Liquid crystal panel and display device

Abstract

Provided are a liquid crystal panel capable of reducing an optical shading angle in a narrow viewing angle mode and suppressing color shift when viewed head-on, and a display device provided with the above-described liquid crystal panel. The liquid crystal panel is provided with, in order, a first polarizing plate having a first absorption axis, a first substrate having a first electrode, a liquid crystal layer containing liquid crystal molecules, and a second substrate having a second electrode, when an azimuth angle of a director of the liquid crystal molecules on the first substrate side in a no-voltage applied state is set as φ1, an azimuth angle of a director of the liquid crystal molecules on the second substrate side is set as φ2, and an azimuth angle of the first absorption axis of the first polarizing plate is set as φP1, the following (Formula 1) is satisfied, and (Formula 2-1) or (Formula 2-2) is satisfied, 5° ≤ |φ1-φ2| ≤ 20° …… (Formula 1); 5° ≤ |φP1-φ2| ≤ 20° …… (Formula 2-1); 65° ≤ |φP1-φ2| ≤ 80° …… (Formula 2-2).

Description

TECHNICAL FIELD

[0001] The following disclosure relates to a liquid crystal panel and a display device provided with the above-described liquid crystal panel. BACKGROUND

[0002] A liquid crystal panel is a panel that uses a liquid crystal composition in the control of transmitted light, and a representative mode thereof is to apply a voltage to a liquid crystal composition enclosed between a pair of substrates, and change the alignment state of liquid crystal molecules in the liquid crystal composition according to the applied voltage, thereby controlling the amount of light transmission. Such a liquid crystal panel effectively utilizes the thinness, lightness, and low power consumption, and is used in a wide range of fields.

[0003] However, there is currently a study to improve the viewing angle characteristics so that the same image can be observed from a narrow viewing angle range and from a wide viewing angle range, with a display device. On the other hand, from the viewpoint of privacy maintenance, there is a study of a display method in which an image can be observed from a narrow viewing angle range, but it is difficult to observe the above-described image from a wide viewing angle range. In this way, there is a need for a display device that can be switched between a public mode (wide viewing angle mode) in which the same image can be observed in a narrow viewing angle range and in a wide viewing angle range, and a privacy mode (narrow viewing angle mode) in which an image can be observed from a narrow viewing angle range, but it is difficult to observe the image from a wide viewing angle range.

[0004] As a technology related to a liquid crystal panel used in a display device capable of switching between a public mode and a privacy mode, for example, a viewing angle control liquid crystal panel is disclosed in Patent Literature 1, which controls the viewing angle of an image displayed on a display panel by being disposed on the surface or the back surface of the display panel, and includes a liquid crystal layer, and is provided with pixels as units when a voltage is applied to the liquid crystal layer, straight linearly polarized light is incident on the liquid crystal layer, and a polarizing plate is provided on the side of the liquid crystal layer from which light is emitted, which transmits only the component of light emitted from the liquid crystal layer that is parallel to the polarization axis of the straight linearly polarized light incident on the liquid crystal layer, and by applying a voltage to the liquid crystal layer, the liquid crystal molecules contained in the liquid crystal layer are tilted in the direction parallel or perpendicular to the polarization axis of the straight linearly polarized light incident on the liquid crystal layer, and a plurality of the above-described pixels are arranged in a matrix shape.

[0005] Further, in Patent Literature 2, a backlight system for controlling a viewing angle is disclosed, which includes a first backlight unit that irradiates light from a non-viewing side of the backlight system toward a viewing side, a second backlight unit that is disposed on the viewing side of the first backlight unit and irradiates light toward the viewing side of the backlight system, a privacy optical member that includes a liquid crystal material, is disposed on the non-viewing side of the second backlight unit, is disposed between the first backlight unit and the second backlight unit, and transmits light from the first backlight in a limited viewing angle range, a first polarizing plate that is disposed on the viewing side of the privacy optical member and is disposed on the non-viewing side of the second backlight unit, and a second polarizing plate that is disposed on the non-viewing side of the privacy optical member and is disposed on the viewing side of the first backlight unit, the privacy optical member being a hybrid aligned nematic (HAN) mode liquid crystal cell disposed between the first polarizing plate and the second polarizing plate, the HAN mode liquid crystal cell including a first substrate including a first electrode layer, and a second substrate having a second electrode layer disposed on the opposite side through a liquid crystal layer, the viewing angle restriction being strengthened when a voltage is applied to the HAN mode liquid crystal cell.

