JP2005321738A - Image display device with daylighting function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device with a daylighting function capable of irradiating image display media with day light for a long time. <P>SOLUTION: An image display panel 10 is provided with image display media 100A and solar cells 12. The solar cells 12 are used for charging a battery 14 and as an auxiliary power source. A daylighting device 20 is installed in front of the image display panel 10 and irradiates the solar cells 12 and the image display media 100A with the reflected light obtained by reflecting the light from the sun by a reflecting mirror 21. The reflecting mirror 21 is changed in the angles in a lateral direction and a vertical direction so as to tail the sun 2 according to the result of the detection of a sunshine sensor 29. As a result, the image display panel 10 is always irradiated with the reflected light of the reflecting mirror 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display device with a daylighting function capable of holding an image without a power source, and in particular, an image with a daylighting function capable of irradiating solar cells with external light of sunlight or artificial light for a long time. The present invention relates to a display device.

  As a conventional image display device, for example, a device that displays an image by moving colored particles by an electric field is known (for example, see Patent Document 1).

  The image display medium described in Patent Document 1 includes a translucent surface substrate in which column electrodes formed on a surface substrate member are protected by a dielectric film, and row electrodes formed on a back substrate member. The back substrate protected by the dielectric film, the substrates are opposed to each other at a minute interval, the partition member is partitioned in a direction parallel to the substrate, and a plurality of cells are formed, and the negative electrode enclosed in each cell And a group of positively charged white particles and a group of positively charged black particles.

  In this image display device, when a DC voltage (200 V) is applied between the row electrode and the column electrode, an electric field is formed in the pixel between the electrodes, and white particles and black particles are separated from the surface substrate or the back surface depending on the direction of the electric field. Due to the contrast between the white particles and the black particles that have moved to the substrate side and adhered to the inner surface of the surface substrate, black and white image display is performed through the surface substrate.

According to this configuration, since the display does not disappear unless the electric field is changed, the image can be held with no power supply after the image is written. Therefore, the image can be displayed with low power consumption.
Japanese Patent Laying-Open No. 2002-99002 ([0008], FIGS. 23 to 24)

  However, according to the conventional image display device, it is necessary to apply a DC voltage of about 200 V when writing an image, and therefore it must be connected to a commercial power source or a large-capacity power source. is there. Therefore, it is conceivable to use a battery as a power source so that the installation location is not selected. In this case, it is necessary to charge the battery in order to reduce the battery replacement as much as possible or make the replacement unnecessary. When a solar cell is used as the power source for charging and further as an auxiliary power source, it is easily affected by the weather and the installation location, it is difficult to secure a long sunshine time, and charging tends to be insufficient.

  Accordingly, an object of the present invention is to provide an image display device with a daylighting function capable of irradiating external light to a solar cell for a long time.

  In order to achieve the above-mentioned object, the present invention collects an image display medium capable of holding an image without a power source, a solar cell, and external light of sunlight or artificial light, and uses the collected light to the solar cell. A lighting unit that irradiates; a battery that is charged by the power generation output of the solar cell; and a display drive unit that is supplied with electric power from the solar cell or the battery and switches an image displayed on the image display medium. An image display device with a daylighting function is provided.

  According to the image display device of the present invention, since the external light is collected and applied to the solar cell, the external light can be applied to the solar cell for a long time.

[First Embodiment]
(Configuration of image display device)
FIG. 1 shows a configuration of an image display device with a daylighting function (hereinafter also simply referred to as “image display device”) according to a first embodiment of the present invention. The image display device 1 captures sunlight while tracking the sun 2 with an image display panel 10 having solar cells 12, and the image display medium 10 </ b> A that configures the solar cells 12 and the image display panel 10 with the collected light. And a daylighting device 20 as a daylighting unit for irradiating the light.

(Image display panel configuration)
The image display panel 10 is an image for displaying an image by moving a colored particle by an electric field while being attached to stand up on the main body 11, a solar cell 12 attached to the lower front surface of the main body 11, and the main body 11. The display medium 100 </ b> A and the first control unit 13 that charges the solar battery 12 while causing the image display medium 100 </ b> A to perform display based on the image data are provided.

  The main body 11 is installed, for example, outdoors on a rooftop, a roof, a plaza, or the like of a building or a store. Therefore, the main body 11 is configured to have weather resistance and water resistance so that it can be used outdoors, and the first control unit 13 is built therein.

  The first control unit 13 includes a battery 14 serving as a power source for the image display device 1, a battery charging circuit 15 that charges the battery 14 with the solar battery 12, and a control circuit 16 that performs control on the image display panel 10 side. The display driving unit 17 drives the image display medium 100A under the control of the control circuit 16, and the image storage unit 18 stores image data to be displayed on the image display medium 100A. The image data may be input to the image storage unit 18 from a recording medium such as a CD-ROM, or may be input to the image storage unit 18 via a network such as a LAN (Local Area Network).

