Image display device

Abstract

Provided are a liquid crystal panel capable of controlling a field angle while suppressing the thickness, and a video display device provided with the liquid crystal panel. This image display device is provided with a display panel for displaying an image, and a liquid crystal panel, the display panel being provided with at least a polarizing plate, the polarizing plate provided in the display panel being disposed facing the display panel side of the liquid crystal panel. The liquid crystal panel is provided with an electrode A disposed between a pair of transparent substrates with a gap therebetween in plan view, a liquid crystal layer, and an electrode B disposed facing the electrode A with the liquid crystal layer therebetween, and is provided with a voltage application means for applying a voltage between the electrode A and the electrode B. The liquid crystal layer is a guest-host liquid crystal layer containing a dichroic dye and liquid crystal molecules. The polarizer is provided with an overlapping region overlapping the electrode A and a non-overlapping region not overlapping the electrode A. In plan view, the transmission axis of the polarizer is substantially perpendicular to the initial orientation direction of the liquid crystal molecules.

Description

Technical Field

[0001] The following disclosure relates to an image display device. Background Art

[0002] Liquid crystal panels, which are the main components of image display devices, are usually composed of a structure in which a liquid crystal layer is sealed between a pair of substrates. A voltage is applied to the liquid crystal layer, and the orientation state of the liquid crystal molecules changes accordingly with the applied voltage, thereby controlling the amount of light transmitted. Such liquid crystal panels effectively utilize the characteristics of thinness, light weight and low power consumption, and are widely used in various applications.

[0003] In recent years, in image display devices, research is being conducted to improve the viewing angle characteristics so that the same image can be observed whether it is observed from a narrow viewing angle range or a wide viewing angle range. On the other hand, from the perspective of maintaining privacy, research is being conducted on display methods in which an image can be observed from a narrow viewing angle range, but the image is difficult to be observed from a wide viewing angle range. Thus, a display device is required that can switch between a public mode (also called a wide viewing angle mode) in which the same image can be observed from a narrow viewing angle range or a wide viewing angle range, and a privacy mode (also called a narrow viewing angle mode) in which the image can be observed from a narrow viewing angle range but the image is difficult to be observed from a wide viewing angle range.

[0004] Regarding the technology of switching the viewing angle mode, for example, Patent Document 1 discloses a display device having a liquid crystal display element, a light source, and an optical element arranged therebetween. As the optical element, a first region composed of a light-transmitting material is provided between a pair of transparent substrates, and a second region containing a composite material that selectively switches between the light-transmitting state and the scattering or absorption state arranged between the first region is exemplified, and the composite material is composed of a material to which a dichroic black pigment is added to a polymer dispersed liquid crystal. Patent Document 2 discloses an image display element in which a viewing angle control element is arranged on the front surface of an image display element, and as the viewing angle control element, a first region having a certain transmittance opposite to a pixel and a second region that can switch between a certain transmittance and a certain transmittance smaller than the first region is exemplified, and the second region (light-shielding region) is formed by a guest-host liquid crystal of a dichroic pigment.

[0005] Patent document 3 discloses a display device having a viewing angle control device and a display device having a polarizing plate on the device side, wherein the viewing angle control device has a liquid crystal layer to which a dichroic pigment is added and a drive circuit capable of switching the display state by changing the arrangement state of the liquid crystal molecules in the liquid crystal layer. Patent document 4 discloses a display panel having a first display, a second display having a liquid crystal layer sandwiched between a pair of electrodes, and a polarizing plate sandwiched between them, wherein the liquid crystal layer of the second display is a guest-host liquid crystal unit having liquid crystal molecules as a host and pigment molecules as a guest, and the long axis direction of the liquid crystal molecules is parallel to the long axis direction of the pigment molecules. Prior art literature Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2007-206373 Patent Document 2: Japanese Patent Application Publication No. 2005-221756 Patent Document 3: International Patent Publication No. 2008 / 047754 Patent Document 4: U.S. Patent Application Publication No. 2020 / 0064666 Summary of the invention Technical Problems to be Solved by the Invention

[0007] Fig. 27 FIG. 1 is a cross-sectional schematic diagram of a certain image display device 1R discovered by the applicant of the present application. Fig. 27 As shown, the image display device 1R includes a liquid crystal panel 20R, a display panel 10R, and a backlight 40 in order from the observation side toward the back side. An adhesive layer 150 for bonding them is provided between the display panel 10R and the liquid crystal panel 20R. The liquid crystal panel 20R includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240 containing a guest-host type liquid crystal in which a dichroic dye (guest) is added to a liquid crystal material (host), a second electrode 232, an interlayer insulating film 250, a third electrode 233, and a second transparent substrate 220 in order from the observation side. The display panel 10R includes a polarizer 141, a CF substrate 110 including a color filter (CF: Color Filter) layer, a liquid crystal layer 130, a TFT substrate 120 including a thin film transistor (TFT: Thin Film Transistor), and a polarizer 142 in order from the observation side.

[0008] The liquid crystal layer 240 of the liquid crystal panel 20R has an overlapping region 241 that overlaps with the second electrode 232, and a non-overlapping region 242 that does not overlap with the second electrode 232. The liquid crystal layer 240 is a guest-host (GH) type liquid crystal layer containing a dichroic pigment, and has the characteristic of having an overlapping region 241 and a non-overlapping region 242, so that the liquid crystal layer 240 has a transparent region and a switching region that switches between a transmission state and an absorption state. Such an image display device 1R has a function of controlling the viewing angle by applying or not applying a voltage to the liquid crystal layer 240, but in addition to this function, it also has a grid function in which the liquid crystal layer 240 itself functions as a grid. Therefore, the image display device 1R is extremely useful in the field of display devices.

[0009] However, the inventors of the present application have further studied the image display device 1R and found that the grille function may not be fully obtained depending on the polarization direction of light incident on the liquid crystal panel 20R from the back side. It was found that even if the image display device 1R includes the display panel 10R, the liquid crystal panel 20R and the backlight 40 in sequence from the observation side to the back side, the grille function may not be fully obtained. In this way, the inventors of the present application have found that there is still room for improvement in the extremely useful image display device 1R for more effectively controlling the viewing angle.

[0010] The inventors of the present application conducted a more detailed study and found that the reason is that among the light incident on the liquid crystal layer 240 (GH-type liquid crystal layer), the light that is orthogonal to the orientation direction of the liquid crystal molecules in the liquid crystal layer is not absorbed but transmitted. In this case, it is considered that in the liquid crystal layer 240, the absorption function based on the switching area and the transmission function based on the transparent area remain problems. Specifically, for example, consider a state where a voltage is applied between the first electrode 231 and the second electrode 232 (262), and no voltage is applied between the first electrode 231 and the third electrode 233 (261) (voltage application state), the switching area is not switched to the absorption state and all-directional light is transmitted (refer to Fig.28A ), or the transparent area also becomes an absorption state, blocking all light (refer to Fig.28B ). Fig.28A and Fig.28B This is a diagram showing a study of possible problems that a certain image display device 1R discovered by the applicant of the present application may have.

[0011] However, Patent Document 1 does not contain any record of research on the polarization direction of light incident on the optical element. In addition, in the optical element described in Patent Document 1, a first region in a light-transmitting state and a second region that selectively switches between a light-transmitting state and a scattering or absorption state are physically distinguished by making the materials used for these regions different. In the optical element described in Patent Document 1, it becomes difficult to narrow the viewing angle in a conventional liquid crystal process, or the manufacturing process becomes complicated, and there are various problems in practical application.

[0012] In the viewing angle control element described in Patent Document 2, a first area having a certain transmittance and a second area capable of switching transmittance are physically distinguished by making the materials used for these areas different. The viewing angle control element described in Patent Document 2 can achieve both a wide viewing angle and a narrow viewing angle, and prevents the image quality from being reduced due to the reduction in brightness of the image display element at a wide viewing angle, so it is extremely useful in the field of display devices. However, there is room for design to more effectively achieve viewing angle control.

[0013] The display described in Patent Document 3 can also adapt to various use environments and purposes by switching the display state between a wide viewing angle and a narrow viewing angle, and is therefore extremely useful in the field of display devices. However, in order to further increase the display brightness, there is room for designing to further reduce the transmission loss of light. In addition, in the display panel described in Patent Document 4, in addition to worrying about the reduction in image quality caused by the reduction in brightness at a wide viewing angle, there is room for designing to easily control the viewing angle.

[0014] The present invention has been made in view of the above-mentioned current situation, and an object of the present invention is to provide a liquid crystal panel capable of controlling a viewing angle while suppressing thickness, and an image display device including the liquid crystal panel. Means of solving the problem

[0015] (1) One embodiment of the present invention is an image display device, which comprises a display panel for displaying an image and a liquid crystal panel, the display panel comprising at least a polarizing plate, the polarizing plate of the display panel being arranged opposite to the display panel side of the liquid crystal panel, the liquid crystal panel comprising an electrode A arranged between a pair of transparent substrates with a gap when viewed from above, a liquid crystal layer, and an electrode B arranged opposite to the electrode A via the liquid crystal layer, and the liquid crystal panel comprising a voltage applying unit for applying a voltage between the electrode A and the electrode B, the liquid crystal layer being a guest-host type liquid crystal layer comprising a dichroic dye and liquid crystal molecules, and comprising an overlapping region overlapping with the electrode A, and a non-overlapping region not overlapping with the electrode A, and the transmission axis of the polarizing plate is approximately perpendicular to the initial orientation direction of the liquid crystal molecules when viewed from above.

[0016] (2) In addition, an embodiment of the present invention is an image display device, which is based on the above (1), wherein the liquid crystal layer has a transparent area and a switching area that switches between a transmission state and an absorption state.

[0017] (3) In addition, an embodiment of the present invention is an image display device, which is based on the above (2), wherein the transparent area and the switching area are formed of the same material.

[0018] (4) In addition, an embodiment of the present invention is an image display device, which is based on the above (1), (2) or (3), wherein the above-mentioned electrodes A are configured to have a stripe shape when viewed from above.

[0019] (5) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3) or the above (4), wherein the above-mentioned liquid crystal panel comprises a first transparent substrate, a first electrode, the above-mentioned liquid crystal layer, a second electrode, an interlayer insulating film, a third electrode and a second transparent substrate in sequence, the above-mentioned second electrode is the above-mentioned electrode A, the above-mentioned first electrode is the above-mentioned electrode B, and the above-mentioned liquid crystal panel also comprises a second voltage applying unit for applying a voltage between the above-mentioned first electrode and the above-mentioned third electrode.

[0020] (6) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3) or the above (4), wherein the above liquid crystal panel comprises a first transparent substrate, a first electrode, a first interlayer insulating film, a second electrode, the above liquid crystal layer, a third electrode, a second interlayer insulating film, a fourth electrode and a second transparent substrate in sequence, one of the above second electrode or the above third electrode is the above electrode A, and the other is the above electrode B, the above voltage applying unit is a unit for applying a voltage between the above second electrode and the above third electrode, and the above liquid crystal panel also comprises a third voltage applying unit for applying a voltage between the above first electrode and the above fourth electrode.

[0021] (7) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3) or the above (4), wherein the above liquid crystal panel comprises a first transparent substrate, a first electrode, a first interlayer insulating film, a second electrode, the above liquid crystal layer, a third electrode, a second interlayer insulating film, a fourth electrode and a second transparent substrate in sequence, at least one of the above second electrode or the above third electrode is the above electrode A, at least one of the above first electrode or the above fourth electrode is the above electrode B, and the above voltage applying unit includes a first voltage applying unit for applying a voltage between the above second electrode and the above fourth electrode, and a second voltage applying unit for applying a voltage between the above first electrode and the above third electrode.

[0022] (8) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3), the above (4), the above (5), the above (6) or the above (7), and the thickness of the above non-overlapping area is less than 30μm.

[0023] (9) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3), the above (4), the above (5), the above (6), the above (7) or the above (8), wherein the above electrode A and the above electrode B are transparent electrodes.

[0024] (10) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (5), (8) or (9), wherein the first electrode, the second electrode and the third electrode are transparent electrodes.

[0025] (11) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (6), the above (7), the above (8) or the above (9), and further includes a backlight.

[0026] (12) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3), the above (4), the above (5), the above (6), the above (7), the above (8), the above (9), the above (10) or the above (11), and also has a backlight source.

[0027] (13) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (12), and the above-mentioned backlight has a local dimming function.