[0006] Further, in Non-Patent Literature 1, a double-cell type liquid crystal display device is disclosed, which includes a viewing angle control liquid crystal panel composed of a VA (Vertical Alignment) oriented liquid crystal lens cell, an ITO gate electrode provided only on the substrate side on one side, a display liquid crystal panel, and a louver film, which can diffuse a backlight through the louver film by refractive index distribution in a lateral electric field modulation cell when a voltage is applied to the gate electrode of the viewing angle control liquid crystal panel (functions as a public mode), and which does not diffuse the backlight but directly leaks to the display liquid crystal panel side when no voltage is applied (functions as a privacy mode).

[0007] Prior Art Documents

[0008] Patent Literature

[0009] [Patent Literature 1] Japanese Patent Application Publication No. 2008-203565

[0010] [Patent Literature 2] U.S. Patent No. 11002998

[0011] Non-Patent Literature

[0012] Non-Patent Literature 1: AU Optronics Corp., Hsinchu, Taiwan, China, “Advanced Hyper-Viewing Angle Controllable LCD”, SID 2021 DIGEST, 543 SUMMARY

[0013] Technical Problem to be Solved by the Invention

[0014] In the above-described Patent Documents 1 to 2 and Non-Patent Document 1, there is no study on reducing the polar angle (light shielding angle) at which the transmittance reaches the minimum in the narrow viewing angle mode (light shielding angle at which the minimum polar angle is achieved). That is, there is no study on reducing the angle range (polar angle range) that can be visually confirmed in the narrow viewing angle mode. Further, there is also no study on the phenomenon that the hue at the time of front observation differs between the voltage application state and the no-voltage application state (color shift at the time of front observation).

[0015] The present invention has been achieved in view of the above-described circumstances, and aims to provide a liquid crystal panel capable of reducing the light shielding angle in the narrow viewing angle mode and capable of suppressing the color shift at the time of front observation, and a display device having the above-described liquid crystal panel.

[0016] Technical Solution to Solve the Technical Problem

[0017] (1) The liquid crystal panel of one embodiment of the present invention includes, in this order, a first polarizing plate having a first absorption axis, a first substrate having a first electrode, a liquid crystal layer containing liquid crystal molecules, and a second substrate having a second electrode. When an azimuth angle of a director of the liquid crystal molecules on the first substrate side in a no-voltage application state is set to φ1, an azimuth angle of a director of the liquid crystal molecules on the second substrate side is set to φ2, and an azimuth angle of the first absorption axis of the first polarizing plate is set to φP1, the following (Formula 1) is satisfied, and (Formula 2-1) or (Formula 2-2) is satisfied.

[0018] 5° ≤ |φ1 - φ2| ≤ 20°... (Formula 1);

[0019] 5° ≤ |φP1 - φ2| ≤ 20°... (Formula 2-1);

[0020] 65° ≤ |φP1 - φ2| ≤ 80°... (Formula 2-2).

[0021] (2) Further, the liquid crystal panel of one embodiment of the present invention includes, on the basis of the configuration of the above (1), a second polarizing plate on the side of the second substrate opposite to the liquid crystal layer, and the second polarizing plate has a second absorption axis parallel to the first absorption axis.