  The solar cell 12 is configured to collect a plurality of modules and obtain a desired voltage. The solar battery 12 is mainly used for charging the battery 14, but can be used together with the battery 14 for power supply. In this case, the battery is connected to the battery via a backflow prevention diode, or connected to the control circuit 16 or the like via a constant voltage circuit.

  As the battery 14, a rechargeable secondary battery such as a lithium ion secondary battery or a lead storage battery can be used.

  The battery charging circuit 15 has a circuit configuration for charging the battery 14 with electric energy generated by the solar cell 12 with a predetermined charging current, and preventing overcharge and overdischarge. Further, the solar cell 12 prevents backflow. In the case of not incorporating a diode for backflow, a backflow prevention diode is also provided.

  The control circuit 16 includes a CPU (Central Processing Unit), a semiconductor memory, and the like, and executes overall control of the image display panel 10. In addition, communication with the control circuit on the daylighting device 20 side is performed, and control for causing the image display panel 10 to perform an operation in cooperation is also executed.

  The display driving unit 17 generates an alternating voltage generating unit that generates an alternating voltage for initialization, and a DC voltage for applying an electric field to white particles and black particles enclosed in a plurality of cells of the image display medium 100A. And a DC voltage generator for generating.

  The alternating voltage generator is used to attach an initial state, for example, white particles to one substrate side and black particles to the other substrate side, and an alternating voltage having a predetermined frequency (for example, 200 Hz to 10 kHz). (For example, ± 70 V) is applied to all the pixels. The DC voltage generator is used when outputting a DC voltage (for example, +140 V or -140 V) and performing two-color display using white particles and black particles.

(Configuration of daylighting device)
The daylighting device 20 includes a semi-cylindrical reflecting mirror 21, a rotating shaft 22 that rotates the reflecting mirror 21, a wheel gear 23 attached to the rotating shaft 22, a worm gear 24 that meshes with the wheel gear 23, and the worm gear. A motor 25 that rotates the motor 24, a rack 26 that is vertically mounted on the back surface of the reflecting mirror 21, a pinion 27 that meshes with the rack 26, a motor 28 that has the pinion 27 mounted on the rotating shaft, and the reflecting mirror 21. A sunshine sensor 29 that is attached and detects the direction of the sun and a second control unit 30 for driving the motors 25 and 28 are provided. The rotating shaft 22, the wheel gear 23, the worm gear 24, the motors 25 and 28, the rack 26, and the pinion 27 form a drive mechanism.

  The reflecting mirror 21 is arranged so that sunlight is incident on an inner surface (reflecting surface) that has been mirror-finished so as to obtain a high reflectance, and the reflected light reaches the solar cell 12 of the image display panel 10. Is done. The reflecting mirror 21 is configured to be able to change the direction of the reflecting mirror 21 in a three-dimensional manner by rotating in the horizontal direction and the vertical direction, thereby tracking the sun. The reflecting mirror 21 may be a flat reflecting mirror (reflecting plate).

  As the sunshine sensor 29, for example, a combination of four photosensors, a pair of left and right, a pair of upper and lower, and a condenser lens can be used. By controlling the angle of the reflecting mirror 21 so that the incident light amounts are equal, the reflecting mirror 21 can continue to follow the sun 2.

  The second control unit 30 includes a control circuit 31 configured using a CPU and the like, and a drive circuit 32 that is driven by the control circuit 31 and drives the motors 25 and 28. The control circuit 31 operates the drive circuit 32 based on the amount of light output from the sunshine sensor 29, and the drive circuit 32 rotates the motors 25 and 28 so that the reflecting mirror 21 follows the sun 2. Even if the sunshine sensor 29 is not used, the control circuit 31 may cause the reflecting mirror 21 to follow the sun by controlling the drive circuit 32 based on the operation program.

(Overall configuration of image display medium)
FIG. 2 shows the configuration of the image display medium 100A. The image display medium 100A includes a surface substrate 111 having translucency, a back substrate 112 disposed to face the surface substrate 111, a plurality of partition members 113 connecting the surface substrate 111 and the back substrate 112, and the partition members. A plurality of cells 115 (115 </ b> A to 115 </ b> D) partitioned by 113, and a particle group including white particles 114 </ b> A and black particles 114 </ b> B having different charging characteristics. Although only four cells 115A to 115D are shown in the figure, in actuality, a larger number are arranged in a two-dimensional array according to the number of pixels.