[0028] (14) In addition, a certain embodiment of the present invention is an image display device, which is based on the above (1), the above (2), the above (3), the above (4), the above (5), the above (6), the above (7), the above (8), the above (9), the above (10), the above (11), the above (12) or the above (13), wherein the above display panel is a liquid crystal display panel or a self-luminous display panel. Effects of the Invention

[0029] According to the present invention, it is possible to provide a liquid crystal panel capable of controlling a viewing angle while suppressing thickness, and an image display device including the liquid crystal panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic cross-sectional view of the image display device according to the first embodiment. Figure 2AIt is a schematic cross-sectional view of the image display device according to the first embodiment. Figure 2B It is a schematic plan view showing the arrangement of the second electrodes 232 in the liquid crystal layer 240 included in the liquid crystal panel 20 according to the first embodiment. Figure 2C This is a diagram (plan schematic diagram) of the orientation (i) of the liquid crystal molecules 2401 in the liquid crystal layer 240 when no voltage is applied and the transmission axis direction (ii) of the polarizer 141 of the display panel 10, observed from directly above (observation side) with respect to the first embodiment and the third embodiment to the ninth embodiment. Figure 3A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the first embodiment. Figure 3B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the wide viewing angle mode in the image display device according to the first embodiment. Figure 4A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the first embodiment. Figure 4B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the first embodiment. Figure 4C This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the first embodiment. Figure 5A It is a schematic plan view showing a specific example of the stripe shape. Figure 5B It is a schematic plan view showing a specific example of the stripe shape. Figure 6 This is a conceptual diagram for explaining the thickness D of the non-overlapping region, the width W1 of the non-overlapping region, the width W2 of the overlapping region, and the viewing angle θ. Fig. 7A It is a schematic cross-sectional view of an image display device according to a second embodiment. Figure 7B This is a diagram (schematic plan view) regarding the second embodiment, showing the orientation (i) of liquid crystal molecules 2401 in a liquid crystal layer 240 when no voltage is applied and the transmission axis direction (ii) of a polarizing plate 141 included in a display panel 10 , as viewed from directly above (observation side). Fig. 8A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the second embodiment. Figure 8BThis is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the wide viewing angle mode in the image display device according to the second embodiment. Fig.9A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the second embodiment. Fig. 9B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the second embodiment. Fig.10 It is a schematic cross-sectional view of an image display device according to a third embodiment. Fig.11 It is a schematic cross-sectional view of an image display device according to a fourth embodiment. Fig.12 It is a schematic cross-sectional view of an image display device according to a modified example of the fourth embodiment. Fig.13 It is a schematic cross-sectional view of an image display device according to a fifth embodiment. Fig.14A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the fifth embodiment. Fig. 14B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the wide viewing angle mode in the image display device according to the fifth embodiment. Fig.15A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the fifth embodiment. Fig. 15B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the fifth embodiment. Fig. 15C This is an example of effective voltage application in the image display device according to the fifth embodiment. Fig.15D This is an example of effective voltage application in the image display device according to the fifth embodiment. Fig.15E This is an example of effective voltage application in the image display device according to the fifth embodiment. Fig.15F This is an example of effective voltage application in the image display device according to the fifth embodiment. Figure 15G This is an example of effective voltage application in the image display device according to the fifth embodiment. Fig.16 It is a schematic cross-sectional view of an image display device according to a sixth embodiment. Fig.17A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the sixth embodiment. Fig. 17B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the wide viewing angle mode in the image display device according to the sixth embodiment. Fig.18A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the sixth embodiment. Fig.18B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the sixth embodiment. Fig.19 It is a schematic cross-sectional view of an image display device according to a seventh embodiment. Fig. 20A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the seventh embodiment. Fig. 20B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the wide viewing angle mode in the image display device according to the seventh embodiment. Fig.21A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the seventh embodiment. Fig. 21B This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the seventh embodiment. Fig. 21C This is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 in the narrow viewing angle mode in the image display device according to the seventh embodiment. Fig. 22 It is a schematic cross-sectional view of an image display device according to an eighth embodiment. Fig.23A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of Example 1. Fig. 23B 1 is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of Example 1. Fig.24A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of Example 5. Fig. 24B This is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of Example 5. Fig.25A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of Example 6. Fig.25B This is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of Example 6. Fig.26A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of Example 7. Fig.26B This is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of Example 7. Fig. 27 It is a schematic cross-sectional view of a certain image display device 1R discovered by the applicant of the present application. Fig.28A This is a diagram that examines possible problems that the video display device 1R may have. Fig.28B This is a diagram that examines possible problems that the video display device 1R may have. DETAILED DESCRIPTION

[0031] (Definition of terms) In this specification, the observation side means a side closer to the screen (display surface) of the image display device, and the rear side means a side farther from the screen (display surface) of the image display device.

[0032] The polar angle refers to the angle between the direction of the object (e.g., the measurement direction) and the normal direction of the panel surface of the liquid crystal panel. The azimuth (φ) refers to the direction when the direction of the object is projected onto the screen of the liquid crystal panel, and is expressed by the angle (azimuth) between the direction that serves as the reference. Here, the reference azimuth (φ=0°) is set to the horizontal right direction of the screen of the liquid crystal panel. Angles and azimuths are set as positive angles when rotating counterclockwise from the reference azimuth, and as negative angles when rotating clockwise from the reference azimuth. Counterclockwise and clockwise both represent the rotation direction when observing the screen of the liquid crystal panel from the observation side (front). In addition, the angle represents the value measured when observing the screen of the liquid crystal panel from above.

[0033] The voltage-unapplied state refers to a state in which the applied voltage to the liquid crystal layer is less than the threshold voltage (including the voltage not being applied). The voltage-applied state refers to a state in which the applied voltage to the liquid crystal layer is greater than the threshold voltage. In this specification, the voltage-unapplied state is also referred to as the voltage-unapplied state, and the voltage-applied state is also referred to as the voltage-applied state.

[0034] The initial alignment direction of the liquid crystal molecules means the direction of the long axis of the liquid crystal molecules when no voltage is applied.

[0035] Hereinafter, an image display device according to an embodiment of the present invention will be described. The present invention is not limited to the contents described in the following embodiment, and the design can be appropriately changed within the scope of the configuration satisfying the present invention.

[0036] (First Embodiment) Figure 1 and Figure 2A It is a schematic cross-sectional view of the image display device of this embodiment. Figure 3A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the present embodiment. Figure 4A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the present embodiment.

[0037] like Figure 1 , Figure 2A , Figure 3A and Figure 4A As shown in FIG. 1 , the image display device 1 of the present embodiment includes a liquid crystal panel 20, a display panel 10 for displaying an image, and a backlight 40 in order from the observation side toward the back side. In the present embodiment, an image display device can be realized that can display an image on the display panel 10 using light from the backlight 40 and can control the viewing angle while suppressing the thickness. An adhesive layer 150 is usually provided between the display panel 10 and the liquid crystal panel 20 for bonding them.

[0038] <LCD Panel> like Figure 1 As shown, the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, an interlayer insulating film 250, a third electrode 233 and a second transparent substrate 220 in order from the observation side to the back side. The second electrode 232 is arranged at a distance when viewed from above, and the second electrode 232 and the first electrode 231 are arranged opposite to each other through the liquid crystal layer 240. The liquid crystal panel 20 also includes a first voltage applying unit 262 for applying a voltage between the first electrode 231 and the second electrode 232, and a second voltage applying unit 261 for applying a voltage between the first electrode 231 and the third electrode 233. The polarizing plate 141 provided by the display panel 10 is arranged opposite to the display panel 10 side of the liquid crystal panel 20 (the back side in this embodiment). In addition, since the liquid crystal panel 20 has the function of controlling the viewing angle, it can be called a "viewing angle control unit".

[0039] The first transparent substrate 210 and the second transparent substrate 220 may be any substrate as long as they are transparent to visible light, for example, a glass substrate, a plastic substrate, etc. may be mentioned.

[0040] The first electrode 231 is arranged in a planar shape on the entire surface of the first transparent substrate 210. That is, the first electrode 231 is a solid electrode that covers the first transparent substrate 210. As a result, the wide viewing angle mode and the narrow viewing angle mode can be switched over the entire liquid crystal panel. The first electrode 231 can be a transparent electrode. As a transparent electrode, for example, it can be formed of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof.

[0041] The second electrode 232 is arranged at intervals when viewed from above. In this specification, electrode A means an electrode arranged at intervals when viewed from above, and electrode B means an electrode arranged opposite to the electrode A via the liquid crystal layer 240. In this embodiment, the second electrode 232 corresponds to the electrode A, and the first electrode 231 corresponds to the electrode B. By arranging the second electrode 232 at intervals when viewed from above, the liquid crystal layer 240 has an overlapping region 241 that overlaps with the second electrode 232, and a non-overlapping region 242 that does not overlap with the second electrode.

[0042] In this embodiment, if Figure 2B As shown, the electrode A (the second electrode 232 in this embodiment) is arranged in a stripe shape (also called a slit shape) in a plan view. Figure 2B 2 is a schematic plan view showing the arrangement of the second electrode 232 (electrode A) in the liquid crystal layer 240 of the liquid crystal panel 20 of the present embodiment. Figure 5A The straight line shown, Figure 5B The Japanese character "く" is shown. Figure 5A and Figure 5B : is a schematic plan view showing a specific example of a stripe shape. By configuring the electrode A in a stripe shape when viewed from above, it is possible to fully ensure the switching area that can switch between the transmission state and the absorption state, so that the viewing angle in the left and right directions of the screen can be effectively controlled. On the other hand, when the electrode A is configured in a grid shape when viewed from above, for example, the switching area is reduced, and the switching effect between the transmission state and the absorption state cannot be fully obtained.

[0043] Here, overlapping with electrode A means directly or indirectly contacting with electrode A. As a method of indirectly contacting with electrode A, for example, there can be cited a method in which the overlapping region 241 contacts with electrode A via an alignment film. The alignment film refers to a film having a function of controlling the alignment of liquid crystal molecules included in the liquid crystal layer 240. On the other hand, the non-overlapping region 242 refers to a region in the liquid crystal layer 240 that does not overlap with electrode A.

[0044] The width of the electrode A can be appropriately set in consideration of the desired switching effect and viewing angle. For example, the ratio (W1 / W2) of the width W1 of the non-overlapping area 242 that does not overlap with the electrode A and the width W2 of the overlapping area 241 that overlaps with the electrode A can be 100 / 1 to 500, or 100 / 50 to 300.

[0045] The thickness D of the non-overlapping region 242 is preferably, for example, less than 100 μm. More preferably, it is less than 50 μm, further preferably less than 30 μm, particularly preferably less than 20 μm, and most preferably less than 10 μm. As such, the liquid crystal panel of this embodiment can cope with the usual liquid crystal process (generally within 10 μm), and has excellent viewing angle performance. The lower limit of the thickness is not particularly limited, for example, it is preferably greater than 1 μm.

[0046] The thickness of the non-overlapping region 242 is also referred to as the height of the non-overlapping region 242 . Figure 6 In the embodiment, the thickness of the non-overlapping region 242 corresponds to the distance D between the first electrode 231 and the interlayer insulating film 250 . Figure 6 This is a conceptual diagram for explaining the thickness D of the non-overlapping region, the width W1 of the non-overlapping region, the width W2 of the overlapping region, and the viewing angle θ.

[0047] The pitch of the non-overlapping region 242 is preferably smaller than the pixel pitch of the display panel 10. Thus, the generation of moire fringes can be fully suppressed. Among them, the pixel pitch of the display panel 10 is preferably an integer multiple of the pitch of the non-overlapping region 242. The pixel pitch is more preferably 1 to 50 times the pitch of the non-overlapping region, and further preferably 6 to 24 times.

[0048] The viewing angle θ of the liquid crystal panel 20 in the narrow viewing angle mode can be arbitrarily set by the thickness D and the width W1 of the non-overlapping region 242. Specifically, it can be set by the following formula (2): θ=2tan -1 (W1 / D)(2).

[0049] In this embodiment, a transparent electrode is used as the second electrode 232. Examples of the transparent electrode are as described above.

[0050] In this embodiment, the third electrode 233 is disposed in a planar shape on the entire surface of the second transparent substrate 220. That is, the third electrode 233 is a solid electrode that covers the second transparent substrate 220. The third electrode 233 may be a transparent electrode. Examples of the transparent electrode are as described above.