[0022] (3) Further, the liquid crystal panel of one embodiment of the present invention includes, on the basis of the configuration of the above (1) or the above (2), the first electrode and the second electrode are whole-surface electrodes, and the retardation Re of the liquid crystal layer in the no-voltage application state is greater than or equal to 700 nm and less than or equal to 1200 nm.

[0023] (4) In addition, the liquid crystal panel of one embodiment of the present application is provided on the basis of the configuration of (1) or (2) above, and the pattern visually recognized from the oblique direction of the liquid crystal panel in the case where the liquid crystal layer is in a voltage application state is patterned, and the retardation Re of the liquid crystal layer in a non-voltage application state is greater than or equal to 700 nm and less than or equal to 900 nm.

[0024] (5) In addition, the liquid crystal panel of one embodiment of the present application is provided on the basis of the configuration of (1), (2), (3), or (4) above, and the liquid crystal molecules have positive dielectric anisotropy.

[0025] (6) In addition, the liquid crystal panel of one embodiment of the present application is provided on the basis of the configuration of (1), (2), (3), (4), or (5) above, and further includes a negative C-plate in which the retardation Rth in the thickness direction is greater than or equal to 500 nm.

[0026] (7) In addition, a display device of another embodiment of the present application includes the liquid crystal panel described in any of (1), (2), (3), (4), (5), and (6) above, and a display panel.

[0027] (8) In addition, the display device of one embodiment of the present application is provided on the basis of the configuration of (7) above, and the liquid crystal layer is a first liquid crystal layer, and the display panel includes, in order, a third polarizing plate having a third absorption axis, a second liquid crystal layer, and a fourth polarizing plate, the fourth polarizing plate has a fourth absorption axis orthogonal to the third absorption axis, and the absorption axes of the polarizing plates closer to the liquid crystal panel are parallel to the first absorption axis among the third polarizing plate and the fourth polarizing plate.

[0028] (9) In addition, the display device of one embodiment of the present application is provided on the basis of the configuration of (7) or (8) above, and the display panel is a liquid crystal display panel of an IPS mode or an FFS mode.

[0029] (10) In addition, the display device of one embodiment of the present application is provided on the basis of the configuration of (7), (8), or (9) above, and the display device further includes a backlight, and the backlight includes two light guide plates, one of the two light guide plates functions as a wide viewing angle mode, and the other functions as a narrow viewing angle mode.

[0030] (11) In addition, the display device of one embodiment of the present application is provided on the basis of the configuration of (7) above, and the display panel is an organic EL display panel, an inorganic EL display panel, a micro LED display panel, or a QLED display panel.

[0031] (12) In addition, the display device of one embodiment of the present application includes the display panel including a third substrate, a second liquid crystal layer, and a fourth substrate, the third substrate includes color filters of a plurality of colors, the fourth substrate includes pixel electrodes, the color filters of a plurality of colors and the pixel electrodes each have a long strip shape, and the long side directions of the color filters of a plurality of colors and the pixel electrodes each are arranged in the up-down direction of the display panel.

[0032] (13) In addition, the display device of one embodiment of the present application includes the display panel including a third substrate, a second liquid crystal layer, and a fourth substrate, the third substrate includes color filters of a plurality of colors, the fourth substrate includes pixel electrodes, the color filters of a plurality of colors and the pixel electrodes each have a long strip shape, and the long side directions of the color filters of a plurality of colors and the pixel electrodes each are arranged in the left-right direction of the display panel.

[0033] (14) In addition, the display device of one embodiment of the present application includes the display panel including a third substrate, a second liquid crystal layer, and a fourth substrate, the third substrate includes color filters of a plurality of colors, the fourth substrate includes pixel electrodes, the color filters of a plurality of colors and the pixel electrodes each have a long strip shape, and the long side directions of the color filters of a plurality of colors and the pixel electrodes each are arranged in the left-right direction of the display panel.

[0034] Advantageous Effects

[0035] According to the present application, a liquid crystal panel capable of reducing an angle of light shielding in a narrow viewing angle mode and suppressing color shift in front view and a display device including the liquid crystal panel can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a cross-sectional schematic view of a voltage non-application state of a viewing angle control liquid crystal panel of the first embodiment.

