Composite display device

Abstract

To provide a composite display device which can be enlarged without complicating the device for color display while effectively presenting an energy saving property and brightness or sharpness of display at outdoor and bright places by a monochromatic display device.SOLUTION: An electrophoretic display device 12 is configured by arranging a plurality of display sections 14 in parallel in vertical and horizontal directions, the display section being capable of displaying an arbitrary white display location W and an arbitrary black display location B. A projector device 16 capable of projecting a color image is disposed while being opposed to the electrophoretic display device 12, and an arbitrary color image can be projected onto each of the display sections 14. The plurality of display sections 14 of the electrophoretic display device 12 and the projector device 16 are connected to a controller 18, and the controller 18 controls operations of the devices in a form such that the color image the projector device 16 can project corresponds to a monochromatic image that the electrophoretic display device 12 can display.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a composite display device that can be enlarged without complicating the device for color display, while taking advantage of the energy saving properties of a monochrome display device that can only display black and white, and the brightness and clarity of the display in bright outdoor locations, and is suitable for use as a large-screen display device both indoors and outdoors. [Background technology]

[0002] Conventionally, there are four main types of large-screen display devices known for displaying images, text, and the like at exhibitions or indoors and outdoors: LED display devices, liquid crystal display devices, projector-type display devices, and electrophoretic display devices.

[0003] An LED display device is a display device that forms a display screen by arranging and installing on a wall or the like any number of square or rectangular display units with sides of about 30 to 60 cm, each of which has three primary color LED light-emitting elements arranged at intervals of about 1 to 10 mm. A liquid crystal display device is a display device that forms a display screen by arranging and installing on a wall or the like any number of color liquid crystal display units, which are generally rectangular with sides of about 40 to 90 cm, similar to home televisions. A projector-type display device is a display device that forms a display screen by projecting a color image from a color projector such as an LCD type directly onto a wall or the like, or onto a screen installed on a wall.

[0004] On the other hand, an electrophoretic display device is a display device that uses the electrophoretic phenomenon and forms a display screen by arranging any number of square or rectangular reflective display units, each measuring about 20 to 90 cm on a wall or the like. The electrophoretic display method, which is the basic technology of this electrophoretic display device, is a representative display technology that embodies the concept of electronic paper, which can realize a display that does not consume power to maintain the display by driving fine particles encapsulated in microcapsules together with an insulating liquid with an electric field.

[0005] The following Patent Document 1 also discloses a technology in which a multicolor image light is projected from a projector device, which is a projector-type display device, onto a screen made of electrophoretic electronic paper having two types of particles, black and white. However, the same image as the image projected from the projector device is displayed on the screen.

[0006] Patent Document 2 also discloses a technique for projecting image light from a projector onto a screen composed of a particle sheet, electrodes, etc., but this screen does not have an image display function.

[0007] Patent Document 3 also discloses a technology in which an image is displayed on an electrophoretic display device and image light is projected from a projector device. However, the image light from this projector device is projected onto an ordinary screen, not onto an electrophoretic display device, and the image displayed on the electrophoretic display device is not directly observed by the naked eye, but is input into the projector device and projected onto the screen. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP2008-310260A [Patent Document 2] JP2018-32035A [Patent Document 3] JP 2005-283819 A Summary of the Invention [Problem to be solved by the invention]

[0009] Among the conventional technologies, LED displays and liquid crystal displays are luminous types and require a large amount of luminous energy to maintain display, typically 500 watts / m 2 Therefore, for example, a 4 m wide, 3 m high (12 m area) 2) requires a power consumption of 6000 watts to display the image on its screen, and the electricity bill is estimated to be about 1.3 million yen per year. The spread of display devices that require such a large amount of power consumption runs counter to the global trend of energy conservation and CO2 emission reduction aimed at preventing global warming, and the issue is that their operation imposes an extremely large economic burden on the installers of the display devices.

[0010] Furthermore, because these devices are luminous, when used outdoors, the brightness of the display is relatively insufficient compared to the outdoor light, particularly in direct sunlight, resulting in a blurred display. To prevent this, a larger amount of power must be input to provide a bright luminous display screen that can compete with the outdoor light, resulting in energy conservation and high operating costs.