(Configuration of each part of the image display medium)
The surface substrate 111 of the image display medium 100A has transparency as a whole. For example, the surface substrate member 111A made of a transparent glass substrate having a thickness of 1.1 mm and the like are provided inside the surface substrate member 111A. A plurality of transparent strip electrodes 116 (116A to 116D) made of indium tin oxide (ITO) or the like, and polycarbonate that protects these column electrodes 116 and stabilizes the charging characteristics of the white particles 114A and the black particles 114B A dielectric layer 111B made of the like and a protective layer 111C formed on the outer surface of the front substrate member 111A are laminated. In practice, the plurality of row electrodes 112B are arranged at predetermined intervals in a direction corresponding to the number of cells in a direction perpendicular to the paper surface. In addition, although it is desirable for transparency to be as high as possible in this invention, it may be translucent or colored and transparent.

  For the dielectric layer 111B, polycarbonate, polyester, polyimide, epoxy, or the like can be used depending on the charging characteristics of the white particles 114A and the black particles 114B enclosed in the cell 115. In addition, the dielectric layer 111B can contain a charge transport material in its insulating material. Inclusion of the charge transport material improves the chargeability of the particles by injecting the charge into the white particles 114A and the black particles 114B, and the charges of the particles 114A and 114B when the charge amount of these particles 114A and 114B becomes extremely large. Can be obtained, and the effect of stabilizing the charge amount of the particles 114A and 114B can be obtained.

  For the protective layer 111C, a polypropylene resin film or the like is used, and it is desirable to contain an ultraviolet absorber or the like in order to prevent the deterioration of the particles 114A and 114B.

  The back substrate 112 is formed of, for example, a back substrate member 112A made of an epoxy resin having a thickness of 0.6 mm, and a copper foil formed on one side of the back substrate member 112A and arranged in parallel at a predetermined interval in the direction perpendicular to the paper surface. A plurality of strip-shaped row electrodes 112B made of, etc., and a dielectric layer 112C that protects the plurality of row electrodes 112B and stabilizes the charging characteristics of the particles 114A and 114B.

  One row electrode 112B is provided in one cell 115, but a plurality of row electrodes 112B may be provided in order to increase the resolution. Similarly, a plurality of column electrodes 116 may be provided instead of one for each cell 115. The row electrode 112B and the column electrode 116 are arranged so as to intersect with each other, and a voltage is applied to the pixel between the column electrode 116 and the row electrode 112B by simple matrix driving.

  As a base material of the dielectric layer 112C, a dielectric material that is charged when a DC voltage is applied to the row electrode 112B is used as a material similarly to the dielectric layer 111B, and even after voltage application to the row electrode 112B is completed. The charging of the particles 114A and 114B attached to the back substrate 112 side is maintained.

  The dielectric layer 112C may be, for example, a colored layer formed by applying a coloring material to the back substrate member 112A or pasting a film-like material. In this case, three-color display is performed in combination with two colors of black and white particles. Can be. In order to display the color on the back substrate 112 on the screen, by applying an alternating voltage having a predetermined frequency between the electrodes 112B and 116 corresponding to the target pixel, particles existing in the target pixel are retreated to the periphery, and the colored layer The white particles 114 </ b> A and the black particles 114 </ b> B are not present on the upper surface, and the rear substrate color is made visible through the front substrate 112.

  The partition member 113 can be formed, for example, by screen-printing ink made of a thermosetting resin on the back substrate 112 and repeating a process of heating and baking in an oven a plurality of times until a desired height is reached. Alternatively, a photosensitive resin such as a dry resist film may be laminated and pasted on the back substrate 112 and exposed and developed into a predetermined pattern by a photolithography method. The upper end surface of the partition member 113 formed on the back substrate 112 and the surface substrate 111 are joined by an adhesive. As the partition member 113, in addition to the thermosetting resin, an insulating material such as a thermoplastic resin, an electron beam curable resin, a photocurable resin, or rubber can be used. As an adhesive that joins the partition member 113 and the surface substrate 111, a thermoplastic adhesive, a thermally activated adhesive, a hot-pressure adhesive, an ultraviolet curable adhesive, or the like can be used.

  The white particles 114 </ b> A and the black particles 114 </ b> B are charged with different polarities due to frictional charging by mutual friction. Here, it is assumed that the white particles 114A are negatively charged and the black particles 114B are positively charged.

  The white particles 114A are, for example, spherical particles of titanium oxide-containing crosslinked polymethyl methacrylate having a volume average particle diameter of 20 μm (classified as “Techpolymer MBX-20-White” manufactured by Sekisui Plastics Co., Ltd.) in 100 parts by weight of isopropyl trimethyl. It can be obtained by externally adding 0.4 parts by weight of titania fine powder treated with methoxysilane.