[0037] Figure 2 is a cross-sectional schematic view of a voltage application state of a viewing angle control liquid crystal panel of the first embodiment.

[0038] Figure 3 is a perspective schematic view of a viewing angle control liquid crystal panel of the first embodiment.

[0039] Figure 4 is a front view schematic view of a viewing angle control liquid crystal panel of the first embodiment.

[0040] Figure 5 is a stereoscopic diagram showing the relationship between the director of the liquid crystal molecules in a voltage non-application state and the absorption axis of the polarizing plate of the viewing angle control liquid crystal panel of the first embodiment.

[0041] Figure 6 is a stereoscopic diagram showing the relationship between the director of the liquid crystal molecules in a voltage application state and the absorption axis of the polarizing plate of the viewing angle control liquid crystal panel of the first embodiment.

[0042] Figure 7 is a stereoscopic diagram of the viewing angle control liquid crystal panel of Modification 1 of the first embodiment.

[0043] Figure 8 is a stereoscopic diagram of the viewing angle control liquid crystal panel of Modification 2 of the first embodiment.

[0044] Figure 9 is a cross-sectional schematic view of the display device of the second embodiment.

[0045] Figure 10 is a front view schematic view of the display device of the second embodiment.

[0046] Figure 11 is a cross-sectional schematic view of the display device of Modification 1 of the second embodiment.

[0047] Figure 12 is a front view schematic view of the display device of Modification 1 of the second embodiment.

[0048] Figure 13A is a graph showing one example of the measurement results of the shading angle.

[0049] Figure 13B is a graph showing the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer of the viewing angle control liquid crystal panel of Examples 1 to 4 and Reference Examples 1 to 7.

[0050] Figure 14 is a graph showing the shading angle with respect to the retardation of the first liquid crystal layer of the viewing angle control liquid crystal panel of Examples 1 to 4 and Reference Examples 1 to 7.

[0051] Figure 15 is a cross-sectional schematic view of the display device of Example 5.

[0052] Figure 16 is a front view schematic view of the display device of Example 5.

[0053] Figure 17 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 5.

[0054] Figure 18 is a cross-sectional schematic view of the display device of Example 6.

[0055] Figure 19 is a front surface schematic view of the display device of Example 6.

[0056] Figure 20 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 6.

[0057] Figure 21 is a cross-sectional schematic view of the display device of Example 7.

[0058] Figure 22 is a front surface schematic view of the display device of Example 7.

[0059] Figure 23 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 7.

[0060] Figure 24 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode of the display devices of Example 8-1 to Example 8-4.

[0061] Figure 25 is a view showing the pattern of the first electrode provided in the display device of Example 8-1.

[0062] Figure 26 is a view showing the pattern of the first electrode provided in the display device of Example 8-2. Figure 27 is a view showing the pattern of the first electrode provided in the display device of Example 8-3. Figure 28 is a view showing the pattern of the first electrode provided in the display device of Example 8-4.

[0063] Figure 29 is a view showing one example of the appearance of a sample in the narrow viewing angle mode and the wide viewing angle mode of the display devices of Example 8-1 to Example 8-4.

[0064] Figure 30 is a cross-sectional schematic view of the display device of Example 9.

[0065] Figure 31 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 9.

[0066] Figure 32 is a plan view of a third substrate provided in the display device of Modification 3 of the second embodiment.

[0067] Figure 33 FIG. 7 is a plan view of a fourth substrate provided in a liquid crystal display panel of a display device according to a modification 3 of the second embodiment.

[0068] Figure 34 FIG. 8 is a plan view of a third substrate provided in a liquid crystal display panel of a display device according to a modification 4 of the second embodiment.

[0069] Figure 35 FIG. 9 is a plan view of a fourth substrate provided in a liquid crystal display panel of a display device according to a modification 4 of the second embodiment.