[0011] The projector type display device is a projection type, and has a power output of 100 watts / m 2 Therefore, for example, a 4 m wide, 3 m high (12 m area) 2 ) requires a power consumption of 1200 watts to display the information on the screen, and the electricity bill is estimated to be about 260,000 yen per year. Therefore, it consumes less power than LED display devices and LCD display devices, but the display becomes unclear outdoors, so its practical use outdoors was limited to the nighttime after sunset.

[0012] Electrophoretic displays are reflective and do not require energy to emit light, so they consume little energy, typically less than 1 Watt / m 2 It has the advantage of consuming about the same amount of power as a reflective type screen, and because it is a reflective type screen, the screen will in principle become brighter and clearer outdoors, especially in direct sunlight (this is the same principle as how printed matter, which is also a reflective type screen, appears clearer in brighter places), but the display unit is basically black and white. For this reason, it is being sold commercially as a black and white e-book terminal and is becoming increasingly popular.

[0013] On the other hand, as a technology for colorizing electrophoretic displays, a structure is known in which tiny color filters of the three primary colors, with the size of a displayed pixel being the basic unit per color of the color filter, are arranged on the screen of the electrophoretic display. In principle, this structure has the problem that the brightness of the screen becomes about 1 / 3 of that of black and white display due to the color filters, resulting in a decrease in the amount of reflected light, making the color display screen dark and unclear. In addition, arranging tiny color filters on the surface of the display screen is a complicated process, which causes the problem of extremely high manufacturing costs for the display screen.

[0014] On the other hand, in Patent Document 1, although an electrophoretic method having two types of particles, black and white, is used, there is no control technology, and therefore it has a drawback that an image different from the content projected from the projector device cannot be displayed on the screen. In Patent Document 2, image light is projected from the projector device onto a screen similar to the electrophoretic method, but the screen does not have an image display function. Furthermore, in Patent Document 3, an image is displayed on an electrophoretic display device separately from projecting image light from the projector device, but the image displayed on the electrophoretic display device is not directly observed.

[0015] For the reasons described above, conventional LED display devices, liquid crystal display devices, projector-type display devices, and electrophoretic display devices, as well as the technologies disclosed in Patent Documents 1 to 3, have not been able to provide large-screen color images outdoors at low cost.

[0016] The present invention has been made in view of the above-mentioned background, and has as its object to provide a composite display device that can be made large-screen without complicating the device for color display, while taking advantage of the energy-saving properties of a monochrome display device that can only display black and white, and the brightness and clarity of the display in bright outdoor locations. [Means for solving the problem]

[0017] The invention described in claim 1 that solves the above problem is a monochrome display device in which a plurality of display units capable of displaying any black and white image using black and white particles are arranged side by side; a projector device capable of projecting a color image onto a display unit; a control device that controls operations of a plurality of display units of the monochrome display device and the projector device; A composite display device having: The display unit is controlled by a control device to display an arbitrary black-and-white image, and the projector device is controlled by the control device to project a color image that corresponds to the black-and-white image and is to be displayed onto the display unit, thereby forming a composite display device.

[0018] In the composite display device of the invention of claim 1, the monochrome display device has a plurality of display sections arranged side by side, each capable of displaying a desired black-and-white image using black and white particles, and the projector device projects a color image onto each of the display sections. Also, the control device controls the operation of the plurality of display sections and the projector device, so that the display sections display a desired black-and-white image while being controlled by the control device, and the projector device projects a color image that corresponds to the black-and-white image and is to be displayed onto the display sections while being controlled by the control device.

[0019] In this case, to apply this composite display device to a large display screen to be applied to a wall surface, etc., the first thing to consider is arranging any number of display units, called electronic tiles, which are the display units and are, for example, about 10 cm square, on the wall. Furthermore, this composite display device makes it possible to project colored light corresponding to a color image onto all or part of such a large display screen using a projector device.

[0020] Therefore, by illuminating colored light from a projector device onto the screen of each display section of a monochrome display device that only has black and white display capabilities, it is possible to achieve a color display effect similar to that achieved when a color filter is placed on each of these display sections.

[0021] Therefore, the composite display device according to the present invention solves the problems of the complexity of the manufacturing process and increased manufacturing costs involved in arranging color filters on the screen surface of a monochrome display device, and also solves the problem of reduced display brightness caused by the arrangement of color filters by increasing the amount of light provided by the projector device.