[0051] The liquid crystal layer 240 is a guest-host type liquid crystal layer (also referred to as a GH type liquid crystal layer) including a dichroic dye (guest) 2402 and liquid crystal molecules 2401 (host). The proportion of the dichroic dye 2402 is preferably 0.5 to 15% by mass relative to the total amount 100% by mass of the liquid crystal layer 240. It is more preferably 1 to 10% by mass, and further preferably 2 to 5%. The color of the dichroic dye 2402 is not particularly limited, and for example, it may be black or red, or two or more dyes of different colors may be combined to adjust to black. In addition, the dichroic dye 2402 is aligned in the same direction as the liquid crystal molecules 2401. That is, the dichroic dye 2402 can absorb light vibrating in the same direction as the liquid crystal molecules 2401.

[0052] In this embodiment, as the liquid crystal molecules (also referred to as liquid crystal components) 2401, liquid crystal molecules having a positive dielectric anisotropy (Δε) defined by the following formula (L) are used. The formula (L) is: Δε=(dielectric constant of the liquid crystal molecules in the long axis direction)-(dielectric constant of the liquid crystal molecules in the short axis direction) (L). However, it may also have a negative value (refer to the second embodiment described later). Liquid crystal molecules having positive dielectric anisotropy are oriented in a direction parallel to the direction of the electric field, and liquid crystal molecules having negative dielectric anisotropy are oriented in a direction perpendicular to the direction of the electric field. In addition, liquid crystal molecules having positive dielectric anisotropy are also referred to as positive liquid crystals (or positive liquid crystal molecules), and liquid crystal molecules having negative dielectric anisotropy are also referred to as negative liquid crystals (or negative liquid crystal molecules).

[0053] The initial alignment direction of the liquid crystal molecules 2401 is in a direction substantially perpendicular to the transmission axis of the polarizer (in this embodiment, the polarizer 141) disposed on the liquid crystal panel 20 side in a manner opposite to the liquid crystal panel 20 among the polarizers included in the display panel 10 when viewed from above. That is, the transmission axis (also referred to as the polarization transmission axis) of the polarizer 141 included in the display panel 10 is substantially perpendicular to the initial alignment direction of the liquid crystal molecules 2401 included in the liquid crystal layer 240 included in the liquid crystal panel 20 when viewed from above. Specifically, for example, the polarizer 141 has a quadrilateral plane and a thickness. When the direction of one side of the plane of the polarizer 141 is set to the x-axis direction, the direction of the other side is set to the y-axis direction, and the thickness direction is set to the z-axis direction, it is preferred that (1) the transmission axis of the polarizer 141 is in the x-axis direction and the initial orientation direction of the liquid crystal molecules 2401 is in the y-axis direction, or (2) the transmission axis of the polarizer 141 is in the y-axis direction and the initial orientation direction of the liquid crystal molecules 2401 is in the x-axis direction.

[0054] In this specification, regarding the configuration angle between the initial orientation direction of the liquid crystal molecules and the transmission axis direction of the polarizer, "substantially perpendicular (also referred to as substantially orthogonal)" and "substantially perpendicular configuration (also referred to as substantially orthogonal configuration)" mean forming an angle (absolute value) within the range of 90±10°. The angle is preferably within the range of 90±5°, more preferably within the range of 90±3°, further preferably within the range of 90±1°, and particularly preferably 90° (completely perpendicular).

[0055] In this embodiment, Figure 2AThe right side of the diagram also shows the orientation of the liquid crystal molecules 2401 and the dichroic dye 2402 in the liquid crystal layer 240 when no voltage is applied (wide viewing angle mode), and the transmission axis direction (indicated by arrows) of the polarizer 141 of the display panel 10 (front view). Figure 2C The (i) column of FIG. 1 shows a diagram (top view) showing the orientation of the liquid crystal molecules 2401 in the liquid crystal layer 240 when no voltage is applied, as viewed from directly above (observation side). Figure 2C The column (ii) of FIG. 1 shows a view (top view) of the transmission axis direction of the polarizing plate 141 included in the display panel 10 as viewed from the observation surface side. Figure 2C It can be seen that the initial alignment direction of the liquid crystal molecules 2401 (vertical direction in the drawing) and the transmission axis direction of the polarizing plate 141 (horizontal direction in the drawing) are substantially perpendicular to each other when viewed from above.

[0056] Here, the inventors of the present application have found the following problem: as described above, in the image display device 1R, the grille function may not be fully obtained depending on the polarization direction of the incident light. In addition, it has been found that the reason is that among the light incident on the liquid crystal layer 240 (GH-type liquid crystal layer), the light that is orthogonal to the orientation direction of the liquid crystal molecules in the liquid crystal layer is not absorbed but transmitted (see also Fig. 27 , Fig.28A and Fig.28B ). Therefore, as mentioned above, the inventors of the present application solved the above-mentioned problem by setting the initial orientation direction of the liquid crystal molecules 2401 and the transmission axis direction of the polarizer 141 to be approximately perpendicular when viewed from above. By setting it to such a configuration, the liquid crystal layer 240 itself can effectively function as a grid that can be switched on / off. In this way, the image display device of the present invention has a grid function in addition to the function of controlling the viewing angle by applying or not applying a voltage. Therefore, compared with an image display device having a grid layer separately from a liquid crystal panel, the thickness, weight and manufacturing cost of the liquid crystal panel and the image display device having the liquid crystal panel can be suppressed. In addition, in order to further improve the grid function, the liquid crystal molecules 2401 are preferably more ordered. For example, it is preferred to have physical properties such as a high transition temperature Tni of the liquid crystal molecules 2401 and a small scattering parameter.

[0057] As described above, the liquid crystal layer 240 has an overlapping region 241 overlapping with the second electrode 232, and a non-overlapping region 242 not overlapping with the second electrode 232. The liquid crystal layer 240 is a GH-type liquid crystal layer including liquid crystal molecules having a predetermined initial alignment direction, and has the characteristics of having the overlapping region 241 and the non-overlapping region 242, whereby the liquid crystal layer 240 has a transparent region and a switching region that switches between a transmission state and an absorption state.

[0058] In this embodiment, the switching region is designed to switch between the transmission state and the absorption state by applying or not applying the voltage between the first electrode 231 and the second electrode 232 (262). Figure 4A c) in the figure becomes the switching area, and the portion of the boundary portion c (equivalent to Figure 4A a), and the portion where the boundary portion c is removed from the non-overlapping region 242 (equivalent to Figure 4A b) in the figure becomes a transparent area. In addition, the voltage applying unit only needs to be a power source that can be turned on / off.

[0059] The boundary portion between the overlapping area 241 and the non-overlapping area 242 that becomes the switching area includes not only the strict boundary between the overlapping area 241 and the non-overlapping area 242, but also the overlapping area 241 and the non-overlapping area 242 located around the boundary. That is, the switching area includes a part of the overlapping area 241 and the non-overlapping area 242 (see a to c in FIG. 4 ).

[0060] Here, the important point in the present invention is that the liquid crystal layer 240 is a GH-type liquid crystal layer containing liquid crystal molecules having a predetermined initial orientation direction, and by having an overlapping area 241 overlapping with the electrode A (the second electrode 232 in the present embodiment), and a non-overlapping area 242 that does not overlap with the electrode A, the liquid crystal layer 240 has a transparent area and a switching area that switches between a transmission state and an absorption state. That is, an important feature of the present invention is that by applying a voltage to each electrode, a transparent area with high transmittance and an absorption area with low transmittance are formed in the liquid crystal layer 240, so that the liquid crystal layer 240 itself can function as a grid that can be switched on / off. Therefore, as long as a transparent area with high transmittance and an absorption area with low transmittance are formed when a voltage is applied, the degree of overlap between the switching area and the overlapping area 241 or the non-overlapping area 242 is not particularly limited. In addition, the transparent area and the switching area are not limited to Figure 4A The described method can be appropriately controlled according to, for example, the width and pitch of the electrodes A, the cell thickness (ie, the thickness D of the non-overlapping region 242 ), the voltage applied to each electrode, and the like.

[0061] In this embodiment, the second electrode 232 and the third electrode 233 are arranged with the interlayer insulating film 250 interposed therebetween. In this case, the first electrode 231 functions as a common electrode, and the second voltage applying unit 261 between the first electrode 231 and the third electrode 233 can control whether the voltage is applied to the non-overlapping region 242, and the first voltage applying unit 262 between the first electrode 231 and the second electrode 232 can control whether the voltage is applied to the overlapping region 241. Such an electrode structure can cope with various driving methods in the field of image display devices, and is therefore very useful.

[0062] The transparent region refers to a region that shows a transmission state in both cases when a voltage is applied and when a voltage is not applied. The transmission state refers to a state that is transparent to light. On the other hand, the switching region refers to a region that switches between a transmission state and an absorption state. The absorption state refers to a state in which light is absorbed, and the transmittance is lower than that of the transmission state. The liquid crystal layer 240 in the absorption state is in the same state as the light shielding glass.

[0063] In this embodiment, as described later, in the wide viewing angle mode (see Figure 3A and Figure 3B ), the liquid crystal layer 240 has a certain transmittance (also called visible light transmittance or light transmittance) T1. On the other hand, in the narrow viewing angle mode (refer to Figure 4A and Figure 4B )Down, Figure 4A The transparent areas a and b in the graph have transmittances T2 and T3 respectively. Figure 4A The switching region c in the embodiment has a transmittance T4 due to absorption. Among them, T1, T2, T3 and T4 satisfy the relationship of "T1 ≥ T2 > T4" and "T1 ≥ T3 > T4". The magnitude relationship between T2 and T3 is not limited. The transmittance T1 may be 100%, and T4 may be 0%.

[0064] Figure 3B This is used for the wide viewing angle mode ( Figure 3A ) is a diagram for explaining the orientation direction (initial orientation direction) of the liquid crystal molecules 2401 under the condition of Figure 3A Figure XX' portion of the liquid crystal layer 240 (top view). Figure 3B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Figure 4B and Figure 4C This is used for the narrow viewing angle mode ( Figure 4A ) is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 under. Specifically, Figure 4B Observe from the side Figure 4AFigure XX' portion of the liquid crystal layer 240 (top view). Figure 4B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Figure 4C is from Figure 4A Only the liquid crystal panel 20 is selected and the orientation of the liquid crystal molecules 2401 is studied (cross-sectional view). Figure 4C The dashed lines in the figure represent electric power lines.

[0065] like Figure 3A and Figure 4A As shown, light enters the liquid crystal panel 20 from the back side (specifically, the backlight source 40) via the display panel 10. In a state where no voltage is applied between the first electrode 231 and the second electrode 232 (262), and no voltage is applied between the first electrode 231 and the third electrode 233 (261) (voltage non-applied state), the polarization direction of the light incident on the liquid crystal layer 240 and the orientation direction of the liquid crystal molecules 2401 in the liquid crystal layer 240 are substantially orthogonal (also referred to as substantially vertical) when viewed from above (see FIG. 1 ). Figure 3B ), so the incident light is not absorbed in the liquid crystal layer 240. That is, the liquid crystal layer 240 is integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent region) (refer to Figure 3A In this case, light from all directions of the backlight source 40 passes through the liquid crystal panel 20 (see Figure 3A ). As a result, light from the back side can be transmitted from the lower polar angle side to the higher polar angle side without loss, so a wide viewing angle mode can be achieved with high brightness.

[0066] On the other hand, in a state (voltage applied state) where a voltage is applied between the first electrode 231 and the second electrode 232 (262) and no voltage is applied between the first electrode 231 and the third electrode 233 (261), the liquid crystal layer 240 itself functions as a grid. That is, among the light incident on the liquid crystal layer 240 from the backlight source 40, the oblique light 1LB and a part of the front light 1LA are reflected at the boundary portion ( Figure 4A The light is absorbed (attenuated) in the c region in FIG. 1 and passes through the liquid crystal panel 20 (refer to FIG. 1 ). Figure 4A Specifically, in the area mainly corresponding to the overlapping area 241 ( Figure 4A In the region a in FIG. 1 , a longitudinal electric field is generated between the first electrode 231 and the second electrode 232, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizing plate 141 of the display panel 10 (front view) (see FIG. Figure 4CTherefore, the incident light is transmitted without being absorbed. In the area mainly corresponding to the non-overlapping area 242 ( Figure 4A In the region b in FIG. 1 , no voltage is applied, that is, the first electrode 231 and the third electrode 233 have the same potential, so the liquid crystal molecules 2401 maintain an orientation substantially horizontal to the transmission axis of the polarizer 141 of the display panel 10 (front view) (see FIG. Figure 4C In contrast, at the boundary portion ( b area) between the overlapping area 241 and the non-overlapping area 242, the incident light is transmitted without being absorbed. Figure 4A In the c region in FIG. 1 , a lateral electric field is generated between the second electrode 232 and the third electrode 233, and the orientation direction of the liquid crystal molecules 2401 changes by approximately 90° when viewed from above (see FIG. 1 ). Figure 4C c region). Therefore, the liquid crystal molecules 2401 are arranged along the electric field direction. In this case, the polarization direction of the light incident through the polarizing plate 141 of the display panel 10 is consistent with the orientation direction of the liquid crystal molecules 2401, so the incident light is absorbed.

