, and the display device 2 may be difficult to see.
Therefore, the rotation motor 62 and the tilting rotation motor 63 are provided on the support portion of the display device 2, and the light receiving sensor 64 is provided near the display screen. The motor 62 rotates the display device 2 about a vertical axis 65 as a fulcrum, and the motor 63 rotates about the horizontal axis 66 as a fulcrum.

The light receiving sensor 64 detects the sunshine condition on the display screen. The control means (not shown) controls the motors 62 and 63 based on the detection result so that the display conditions are preferably programmed in advance, and adjusts the angle of the display device 2.

(Seventh Embodiment) FIG. 15 shows an example in which a liquid crystal display element 10 is provided on a window 67 of public transportation such as a train or a bus and used as an advertising board or a guide board. in this case,
The liquid crystal display element 10 is made of a material having a light-transmitting property at the time of non-display, and is attached to a window glass with a transparent adhesive,
If it is a double window glass, it is installed between the gaps. The control unit including the drive circuit 20 may be installed right above the window 67. The replacement of the information data is the same as in the fifth embodiment.

(Eighth Embodiment) FIG. 16 shows an example in which an information display device 2 and a controller 71 are provided on the inner wall of a vehicle. The controller 71 is embedded in the inner wall and can be opened only by a dedicated key, and includes an operation unit 72 as shown in FIG. The information to be displayed, the display order, the display time, and the like are input by the operation unit 72.

(Ninth Embodiment) FIG. 18 shows an example in which the information display device 2 shown in FIG. 16 is made easier for a passenger to see. In a vehicle, the illumination may be darkened, and at that time, the amount of reflected light of the liquid crystal display element 10 decreases. Therefore, a front light 73 for compensating the amount of reflected light is provided at a position where the display screen is irradiated. The light amount of the front light 73 is controlled based on the detection result of the light receiving sensor 74 provided near the display screen. If the detected light amount is equal to or less than the predetermined value, the light amount of the front light 73 is increased. If the detected light amount exceeds the predetermined value, the light amount of the front light 73 is fixed to a relatively low constant value or the light 73 is turned off.

(Tenth Embodiment) FIG. 19 shows an example in which the contrast of the information display device 2 shown in FIG. 16 due to a rise in temperature is corrected. In the liquid crystal used in the present embodiment, the contrast becomes too large as the temperature rises. Therefore, a temperature sensor 75 is provided near the liquid crystal display element 10,
When the temperature detected by the sensor 75 exceeds a predetermined value, the currently displayed screen is reset once, and the screen is rewritten with a voltage lower than the drive voltage at the time of writing. As a result, the contrast that has become too large due to the temperature rise can be recovered.

(Eleventh Embodiment) FIG. 20 shows an example in which a plurality of information display devices 2a to 2e are arranged in a vehicle. In this example, display in various modes is possible. For example, if one advertisement image is sequentially moved from the device 2a to the device 2e at a constant time interval, an advertisement effect having a higher impact than that displayed on one screen is exhibited. The devices 2a to 2e may be used at the same time to display warning information at the time of sudden stop (lighting in red, etc.) or to perform decorative display. This kind of display control can be performed by providing the drive control unit 81 separately, and
2e can be commonly controlled.

As a modification of this type of display mode,
A plurality of display elements 10 may be provided on one display panel in a multi-window manner. A display mode with various impacts can be adopted as a multi-window advertising board or guide board.

(Twelfth Embodiment) FIG. 21 shows an example in which guide information such as a destination of a train, a stop station, and an arrival time can be viewed by a passenger by a key touch operation. Here, the information display device 2 and the key operation panel 82 are provided on the inner wall of the vehicle.
And side by side. Items such as a destination and a stop station are assigned to each key of the panel 82. When a passenger operates a key of a desired item, a guidance screen of the corresponding item is displayed on the liquid crystal display element 1.
Appears on zero.

(Thirteenth Embodiment) FIG. 22 shows an example in which the present invention is used as a message board installed in a station waiting room, a parking area of a highway, or the like. In this information display device 2, the display surface of the liquid crystal display element 10 has an advertisement / guide area 10a and a message area 10b.
The above-described various advertisement displays and guide displays are performed in the advertisement / guide area 10a. Message area 1
0b is configured as a well-known liquid crystal display type touch panel, and an arbitrary message can be written using a light pen or the like. The written message is erased as a certain time elapses.

(Fourteenth Embodiment) FIG. 23 shows an example used as a guide board at a wedding hall. The display part and the background part of the “what” house can be replaced at a predetermined time or by remote control. The photo display area 10c may be a liquid crystal display, or a method in which a picture or the like is fitted in only the area 10c.

(Fifteenth Embodiment) FIG. 24 shows an example in which a bulletin board or a display board is used in a place where people gather, such as in a train, a waiting room at a station, a library or a hall. The display area 10d of the liquid crystal display element 10 is a news column for displaying character information, and the display content is frequently changed. In the background, the weather forecast is symbolized and displayed. Any information data can be input by remote control using the external host device 50 '.

In the information display device 2, a touch panel 83 is provided at the lower part of the display screen so that the area and time of the weather forecast to be displayed can be input.

