Display device

Abstract

To provide a display device capable of surely preventing the color and pattern of a surface visible at the time of non-use from being visible at the time of use.SOLUTION: The video display device 100 includes an electronic paper 120 capable of switching between black and a predetermined pattern in response to application of a voltage and having a plurality of openings, a display panel 114 disposed on the back side of the electronic paper 120 and adjacent to a position where display content is visible through the plurality of openings, a backlight 116, and the like, and a control unit 130 that switches the electronic paper 120 to a black display state when the display panel 114 is turned on and switches the electronic paper 120 to a pattern display state when the display panel 114 is turned off.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a display device that allows a predetermined pattern to be seen when not in use. [Background technology]

[0002] There has long been a demand for in-vehicle displays to be invisible, and to meet this demand, a display device is known that provides necessary visual information when in use and makes it appear as if the display is not present when not in use, thereby not spoiling the aesthetics of the area where it is attached (see, for example, Patent Document 1). This display device uses a screen printed in the same wood-grain color and pattern as the surrounding wood-grain panel, and when in use, images are displayed by transmitting light from the display forward through the many fine holes in the screen, and when not in use, the wood-grain color and pattern of the screen can be seen. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-331132 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the above-mentioned Patent Document 1 includes a description that the color and pattern of the screen are not a visual obstacle when in use because they are obscured by the brightness of the display light transmitted through the micropores, and therefore the presence of the screen does not pose any visual obstacle, and the image on the display can be viewed without being bothered by the presence of the screen. However, in reality, the brightness of each part of the image on the display varies depending on the displayed content, so there is a problem in that the woodgrain color and pattern cannot be completely erased in dark areas.

[0005] The present invention was created in consideration of these points, and its purpose is to provide a display device that can reliably make the surface color and pattern visible when not in use invisible when in use. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the display device of the present invention comprises a first display means having a plurality of openings and capable of switching between black and a predetermined pattern in response to the application of a voltage, a second display means arranged adjacent to the back side of the first display means in a position where the display content can be seen through the plurality of openings, and a switching means which switches the first display means to a black display state when the second display means is lit and to a pattern display state when the second display means is not lit.

[0007] Since the first display means displays black while an image is being displayed by the second display means, it is possible to reliably prevent the pattern that appears when the device is not in use (when the second display means is not lit) from being visible when the device is in use (when the second display means is lit).

[0008] Furthermore, it is desirable that the first display means be electronic paper that maintains the display state of the pattern when the application of voltage is stopped, thereby making it possible to reduce power consumption when the device is not in use and the predetermined pattern is visible.

[0009] Furthermore, it is desirable that the above-mentioned pattern be a wood-grain pattern, which will reliably hide unnecessary patterns while the screen is displayed, and will provide a wood-grain appearance when the screen is not displayed, thereby enabling the creation of a luxurious feel.

[0010] It is also desirable that the first display device be arranged so as to overlap the black matrix of the second display means, thereby enabling a pattern to be displayed when not in use without reducing the screen display area. [Brief explanation of the drawings]

[0011] [Figure 1]1 is a diagram illustrating a configuration of a video display device according to an embodiment. [Figure 2] FIG. 2 is a diagram showing the positional relationship between electronic paper and a display panel. [Figure 3] FIG. 2 is a diagram showing a display state of electronic paper. [Figure 4] 10 is a flowchart showing an operation procedure for switching the display content of the electronic paper. [Figure 5] 10A and 10B are diagrams illustrating display states of other electronic paper devices with different driving methods. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an image display device according to an embodiment of the present invention will be described with reference to the drawings.

[0013] Fig. 1 is a diagram showing the configuration of an image display device according to an embodiment. The image display device 100 shown in Fig. 1 is incorporated into, for example, a head unit mounted in a vehicle, is placed in the dashboard, and displays images based on a video signal output from a head unit main body (not shown). Note that this usage is merely an example, and the image display device 100 may be used in a form separate from the head unit main body, or may be used for purposes other than the head unit or for purposes other than the vehicle.

[0014] The image display device 100 includes an image signal receiving unit 110, a display driver 112, a display panel 114, a backlight 116, a backlight driver 118, electronic paper 120, and a control unit .

[0015] The video signal receiving unit 110 receives a video signal in LVDS (Low Voltage Differential Signaling) format input from the head unit body via a video input terminal, performs serial / parallel conversion on the received signal, and outputs a video signal in RGB format.