[0067] By switching the voltage in this way, it is possible to form an absorption state region (switching region) and a transmission state region (transparent region). Figure 4A The a and b regions in the image remain in the same transmission state, while Figure 4A The c region in the absorbing state becomes Figure 4A The transparent areas a and b in the graph have transmittances T2 and T3 respectively. Figure 4A The switching region c in the liquid crystal panel 20 has a state of transmittance T4 by absorption (where T1 ≥ T2 > T4 and T1 ≥ T3 > T4). In addition, the front light 1LA of the light incident on the liquid crystal panel 20 from the backlight source 40 passes through the liquid crystal panel 20 without attenuation (see Figure 4A As a result, the light from the backlight source 40 is attenuated on the higher polar angle side, and the light from the back side can be transmitted only on the lower polar angle side with the original brightness, so that a narrow viewing angle mode can be achieved.

[0068] In this specification, regarding the change angle between the initial orientation direction of the liquid crystal molecules and the orientation direction of the liquid crystal molecules when a voltage is applied, "approximately 90°" means an angle (absolute value) within the range of 90±10°. The angle is preferably within the range of 90±5°, more preferably within the range of 90±3°, further preferably within the range of 90±1°, and particularly preferably 90° (completely vertical).

[0069] As the interlayer insulating film 250, any one of an organic insulating film, an inorganic insulating film, or a stack of an organic insulating film and an inorganic insulating film can be used. As the organic insulating film, for example, organic films such as acrylic resin, polyimide resin, and novolac resin (relative dielectric constant ε=2 to 5), and stacks thereof can be used. The film thickness of the organic insulating film is not particularly limited, and for example, it is greater than 2 μm and less than 4 μm. As the inorganic insulating film, for example, inorganic films such as silicon nitride (SiNx) and silicon oxide (SiO2) (relative dielectric constant ε=5 to 7), and stacks thereof can be used. The film thickness of the inorganic insulating film is not particularly limited, and for example, it is Above and the following.

[0070] The film thickness of the interlayer insulating film 250 is preferably not less than 0.1 μm and not more than 4 μm, and more preferably not less than 0.15 μm and not more than 0.35 μm.

[0071] As described above, the liquid crystal panel 20 can cope with the usual liquid crystal process (generally within 10 μm), so it can easily achieve a narrow viewing angle mode, and the viewing angle performance is excellent. In addition, in this embodiment, the transparent area and the switching area are distinguished by the design of the power supply (such as the configuration of the electrodes, etc.), rather than being physically distinguished by the material. The transparent area and the switching area are formed of the same material. Therefore, in this embodiment, there is no need for, for example, the Fig.11 The UV curing step for fixing the liquid crystal panel 20 in advance to the transmission state (transparent region) during manufacturing as shown in the figure is advantageous in that the manufacturing process of the liquid crystal panel and the image display device can be simplified.

[0072] The liquid crystal panel 20 may not have a polarizing plate. That is, the display panel 10 has a polarizing plate (in this embodiment, the polarizing plate 141) on the liquid crystal panel 20 side, and the polarizing plate can also be used as a polarizing plate of the liquid crystal panel 20. Therefore, there is no need to add a polarizing plate to the liquid crystal panel 20, and the transmission loss can be further suppressed.

[0073] <Display Panel> The display panel 10 only needs to have a function of displaying an image. The display panel 10 can turn on / off the image display. In this embodiment, the case where the display panel 10 is a liquid crystal display panel is described as an example.

[0074] like Figure 1As shown, the display panel 10 includes, from the observation side toward the back side, a polarizing plate 141, a CF substrate 110 including a color filter (CF) layer, a liquid crystal layer 130, a TFT substrate 120 including a thin film transistor (TFT), and a polarizing plate 142. In this embodiment, the display panel 10 functions as a liquid crystal display panel, and thus the image display device of this embodiment is a liquid crystal display device.

[0075] Among the polarizers possessed by the display panel 10, the polarizer (in the present embodiment, the polarizer 141) arranged on the liquid crystal panel 20 side in a manner opposite to the liquid crystal panel 20 is arranged so that its transmission axis is approximately perpendicular to the initial orientation direction of the liquid crystal molecules 2401 contained in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above.

[0076] The polarizing plates 141 and 142 may be arranged so that their transmission axes are parallel to each other or orthogonal to each other, that is, the polarizing plates 141 and 142 may be arranged in a parallel Nicol arrangement or in an orthogonal Nicol arrangement.

[0077] Here, "parallel to each other" means that the transmission axes form an angle within the range of 0°±10° with each other. The angle is preferably within the range of 0°±5°. "Orthogonal" means forming an angle within the range of 90°±10°. The angle is preferably within the range of 90°±5°.

[0078] The axial orientation of the polarizing plates 141 and 142 can be appropriately set, for example, preferably set within the range of 0°±10° or 90°±10°. Among them, it is more preferably set within the range of 0°±5° or 90°±5°, and further preferably substantially set to 0° or 90°. Thus, a bright display can be obtained in the normal direction and the up, down, left, and right directions.

[0079] Polarizers 141 and 142 are linear polarizers. A linear polarizer is a polarizer that has the function of extracting polarized light (linear polarized light) that vibrates only in a specific direction from unpolarized light (natural light), partially polarized light, or polarized light. The polarizer (polarizer 142 in this embodiment) disposed on the backlight source 40 side is a polarizer corresponding to the wavelength of light from the backlight source 40. The light from the backlight source 40 is incident on the polarizer 142, and only the linear polarized light vibrating along the polarization transmission axis of the polarizer 142 is transmitted.

[0080] The polarizers 141 and 142 may be absorptive polarizers or reflective polarizers. Both may be absorptive polarizers, or one may be a reflective polarizer and the other may be absorptive polarizer.

[0081] As an absorption type polarizer, specifically, for example, a polarizer obtained by dyeing a polyvinyl alcohol film and adsorbing an anisotropic material such as an iodine complex (or dye) and then stretching and aligning it can be cited. Generally speaking, in order to ensure mechanical strength and moisture and heat resistance, a protective film such as a triacetyl cellulose film is laminated on both sides of the polyvinyl alcohol film for practical use. In addition, as a reflection type polarizer, specifically, for example, a film laminated with multiple dielectric films, a film laminated with multiple films with different refractive index anisotropy, a nanowire grid polarizer, a polarizer using selective reflection of cholesteric liquid crystal, etc. can be cited.

[0082] As the CF substrate 110, a CF substrate commonly used in the field of liquid crystal display panels can be used, for example, a structure in which components such as color filters and black matrix (BM: Black Matrix) layers are arranged on the surface of a transparent substrate such as a glass substrate. More specifically, the CF substrate 110 includes: a black matrix arranged in a grid pattern on an insulating substrate in a manner corresponding to gate lines and source lines; a plurality of color filters including a red layer, a green layer, and a blue layer arranged in a periodic manner between the grids of the black matrix; an outer coating layer composed of a transparent insulating resin arranged in a manner covering the black matrix and each color filter; and a photo spacer arranged in a columnar shape on the outer coating layer.

[0083] The TFT substrate 120 has an insulating substrate, and in the display area, a plurality of gate lines extending in parallel to each other and a plurality of source lines extending in parallel to each other in a direction intersecting the gate lines via an insulating film are provided on the insulating substrate. The plurality of gate lines and the plurality of source lines are formed in a lattice shape as a whole in a manner of dividing each pixel. A thin film transistor as a switching element is arranged at the intersection of each source line and each gate line.

[0084] The TFT substrate 120 has: a planar common electrode, which is arranged on the surface of the liquid crystal layer 130 side of the insulating substrate; an insulating film, which covers the common electrode; and a pixel electrode, which is arranged on the surface of the liquid crystal layer side of the insulating film and is provided with a slit. The pixel electrode is arranged in each area surrounded by two adjacent source lines and two adjacent gate lines, and the pixel electrode is electrically connected to the corresponding source line via the semiconductor layer possessed by the thin film transistor. That is, the display panel 10 of this embodiment is a liquid crystal display panel in FFS (Fringe Field Switching) mode. The configuration of the common electrode and the pixel electrode can also be interchangeable. In this case, a common electrode provided with a slit is arranged on the planar pixel electrode formed in a manner occupying each pixel area through an insulating film.

[0085] In the present embodiment, a display panel 10 of a horizontal alignment mode in which pixel electrodes and a common electrode are arranged on one side of a substrate is used. The horizontal alignment mode refers to a mode in which liquid crystal molecules are aligned in a direction substantially horizontal to the respective main surfaces of a pair of substrates when no voltage is applied to the liquid crystal layer. In addition to the above-mentioned FFS mode, for example, an IPS (In-Plane Switching) mode can be cited. The display panel 10 can also be a vertical alignment mode in which the pixel electrodes are arranged on the TFT substrate 120 and the common electrodes are arranged on the CF substrate 110. The vertical alignment mode refers to a mode in which liquid crystal molecules are aligned in a direction substantially vertical to the respective main surfaces of a pair of substrates when no voltage is applied to the liquid crystal layer. For example, a VA (Vertical Alignment) mode, a TN (Twisted Nematic) mode, etc. can be cited.

[0086] An orientation film having the function of controlling the orientation of liquid crystal molecules contained in the liquid crystal layer 130 is respectively arranged between the TFT substrate 120 and the liquid crystal layer 130, and between the CF substrate 110 and the liquid crystal layer 130. When no voltage is applied between the pixel electrode and the common electrode, the liquid crystal molecules contained in the liquid crystal layer 130 are oriented approximately horizontally relative to the main surfaces of each of the pair of substrates.

[0087] The display panel 10 also includes a source driver electrically connected to the source line, a gate driver electrically connected to the gate line, and a controller. The gate driver sequentially supplies scanning signals to the gate lines based on the control of the controller. The source driver supplies data signals to the source lines based on the control of the controller when the TFT is in a voltage-applied state through the scanning signal. The pixel electrodes are respectively set to potentials corresponding to the data signals supplied via the corresponding TFTs, and a fringe electric field is generated between the pixel electrodes and the common electrode, causing the liquid crystal molecules of the liquid crystal layer to rotate. By controlling the magnitude of the voltage applied between the pixel electrode and the common electrode in this way, the delay of the liquid crystal layer changes, thereby controlling the transmission or non-transmission of light.

[0088] The adhesive layer 150 (OCA, etc.) is not particularly limited, and any adhesive layer used in a normal liquid crystal display device can be used. The liquid crystal layer 130 can also be any liquid crystal layer commonly used in a normal liquid crystal display device, and thus description thereof is omitted.

[0089] <Backlight> The backlight source 40 is not particularly limited as long as it can irradiate light to the liquid crystal panel 20 and / or the display panel 10. For example, the backlight source 40 may have a light source and a reflector. As the light source, a common backlight source, such as a cold cathode fluorescent lamp (CCFL) or a light emitting diode (LED), may be used.

[0090] The backlight source 40 can be a direct-down type or an edge-light type. Taking the edge-light type as an example, the backlight source 40 has a structure including a light source, a reflective sheet, and a light guide plate. The light source is arranged on the end surface of the light guide plate, and the reflective sheet is arranged on the back surface of the light guide plate. The light guide plate can use a light guide plate commonly used in the field of image display devices. As the reflective sheet, for example, an aluminum plate, a white polyethylene terephthalate (PET) film, a reflective film (for example, ESR (Enhanced Specular Reflector) film manufactured by 3M Company), etc. can be cited.

[0091] As the backlight source 40, in addition, a backlight source driven by local dimming can also be used. Local dimming drive refers to a function of dividing the image display area of ​​the display device into multiple areas (also called segments) and controlling the light according to each area. If a backlight source driven by local dimming is used, the brightness of the backlight source can be locally controlled, so that high contrast and low power consumption of the display device can be achieved. However, generally, in a display device in which the viewing angle is controlled by the backlight source, it is difficult to take into account both the control of the viewing angle and the local dimming drive. In contrast, in the present invention, the viewing angle can be controlled by the liquid crystal panel 20, so the driving method of the backlight source is not selected. Therefore, it is very useful to be able to combine the liquid crystal panel 20 with the backlight source driven by local dimming.