  The black particles 114B may be, for example, spherical fine particles of carbon-containing crosslinked polymethyl methacrylate having a volume average particle diameter of 20 μm (classified as “Techpolymer MBX-20-Black” manufactured by Sekisui Plastics Co., Ltd.). .

(Operation of image display device)
Next, the operation of the first embodiment will be described with reference to FIG. 1 and FIG. When the solar cell 12 is irradiated with artificial light such as sunlight or an illuminating lamp, the solar cell 12 generates power, and the electric energy generated by the power generation is used for charging the battery 14 via the battery charging circuit 15. Further, when it is not necessary to charge the battery 14 or the power generation output is not so much charged, the power generation output of the solar cell 12 is used as a power source for the control circuits 16, 31 and the like.

  When the two-color display is performed by the white particles 114A and the black particles 114B, the control circuit 16 operates the display driving unit 17, supplies power from the battery 14 to the display driving unit 17, and stores the image data stored in the image storage unit 18. Based on the above, the DC voltage generator of the display driver 17 is operated. The DC voltage generator sequentially applies a selection voltage (for example, 0V) to the row electrode 112B, and applies a positive or negative image voltage (for example, + 140V or -140V) to the column electrodes 116A to 116D according to the image data. Application is performed for a predetermined time (for example, 30 ms).

  The arrangement state of the particles 114A and 114B in FIG. 2 is the case where negative, negative, positive, and negative DC voltages are sequentially applied to the column electrodes 116A to 116D in synchronization with the application of the selection voltage to the row electrode 112B. The negatively charged white particles 114A move to the side of the column electrode 116C to which positive is applied and adhere to the inner surface of the surface substrate 111, and the positively charged black particles 114B are on the opposite side of the row electrode 112B. It adheres to the inner surface of the back substrate 112. The positively charged black particles 114B move to the column electrodes 116A, 116B, and 116D to which negative voltage is applied and adhere to the inner surface of the surface substrate 111, and the negatively charged white particles 114A are reversed. It adheres to the inner surface of the back substrate 112 on the electrode 112B side. In this way, a black and white image is displayed through the front substrate 111.

  Even when the application of voltage to the column electrodes 116A to 116D and the row electrode 112B is stopped, the electrostatic adhesion force between the particles 114A and 114B and the dielectric layers 111B and 112C is maintained, so that the particles 114A and 114B The black and white images are displayed for a long time while being held attached to the inner surfaces of the front substrate 111 and the rear substrate 112.

  In the initial state, the control circuit 16 operates the alternating voltage generation unit of the display driving unit 17 to apply an alternating voltage (for example, ± 70 V) having a predetermined frequency (for example, 800 Hz) to the row electrode 112B, An alternating voltage having an opposite phase (for example, ± 70 V) is applied to each column electrode 116. As the last pulse, for example, by applying a positive DC voltage to the column electrode 116, the white particles 114A adhere to the entire inner surface of the front substrate 111, and the black particles 114B adhere to the entire inner surface of the rear substrate 112. Return to state. At this time, when the image display medium 100A is viewed from the direction A in FIG. 2, only a white screen by the white particles 114A is visible.

  In the lighting device 20, a change in the amount of solar radiation of the sun 2 is detected by the sunshine sensor 29, and the second control unit 30 changes the vertical and horizontal angles of the reflecting mirror 21 based on the detection result. For example, when the sun 2 moves to the sun 2 ′, a difference occurs in the detected light amount (horizontal direction detected light amount) of the pair of left and right sensors. In accordance with the difference in the detected light amount, the control circuit 31 rotates the reflecting mirror 21 in the direction of the sensor with the larger light amount. That is, the control circuit 31 rotates the motor 25 via the drive circuit 32 to rotate the rotating shaft 22 of the reflecting mirror 21 in the direction of the sun 2 '. In the course of this rotation, the control circuit 31 stops driving the motor 25 when the detected light amounts of the pair of left and right sensors of the sunshine sensor 29 become equal. At this time, the amount of incident light from the reflecting mirror 21 to the solar cell 12 (and also the image display medium 100A) is maximized. This control is executed every time the difference in the amount of light detected by the sunshine sensor 29 exceeds a certain level (above a threshold value).

  Further, when the height of the sun 2 changes, a difference occurs in the amount of light detected by the pair of upper and lower sensors of the sunshine sensor 29. Therefore, the control circuit 31 rotates the motor 28 via the drive circuit 32 so that the rack 26 rotates in the direction opposite to the direction of the sensor having the larger light amount, and the rack 26 is moved up and down by the rotation of the pinion 27. And the energization to the motor 28 is stopped at the timing when the detected light amounts of the pair of upper and lower sensors of the sunshine sensor 29 become equal. By this control, the amount of incident light from the reflecting mirror 21 to the solar cell 12 and further to the image display medium 100A is maximized.