[0022] As described above, according to the present invention, it is possible to obtain a composite display device that can be made large-screen without complicating the device for color display, while taking advantage of the energy-saving properties of a monochrome display device that can only display black and white, and the clarity of the display in bright outdoor areas.

[0023] The invention of claim 2 is the composite display device of claim 1, in which the monochrome display device is a reflective electrophoretic display device that uses an electrophoretic medium. In other words, by using a reflective electrophoretic display device that uses a conventionally known electrophoretic medium as the monochrome display device, it becomes possible to fabricate a composite display device with a simple device configuration.

[0024] The invention of claim 3 is a composite display device as described in claim 1, in which a projector device projects a color pattern of three or more colors in a repeated arrangement onto each display unit in response to the pixel size and arrangement period of each display unit constituting a monochrome display device, thereby making it possible to display the color on the white-displayed parts of each display unit.

[0025] As a result, the color above the white display part of each display section becomes clearly visible, and color display is possible. This is a color expression method similar to that of a color liquid crystal display device, which realizes color expression by combining a liquid crystal display layer that is only responsible for changing the transmittance with a mosaic color filter (the liquid crystal layer changes only the amount of transmitted light for each pixel, and the color of the pixel is added by the color of the color filter in the liquid crystal layer).

[0026] The invention of claim 4 is a composite display device as described in claim 1, in which a projector device projects a color image to be displayed onto each display unit, and each display unit controlled by a control device displays a black-and-white image by extracting only the brightness components corresponding to the color image. Generally, a projector device projects an image onto a projection screen surface that is white or silver, etc. In this case, the display pixels that are closest to black that can be expressed are obtained by minimizing the amount of light irradiated onto the screen, ideally in an area where the amount of projected light is zero. However, when using a white screen, for example, the display pixels that appear white due to indoor illumination irradiating the white screen will express black display pixels.

[0027] That is, a fundamental problem with projector devices is that they are not good at expressing black areas, and particularly when the projection environment is bright, areas where black is desired to be expressed appear as light gray. However, in this claim, by projecting a color image to be expressed from the projector device onto a display unit and displaying a black-and-white image on this display unit that extracts only the brightness component of the color image, it becomes possible to obtain an image that expresses the light and dark of a color image, including black, with high contrast, even when using a projector device.

[0028] The invention of claim 5 is a composite display device as described in claim 1, which displays a black-and-white image, such as a line drawing in a coloring book, on the display section of a monochrome display device, and, under the control of a control device, irradiates colored light from a projector device in accordance with the black-and-white image, as if coloring in a coloring book. This makes it possible to clearly express color differences and contours in a color image that could not be adequately expressed by projecting a color image from a projector device alone, resulting in a clear image. In other words, this claim is suited to the purpose of vividly displaying color illustrations, color patterns, etc.

[0029] The invention of claim 6 is the composite display device of claim 1, in which an arbitrary black and white image is displayed on the display section of the monochrome display device, and a projector device projects a pattern in which various colors are arranged onto the display section. This makes it possible to add a color background to any black-and-white image displayed on the display section of a monochrome display device, thereby enhancing the vividness of the display.

[0030] The invention of claim 7 is a composite display device as described in claim 1 in which an identifiable display area that should be distinguished from other parts is placed only on a part of the display area of ​​a monochrome display device, and the identifiable display area can be emphasized by projecting a color image from a projector device onto the identifiable display area. That is, a specific color of light can be projected from the projector device onto a specific portion of the display section of a monochrome display device, making the display content of that portion stand out. For example, a digital numeric display or an analog needle-type clock display can be arranged on a specific portion of each display section, and the clock can be made to stand out and easy to read by projecting a color of light, such as a solid yellow color, onto that portion from the projector device.