[0092] <Other structures> The image display device of this embodiment is composed of multiple components, in addition to the above-mentioned components, such as TCP (tape carrier package), PCB (printed wiring board) and other external circuits, optical films such as viewing angle expansion film and brightness enhancement film, frame (frame), etc., and can be assembled to other components depending on the components. There is no special limitation on components other than those already described, and components commonly used in the field of image display devices can be used, so the description is omitted.

[0093] (Second Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents repeated in the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the liquid crystal molecules 2401 included in the liquid crystal layer 240 of the liquid crystal panel 20 are liquid crystal molecules having a negative dielectric anisotropy (Δε).

[0094] Fig. 7A It is a schematic cross-sectional view of the image display device of this embodiment. Fig. 8A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the present embodiment. Fig.9A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the present embodiment.

[0095] In this embodiment, Fig. 7A The right side of the diagram also shows the orientation of the liquid crystal molecules 2401 and the dichroic dye 2402 in the liquid crystal layer 240 when no voltage is applied, and the transmission axis direction (indicated by arrows) of the polarizer 141 of the display panel 10 (front view). Figure 7B The (i) column of FIG. 1 shows a diagram (top view) showing the orientation of the liquid crystal molecules 2401 in the liquid crystal layer 240 when no voltage is applied, as viewed from the observation surface side. Figure 7B The column (ii) of FIG. 1 shows a view (top view) of the transmission axis direction of the polarizing plate 141 included in the display panel 10 as viewed from the observation surface side. Figure 7B It can be seen that the initial alignment direction of the liquid crystal molecules 2401 (left-right direction in the drawing) and the transmission axis direction of the polarizing plate 141 (up-down direction in the drawing) are approximately perpendicular to each other when viewed from above.

[0096] Figure 8B This is used for the wide viewing angle mode ( Fig. 8A ) is a diagram for explaining the orientation direction (initial orientation direction) of the liquid crystal molecules 2401 under the condition of Fig. 8A Figure XX' portion of the liquid crystal layer 240 (top view). Figure 8B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Fig. 9B This is used for the narrow viewing angle mode ( Fig.9A ) is a diagram illustrating the orientation direction of the liquid crystal molecules 2401 under the condition of Fig.9A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 9B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above).

[0097] In this embodiment, as described later, in the wide viewing angle mode (see Fig. 8A and Figure 8B ), the liquid crystal layer 240 has a certain transmittance T1. On the other hand, in the narrow viewing angle mode (refer to Fig.9A and Fig. 9B )Down, Fig.9A The transparent areas a and b in the graph have transmittances T2 and T3 respectively. Fig.9A The switching region c in the embodiment has a transmittance T4 due to absorption. Among them, T1, T2, T3 and T4 satisfy the relationship of "T1 ≥ T2 > T4" and "T1 ≥ T3 > T4". The magnitude relationship between T2 and T3 is not limited. The transmittance T1 may be 100%, and T4 may be 0%.

[0098] like Fig. 8A and Fig.9A As shown, light enters the liquid crystal panel 20 from the back side (specifically, the backlight source 40) via the display panel 10. In a state where no voltage is applied between the first electrode 231 and the second electrode 232 (262), and no voltage is applied between the first electrode 231 and the third electrode 233 (261) (voltage-unapplied state), the polarization direction of light incident on the liquid crystal layer 240 and the orientation direction of the liquid crystal molecules 2401 in the liquid crystal layer 240 are substantially orthogonal when viewed from above (refer to FIG. 1 ). Figure 8B ), so the incident light is not absorbed in the liquid crystal layer 240. That is, the liquid crystal layer 240 is integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent region) (refer to Fig. 8A In this case, light from all directions of the backlight source 40 passes through the liquid crystal panel 20 (see Fig. 8A ). As a result, light from the back side can be transmitted from the lower polar angle side to the higher polar angle side without loss, so a wide viewing angle mode can be achieved with high brightness.

[0099] On the other hand, in a state (voltage applied state) where a voltage is applied between the first electrode 231 and the second electrode 232 (262) and no voltage is applied between the first electrode 231 and the third electrode 233 (261), the liquid crystal layer 240 itself functions as a grid. That is, among the light incident on the liquid crystal layer 240 from the backlight source 40, the oblique light 1LB and a part of the front light 1LA are reflected at the boundary portion ( Fig.9A The light is absorbed (attenuated) in the c region in FIG. 1 and passes through the liquid crystal panel 20 (refer to FIG. 1 ). Fig.9A Specifically, in the area mainly corresponding to the overlapping area 241 ( Fig.9A In the region a in the figure, a longitudinal electric field is generated between the first electrode 231 and the second electrode 232, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. In the region ( Fig.9A In the region b in the figure, no voltage is applied, that is, the first electrode 231 and the third electrode 233 have the same potential, so the liquid crystal molecules 2401 maintain an orientation substantially horizontal to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. In contrast, at the boundary portion ( Fig.9AIn the c region in the display panel 10, a lateral electric field is generated between the second electrode 232 and the third electrode 233, and the orientation direction of the liquid crystal molecules 2401 changes by approximately 90° when viewed from above. Therefore, the liquid crystal molecules 2401 are arranged along the electric field direction. In this case, the polarization direction of the light incident through the polarizer 141 of the display panel 10 is consistent with the orientation direction of the liquid crystal molecules 2401, so the incident light is absorbed.

[0100] By switching the voltage in this way, it is possible to form an absorption state region (switching region) and a transmission state region (transparent region). Fig.9A The a and b regions in the image remain in the same transmission state, while Fig.9A The c region in the absorbing state becomes Fig.9A The transparent areas a and b in the graph have transmittances T2 and T3 respectively. Fig.9A The switching region c in the liquid crystal panel 20 has a state of transmittance T4 by absorption (where T1 ≥ T2 > T4 and T1 ≥ T3 > T4). In addition, the front light 1LA of the light incident on the liquid crystal panel 20 from the backlight source 40 passes through the liquid crystal panel 20 without attenuation (see Fig.9A As a result, the light from the backlight source 40 is attenuated on the higher polar angle side, and the light from the back side can be transmitted only on the lower polar angle side with the original brightness, so that a narrow viewing angle mode can be achieved.

[0101] (Third Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the arrangement of the liquid crystal panel 20 and the display panel 10 is different.

[0102] In the image display device 1 of the first embodiment, the display panel 10 is arranged on the back side of the liquid crystal panel 20, but the display panel 10 may be arranged on the viewing side of the liquid crystal panel 20. Fig.10 As shown, the image display device 1 may be configured to include a display panel 10 , a liquid crystal panel 20 , and a backlight 40 in this order from the observation surface side toward the back surface side. Fig.10 It is a schematic cross-sectional view of the image display device of this embodiment.

[0103] In this embodiment, among the polarizers possessed by the display panel 10, the polarizer (in this embodiment, the polarizer 142) that is arranged on the side of the liquid crystal panel 20 in a manner opposite to the liquid crystal panel 20 has a transmission axis that is approximately perpendicular to the initial orientation direction of the liquid crystal molecules 2401 contained in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above.

[0104] In this embodiment, Fig.10The right side of the (sectional schematic diagram) also shows the orientation of the liquid crystal molecules 2401 and the dichroic dye 2402 in the liquid crystal layer 240 when no voltage is applied, and the transmission axis direction (indicated by arrows) of the polarizer 142 of the display panel 10 (front view). Figure 2C The (i) column of FIG. 1 shows a diagram (top view) showing the orientation of the liquid crystal molecules 2401 in the liquid crystal layer 240 when no voltage is applied, as viewed from the observation surface side. Figure 2C The column (ii) of FIG. 1 shows a view (top view) of the transmission axis direction of the polarizing plate 142 included in the display panel 10 as viewed from the observation surface side. Figure 2C It can be seen that the initial alignment direction of the liquid crystal molecules 2401 (vertical direction in the drawing) and the transmission axis direction of the polarizing plate 142 (horizontal direction in the drawing) are approximately perpendicular to each other when viewed from above.

[0105] In this embodiment, light is incident on the liquid crystal panel 20 from the back side (specifically, the backlight 40), and only the light that has passed through the liquid crystal panel 20 is incident on the display panel 10. In this case, the wide viewing angle mode and the narrow viewing angle mode can be realized respectively based on substantially the same principle as in the first embodiment.

[0106] (Fourth Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the layer structure (layer arrangement) of the liquid crystal panel 20 is different.

[0107] Fig.11 2 is a cross-sectional schematic diagram of the image display device of this embodiment. In the first embodiment, the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, an interlayer insulating film 250, a third electrode 233 and a second transparent substrate 220 in order from the observation side to the back side (see Figure 1 In this embodiment, the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, an interlayer insulating film 250, a third electrode 233 and a second transparent substrate 220 in order from the back side to the observation side (see Fig.11 In other words, the liquid crystal panel 20 of the present embodiment includes the second transparent substrate 220, the third electrode 233, the interlayer insulating film 250, the second electrode 232, the liquid crystal layer 240, the first electrode 231 and the first transparent substrate 210 in order from the observation side toward the back side.

[0108] The second electrode 232 is configured to be striped in a plan view, and the second electrode 232 is arranged opposite to the first electrode 231 via the liquid crystal layer 240. The liquid crystal panel 20 further includes a first voltage applying unit 262 for applying a voltage between the first electrode 231 and the second electrode 232, and a second voltage applying unit 261 (not shown) for applying a voltage between the first electrode 231 and the third electrode 233. The polarizing plate 141 included in the display panel 10 is arranged opposite to the display panel 10 side (the back side in this embodiment) of the liquid crystal panel 20.

[0109] In this embodiment, among the polarizers possessed by the display panel 10, the polarizer (in this embodiment, the polarizer 141) configured on the liquid crystal panel 20 side in a manner opposite to the liquid crystal panel 20 has a transmission axis that is approximately perpendicular to the initial orientation direction of the liquid crystal molecules 2401 contained in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above.

[0110] In this embodiment, Fig.11 The right side of the (sectional schematic diagram) also shows the orientation of the liquid crystal molecules 2401 and the dichroic dye 2402 in the liquid crystal layer 240 when no voltage is applied, and the transmission axis direction (indicated by arrows) of the polarizer 142 of the display panel 10 (front view).

[0111] (Variation of the Fourth Embodiment) In the fourth embodiment, the display panel 10 is arranged on the back side of the liquid crystal panel 20, but the display panel 10 may be arranged on the viewing side of the liquid crystal panel 20. That is, the image display device 1 may include the display panel 10, the liquid crystal panel 20 and the backlight source 40 in order from the viewing side toward the back side, and the liquid crystal panel 20 may include the second transparent substrate 220, the third electrode 233, the interlayer insulating film 250, the second electrode 232, the liquid crystal layer 240, the first electrode 231 and the first transparent substrate 210 in order from the viewing side toward the back side (see Fig.12 In this case, the transmission axis of the polarizer (in the present embodiment, the polarizer 142) disposed on the liquid crystal panel 20 side in a manner opposite to the liquid crystal panel 20 among the polarizers included in the display panel 10 is also substantially perpendicular to the initial orientation direction of the liquid crystal molecules 2401 included in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above. Fig.12 It is a schematic cross-sectional view of the image display device of this example.

[0112] (Fifth Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the electrode structure of the liquid crystal panel 20 is different.

[0113] Fig.13 It is a schematic cross-sectional view of the image display device of this embodiment. Fig.14A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the present embodiment. Fig.15A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the present embodiment.

[0114] In this embodiment, if Fig.13 As shown in the figure, the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 231, a first interlayer insulating film 251, a second electrode 2321, a liquid crystal layer 240, a third electrode 2322, a second interlayer insulating film 252, a fourth electrode 233 and a second transparent substrate 220 in order from the observation side to the back side. The liquid crystal panel 20 also includes a second voltage applying unit 263 for applying a voltage between the first electrode 231 and the fourth electrode 233, and a first voltage applying unit 264 for applying a voltage between the second electrode 2321 and the third electrode 2322. In addition, the polarizing plate 141 included in the display panel 10 is arranged opposite to the display panel 10 side (the back side in this embodiment) of the liquid crystal panel 20.

[0115] The first electrode 231 is disposed in a planar shape on the entire surface of the first transparent substrate 210. That is, the first electrode 231 is a solid electrode that covers the first transparent substrate 210. In addition, the fourth electrode 233 is disposed in a planar shape on the entire surface of the second transparent substrate 220. That is, the fourth electrode 233 is a solid electrode that covers the second transparent substrate 220. The first electrode 231 and the fourth electrode 233 may be transparent electrodes. Examples of the transparent electrodes are as described above.