  The daylighting device 20 needs to operate only in the weather or time zone in which the light from the sun 2 can be irradiated to the solar cell 12 of the image display panel 10. Therefore, when the detection value of the sunshine sensor 29 or the power generation output of the solar battery 12 is below a certain level, the lighting circuit 20 does not need to be operated, so the control circuit 31 stops other circuits and driving mechanisms in the lighting apparatus 20. Let

(Effects of the first embodiment)
According to the first embodiment, the following effects can be obtained.
(A) Since the reflecting mirror 21 tracks the sun 2 by the daylighting device 20, the reflected light from the reflecting mirror 21 can be effectively incident on the solar cell 12 of the image display panel 10, and the solar cell 12 Since a high level of power generation output can be maintained, insufficient charging of the battery 14 can be resolved.
(B) Since the power generation output of the solar cell 12 can be increased, the utilization degree as an auxiliary power source such as a control circuit can be improved in place of the battery 14.
(C) By adjusting the emission angle of the reflected light of the reflecting mirror 21, it is possible to irradiate not only the solar battery 12 but also the image display medium 100A with sunlight, so that it can also be used as illumination light for the image display medium 100A.

[Second Embodiment]
FIG. 3 shows an image display apparatus according to the second embodiment of the present invention. In the second embodiment, in the first embodiment, the image display medium 100A uses the image display medium 100B in which the solar cell is built in, so that the single solar cell 12 is not required, and the fixed reflector is used. It is characterized in that 41 is provided as a daylighting unit. Therefore, the lighting device 20 used in the first embodiment is not necessary in this embodiment. Note that the reflecting plate 41 may be a reflecting mirror.

  The reflecting plate 41 has an inner surface (reflecting surface) with a mirror finish, or is painted or plated in a color that provides high reflectivity. The reflection plate 41 is inclined so that sunlight (or artificial light) from the rear of the image display panel 10 can be reflected on the image display surface of the image display medium 100B, and is predetermined with respect to the image display medium 100B. Is attached to the upper part of the main body 11 like a ridge by a support member 42 so that a distance of.

  In addition, by providing the reflecting plate 41, it is conceivable that the light of the sun 2 is blocked by the reflecting plate 41 depending on the time and causes a shadow on the image display medium 100B. In order to prevent such a situation from occurring, the reflection plate 41 may be a half mirror so that light from the sun 2 can pass through. Or you may make it the structure which can change the angle of the reflecting plate 41 automatically.

  In addition, a transparent plate 43 made of a transparent glass plate or plastic plate is attached between the reflecting plate 41 and the upper portion of the main body 11, and the sunlight (or artificial light) to the reflecting plate 41 is prevented from being blocked. Even when a person stands in front of the image display medium 100B in the case of rain or the like, consideration is given to preventing rain.

  Although the illustration of the control unit included in the image display panel 10 is omitted, the configuration of the first control unit 13 described in the first embodiment can be used as it is. However, the solar battery of the image display medium 100 </ b> B is connected to the battery charging circuit 15 instead of the solar battery 12.

(Configuration of image display medium)
FIG. 4 shows the layer structure of the image display medium 100B. The image display medium 100B is obtained by providing a transparent solar cell 117 made of a zinc oxide semiconductor or the like on the surface substrate 111 in the image display medium 100A of FIG. The solar cell 117 is provided on the front substrate member 111A, and a protective layer 111C is provided on the solar cell 117. Other configurations are the same as those of the image display medium 100A of FIG.

(Operation of image display device)
Next, the operation of the second embodiment will be described with reference to FIGS. When the power switch is turned on, power supply to each circuit in the image display panel 10 is started. Since the control for displaying an image on the image display medium 100B is the same as that in the first embodiment, description thereof is omitted. When the installation atmosphere of the image display panel 10 is bright, when the solar cell 117 is irradiated with sunlight or artificial light, the solar cell 117 generates power, and the generated output charges the battery 14 built in the main body.

  When the sun 2 is in front of the image display panel 10, the light of the sun 2 directly irradiates the image display medium 100B. When time elapses and the sun 2 moves to the position of the sun 2 ′ and is positioned behind the image display panel 10, sunlight is not directly applied to the image display medium 100 </ b> B. However, since the reflecting plate 41 is provided, the light of the sun 2 'enters the reflecting plate 41 through the transparent plate 43, and the reflected light is applied to the solar cell 117 in the image display medium 100B. Therefore, the solar cell 117 is irradiated with sunlight for a long time, the power generation time of the solar cell 117 can be lengthened, and the image display medium 100B is also illuminated.