[0031] The invention of claim 8 is a composite display device as described in claim 1, in which a light receiving sensor connected to a control device is placed either on the surface of a monochrome display device or in a projector device, and as this light receiving sensor receives light to be synchronized, the display unit displays a black and white image and the projector device projects a color image while being controlled by the control device. In other words, by the light receiving sensor receiving light with which synchronization should be performed, it becomes possible to easily synchronize the operations of the monochrome display device and the projector device. Effect of the Invention

[0032] With the composite display device of the present invention, it is possible to take advantage of the energy saving properties of a monochrome display device that can only display black and white, and the brightness and clarity of the display in bright outdoor locations, while making it possible to achieve a large screen without complicating the device for color display. [Brief description of the drawings]

[0033] [Figure 1] 1 is a schematic diagram of a composite display device according to one embodiment of the present invention; [Diagram 2] 1 is a conceptual diagram of an electrophoretic display device applied to one embodiment of the present invention. [Diagram 3] 1 is a conceptual diagram showing a display unit applied to one embodiment of the present invention and a state in which an electrophoretic display device is formed by using the display unit; [Figure 4] FIG. 1 is an explanatory diagram showing a first application example of a composite display device according to one embodiment of the present invention, in which (A) is a diagram showing the pixels of the display unit, (B) is a diagram showing the projection of a projector device, and (C) is a diagram showing a red figure being displayed. [Diagram 5] FIG. 11 is an explanatory diagram showing a second application example of a composite display device according to one embodiment of the present invention, in which (A) is a diagram showing an example of a display of an electrophoretic display device, and (B) is a diagram showing an example of a projected color pattern display. [Figure 6] FIG. 11 is an explanatory diagram showing a third application example of a composite display device according to one embodiment of the present invention, in which (A) is a diagram showing a black and white image, (B) is a diagram showing an example of a projected color pattern display, and (C) is a diagram showing color differences and contours of a color image. [Figure 7] FIG. 11 is an explanatory diagram showing a fourth application example of a composite display device according to one embodiment of the present invention, in which (A) is a diagram showing a black and white image, (B) is a diagram showing an example of a projected color pattern display, and (C) is a diagram showing an image in which colored light is combined with a black and white image. [Figure 8] FIG. 11 is an explanatory diagram showing a fifth application example of a composite display device according to one embodiment of the present invention, in which (A) shows a state in which a clock display is arranged on a specific portion of the display unit, (B) shows an example of a projected color pattern display, and (C) shows a state in which the clock display is made to stand out. [Figure 9] FIG. 2 is a schematic diagram of a first modified example of an embodiment of the present invention. [Figure 10] FIG. 11 is a schematic diagram of a second modified example of an embodiment of the present invention. [Figure 11] FIG. 11 is a schematic diagram of a third modified example of an embodiment of the present invention. [Figure 12] FIG. 11 is a schematic diagram of a fourth modified example of an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a composite display device according to the present invention will be described in detail with reference to the drawings. In this embodiment, an electrophoretic display device 12 capable of displaying black and white images using an electrophoretic medium is employed as a monochrome display device constituting the main part of a composite display device 10 as shown in FIG. This electrophoretic display device 12 has a structure in which two types of particles, white particles WP and black particles BP, together with an insulating liquid IL, are encapsulated in microcapsules 31 as shown in Figure 2, each having a diameter of several tens of microns, and a power source 35 for applying a voltage is connected between a base-end electrode 33 supported by a support layer 32 and a transparent electrode 34 arranged on the inside of a transparent surface layer 36.

[0035] The polarity of the voltage from the power source 35 can be changed as desired to display either the white particles WP or the black particles BP attracted to the transparent electrode 34 side on the surface layer 36. By driving the microcapsules 31 with an electric field generated by the power source 35 in this way, the electrophoretic display device 12 can achieve a reflective display with ultra-low power consumption, and this technology is also a representative display technology for realizing electronic paper.

[0036] The electrophoretic display device 12 is configured by arranging a plurality of display units 14, each capable of displaying an arbitrary white display area WH and a black display area BL, vertically and horizontally, as shown in Fig. 3, using white fine particles WP and black fine particles BP, on, for example, a wall surface 28. The display unit 14 is, for example, 10 cm square, and has a total of 100 display units 14A, each 1 cm square, capable of arbitrarily displaying either black or white, arranged vertically and horizontally, as shown in Fig. 3. Accordingly, the electrophoretic display device 12 has a large number of display units 14, by arranging a plurality of display units 14, each capable of individually displaying black and white images, vertically and horizontally, as shown in Fig. 3.