[0070] Figure 36 FIG. 10 is a perspective view of a backlight provided in a display device according to a modification 5 of the second embodiment.

[0071] Figure 37 FIG. 11 is a cross-sectional view for explaining a case where the LEDs provided in the general light guide plate and the LEDs provided in the common light guide plate are in an on state in the backlight provided in the display device according to the modification 5 of the second embodiment.

[0072] Figure 38 FIG. 12 is a cross-sectional view for explaining a case where the LEDs provided in the general light guide plate are in an on state and the LEDs provided in the common light guide plate are in an off state in the backlight provided in the display device according to the modification 5 of the second embodiment.

[0073] Figure 39 FIG. 13 is a cross-sectional view for explaining a case where the LEDs provided in the general light guide plate are in an off state and the LEDs provided in the common light guide plate are in an on state in the backlight provided in the display device according to the modification 5 of the second embodiment.

[0074] Figure 40 FIG. 14 is a perspective view of a backlight provided in a display device according to a modification 6 of the second embodiment. DETAILED DESCRIPTION

[0075] Hereinafter, embodiments of the present application will be described. The present application is not limited to the contents described in the following embodiments, and design changes can be appropriately made within a range satisfying the constitution of the present application. In the following description, the same parts or parts having the same function are commonly and appropriately denoted by the same reference numerals between different drawings, and repeated description thereof is appropriately omitted. Each mode of the present application can be appropriately combined within a range not departing from the gist of the present application.

[0076] [Definition of Terms]

[0077] In the present specification, the observation surface side refers to the side closer to the screen (display surface) of the liquid crystal panel, and the back surface side refers to the side farther from the screen (display surface) of the liquid crystal panel.

[0078] In the present specification, the azimuth refers to the direction when a direction (e.g., a measurement direction) as an object is projected onto the screen of the liquid crystal panel, and is expressed by an angle (azimuth angle) formed with an azimuth as a reference. Here, the azimuth (0°) as a reference is set to the horizontal right direction of the screen of the liquid crystal panel. The azimuth angle is set to a positive angle in the counterclockwise direction and to a negative angle in the clockwise direction. Both the counterclockwise direction and the clockwise direction indicate the direction of rotation when the screen of the liquid crystal panel is observed from the observation surface side (front surface). Furthermore, the angle indicates a value measured in a state where the liquid crystal panel is viewed from above, and the fact that two straight lines (including axes and directions) are orthogonal to each other means that they are orthogonal in a state where the liquid crystal panel is viewed from above, and the fact that two straight lines (including axes and directions) are parallel to each other means that they are parallel in a state where the liquid crystal panel is viewed from above.

[0079] In the present specification, the polar angle refers to the angle formed between the direction (e.g., the measurement direction) as an object and the normal direction of the screen of the liquid crystal panel. When the azimuth angle of the direction as an object is 0° to 90° or 270° to 360°, the polar angle is set to a positive angle, and when the azimuth angle of the direction as an object is 90° to 270°, the polar angle is set to a negative angle.

[0080] In the present specification, the axis azimuth refers to the azimuth of the absorption axis (reflection axis) of the polarizer or the optical axis (slow axis) of the birefringent layer, unless otherwise specified.

[0081] In the present specification, the fact that two axes are orthogonal means that the angle formed between them is 90° ± 3°, preferably 90° ± 1°, more preferably 90° ± 0.5°, and particularly preferably 90° (completely orthogonal). The fact that two axes are parallel means that the angle formed between them is 0° ± 3°, preferably 0° ± 1°, more preferably 0° ± 0.5°, and particularly preferably 0° (completely parallel).