(Effect of the second embodiment)
According to the second embodiment, the solar cell 117 of the image display medium 100B can be irradiated with sunlight from the rear of the image display panel 10 with a simple configuration in which only the reflector 41 is provided. 12 can effectively make sunlight enter, so that the solar cell 117 can maintain a high level of power generation output, and the lack of charging of the battery 14 can be resolved. Moreover, the utilization as an auxiliary power supply can be improved. Furthermore, since the reflected light of the reflecting plate 41 is irradiated to the image display medium 100B, it can also be used as illumination light for the image display medium 100B.

[Third Embodiment]
FIG. 5 shows an image display apparatus according to the third embodiment of the present invention. In the third embodiment, in the second embodiment, the reflecting plate 41 is installed to be inclined to the base portion 11A of the main body 11, and a reflecting surface is formed on the surface of the base portion 11A. Others are configured in the same manner as in the second embodiment.

  The main body 11 includes a base portion 11A, a pair of stands 11B erected on the base portion 11A, and a holder 11C attached to the upper end of the stand 11B. The holder 11C holds the image display medium 100B vertically. In addition, the stand 11B can also use a transparent plate other than a columnar body. On the surface of the base portion 11A, a reflective surface is formed by mirror finishing, painting of a color (white, silver, etc.) that can obtain a high reflectance, plating, or the like. The control unit is the same as that used in the second embodiment, and this control unit is built in the base unit 11A or the holder 11C.

(Operation of the third embodiment)
Next, the operation of the third embodiment will be described with reference to FIG. When the power switch is turned on, power supply to each circuit in the image display panel 10 is started. Since the control for displaying an image on the image display medium 100B is the same as that in the first embodiment, description thereof is omitted.

  When the sun 2 is in front of the image display panel 10, the light of the sun 2 directly enters the image display medium 100B, and the light reflected by the surface of the base portion 11A enters the image display medium 100B. Therefore, since the reflected light from the base portion 11A enters the image display medium 100B in addition to the ambient light, the irradiation light to the image display medium 100B increases as compared with the case where the base portion 11A is not provided.

  When time elapses and the sun 2 moves to the position of the sun 2 ', the sun light is not irradiated to the image display medium 100B directly or via the base portion 11A. However, since the reflection plate 41 is provided, the light of the sun 2 ′ reaches the reflection plate 41 through the pair of stands 11B, and the sunlight reflected by the reflection plate 41 is the solar cell 117 in the image display medium 100B. Is irradiated.

(Effect of the third embodiment)
According to the third embodiment, similarly to the second embodiment, even when the sun 2 is in front of the image display panel 10 or when the sun 2 'is in the rear, the image display medium 100B has the sun. Since light can be taken in, sunlight can be effectively incident on the solar cell 12.

[Fourth Embodiment]
FIG. 6 shows an image display apparatus according to the fourth embodiment of the present invention. In the fourth embodiment, in the first embodiment, the image display panel 10 is installed in a building 61A such as a building, and the daylighting device 20 is installed in a building 61B such as an adjacent or opposite building. 20 can be controlled from the image display panel 10 side. Then, wireless is used as a communication means for remotely controlling the lighting device 20 from the image display panel 10.

  The configuration of the image display panel 10 is the same as that of the first embodiment, but further includes a wireless unit 62A and an antenna 63A connected to the transmission circuit or transmission / reception circuit of the wireless unit 62A.

  The daylighting device 20 is the same as that of the first embodiment, but further includes a radio unit 62B including a receiving circuit or a transmission / reception circuit, an antenna 63B connected to the radio unit 62B, and a power source of the daylighting device 20 A battery 66, a battery charging circuit 67 for charging the battery 66, and a solar cell 68 as a charging source for the battery charging circuit 67. The solar cell 68 is installed in a sunny place. The drive mechanism 69 includes the rotary shaft 22, the wheel gear 23, the worm gear 24, the motors 25 and 28, the rack 26, and the pinion 27 described in the first embodiment.

  In addition, although the power supply of the lighting apparatus 20 was obtained from the battery 66, you may obtain from a commercial power source. In this case, instead of the battery 66 and the solar battery 68, a power supply circuit for obtaining a DC power supply from 100V or 200V is provided.

(Operation of the fourth embodiment)
Next, the operation of the fourth embodiment will be described with reference to FIG. When the power of the image display panel 10 is turned on, power supply from the battery 14 is started in the image display panel 10. When the first control unit 13 starts operation, an image is displayed on the image display medium 100A.

  On the other hand, in the daylighting device 20, cloudy weather, rainy weather, nighttime, or the like is determined by the second control unit 30 based on the output state of the solar cell 68, and the power supply by the battery 66 is turned on / off based on the determination result. It is determined. Alternatively, it is determined based on a command from the image display panel 10. Further, the battery 66 in the daylighting device 20 is charged by the battery charging circuit 67 using the power generation output of the solar cell 68.