[0037] 1, a projector device 16 capable of projecting a color image is disposed opposite the electrophoretic display device 12, and is capable of projecting projection light L of any color image onto each display unit 14. Furthermore, the multiple display units 14 of the electrophoretic display device 12 and the projector device 16 are each connected to a controller 18, which is a control device, and the controller 18 controls the operations of each display unit 14 and the projector device 16 to be synchronized in such a way that a color image that the projector device 16 can project corresponds to a black-and-white image that the electrophoretic display device 12 can display.

[0038] Therefore, the composite display device 10 of this embodiment makes it possible for each display unit 14 of the electrophoretic display device 12 to display any black and white image while being controlled by the controller 18, and for the projector device 16 to project a color image that corresponds to this black and white image and that is to be displayed onto each display unit 14 while being controlled by the controller 18.

[0039] On the other hand, the controller 18 is connected to a CPU 22 of a personal computer 20, which has a data storage device 24 made up of an SSD or a hard disk for storing pairs of black-and-white images to be displayed on the electrophoretic display device 12 and color images to be projected from the projector device 16. Furthermore, the personal computer 20 has an input / output device 26 equipped with a display or the like for creating black-and-white images and color images and for enabling inputting the images from outside, as well as for deleting black-and-white images and color images that are no longer necessary.

[0040] Next, the operation of the composite display device 10 of this embodiment will be described. 1, in the composite display device 10 according to this embodiment, an electrophoretic display device 12 has a plurality of display sections 14 arranged side by side, each of which can display any black and white image using black and white particles, and a projector device 16 irradiates each of the display sections 14 with projection light L of a color image. However, this electrophoretic display device 12 is of a reflective type using an electrophoretic medium. In other words, by adopting a reflective display device using an electrophoretic medium in this way, the composite display device 10 can be easily fabricated.

[0041] Furthermore, a controller 18 connected to a personal computer 20 controls the operation of the multiple display units 14 and the projector device 16, so that each display unit 14 can display an arbitrary black and white image while being controlled by the controller 18, and the projector device 16 can project a color image that corresponds to this black and white image and that should be displayed, onto the display unit 14.

[0042] In this case, to apply this composite display device 10 to a large display screen such as that installed on a wall surface 28 as shown in Figure 3, any number of display units, each of which is a display unit 14 and is approximately 10 cm square, can be arranged on the wall surface, and projection light L of a color corresponding to a color image can be projected onto all or part of such a large display screen using a projector device 16.

[0043] Therefore, according to this embodiment, by combining an electrophoretic display device 12 and a projector device 16 so that colored light is projected from the projector device 16 onto the screen of each display unit 14 of the electrophoretic display device 12, which has only a black and white display function, a composite display device 10 is constructed that can achieve the same color display effect as when a color filter is placed on each display unit 14.

[0044] Accordingly, the composite display device 10 of this embodiment solves the problems of the complexity of the manufacturing process and increased manufacturing costs due to the arrangement of color filters on the screen surface of the electrophoretic display device 12, and also solves the problem of reduced display brightness due to the arrangement of color filters by increasing the amount of light provided by the projector device 16.

[0045] As described above, according to this embodiment, not only is it possible to obtain a composite display device 10 that can be made large-screen without complicating the device for color display, while taking advantage of the energy-saving properties of the electrophoretic display device 12 that can only display black and white, and the brightness and clarity of the display in bright outdoor locations, but also the color display achieved by combining the projector device 16 and the reflective electrophoretic display device 12 is significantly more energy-efficient than emissive color display using an LED display device or LCD display device.

[0046] Next, specific examples of display and projection applications of the composite display device 10 of this embodiment will be described below. The first application example can be as follows. In this application example, the projector device 16 emits projection light L in a color pattern in which the three primary colors of light, red R, green G, and blue B, as shown in FIG. 4(B), are sequentially repeated in a manner that matches the size and arrangement period of pixels having white display areas WH and black display areas BL as shown in FIG. 4(A), which are the aforementioned 1 cm square display units 14A in each display section 14 constituting the electrophoretic display device 12.