[0082] In the present specification, the in-plane retardation Rp is defined by Rp = (ns - nf) d. Furthermore, the thickness direction retardation Rth is defined by Rth = (nz - (nx + ny) / 2) d. ns refers to the larger one of nx and ny and the smaller one of nf. Furthermore, nx and ny indicate the principal refractive index in the in-plane direction of the birefringent layer (including the liquid crystal panel), nz indicates the principal refractive index in the out-of-plane direction, i.e., the direction perpendicular to the plane of the birefringent layer, and d indicates the thickness of the birefringent layer.

[0083] In addition, in the present specification, the measurement wavelength of the optical parameters such as the principal refractive index and the phase difference is 550 nm, unless otherwise specified.

[0084] In the present specification, a birefringent layer is a layer having optical anisotropy, and is a concept including a liquid crystal panel. Either one of the absolute value of the retardation in the in-plane direction and the retardation in the thickness direction of the birefringent layer has a value of 10 nm or more, and preferably a value of 20 nm or more.

[0085] Hereinafter, an embodiment of the present application will be described. The present application is not limited to the content described in the following embodiment, and design changes can be appropriately made within a range satisfying the configuration of the present application.

[0086] (First Embodiment)

[0087] Figure 1 is a cross-sectional schematic view showing a voltage non-application state of the viewing angle control liquid crystal panel of the first embodiment. Figure 2 is a cross-sectional schematic view showing a voltage application state of the viewing angle control liquid crystal panel of the first embodiment. Figure 3 is a perspective schematic view of the viewing angle control liquid crystal panel of the first embodiment. Figure 4 is a front view schematic view of the viewing angle control liquid crystal panel of the first embodiment.

[0088] As shown in Figures 1-4 , the viewing angle control liquid crystal panel 10 of the present embodiment, which is the above-described liquid crystal panel, sequentially includes a first polarizing plate 10P1 having a first absorption axis 10P1A, a first substrate 110 having a first electrode 112, a liquid crystal layer 130 containing liquid crystal molecules 131, and a second substrate 150 having a second electrode 152. When an azimuth angle of a director 1311A of the liquid crystal molecules 1311 on the first substrate 110 side in a voltage non-application state is set as φ1, an azimuth angle of a director 1312A of the liquid crystal molecules 1312 on the second substrate 150 side is set as φ2, and an azimuth angle of the first absorption axis 10P1A of the first polarizing plate 10P1 is set as φP1, the following (Formula 1) is satisfied, and (Formula 2-1) or (Formula 2-2) is satisfied.

[0089] 5° ≤ |φ1- φ2| ≤ 20°... (Formula 1)

[0090] 5° ≤ |φP1- φ2| ≤ 20°... (Formula 2-1)

[0091] 65° ≤ |φP1- φ2| ≤ 80°... (Formula 2-2)

[0092] By satisfying the above (Formula 1), color shift at the time of front observation can be suppressed. Whether φ1 > φ2 or φ1 < φ2, the same effect can be obtained in either case. Further, by satisfying the above (Formula 2-1) or (Formula 2-2), the viewing angle control liquid crystal panel 10 functions as a wide viewing angle mode in the no-voltage application state, and functions as an asymmetric narrow viewing angle mode with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) in the voltage application state. Specifically, the viewing angle control liquid crystal panel 10 has a polar angle (light shielding angle) at which the transmittance is the smallest on the positive polar angle side and the negative polar angle side, and the absolute values of the light shielding angle on the negative polar angle side and the light shielding angle on the positive polar angle side are different from each other. In particular, in this narrow viewing angle mode, the light shielding angle on the negative polar angle side can be reduced to, for example, polar angle -40°-30°, the angle range (polar angle range) in which the angle can be visually recognized can be sufficiently reduced, and a sufficient light shielding effect can be obtained. In addition, in either case of satisfying the above (Formula 2-1) or (Formula 2-2), the retardation of the viewing angle control liquid crystal panel 10 (preferably, an ECB (Electrically Controlled Birefringene) mode) satisfies λ / 2 [nm] at the desired light shielding angle (polar angle direction), so the same light shielding effect can be obtained in either case of satisfying the above (Formula 2-1) or (Formula 2-2). In this specification, the light shielding angle is small means that the absolute value of the light shielding angle is small.