  As described in the first embodiment, the daylighting device 20 drives the driving mechanism 69 by the second control unit 30 based on the detection result of the sunshine sensor 29, changes the angle of the reflecting mirror 21, and changes the image. The solar battery 12 of the display panel 10 is irradiated with the reflected light from the reflecting mirror 21.

  A command for stopping the operation of the image display panel 10 can be sent from the image display panel 10 to the daylighting device 20 in conjunction with the power-off of the image display panel 10. In this case, a signal is sent from the first control unit 13 to the daylighting apparatus 20 via the radio unit 62A and the antenna 63A. In the daylighting apparatus 20, the antenna 63B and the radio unit 62B receive radio waves from the image display panel 10. By this reception, the second control unit 30 stops the operation of the drive mechanism 69 or executes power-off of the daylighting device 20 or the like.

(Effect of the fourth embodiment)
According to the fourth embodiment, the same effect as that of the first embodiment can be obtained, and the distance between the display panel 10 and the daylighting device 20 can be freely set. It is possible to select a place where it is easily lit and install it. Alternatively, the lighting device 20 can be prevented from becoming an obstacle to the image display panel 10 with respect to the display of the image display panel 10.

[Fifth Embodiment]
FIG. 7 shows an image display apparatus according to the fifth embodiment of the present invention. In the fifth embodiment, in the first embodiment, the image display panel 10 includes a plurality of image display panels 10A, 10B, and 10C including the image display medium 100B shown in FIG. 4, and the plurality of image display panels 10A. , 10B, 10C, a plurality of reflecting mirrors 21A, 21B, 21C, a drive mechanism 69 (69A to 69C), and second control units 30A, 30B, 30C are provided. The two control units 30A, 30B, and 30C are controlled by the main control unit 70.

  The drive mechanism 69 includes the rotary shaft 22, the wheel gear 23, the worm gear 24, the motors 25 and 28, the rack 26, and the pinion 27 described in the first embodiment.

(Operation of the fifth embodiment)
Next, the operation of the fifth embodiment will be described with reference to FIG. For example, when the image display panel 10A located on the left side of FIG. 7 is shaded, the image display medium 100B is not irradiated with sunlight, so that no power generation output is generated in the solar cell 117 in the image display panel 10A.

  Therefore, under the control of the main control unit 70 so that the reflected light of not only the reflecting mirror 21A corresponding to the image display panel 10A but also the other reflecting mirrors 21B and 21C is intensively applied to the image display panel 10A. The second control units 30A to 30C are controlled. Each of the drive mechanisms 69 controls the angles of the reflecting mirrors 21A to 21C by the second control unit 30 so that the reflected light from the reflecting mirrors 21A to 21C is irradiated onto the image display panel 10A.

(Effect of 5th Embodiment)
According to the fifth embodiment, even when some image display panels 10 among the plurality of image display panels 10 are installed in the shade, they are concentrated on the solar cells 117 of the shaded image display panel 10. Since sunlight can be reflected on the battery, the battery can be charged in a short time.

  In the above embodiment, sunlight is reflected on the shaded image display panel 10A. However, the sunlight is reflected on one or a plurality of displayed image display panels among the plurality of image display panels. You may let them.

[Other embodiments]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. For example, the combination of the components between the embodiments can be arbitrarily performed. For example, the structure which used the solar cell 12 and the solar cell 117 together may be sufficient. Or you may add the reflecting plate 41 of 2nd Embodiment to 3rd Embodiment.

  Further, the arrangement and shape of the solar cell are not limited to the above embodiment, and various arrangements and shapes can be adopted. For example, a transparent solar cell is arranged on the image display surface side of both surfaces of the image display medium. Also good. Thereby, lighting efficiency can be made high.

  In addition, instead of the reflecting mirror or reflecting plate having the reflecting surface described above, the daylighting may be performed using a light guide such as an optical fiber or a prism, or a reflecting surface of another optical element, such as a prism and a reflecting mirror. As described above, a plurality of types of optical elements may be used in combination.

  In the above embodiment, the pair of electrodes (column electrode, row electrode) is provided on the pair of substrates (surface substrate, rear substrate). However, the pair of electrodes may be provided outside the image display medium. . This is a desirable mode of the present invention in that the transparency of the display screen is increased.

  In addition, as an image display medium, other liquid crystal having a memory property represented by ferroelectric liquid crystal, an electrophoretic method for switching display by moving charged particles, or particles for switching display by rotating charged particles. A rotation method or a magnetophoresis method in which particles are moved by magnetism to switch the display may be used.