[0047] Accordingly, by displaying, for example, red R on each white display area WH, which is the display unit 14A of the display section 14, a red R figure as shown in Fig. 4(C) is displayed. In other words, various color images that are originally required by the electrophoretic display device 12 formed by each display section 14 can be displayed in color on the electrophoretic display device 12 by combining each of the colors red, green, and blue with the white display area WH of each display section 14.

[0048] The second application example can be as follows. 1 projects a color image to be displayed onto each display unit 14, and each display unit 14 controlled by a controller 18 displays a black-and-white image that is displayed by extracting only the brightness component corresponding to the color image. In this application example, a color image to be displayed is projected onto the display unit 14, and a black-and-white image that is displayed by extracting only the brightness component of the color image is displayed on this display unit 14. Thus, even when using the projector device 16, an image that expresses the light and dark of a color image, including black, with a higher contrast can be obtained, unlike when an image is projected onto a projection screen surface that is white, silver, or the like.

[0049] For example, when it is desired to display a "red lamp on a dark night" image in which the light of a red lamp shines vividly against a dark night background, rather than simply projecting a red lamp light image onto a white screen, a black and white lamp light image with only the brightness component extracted as shown in FIG. 5(A) is displayed on the reflective medium of the display unit 14. In this case, the surrounding display units 14A are made into black display areas BL, and a white display area WH of the cross-shaped display units 14A is placed in the center. Then, by projecting a red lamp image from the projector device 16 as shown in FIG. 5(B) onto the cross-shaped white display area WH of the display unit 14 in a superimposed manner, this part becomes red R, and a clearer "red lamp on a dark night" image can be displayed.

[0050] Although the pixel arrangement pitch of the display pixels of each display unit 14 and the projection color pattern of the projector device 16 are matched, this is not essential, and a size relationship in which, for example, four pixels of the projection pattern of the projector device 16 are arranged for one pixel of the reflective display unit constituting each display unit 14 may also be acceptable.

[0051] The third application example is as follows. In this application example, a black-and-white image D1 like a line drawing in a coloring book is displayed on the display unit 14 of the electrophoretic display device 12 as shown in Fig. 6(A), and colored light D2 like coloring in a coloring book is projected from the projector device 16 in accordance with the black-and-white image as shown in Fig. 6(B) under the control of the controller 18. This makes it possible to clearly express the color differences and contours of the color image, which could not be fully expressed by projecting a color image from the projector device 16, as shown in Fig. 6(C), and a clear image D3 is obtained. In other words, this application example is suitable for the purpose of vividly displaying color illustrations, color patterns, etc.

[0052] The fourth application example is as follows. In this application example, an arbitrary black-and-white image is displayed on the electrophoretic display device 12, and the projector device 16 projects, for example, a striped pattern or a houndstooth pattern in which the three primary colors of light or the seven colors of the rainbow are arranged onto the electrophoretic display device 12. Specifically, characters are displayed on the electrophoretic display device 12 as shown in Fig. 7(A), and the projector device 16 projects, for example, a striped pattern of red R, green G, blue B, white W, etc., as shown in Fig. 7(B). This makes it possible to add a color background to an arbitrary black-and-white image displayed on the electrophoretic display device 12 as shown in Fig. 7(C), thereby producing vividness in the display.

[0053] The fifth application example is as follows. In this application example, an identifiable display area that should be distinguished from other parts is arranged only in a part of the display unit 14 of the electrophoretic display device 12, and the identifiable display area can be emphasized by projecting a color image only onto the identifiable display area from the projector device 16. In other words, a specific color light is projected from the projector device 16 only onto the identifiable display area, which is a specific part of the display unit 14 of the electrophoretic display device 12, to make the display content of that part stand out.

[0054] For example, in addition to displaying characters as shown in Fig. 8(A), a digital numerical value display or an analog needle clock display D4, which is an identifiable display area, is placed in a specific portion of each display unit 14, and a colored light that fills the portion with a conspicuous color, for example, yellow Y, is irradiated from the projector device 16 as shown in Fig. 8(B). Accordingly, the color yellow Y is applied only to the clock display D4, making it conspicuous and easy to read as shown in Fig. 8(C).