[0093] Here, as the constitution of the liquid crystal panel, for example, a longitudinal electric field mode can be cited: a pair of substrates sandwiching a liquid crystal layer therebetween, one of the pair of substrates sandwiching a pixel electrode, the other of the pair of substrates forming a common electrode, a longitudinal electric field being applied to the liquid crystal layer by applying a voltage between the pixel electrode and the common electrode, and display being performed thereby.

[0094] As the longitudinal electric field mode, an ECB mode in which liquid crystal molecules in the liquid crystal layer are aligned in parallel with the substrate surface, i.e., homogeneous (horizontal) alignment in the no-voltage application state, a VA (Vertical Alignment) mode in which liquid crystal molecules in the liquid crystal layer are aligned perpendicularly to the substrate surface, i.e., homeotropic (vertical) alignment in the no-voltage application state, a HAN (Hybrid Aligned Nematic) mode, and the like can be cited.

[0095] The director of the liquid crystal molecules on the first substrate side is the director of the liquid crystal molecules oriented horizontally in the vicinity of the first substrate. More specifically, in the case where the alignment film provided on the liquid crystal layer side of the first substrate is a horizontal alignment film, the director of the liquid crystal molecules on the first substrate side refers to the director of the liquid crystal molecules located at the interface on the first substrate side of the liquid crystal layer. In the case where the alignment film provided on the liquid crystal layer side of the first substrate is a vertical alignment film, since the liquid crystal molecules located at the interface on the first substrate side of the liquid crystal layer are vertically aligned, the director of the liquid crystal molecules on the first substrate side refers to the director of the liquid crystal molecules located at the inner side of the liquid crystal layer further from the interface on the first substrate side in a horizontally aligned state. Since the director of the liquid crystal molecules is the direction of the alignment axis (the direction in which the long axis of the molecules is aligned on average in nematic liquid crystals), the azimuth of the director of the liquid crystal molecules on the first substrate side in the no-voltage application state coincides with the azimuth of the alignment treatment direction of the alignment film provided on the liquid crystal layer side of the first substrate.

[0096] Likewise, the director of the liquid crystal molecules on the second substrate side is the alignment direction of the liquid crystal molecules aligned horizontally in the vicinity of the second substrate. More specifically, in the case where the alignment film provided on the liquid crystal layer side of the second substrate is a horizontal alignment film, the alignment direction of the liquid crystal molecules on the second substrate side refers to the director of the liquid crystal molecules located at the interface on the second substrate side of the liquid crystal layer. In the case where the alignment film provided on the liquid crystal layer side of the second substrate is a vertical alignment film, since the liquid crystal molecules located at the interface on the second substrate side of the liquid crystal layer are vertically aligned, the director of the liquid crystal molecules on the second substrate side refers to the director of the liquid crystal molecules located at the inner side of the liquid crystal layer further from the interface on the second substrate side in a horizontally aligned state. The azimuth of the director of the liquid crystal molecules on the second substrate side in the no-voltage application state coincides with the azimuth of the alignment treatment direction of the alignment film provided on the liquid crystal layer side of the second substrate.

[0097] The alignment state of the liquid crystal molecules can also be analyzed as follows. When the extinction position is observed when a liquid crystal panel in a no-voltage application state is sandwiched between a pair of polarizing plates configured as crossed Nicols, either one of a (state 1) parallel (horizontal) alignment state or a (state 2) vertical alignment (vertical) alignment state can be specified, and it is determined that there is no twist. At this time, in the case where the extinction position is not observed, only one of the pair of polarizing plates configured as crossed Nicols is rotated in the azimuthal direction, and it is assumed that the extinction position is observed when the rotation is counterclockwise by 10°, then the liquid crystal molecules in the liquid crystal panel are either one of (state 1) or (state 2), and are also specified as a state in which the liquid crystal molecules are twisted by 10° in the no-voltage application state.