[0116] The second electrode 2321 is configured to be striped when viewed from above. The third electrode 2322 is also configured to be striped when viewed from above. The second electrode 2321 and the third electrode 2322 are configured to be substantially opposite to each other. In this embodiment, both the second electrode 2321 and the third electrode 2322 are equivalent to the electrode A. Therefore, in this embodiment, the second electrode 2321 is equivalent to the electrode A and the third electrode 2322 is equivalent to the electrode B, and the third electrode 2322 is equivalent to the electrode A and the second electrode 2321 is equivalent to the electrode B. The second electrode 2321 and the third electrode 2322 may be transparent electrodes. Examples of transparent electrodes are as described above.

[0117] By configuring the electrode A (the second electrode 2321 and the third electrode 2322 in the present embodiment) to be striped when viewed from above, and configuring the second electrode 2321 and the third electrode 2322 to be approximately opposite, the liquid crystal layer 240 has an overlapping area 241 that overlaps with the second electrode 2321 and the third electrode 2322, and a non-overlapping area 242 that does not overlap with either the second electrode 2321 or the third electrode 2322.

[0118] In this embodiment, the switching region is designed to switch between the transmission state and the absorption state according to whether the voltage between the second electrode 2321 and the third electrode 2322 (264) is applied or not applied, and whether the voltage between the first electrode 231 and the fourth electrode 233 (263) is applied or not applied. Fig.15A c) in the figure becomes the switching area, and the portion of the boundary portion c (equivalent to Fig.15A a), and the portion where the boundary portion c is removed from the non-overlapping region 242 (equivalent to Fig.15A The a' in the figure becomes a transparent area. In addition, the voltage applying unit only needs to be a power source that can be turned on / off.

[0119] In this embodiment, as described later, in the wide viewing angle mode (see Fig.14A and Fig. 14B ), the liquid crystal layer 240 has a certain transmittance T1. On the other hand, in the narrow viewing angle mode (refer to Fig.15A and Fig. 15B )Down, Fig.15A The transparent areas a and a' in the graph have transmittances T2 and T3, respectively. Fig.15A The switching region c in the embodiment has a transmittance T4 due to absorption. Among them, T1, T2, T3 and T4 satisfy the relationship of "T1 ≥ T2 > T4" and "T1 ≥ T3 > T4". The magnitude relationship between T2 and T3 is not limited. The transmittance T1 may be 100%, and T4 may be 0%.

[0120] Fig. 14B This is used for the wide viewing angle mode ( Fig.14A ) is a diagram for explaining the orientation direction (initial orientation direction) of the liquid crystal molecules 2401 under the condition of Fig.14A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 14B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Fig. 15B This is used for the narrow viewing angle mode ( Fig.15A) is a diagram illustrating the orientation direction of the liquid crystal molecules 2401 under the condition of Fig.15A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 15B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above).

[0121] like Fig.14A and Fig.15A As shown, light enters the liquid crystal panel 20 from the back side (specifically, the backlight source 40) via the display panel 10. Here, in a state where regions with different orientations of liquid crystal molecules 2401 are found in the liquid crystal layer 240 when viewed from above (i.e., regions with different electric fields in the liquid crystal layer 240), the liquid crystal layer 240 itself functions as a grid. That is, among the light incident from the backlight source 40 to the liquid crystal layer 240, the light 1LB in the oblique direction and the light 1LA in the front direction are partially reflected at the boundary portion ( Fig.15A The light is absorbed (attenuated) in the c region in FIG. 1 and passes through the liquid crystal panel 20 (refer to FIG. 2 ). Fig.15A Specifically, in the area mainly corresponding to the overlapping area 241 ( Fig.15A In the region a in the figure, a longitudinal electric field is generated between the second electrode 2321 and the third electrode 2322, and the liquid crystal molecules 2401 are oriented in a direction substantially perpendicular to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. In the region ( Fig.15A In the a' region in the figure), a longitudinal electric field is generated between the first electrode 231 and the fourth electrode 233, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. In contrast, at the boundary portion ( Fig.15A In the c region in the display panel 10, a lateral electric field is generated between the first electrode 231 and the second electrode 2321, and between the third electrode 2322 and the fourth electrode 233, and the orientation direction of the liquid crystal molecules 2401 changes by approximately 90° when viewed from above. Therefore, the liquid crystal molecules 2401 are arranged along the electric field direction. In this case, the polarization direction of the light incident through the polarizer 141 of the display panel 10 is consistent with the orientation direction of the liquid crystal molecules 2401, so the incident light is absorbed.

[0122] On the other hand, when no region with different orientations of the liquid crystal molecules 2401 is found in the liquid crystal layer 240 when viewed from above, the polarization direction of light incident on the liquid crystal layer 240 and the orientation direction of the liquid crystal molecules 2401 in the liquid crystal layer 240 are arranged substantially orthogonally (also referred to as substantially vertically) when viewed from above (see FIG. Fig. 14B ), so the incident light is not absorbed in the liquid crystal layer 240. That is, the liquid crystal layer 240 is integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent region) (refer to Fig.14A In this case, light from all directions of the backlight source 40 passes through the liquid crystal panel 20 (see Fig.14A ). As a result, light from the back side can be transmitted from the lower polar angle side to the higher polar angle side without loss, so a wide viewing angle mode can be achieved with high brightness.

[0123] Here, in order to find regions with different orientations of the liquid crystal molecules 2401 in the liquid crystal layer 240 when viewed from above (i.e., regions with different electric fields in the liquid crystal layer 240), it is important that the voltage difference V1 between the first electrode 231 and the fourth electrode 233, the voltage difference V2 between the second electrode 2321 and the third electrode 2322, the voltage difference V3 between the first electrode 231 and the second electrode 2321, and the voltage difference V4 between the third electrode 2322 and the fourth electrode 233 are all within a sufficient range. In this way, by achieving a state in which regions with different orientations of the liquid crystal molecules 2401 are found in the liquid crystal layer 240 when viewed from above, the liquid crystal layer 240 itself functions as a grid. Specifically, V1, V2, V3, and V4 are values ​​exceeding 0V, respectively. Preferably, they are each greater than 2V. In addition, the voltage differences V1 and V2 are equivalent to the voltages of the longitudinal electric field, and the voltage differences V3 and V4 are equivalent to the voltages of the transverse electric field.

[0124] As an example of effective voltage application in this embodiment, the following aspects can be cited, for example. As an example where the voltages of the longitudinal electric field and the transverse electric field are the same, for example, Fig. 15C and Fig.15D As shown, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 can be set to 0V, 5V, 0V, and 5V, respectively, or to 0V, 5V, 10V, and 5V, respectively. In these cases, V1, V2, V3, and V4 are all 5V. As an example of the same voltage as the longitudinal electric field, for example, Fig.15E and Fig.15FAs shown, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 can be set to 0 V, 3 V, 8 V, and 5 V, respectively, and to 1 V, 8 V, 3 V, and 6 V, respectively. In the former method, V1 and V2 become 5 V, and V3 and V4 become 3 V, and in the latter method, V1 and V2 become 5 V, V3 becomes 7 V, and V4 becomes 3 V. As an example of the same voltage as the transverse electric field, for example, Figure 15G As shown, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 are set to 0V, 4V, 1V, and 5V, respectively. In this case, V1 becomes 5V, V2 becomes 3V, and V3 and V4 become 4V.

[0125] also, Figure 15C to Figure 15G This is an example of effective voltage application in this embodiment. Figure 15C to Figure 15G This is an example of using liquid crystal molecules whose orientation fully follows the voltage at a voltage of 3V. In these drawings, the portion from the first electrode 231 to the fourth electrode 233 in the liquid crystal panel 20 is described with attention. In each drawing, the voltage value recorded in brackets in each reference numeral representing an electrode is the input voltage to the electrode. The voltage value (value indicated by the arrow) inside the drawing is the voltage difference between the voltages. Figure 15D to Figure 15G In the figure, the voltage applying units 263 and 264 are omitted.

[0126] In contrast, for example, when the voltage of the transverse electric field is 0V (for example, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 are set to 5V, 5V, 0V, and 0V, respectively, and 0V, 0V, 5V, and 5V, respectively), no region with different electric fields is generated in the liquid crystal layer 240. That is, only the longitudinal electric field is applied, so the liquid crystal layer 240 cannot function as a grid. In addition, when the voltage of the longitudinal electric field and / or the transverse electric field is 1V (for example, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 are set to 0V, 1V, 0V, and 1V, respectively, 5V, 4V, 0V, and 1V, respectively, and 0V, 5V, 6V, and 1V, respectively), it is also ineffective to discover the grid function based on the liquid crystal layer 240.

[0127] By switching the voltage or appropriately changing the input voltage in this way, it is possible to form an absorption state region (switching region) and a transmission state region (transparent region). Fig.15A The a and a' regions in the ? maintain the transmission state unchanged, while Fig.15AThe c region in the absorbing state becomes Fig.15A The transparent areas a and a' in the graph have transmittances T2 and T3, respectively. Fig.15A The switching region c in the liquid crystal panel 20 has a state of transmittance T4 by absorption (where T1 ≥ T2 > T4, and T1 ≥ T3 > T4). In addition, the front light 1LA of the light incident on the liquid crystal panel 20 from the backlight source 40 passes through the liquid crystal panel 20 without attenuation (see Fig.15A As a result, the light from the backlight source 40 is attenuated on the higher polar angle side, and the light from the back side can be transmitted only on the lower polar angle side with the original brightness, thereby realizing a narrow viewing angle mode.

[0128] (Sixth Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the electrode structure of the liquid crystal panel 20 is different.

[0129] Fig.16 It is a schematic cross-sectional view of the image display device of this embodiment. Fig.17A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the present embodiment. Fig.18A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the present embodiment.

[0130] In this embodiment, if Fig.16 As shown in the figure, the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 231, a first interlayer insulating film 251, a second electrode 2321, a liquid crystal layer 240, a third electrode 2322, a second interlayer insulating film 252, a fourth electrode 233 and a second transparent substrate 220 in order from the observation side to the back side. The liquid crystal panel 20 also includes a first voltage applying unit 265 for applying a voltage between the first electrode 231 and the third electrode 2322, and a second voltage applying unit 266 for applying a voltage between the second electrode 2321 and the fourth electrode 233. In addition, the polarizing plate 141 included in the display panel 10 is arranged opposite to the display panel 10 side (the back side in this embodiment) of the liquid crystal panel 20.

[0131] The first electrode 231 is disposed in a planar shape on the entire surface of the first transparent substrate 210. That is, the first electrode 231 is a solid electrode that covers the first transparent substrate 210. In addition, the fourth electrode 233 is disposed in a planar shape on the entire surface of the second transparent substrate 220. That is, the fourth electrode 233 is a solid electrode that covers the second transparent substrate 220. The first electrode 231 and the fourth electrode 233 may be transparent electrodes. Examples of the transparent electrodes are as described above.

[0132] The second electrode 2321 is configured to be striped when viewed from above. The third electrode 2322 is also configured to be striped when viewed from above. The second electrode 2321 and the third electrode 2322 are arranged in a staggered manner so as not to face each other. That is, the third electrode 2322 is arranged in the non-overlapping area of ​​the second electrode 2321, and the second electrode 2321 is arranged in the non-overlapping area of ​​the third electrode 2322 (see Fig.16 ). In this embodiment, both the second electrode 2321 and the third electrode 2322 are equivalent to the electrode A. Therefore, this embodiment is a mode in which the second electrode 2321 is equivalent to the electrode A and the fourth electrode 233 is equivalent to the electrode B, and also a mode in which the third electrode 2322 is equivalent to the electrode A and the first electrode 231 is equivalent to the electrode B. The second electrode 2321 and the third electrode 2322 may be transparent electrodes. Examples of transparent electrodes are as described above.

[0133] By configuring the electrodes A (in the present embodiment, the second electrode 2321 and the third electrode 2322) to be striped when viewed from above, and configuring the second electrode 2321 and the third electrode 2322 to be non-opposite, the liquid crystal layer 240 has an overlapping area 2411 overlapping with the second electrode 2321, an overlapping area 2412 overlapping with the third electrode 2322, and a non-overlapping area 242 that does not overlap with either the second electrode 2321 or the third electrode 2322.

[0134] The width of the electrode A can be appropriately set in consideration of the desired switching effect and viewing angle. For example, the ratio (W1 / W2) of the width W1 of the non-overlapping region 242 that does not overlap with the second electrode 2321 and the third electrode 2322 and the width W2 of either the overlapping region 2411 overlapping with the second electrode 2321 or the overlapping region 2412 overlapping with the third electrode 2322 can be 1 / 2 to 1 / 20 or 1 / 3 to 1 / 10.