[0016] Display driver 112 drives display panel 114 based on the RGB video signal output from video signal receiving unit 110, and displays the image represented by this video signal. Display panel 114 is, for example, a color liquid crystal display panel, and is assembled facing backlight 116 that illuminates from behind. Backlight 116 is formed of, for example, LEDs, and a drive voltage is PWM (Pulse Width Modulation) controlled by backlight driver 118 to achieve a predetermined brightness.

[0017] The electronic paper 120 can be switched between black and a predetermined pattern in response to the application of a voltage. The electronic paper 120 is disposed on the surface of the display panel 114.

[0018] 2 is a diagram showing the positional relationship between electronic paper 120 and display panel 114. Electronic paper 120 is disposed on the surface of display panel 114 and has a plurality of openings 120A. These openings 120A correspond to the respective display pixels 114A of display panel 114, and a user can view the respective display pixels 114A of display panel 114 through these openings 120A. Furthermore, electronic paper 120 is disposed so that the portion excluding openings 120A overlaps black matrix (BM) 114B of display panel 114.

[0019] The control unit 130 controls the entire image display device 100. The control unit 130 is connected to the head unit main body via a communication terminal, and transmits and receives various data to and from the head unit main body by communication according to, for example, the CAN (Controller Area Network) protocol.

[0020] Furthermore, control unit 130 switches the display content of electronic paper 120 in conjunction with the image display operation using display panel 114. For example, while an image is being displayed using display panel 114 (when in use, when lit), a drive voltage is applied so that the screen of electronic paper 120 turns black. On the other hand, after image display using display panel 114 has ended or before it starts (when not in use, when not lit), a drive voltage is applied so that the screen of electronic paper 120 turns into a predetermined pattern (for example, a wood-grain color or pattern). Note that electronic paper 120 has a memory property that allows it to retain the display content up to that point even after the application of voltage is stopped, and therefore application of the drive voltage is stopped after the screen has switched to black or the predetermined pattern.

[0021] The electronic paper 120 described above corresponds to a first display means, the display panel 114, the backlight 116, and the backlight driver 118 correspond to a second display means, and the control unit 130 corresponds to a switching means.

[0022] The image display device 100 of this embodiment has the above-described configuration. Next, an operation of switching the display content of the electronic paper 120 in response to the lighting / non-lighting of the display panel 114 will be described.

[0023] 3A and 3B are diagrams showing the display state of the electronic paper 120. For example, in the case of using an electrophoretic system, Fig. 3A shows the display state when the display panel 114 is not lit, and Fig. 3B shows the display state when the display panel 114 is lit.

[0024] In electronic paper 120, oil 12 is sealed in microcapsules 10, and this oil 12 contains negatively charged black particles 14 and positively charged particles 16 of a color required to draw a predetermined pattern, such as wood grain. Two pixel electrodes 20 and 22 are arranged on either side of this microcapsule 10.

[0025] When the display panel 114 is not lit, if a voltage is applied so that the pixel electrode 20 located on the user side is negative and the pixel electrode 22 on the opposite side is positive (FIG. 3(A)), the positively charged particles 16 move to the surface (user side), causing a predetermined pattern to be visible to the user. Note that this voltage application is necessary to move the particles 14, 16, and the displayed woodgrain pattern or other pattern will be maintained even if the voltage application is subsequently stopped.

[0026] Conversely, when the display panel 114 is turned on, if a voltage is applied so that the pixel electrode 20 located on the user side is positive and the pixel electrode 22 on the opposite side is negative (FIG. 3(B)), the negatively charged black particles 14 move to the surface (user side), causing the display to turn black and preventing the user from seeing the specified pattern. This black color is the same as the black matrix of the display panel 114, and the user will only see the color of the display pixel 114A of the display panel 114. Note that this voltage application is necessary to move the particles 14, 16, and the displayed black color will be maintained even if the voltage application is subsequently stopped.

[0027] 4 is a flowchart showing the operation procedure for switching the display content of electronic paper 120. Before power is applied to image display device 100 (when display panel 114 is not lit), electronic paper 120 maintains a screen displaying a predetermined pattern such as woodgrain.

[0028] When the image display device 100 is powered on and starts operating, the control unit 130 first applies a voltage to the electronic paper 120 as shown in Fig. 3(B) to switch the electronic paper 120 to a black display (step 100). After the switch, the voltage application is stopped (step 102). Thereafter, a display operation using the display panel 114 is performed (step 104).

[0029] In parallel with this display operation, the control unit 130 determines whether an instruction to end the display (for example, an operation to turn off the power) has been given (step 106). If an instruction to end the display has not been given, a negative determination is made, and the process returns to step 104 to continue the display operation. If an instruction to end the display has been given, a positive determination is made in the determination of step 106, and the display operation using the display panel 114 ends (step 108).