[0055] Next, a modified example of the control system in the composite display device 10 of this embodiment will be described. 9, a first control unit 42 that controls an electrophoretic display device 12 that displays a black-and-white image is connected to the electrophoretic display device 12 via a supply line 44. Meanwhile, a second control unit 46 that controls a projector device 16 that irradiates the electrophoretic display device 12 with projection light is connected to the projector device 16 via a supply line 48. The first control unit 42 and the second control unit 46 are connected by wire via a synchronization supply line 50.

[0056] For this reason, in this modification, the first control unit 42 and the second control unit 46 are connected by a wired connection using the synchronization supply line 50, making it possible to synchronize the operation of the electrophoretic display device 12 with the operation of the projector device 16. In this case, the synchronization signal may be supplied by sending a signal from the electrophoretic display device 12 to the projector device 16, or may be sent from the projector device 16 to the electrophoretic display device 12. The first control unit 42 and the second control unit 46 are regarded as control devices in this modification.

[0057] 10, in the same manner as in the first modification, the first control unit 42 and the electrophoretic display device 12 are connected, and the second control unit 46 and the projector device 16 are connected. However, in this modification, instead of a wired connection, the first control unit 42 and the second control unit 46 are connected via wireless transceivers 52, 54, and the black-and-white image of the electrophoretic display device 12 and the color image of the projector device 16 are controlled to be synchronized by wireless signals RS transmitted and received by these wireless transceivers 52, 54.

[0058] For this reason, in this modified example, the first control unit 42 and the second control unit 46 are connected wirelessly, making it possible to synchronize the operation of the electrophoretic display device 12 and the operation of the projector device 16. In this case, the synchronization signal may be supplied by sending a signal from the electrophoretic display device 12 to the projector device 16, or by sending a signal from the projector device 16 to the electrophoretic display device 12.

[0059] In the third modified example, as in the first modified example, as shown in Fig. 11, the first control unit 42 and the electrophoretic display device 12 are connected, and the second control unit 46 and the projector device 16 are connected. However, in this modified example, an electrophoretic display side light receiving sensor 56 is disposed on the surface of the electrophoretic display device 12, and a synchronization light serving as a control signal is transmitted to the electrophoretic display side light receiving sensor 56 as the projector device 16 irradiates the projection light L. Therefore, in this modified example, the first control unit 42 and the second control unit 46 are connected by wireless connection, and it is possible to synchronize the operation of the electrophoretic display device 12 and the operation of the projector device 16. In this case, the electrophoretic display side light receiving sensor 56 may be a simple light intensity sensor, but may also be a camera unit.

[0060] 12, in the same manner as in the first modification, the first control unit 42 and the electrophoretic display device 12 are connected, and the second control unit 46 and the projector device 16 are connected. However, in this modification, a projector-side light receiving sensor 58 is disposed in the second control unit 46 of the projector device 16, and the black-and-white image displayed on the electrophoretic display device 12 is detected by this projector-side light receiving sensor 58, and the second control unit 46 appropriately determines the color image to be sent from the projector device 16. In this case, the projector-side light receiving sensor 58 may be a simple light intensity sensor, but may also be a camera unit.

[0061] Next, it will be explained that the composite display device 10 of this embodiment is capable of displaying black and white using only the electrophoretic display device 12 even when the projector device 16 capable of displaying color is not always used in combination. In other words, the operating power of projector device 16 can be reduced by using projector device 16 only when necessary, and further, the operating power of projector device 16 can be reduced by using projector device 16 only when and where necessary on the display screen. Therefore, it is possible to reduce the operating power consumption compared to the case where color display is always performed by simply arranging projector device 16 on a screen or wall surface.

[0062] Furthermore, when used in a bright environment such as outdoors, the vividness of the color expression may decrease, but the clarity of the characters and illustrations can be maintained as a black and white screen. Outdoors, practical operation is possible in which the display is mainly black and white during the day and color display after sunset. In addition, the reflective display device 12 such as an electrophoretic display device cannot be made visible at night unless the display surface is illuminated, as with printed matter. However, by irradiating the display surface of the reflective display device with, for example, white light from the projector device 16, which is a component of the present invention, it is possible to make the display visible even at night. In this case, the light irradiated from the projector device 16 may be white light or any other color or pattern.