[0135] In this embodiment, the switching region is designed to switch between the transmission state and the absorption state according to the application or non-application of the voltage between the first electrode 231 and the third electrode 2322 (265) and between the second electrode 2321 and the fourth electrode 233 (266). Fig.18A c) in the figure becomes the switching region, and the overlapping region 2411 (equivalent to Fig.18A a”), and an overlapping region 2412 (equivalent to Fig.18A a) in the figure becomes a transparent area. In addition, although not explicitly shown in the figure, the boundary portion between the non-overlapping area 242 and the overlapping area 2411 or the overlapping area 2412 also becomes a switching area. The voltage applying unit only needs to be a power source that can be turned on / off.

[0136] In this embodiment, as described later, in the wide viewing angle mode (see Fig.17A and Fig. 17B ), the liquid crystal layer 240 has a certain transmittance T1. On the other hand, in the narrow viewing angle mode (refer to Fig.18A and Fig.18B )Down, Fig.18A The transparent areas a and a" have transmittances T2 and T3 respectively. Fig.18A The switching region c in the embodiment has a transmittance T4 due to absorption. Among them, T1, T2, T3 and T4 satisfy the relationship of "T1 ≥ T2 > T4" and "T1 ≥ T3 > T4". The magnitude relationship between T2 and T3 is not limited. The transmittance T1 may be 100%, and T4 may be 0%.

[0137] Fig. 17B This is used for the wide viewing angle mode ( Fig.17A ) is a diagram for explaining the orientation direction (initial orientation direction) of the liquid crystal molecules 2401 under the condition of Fig.17A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 17B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Fig.18B This is used for the narrow viewing angle mode ( Fig.18A ) is a diagram illustrating the orientation direction of the liquid crystal molecules 2401 under the condition of Fig.18A Figure XX' portion of the liquid crystal layer 240 (top view). Fig.18B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above).

[0138] like Fig.17A and Fig.18A As shown, light enters the liquid crystal panel 20 from the back side (specifically, the backlight source 40) via the display panel 10. In a state where no voltage is applied between the first electrode 231 and the third electrode 2322 (265), and no voltage is applied between the second electrode 2321 and the fourth electrode 233 (266) (voltage non-applied state), the polarization direction of light incident on the liquid crystal layer 240 and the orientation direction of the liquid crystal molecules 2401 in the liquid crystal layer 240 are substantially orthogonal when viewed from above (refer to FIG. 1 ). Fig. 17B ), so the incident light is not absorbed in the liquid crystal layer 240. That is, the liquid crystal layer 240 is integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent region) (refer to Fig.17AIn this case, light from all directions of the backlight source 40 passes through the liquid crystal panel 20 (see Fig.17A ). As a result, light from the back side can be transmitted from the lower polar angle side to the higher polar angle side without loss, so a wide viewing angle mode can be achieved with high brightness.

[0139] On the other hand, in a state (voltage applied state) where a voltage is applied between the first electrode 231 and the third electrode 2322 (265) and a voltage is also applied between the second electrode 2321 and the fourth electrode 233 (266), the liquid crystal layer 240 itself functions as a grid. That is, among the light incident on the liquid crystal layer 240 from the backlight source 40, the oblique light 1LB and a part of the front light 1LA are reflected in the non-overlapping area 242 ( Fig.18A The light is absorbed (attenuated) in the c region in FIG. 1 and passes through the liquid crystal panel 20 (refer to FIG. 1 ). Fig.18A Specifically, in the overlapping area 2412 ( Fig.18A In the region a in the figure, a longitudinal electric field is generated between the first electrode 231 and the third electrode 2322, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. Fig.18A In the a" region in the display panel 10), a longitudinal electric field is generated between the second electrode 2321 and the fourth electrode 233, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizer 141 of the display panel 10 (front view), so that the incident light is transmitted without being absorbed. In contrast, in the non-overlapping region 242 ( Fig.18A In the c region in the display panel 10, a lateral electric field is generated between the first electrode 231 and the second electrode 2321, and between the third electrode 2322 and the fourth electrode 233, and the orientation direction of the liquid crystal molecules 2401 changes by approximately 90° when viewed from above. Therefore, the liquid crystal molecules 2401 are arranged along the electric field direction. In this case, the polarization direction of the light incident through the polarizer 141 of the display panel 10 is consistent with the orientation direction of the liquid crystal molecules 2401, so the incident light is absorbed.

[0140] By switching the voltage in this way, it is possible to form an absorption state region (switching region) and a transmission state region (transparent region). Fig.18A The a and a" areas in the image remain in the same transmission state, while Fig.18A The c region in the absorbing state becomes Fig.18A The transparent areas a and a" have transmittances T2 and T3 respectively. Fig.18AThe switching region c in the liquid crystal panel 20 has a state of transmittance T4 by absorption (where T1 ≥ T2 > T4 and T1 ≥ T3 > T4). In addition, the front light 1LA of the light incident on the liquid crystal panel 20 from the backlight source 40 passes through the liquid crystal panel 20 without attenuation (see Fig.18A As a result, the light from the backlight source 40 is reduced on the higher polar angle side, and the light from the back side can be transmitted only on the lower polar angle side with the original brightness, so that a narrow viewing angle mode can be achieved.

[0141] (Seventh Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the electrode structure of the liquid crystal panel 20 is different.

[0142] Fig.19 It is a schematic cross-sectional view of the image display device of this embodiment. Fig. 20A This is a schematic cross-sectional view for explaining the wide viewing angle mode of the image display device according to the present embodiment. Fig.21A This is a schematic cross-sectional view for explaining the narrow viewing angle mode of the image display device according to the present embodiment.

[0143] In this embodiment, if Fig.19 As shown in FIG. 1 , the liquid crystal panel 20 includes a first transparent substrate 210, a first electrode 2321, a liquid crystal layer 240, a second electrode 2322, and a second transparent substrate 220 in order from the observation side toward the back side. The liquid crystal panel 20 also includes a voltage applying unit 264 for applying a voltage between the first electrode 2321 and the second electrode 2322. In addition, the polarizing plate 141 included in the display panel 10 is arranged opposite to the display panel 10 side (the back side in this embodiment) of the liquid crystal panel 20.

[0144] The first electrode 2321 is configured to be striped when viewed from above. The second electrode 2322 is also configured to be striped when viewed from above. The first electrode 2321 and the second electrode 2322 are configured to be substantially opposite to each other. In this embodiment, both the first electrode 2321 and the second electrode 2322 are equivalent to the electrode A. Therefore, in this embodiment, the first electrode 2321 is equivalent to the electrode A, the second electrode 2322 is equivalent to the electrode B, and the second electrode 2322 is equivalent to the electrode A, and the first electrode 2321 is equivalent to the electrode B.

[0145] By configuring the electrodes A (the first electrode 2321 and the second electrode 2322 in the present embodiment) to be striped when viewed from above, and configuring the first electrode 2321 and the second electrode 2322 to be approximately opposite, the liquid crystal layer 240 has an overlapping area 241 that overlaps with the first electrode 2321 and the second electrode 2322, and a non-overlapping area 242 that does not overlap with either the first electrode 2321 or the second electrode 2322.

[0146] In this embodiment, the switching region is designed to switch between the transmission state and the absorption state according to whether the voltage (264) between the first electrode 2321 and the second electrode 2322 is applied or not. Fig.21A c) in the figure becomes the switching area, and the portion of the boundary portion c (equivalent to Fig.21A a), and the portion where the boundary portion c is removed from the non-overlapping region 242 (equivalent to Fig.21A d) in the figure becomes a transparent area. In addition, the voltage applying unit only needs to be a power source that can be turned on / off.

[0147] In this embodiment, as described later, in the wide viewing angle mode (see Fig. 20A and Fig. 20B ), the liquid crystal layer 240 has a certain transmittance T1. On the other hand, in the narrow viewing angle mode (refer to Fig.21A and Fig. 21B )Down, Fig.21A The transparent areas a and d in the graph have transmittances T2 and T3 respectively. Fig.21A The switching region c in the embodiment has a transmittance T4 due to absorption. Among them, T1, T2, T3 and T4 satisfy the relationship of "T1 ≥ T2 > T4" and "T1 ≥ T3 > T4". The magnitude relationship between T2 and T3 is not limited. The transmittance T1 may be 100%, and T4 may be 0%.

[0148] Fig. 20B This is used for the wide viewing angle mode ( Fig. 20A ) is a diagram for explaining the orientation direction (initial orientation direction) of the liquid crystal molecules 2401 under the condition of Fig. 20A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 20B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Fig. 21B and Fig. 21C This is used for the narrow viewing angle mode ( Fig.21A ) is a diagram for explaining the alignment direction of the liquid crystal molecules 2401 under. Specifically, Fig. 21B Observe from the side Fig.21A Figure XX' portion of the liquid crystal layer 240 (top view). Fig. 21B Below , the transmission axis direction of the polarizing plate 141 included in the display panel 10 is indicated by an arrow (when viewed from above). Fig. 21C is from Fig.21A Only the liquid crystal panel 20 is selected and the orientation of the liquid crystal molecules 2401 is studied (cross-sectional view). Fig. 21C The dashed lines in the figure represent electric power lines.

[0149] like Fig. 20A and Fig.21A As shown, light enters the liquid crystal panel 20 from the back side (specifically, the backlight source 40) via the display panel 10. When no voltage is applied between the first electrode 2321 and the second electrode 2322 (264) (voltage non-applied state), the polarization direction of the light incident on the liquid crystal layer 240 and the orientation direction of the liquid crystal molecules 2401 in the liquid crystal layer 240 are substantially orthogonal (also referred to as substantially vertical) when viewed from above (see Fig. 20B ), so the incident light is not absorbed in the liquid crystal layer 240. That is, the liquid crystal layer 240 is integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent region) (refer to Fig. 20A In this case, light from all directions of the backlight source 40 passes through the liquid crystal panel 20 (see Fig. 20A ). As a result, light from the back side can be transmitted from the lower polar angle side to the higher polar angle side without loss, so a wide viewing angle mode can be achieved with high brightness.

[0150] On the other hand, when a voltage is applied between the first electrode 2321 and the second electrode 2322 (264) (voltage applied state), the liquid crystal layer 240 itself functions as a grid. That is, among the light incident on the liquid crystal layer 240 from the backlight source 40, the oblique light 1LB and a part of the front light 1LA are reflected at the boundary portion ( Fig.21B The light is absorbed (attenuated) in the c region in FIG. 1 and passes through the liquid crystal panel 20 (refer to FIG. 1 ). Fig.21B Specifically, in the area mainly corresponding to the overlapping area 241 ( Fig.21A In the region a in FIG. 1 , a longitudinal electric field is generated between the first electrode 2321 and the second electrode 2322, and the liquid crystal molecules 2401 are oriented approximately perpendicular to the transmission axis of the polarizing plate 141 of the display panel 10 (front view) (see FIG. Fig. 21C Therefore, the incident light is transmitted without being absorbed. In the area mainly corresponding to the non-overlapping area 242 ( Fig.21AIn the d region in FIG. 1 , since no voltage is applied, the liquid crystal molecules 2401 are not affected by the electric field, and thus maintain their initial orientation (see FIG. 1 ). Fig. 21C In contrast, at the boundary portion ( Fig.21A In the c region in FIG. 1 , the liquid crystal molecules 2401 are arranged along the electric field extending from the electrode width of the first electrode 2321 and the second electrode 2322 (refer to Fig. 21C In this case, the polarization direction of the light incident through the polarizing plate 141 of the display panel 10 is consistent with the alignment direction of the liquid crystal molecules 2401, so the incident light is absorbed.

[0151] By switching the voltage in this way, it is possible to form an absorption state region (switching region) and a transmission state region (transparent region). Fig.21A The a and d regions in the image remain in the same transmission state, while Fig.21A The c region in the absorbing state becomes Fig.21A The transparent areas a and d in the graph have transmittances T2 and T3 respectively. Fig.21A The switching region c in the liquid crystal panel 20 has a state of transmittance T4 by absorption (where T1 ≥ T2 > T4, T1 ≥ T3 > T4). In addition, the front light 1LA of the light incident on the liquid crystal panel 20 from the backlight source 40 passes through the liquid crystal panel 20 without attenuation (see Fig.21A As a result, the light from the backlight source 40 is attenuated on the higher polar angle side, and the light from the back side can be transmitted only on the lower polar angle side with the original brightness, so that a narrow viewing angle mode can be achieved.

[0152] (Eighth Embodiment) In this embodiment, the features unique to this embodiment are mainly described, and the description of the contents overlapped with those of the first embodiment is omitted. This embodiment is substantially the same as the first embodiment except that the display panel 10 is a self-luminous display panel.