(Sixteenth Embodiment) FIG. 25 shows an example of a method of displaying information on the liquid crystal display element 10. When displaying information "B" following information "A" currently displayed, FIG.
Instead of completely deleting "A" and then displaying "B", once "A" and "B" are once reduced from screen 1 displaying "A" as shown in screen 2. The screen is displayed in parallel, and thereafter, the screen is switched to a screen 3 displaying only “B”.
According to this display method, information is not interrupted and an impressive display effect is exhibited.

(Seventeenth Embodiment) FIG.
5 shows an information display device 2 provided with the information display device 5. The speaker 85 has a film shape and is juxtaposed with the liquid crystal display element 10. An operation unit 86 for adjusting volume and displaying information is provided below the speaker 85.
Are integrated with the power supply unit and the like. If the speaker 85 is transparent, the matching with the display element 10 is good.

(Other Embodiments) The information display device and the information display system according to the present invention are not limited to the above embodiments, but can be variously modified within the scope of the invention. In particular, specific examples and numerical values of various materials such as a liquid crystal are merely examples. In addition, there are various installation locations, usage methods, and display contents of the display device or the system, and an optimum control method may be adopted.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a liquid crystal display element used in an information display device or an information display system according to the present invention.

FIG. 2 is a plan view showing a state in which a columnar structure and a sealing material are formed on a film substrate of the liquid crystal display element.

FIG. 3 is an explanatory view showing a manufacturing process of the liquid crystal display element.

FIG. 4 is a block diagram showing a matrix drive circuit of the liquid crystal display element.

FIG. 5 is a graph showing a relationship between a voltage applied to a selection signal and a Y value in the matrix driving circuit.

FIG. 6 is a chart showing a voltage waveform experimentally applied to a test cell.

FIG. 7 is a block diagram showing a driving / image signal processing circuit used in the first embodiment.

FIG. 8 is a block diagram showing a control circuit used in the second embodiment.

FIG. 9 is a block diagram showing a driving circuit for partially rewriting information.

FIG. 10 is a chart showing a procedure for rewriting information.

FIG. 11 is a block diagram showing a third embodiment.

FIG. 12 is a block diagram showing a fourth embodiment.

FIG. 13 is an explanatory view showing a fifth embodiment.

FIG. 14 is an explanatory view showing a sixth embodiment.

FIG. 15 is an explanatory view showing a seventh embodiment.

FIG. 16 is an explanatory view showing an eighth embodiment.

FIG. 17 is a perspective view showing a controller used in the eighth embodiment.

FIG. 18 is an explanatory view showing a ninth embodiment.

FIG. 19 is an explanatory view showing a tenth embodiment.

FIG. 20 is an explanatory view showing an eleventh embodiment.

FIG. 21 is an explanatory view showing a twelfth embodiment.

FIG. 22 is an explanatory view showing a thirteenth embodiment.

FIG. 23 is an explanatory view showing a fourteenth embodiment.

FIG. 24 is an explanatory view showing a fifteenth embodiment.

FIG. 25 is an explanatory view showing a sixteenth embodiment.

FIG. 26 is an explanatory view showing a seventeenth embodiment.

[Explanation of symbols]

 1, 2 ... Information display device 10 ... Liquid crystal display device 20 ... Drive / image signal processing circuit 26 ... Memory 31 ... Receiving circuit 36 ... Power supply unit 50, 50 '... External host device 85 ... Film speaker

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/36 G09G 3/36 F term (Reference) 2H088 EA23 GA03 HA06 JA16 MA20 2H093 NC01 NC15 NC16 ND39 NF17 NG20 5C006 AA02 AA03 AA22 AC15 AF51 AF71 BA11 BB12 BB28 BF01 BF05 BF14 BF15 BF16 BF29 FA01 FA16 FA22 FA47 FA55 5C080 AA10 BB05 CC03 DD05 DD21 DD26 EE01 EE17 FF12 GG12 JJ02 JJ04 JJ06 KA20 AA49A24 GBA11A11

Claims (10)

[Claims] 1. A reflection type liquid crystal display element having a memory function, a memory means for storing data of information to be displayed on the display element, and a timing means for timing rewriting timing of information to be displayed on the display element. An information display device, comprising: a power supply unit for the memory unit and the timing unit. 2. The information display according to claim 1, further comprising a selection unit that selects information to be displayed on the display element from a plurality of pieces of information data stored in the memory unit in a predetermined order. apparatus. 3. An information display apparatus according to claim 1, further comprising a data receiving means for receiving information data transferred from outside and storing the data in said memory means. 4. An information display device according to claim 3, further comprising: an external host device for storing externally input information data and transferring the stored information data to said data receiving means. Information display system. 5. The information display device or information display system according to claim 1, wherein the information to be displayed on the display element is traffic information. 6. The information to be displayed on the display element is an advertisement,
The information display device or the information display system according to claim 1, wherein the information display device is at least one of a message, a weather forecast, and a map. 7. The information display device or information display system according to claim 1, further comprising a film speaker. 8. The information display device according to claim 1, further comprising a plurality of reflective liquid crystal display elements, wherein each of the display elements can be independently installed at a plurality of locations. Display system. 9. The information display according to claim 1, further comprising a plurality of reflective liquid crystal display elements, wherein each display element is provided in a single display panel in a multi-window manner. Device or information display system. 10. The information display device or information display system according to claim 1, wherein the display element is made of a material having a light-transmitting property when non-display is performed.