[0063] On the other hand, in the event of a power outage due to a disaster or the like, the use of the projector device 16 can be stopped, making use of the ultra-power saving properties of the electrophoretic display device 12 so that the black and white information display can be maintained with a minute supply of power from a small auxiliary battery or a solar power generation panel. Such an electrophoretic display device 12 can contribute to the safety and security of society by serving as an emergency source of information such as information on approaching tsunamis during a disaster.

[0064] In the above embodiment, an electrophoretic display device capable of displaying black and white images using an electrophoretic medium is used as a monochrome display device to make the specific means easier to understand, but the above effects can be obtained in the same way as long as the display method used on the projection surface is a reflective display device, so there is no need to be limited to the use of an electrophoretic display device, and a reflective display device other than an electrophoretic display device may be used. For example, various reflective liquid crystal display devices, electrowetting display devices, cholesteric liquid crystal display devices, etc. may be used.

[0065] On the other hand, there are various possible color combinations in the first application example described above, but typically, three colors are generally assumed to be Red, Green, Blue or Cyan, Magenta, Yellow. Also, four colors are generally assumed to be Red, Green, Blue, Yellow or Red, Green, Blue, White or Cyan, Magenta, Yellow, White. Furthermore, six colors are generally assumed to be Red, Green, Blue, Cyan, Magenta, Yellow. Incidentally, in the mosaic color filters built into color LCD displays, in addition to Red, Green, and Blue, combinations of Red, Green, Blue, Yellow and Red, Green, Blue, and White are also commonly used.

[0066] In addition, in the above embodiment, the first control unit 42 that controls the electrophoretic display device 12 and the second control unit 46 that controls the projector device 16 are synchronized, but it is also possible to not synchronize them.

[0067] Although the embodiment of the present invention has been described above, the present invention is not limited to the embodiment, and various modifications can be made without departing from the spirit of the present invention. [Industrial Applicability]

[0068] The present invention can be applied to a variety of industrial fields, such as indoor display devices as well as large-screen outdoor display devices. [Explanation of symbols]

[0069] 10 Composite display device 12 Electrophoretic display device (monochrome display device) 14 Display section 16 Projector equipment 18 Controller 42 First control unit (control device) 46 Second control unit (control device) 56 Electrophoretic display side light receiving sensor 58 Projector side light receiving sensor WH White display area BL Black display area L projection light

Claims

1. A monochrome display device in which a plurality of display units capable of displaying any desired black and white image are arranged side by side; a projector device capable of projecting a color image onto a display unit; a control device that controls operations of a plurality of display units of the monochrome display device and the projector device; A composite display device having: The display unit is controlled by a control device to display an arbitrary black-and-white image, and the projector device is controlled by the control device to project a color image that corresponds to the black-and-white image and is to be displayed onto the display unit.

2. 2. A composite display device according to claim 1, wherein the monochrome display device is a reflective electrophoretic display device using an electrophoretic medium.

3. 2. A composite display device as described in claim 1, wherein a projector device projects a color pattern of three or more colors in a repeated arrangement on each display section in response to the pixel size and arrangement period of each display section constituting the monochrome display device, thereby making it possible to display the color on the white displayed parts of each display section.

4. 2. A composite display device as claimed in claim 1, wherein a projector device projects a colour image to be displayed on each display unit, and each display unit controlled by a control device displays a black-and-white image by extracting only the brightness component corresponding to the colour image.

5. 2. A composite display device as claimed in claim 1, in which a black-and-white image such as a line drawing in a colouring book is displayed on the display section of the monochrome display device, and coloured light, as if colouring a colouring book, is projected from the projector device in accordance with the black-and-white image under the control of the control device.

6. 2. A composite display device according to claim 1, wherein an arbitrary black-and-white image is displayed on the display section of the monochrome display device, and a pattern in which various colors are arranged is projected onto the display section by the projector device.

7. 2. The composite display device according to claim 1, wherein an identification display area to be distinguished from other areas is arranged only on a part of the display section of the monochrome display device, and the identification display area can be emphasized by projecting a color image from a projector device onto the identification display area.

8. 2. A composite display device as described in claim 1, wherein a light receiving sensor connected to the control device is disposed on either the surface of the monochrome display device or the projector device, and as the light receiving sensor receives light to be synchronized, the display unit displays a black and white image and the projector device projects a color image while being controlled by the control device.

Images