[0153] Fig. 22 is a cross-sectional schematic diagram of the image display device involved in this embodiment. Fig. 22 As shown in the figure, the image display device 1 of this embodiment includes the liquid crystal panel 20 of this embodiment (the voltage applying unit is not shown), and a self-luminous display panel as a display panel 10 for displaying an image. An adhesive layer 150 for bonding the display panel 10 and the liquid crystal panel 20 is usually provided between them. The image display device of this embodiment has a self-luminous display panel as the display panel 10, so a backlight is not required.

[0154] In this embodiment, the display panel 10 (self-luminous display panel) has a structure in which a self-luminous layer is sandwiched between a pair of substrates (see Fig. 22 ), but there is no particular limitation as long as it is a self-luminous display panel. For example, there can be cited an organic electroluminescent (EL) display panel, a Micro-LED display panel that uses tiny LEDs in micrometers (μm) as RGB elements, and the like. In the present invention, the viewing angle can be controlled by the liquid crystal panel 20 regardless of the presence or absence of a backlight source. Therefore, it is very useful to be able to combine the liquid crystal panel 20 with a self-luminous display panel.

[0155] As mentioned above, although embodiment of this invention was described, each matter described is applicable to the whole present invention.

[0156] The present invention is further described in detail by enumerating embodiments and comparative examples below, but the present invention is not limited to these embodiments. In addition, the image display devices of the following embodiments can cope with the usual liquid crystal process, do not produce moire fringes, and have excellent viewing angle performance and grid function. In addition, on the basis of being able to achieve a wide viewing angle mode with high brightness, the thickness, weight and manufacturing cost of the image display device can also be suppressed.

[0157] (Example 1) The image display device of Example 1 corresponds to the image display device of the first embodiment described above (see Figure 1 to Figure 4C The size of the display panel 10 is set to 11-inch, the resolution is set to FHD, and the pixel pitch (the width of the pixel in the extension direction of the gate line × the width of the pixel in the extension direction of the source line) is set to 42μm×126μm. Table 1 shows various design values ​​of the liquid crystal panel 20. In the embodiments described below, the display panel 10 and the backlight 40 use the same components as those of the first embodiment unless otherwise specified. Various designs and structures of the liquid crystal panel 20 are also the same as those of the first embodiment unless otherwise specified.

[0158]

Table 1

[0159] Fig.23A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this embodiment. Fig. 23BThis is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this embodiment. I (231) is a waveform diagram of the voltage of the first electrode 231, II (232) is a waveform diagram of the voltage of the second electrode 232, and III (233) is a waveform diagram of the voltage of the third electrode 233. The horizontal axis represents time, and the vertical axis represents voltage (V). The driving voltage is appropriately set and is not limited to this voltage setting.

[0160] In this embodiment, the first electrode 231 (I) functions as a common electrode, and the non-overlapping region 242 is electrically controlled by a voltage applying unit between the first electrode 231 (I) and the third electrode 233 (III), and the overlapping region 241 is electrically controlled by a voltage applying unit between the first electrode 231 (I) and the second electrode 232 (II). Figure 4A Areas a and b in the image become transparent areas. Figure 4A The c area in the figure becomes the switching area.

[0161] (Example 2) The image display device of this embodiment corresponds to the image display device of the second embodiment described above (see Figure 2B , Figures 7A to 9B ). As the liquid crystal molecules 2401, the same as the above-mentioned embodiment 1 is used except that liquid crystal molecules having a negative dielectric anisotropy (Δε) are used.

[0162] (Example 3) The image display device of this embodiment corresponds to the image display device of the third embodiment described above (see Figure 2B , Figure 2C and Fig.10 ). The configuration of the liquid crystal panel 20 and the display panel 10 is opposite to that of the first embodiment, and the transmission axis of the polarizer 142 provided on the liquid crystal panel 20 side of the display panel 10 is substantially perpendicular to the initial alignment direction of the liquid crystal molecules 2401 included in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above.

[0163] (Example 4) The image display device of this embodiment corresponds to the image display device of the fourth embodiment described above (see Figure 2B , Figure 2C and Fig.11 ). Except for the difference in the layer structure (layer configuration) of the liquid crystal panel 20, the embodiment is the same as the above-mentioned embodiment 1. The transmission axis of the polarizer 141 provided on the liquid crystal panel 20 side of the display panel 10 is substantially perpendicular to the initial alignment direction of the liquid crystal molecules 2401 included in the liquid crystal layer 240 of the liquid crystal panel 20 when viewed from above.

[0164] (Example 5) The image display device of this embodiment corresponds to the image display device of the fifth embodiment ( Figure 2B , Figure 2C and Figure 13 to Figure 15C ). Except for the different electrode structure of the liquid crystal panel 20, the present invention is substantially the same as the first embodiment. In this example, the input voltages to the first electrode 231, the second electrode 2321, the third electrode 2322, and the fourth electrode 233 are set to 0V, 10V, 0V, and 10V, respectively (refer to Fig. 15C In addition Fig. 15C In the example, the input voltage to the second electrode and the fourth electrode is recorded as 5 V respectively, but in this example, it is set to 10 V as mentioned above. ).

[0165] Fig.24A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this embodiment. Fig. 24B This is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this embodiment. I (231) is a waveform diagram of the voltage of the first electrode 231, II (2321) is a waveform diagram of the voltage of the second electrode 2321, III (2322) is a waveform diagram of the voltage of the third electrode 2322, and IV (233) is a waveform diagram of the voltage of the fourth electrode 233. The horizontal axis represents time, and the vertical axis represents voltage (V). The driving voltage is appropriately set and is not limited to this voltage setting.

[0166] In this embodiment, the non-overlapping region 242 is electrically controlled by a voltage applying unit between the first electrode 231 (I) and the fourth electrode 233 (IV), and the overlapping region 241 is electrically controlled by a voltage applying unit between the second electrode 2321 (II) and the third electrode 2322 (III). Fig.15A The a area and a' area in the image become transparent areas. Fig.15A The c area in the figure becomes the switching area.

[0167] (Example 6) The image display device of this embodiment corresponds to the image display device of the sixth embodiment described above (see Figure 2B , Figure 2C and Figure 16 to Figure 18B ). Except for the difference in the electrode structure of the liquid crystal panel 20, the present invention is substantially the same as the first embodiment.

[0168] Fig.25A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this embodiment. Fig.25BThis is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this embodiment. I (231) is a waveform diagram of the voltage of the first electrode 231, II (2321) is a waveform diagram of the voltage of the second electrode 2321, III (2322) is a waveform diagram of the voltage of the third electrode 2322, and IV (233) is a waveform diagram of the voltage of the fourth electrode 233. The horizontal axis represents time, and the vertical axis represents voltage (V). The driving voltage is appropriately set and is not limited to this voltage setting.

[0169] In this embodiment, the overlapping region 241 is electrically controlled by a voltage applying unit between the first electrode 231 (I) and the third electrode 2322 (III), and a voltage applying unit between the second electrode 2321 (II) and the fourth electrode 233 (IV). Fig.18A The a and a" areas in the image become transparent areas. Fig.18A The c area in the figure becomes the switching area.

[0170] (Example 7) The image display device of this embodiment corresponds to the image display device of the seventh embodiment (see Figure 2B , Figure 2C and Figures 19 to 21C ). Except for the difference in the electrode structure of the liquid crystal panel 20, the present invention is substantially the same as the first embodiment.

[0171] Fig.26A This is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this embodiment. Fig.26B 2 is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this embodiment. I (2321) is a waveform diagram of the voltage of the first electrode 2321, and II (2322) is a waveform diagram of the voltage of the second electrode 2322. The horizontal axis represents time, and the vertical axis represents voltage (V). The driving voltage is appropriately set and is not limited to this voltage setting.

[0172] In this embodiment, the overlapping region 241 and the non-overlapping region 242 are electrically controlled by a voltage applying unit between the first electrode 2321 (I) and the second electrode 2322 (II). Fig.21A The a and d areas in the image become transparent areas. Fig.21A The c area in the figure becomes the switching area.

[0173] (Example 8) The image display device of this embodiment corresponds to the image display device of the eighth embodiment described above (see Figure 2B , Figure 2C and Fig. 22). As in this embodiment, even when combined with a self-luminous display panel, it is possible to realize an image display device with excellent viewing angle performance while suppressing thickness, weight and manufacturing cost.

[0174] The various aspects of the present invention described above may be appropriately combined within the scope not departing from the gist of the present invention. Description of Reference Numerals

[0175] 1. 1R Image display device 1LA Frontal light 1LB Light in oblique direction 10. 10R display panel 20, 20R LCD panel 40 Backlight 110 Color filter (CF) substrate 120 Thin Film Transistor (TFT) Substrate 130 Liquid crystal layer 141, 142 Polarizer 150 Adhesive Layer 210, 220 transparent substrate 231, 232, 2321, 2322, 233 electrodes 240 Liquid crystal layer 241, 2411, 2412 overlapping areas 24 2 non-overlapping areas 250, 251, 252 Interlayer insulation film 261, 262, 263, 264, 265, 266 Voltage application unit 2401 Liquid crystal molecules 2402 Dichroic pigments

Claims

1. An image display device, comprising a display panel for displaying an image and a liquid crystal panel, wherein: The display panel at least comprises a polarizing plate. The polarizing plate included in the display panel is arranged opposite to the display panel side of the liquid crystal panel. The liquid crystal panel comprises an electrode A disposed between a pair of transparent substrates at a distance when viewed from above, a liquid crystal layer, and an electrode B disposed opposite to the electrode A via the liquid crystal layer, and the liquid crystal panel comprises a voltage applying unit for applying a voltage between the electrode A and the electrode B. The liquid crystal layer is a guest-host liquid crystal layer including a dichroic dye and liquid crystal molecules, and the liquid crystal layer has an overlapping region overlapping with the electrode A and a non-overlapping region not overlapping with the electrode A. When viewed from above, the transmission axis of the polarizer is substantially perpendicular to the initial alignment direction of the liquid crystal molecules.

2. The image display device according to claim 1, wherein: The liquid crystal layer has a transparent region and a switching region that switches between a transmission state and an absorption state.

3. The image display device according to claim 2, wherein: The transparent region and the switching region are formed of the same material.

4. The image display device according to claim 1, wherein: The electrodes A are arranged in a stripe shape when viewed from above.

5. The image display device according to claim 1, wherein: The liquid crystal panel includes a first transparent substrate, a first electrode, the liquid crystal layer, a second electrode, an interlayer insulating film, a third electrode and a second transparent substrate in sequence. The second electrode is the electrode A, The first electrode is the electrode B, The liquid crystal panel further includes a second voltage applying unit that applies a voltage between the first electrode and the third electrode.

6. The image display device according to claim 1, wherein: The liquid crystal panel includes a first transparent substrate, a first electrode, a first interlayer insulating film, a second electrode, the liquid crystal layer, a third electrode, a second interlayer insulating film, a fourth electrode and a second transparent substrate in this order. One of the second electrode and the third electrode is the electrode A, and the other is the electrode B. The voltage applying unit is a unit that applies a voltage between the second electrode and the third electrode. The liquid crystal panel further includes a third voltage applying unit that applies a voltage between the first electrode and the fourth electrode.

7. The image display device according to claim 1, wherein: The liquid crystal panel includes a first transparent substrate, a first electrode, a first interlayer insulating film, a second electrode, the liquid crystal layer, a third electrode, a second interlayer insulating film, a fourth electrode and a second transparent substrate in this order. At least one of the second electrode and the third electrode is the electrode A, At least one of the first electrode or the fourth electrode is the electrode B, The voltage applying unit includes a first voltage applying unit that applies a voltage between the second electrode and the fourth electrode, and a second voltage applying unit that applies a voltage between the first electrode and the third electrode.

8. The image display device according to claim 1, wherein: The thickness of the non-overlapping region is 30 μm or less.

9. The image display device according to claim 1, wherein: The electrode A and the electrode B are transparent electrodes.

10. The image display device according to claim 5, wherein: The first electrode, the second electrode and the third electrode are transparent electrodes.

11. The image display device according to claim 6 or 7, characterized in that: The first electrode, the second electrode, the third electrode, and the fourth electrode are transparent electrodes.

12. The image display device according to claim 1, wherein: It also has a backlight.

13. The image display device according to claim 12, wherein: The backlight source has a local dimming function.

14. The image display device according to claim 1, wherein: The display panel is a liquid crystal display panel or a self-luminous display panel.

Images