  In the case where the solar cell is provided in parallel with the reflective image display medium, external light may be reflected not only on the solar cell but also on the image display medium. Thereby, the contrast of a display image becomes high.

  Further, a plurality of image display media arranged in a matrix or zigzag manner may be used, and a transparent solar cell may be provided on the image display surface side of each image display medium.

1 is a configuration diagram illustrating an image display device according to a first embodiment of the present invention. It is sectional drawing which shows the structure of the image display medium of FIG. It is a perspective view which shows the image display apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the structure of the image display medium of FIG. It is a perspective view which shows the image display apparatus which concerns on the 3rd Embodiment of this invention. It is a block diagram which shows the image display apparatus which concerns on the 4th Embodiment of this invention. It is a block diagram which shows the image display apparatus which concerns on the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image display apparatus 2, 2 'Sun 10, 10A-10C Image display panel 11 Main body 11A Base part 11B Stand 11C Holder 12 Solar cell 13 1st control part 14 Battery 15 Battery charging circuit 16 Control circuit 17 Display drive part 18 Image Storage unit 20 Daylighting device 21, 21A to 21C Reflector 22 Rotating shaft 23 Wheel gear 24 Worm gear 25 Motor 26 Rack 27 Pinion 28 Motor 29, 29A to 29C Sun sensor 30, 30A to 30C Second control unit 31 Control circuit 32 Drive circuit 41 Reflector 42 Support member 43 Transparent plates 61A, 61B Buildings 62A, 62B Radio units 63A, 63B Antenna 66 Battery 67 Battery charging circuit 68 Solar cells 69, 69A-69C Drive mechanism 70 Main control units 100A, 100B Image display medium 111 Surface Plate 111A surface substrate member 111B, 112C dielectric layer 111C protective layer 112 back substrate 112A the rear substrate member 112B row electrodes 112C dielectric layer 113 member 114A white particles 114B black particles 115A~115D cell 116,116A~116D column electrodes 117 solar cell

Claims (12)

An image display medium capable of holding an image without a power source;
Solar cells,
A daylighting unit for daylighting sunlight or artificial light, and irradiating the solar cell with the collected light;
A battery charged by the power generation output of the solar cell;
An image display device with a daylighting function, comprising: a display drive unit that is supplied with electric power from the solar cell or the battery and switches an image to be displayed on the image display medium.   2. The image display device with a daylighting function according to claim 1, wherein the daylighting unit includes a reflecting surface that reflects the external light to the solar cell. The image display medium has an image display surface on one surface,
The image display device with a lighting function according to claim 2, wherein the reflection surface reflects the external light irradiated from a side opposite to the image display surface of the image display medium to the solar cell. The image display medium has an image display surface on one surface,
The image display device with a daylighting function according to claim 1, wherein the solar cell is a transparent solar cell provided on the image display surface of the image display medium. The image display medium has image display surfaces on both sides,
The image display device with a daylighting function according to claim 1, wherein the solar cell is a transparent solar cell provided on each of the image display surfaces of the both surfaces of the image display medium. The solar cell is provided in parallel with the image display medium,
2. The image display device with a daylighting function according to claim 1, wherein the daylighting unit includes a reflection surface that reflects the external light to the solar cell and the image display medium. The solar cell is a plurality of solar cells,
The daylighting unit includes a plurality of reflecting surfaces for reflecting the external light to the plurality of solar cells, a plurality of changing mechanisms for changing the directions of the plurality of reflecting surfaces, and the external light to the plurality of solar cells. The image display device with a lighting function according to claim 1, further comprising: an orientation control unit that controls the plurality of changing mechanisms according to an irradiation state to individually control the orientations of the plurality of reflecting surfaces.   8. The image display device with a daylighting function according to claim 7, wherein the solar cells are a plurality of transparent solar cells respectively provided on image display surfaces of the plurality of image display media.   The daylighting unit includes a reflecting surface that reflects the external light to the solar cell, a changing mechanism that changes the direction of the reflecting surface, and a control unit that controls the changing mechanism to change the direction of the reflecting surface. The image display device with a daylighting function according to claim 1, further comprising:   The daylighting function according to claim 9, wherein the control unit controls the changing mechanism so that the reflected light reflected by the reflection surface by the sunlight tracks the sun and is applied to the solar cell. Attached image display device.   The image display device with a lighting function according to claim 9, wherein the control unit controls the change mechanism by radio. The image display medium includes a pair of substrates, at least one of which is transparent, and a positive or negative electrode disposed between the pair of substrates and moving between the pair of substrates in accordance with an electric field formed by an applied voltage. The image display device with a daylighting function according to claim 1, further comprising a charged particle group.