[0030] Next, the control unit 130 applies a voltage to the electronic paper 120 as shown in Figure 3(A) to switch the electronic paper 120 to display a pattern such as wood grain (step 110). After switching, the voltage application is stopped (step 112).

[0031] In this way, in the image display device 100 of this embodiment, the electronic paper 120 displays black while the display panel 114 is displaying an image, so that the pattern when not in use can be reliably prevented from being seen when in use.

[0032] Furthermore, electronic paper 120 can maintain the black or pattern display state when the application of voltage is stopped, making it possible to reduce power consumption when the pattern display state is in use.

[0033] Furthermore, by using a wood grain pattern when not in use, it is possible to create a sense of luxury when not in use.

[0034] Furthermore, since electronic paper 120 is arranged overlapping black matrix 114B of display panel 114, it is possible to display a pattern when not in use without reducing the screen display area of ​​display panel 114.

[0035] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention. In the above-described embodiment, a driving method is used in which particles 14 and the like are moved by an electric field perpendicular to the display surface of electronic paper 120, as shown in Fig. 3, but electronic paper using other driving methods may be used as long as the particles 14 and the like can be moved.

[0036] 5A and 5B are diagrams showing the display state of another electronic paper 120A using a different driving method. For example, in the case of using an electrophoretic method, Fig. 5A shows the display state when the display panel 114 is not lit, and Fig. 5B shows the display state when the display panel 114 is lit. Pixel electrodes 30 are arranged along the black matrix 114B of the display panel 114, and common electrodes 32 are arranged at the ends of the pixel electrodes 30.

[0037] When the display panel 114 is off, if a voltage is applied so that the pixel electrode 30 is positive relative to the common electrode 32 (FIG. 5(A)), the positively charged black particles 18 move laterally toward the common electrode 32. For example, by drawing a predetermined pattern on the pixel electrode 30, or by constructing the pixel electrode 30 from a transparent electrode and exposing the pattern underneath, the user can see the pattern. Note that this voltage application is necessary to move the particles 18, and the displayed woodgrain pattern or other pattern will be maintained even if the voltage application is subsequently stopped.

[0038] Conversely, when the display panel 114 is turned on, if a voltage is applied so that the pixel electrode 30 is negative with respect to the common electrode 32 (FIG. 5(B)), the positively charged black particles 16 migrate to the surface of the pixel electrode 30, causing the pixel electrode 30 to turn black and making the specified pattern invisible to the user. This black color is the same as the black matrix of the display panel 114, and the user only sees the color of the display pixels 114A of the display panel 114. Note that application of such a voltage is necessary to move the particles 18, and the displayed black color is maintained even if the application of the voltage is subsequently stopped.

[0039] In addition, in the above-described embodiment, patterns such as wood grain are displayed by devising the color of the particles 16, but it is also possible to display a pattern of a specific color through a color filter, for example.

[0040] Furthermore, in the above-described embodiment, the case where the electrophoretic electronic paper 120 is used has been described, but electronic paper of other driving types, such as an electronic liquid powder type, may also be used. [Industrial Applicability]

[0041] As described above, according to the present invention, the first display means (electronic paper 120) displays in black while an image is being displayed by the second display means (display panel 114), thereby reliably preventing patterns such as wood grain from being visible when not in use while an image is being displayed. [Explanation of symbols]

[0042] 10 Microcapsules 12 Oil 14, 16 particles 20, 22 Pixel electrodes 100 Video display device 110 Video signal receiving unit 112 Display Driver 114 Display Panel 114A display pixel 114B Black Matrix (BM) 116 Backlight 118 Backlight Driver 120 Electronic Paper 120A aperture 130 Control Unit

Claims

1. a first display means having a plurality of apertures and capable of switching between black and a predetermined pattern in response to application of a voltage; a second display means disposed adjacent to the first display means at a position on the rear side thereof where the display content can be seen through the plurality of openings; a switching means for switching the first display means to a black display state when the second display means is lit, and for switching the first display means to a pattern display state when the second display means is not lit; A display device comprising:

2. 2. The display device according to claim 1, wherein the first display means is electronic paper, and maintains the pattern display state when the application of voltage is stopped.

3. 2. The display device according to claim 1, wherein the pattern is a wood grain pattern.

4. 2. The display device according to claim 1, wherein the first display device is disposed so as to overlap a black matrix of the second display means.

Images