[0098] As the division of the state 1 and (state 2), if the voltage dependence of the in-plane phase difference is measured in Axoscan (manufactured by Axometrics, Inc.), it is possible to make the division of whether it is the ECB mode or whether it is other modes (for example, HAN mode, VA mode, and the like) by the characteristic curve. In addition, in the ECB mode, there is a clear threshold in the voltage dependence of the in-plane phase difference, but since there is no threshold in the HAN mode, it is possible to make the division.

[0099] Whether the liquid crystal molecules are horizontally oriented or vertically oriented can be determined by using Axoscan (manufactured by Axometrics, Inc.) and measuring the in-plane phase difference with no voltage application. In the horizontally oriented state and without twist, the in-plane phase difference: (ne-no) x d is obtained, and in the case of 10° twist, the in-plane phase difference: { (ne-no) x cos 5°} x d is obtained. Here, ne represents the major axis refractive index of the liquid crystal molecules, no represents the minor axis refractive index of the liquid crystal molecules, and d represents the gap (thickness of the liquid crystal layer). On the other hand, in the case of the vertically oriented state, only the light of the minor axis refractive index is felt, and the in-plane phase difference with no voltage application is about 0 nm, so the difference from the horizontally oriented state becomes clear. In addition, in the case of 10° twist, cos 5° is provided in the formula of the in-plane phase difference because the liquid crystal molecules are twisted (total) 10° in the thickness direction phase by phase, so the average is 5°.

[0100] A more detailed analysis of the orientation state of the liquid crystal molecules (including the director) can be performed by using Axoscan (manufactured by Axometrics, Inc.) and performing biaxial tilt phase difference measurement (cell tilt phase difference measurement), and more specifically, it is possible to perform in-plane phase difference measurement of the liquid crystal panel to a polar angle 0° (front surface) to a polar angle ±60° in the biaxial (azimuth 2 direction). It is also possible to estimate the director of the liquid crystal molecules (including information on the specific tilt angle) based on the measurement results.

[0101] The viewing angle control liquid crystal panel 10 of the present embodiment is preferably in the ECB mode, and by satisfying the above (Formula 2-1) or (Formula 2-2), it is possible to obtain a horizontal direction left-right asymmetry in the luminance viewing angle with respect to the front surface (polar angle 0°) when a voltage is applied to the liquid crystal layer 130, and it is possible to achieve a polar angle (also referred to as an occlusion angle) at which the transmittance is the minimum at a smaller angle. That is, it is possible to achieve an ECB mode liquid crystal panel having an asymmetric viewing angle that can occlude at a lower polar angle. As a result, by using the viewing angle control liquid crystal panel 10 of the present embodiment, it is possible to further narrow the angle range (polar angle range) that can be visually recognized in the privacy mode.

[0102] Further, the present inventors found that, when the liquid crystal panel of the ECB mode having the asymmetric viewing angle is observed from the front, there is a room for improvement in that color shift occurs between the voltage application state and the no-voltage application state. For example, in the liquid crystal panel of the ECB mode having the asymmetric viewing angle, it was found that if the azimuth angle of the first absorption axis of the first polarizing plate is 90° and the azimuth angle of the director of the liquid crystal molecules in the no-voltage application state is 75°, the incident polarized light feels different birefringence for each color, and thus the color tone of the front observation has a tendency to shift between the voltage application state and the no-voltage application state. The viewing angle control liquid crystal panel 10 of the present embodiment satisfies the above (Formula 1), and within the liquid crystal layer 130, the liquid crystal molecules 131 are twisted and aligned with a twist angle φ = |φ1- φ2|, and thus the color shift at the time of the front observation can be suppressed.

[0103] Thus, in the present embodiment, by making the azimuth angle φP1 of the first absorption axis 10P1A of the first polarizing plate 10P1 and the azimuth angle φ2 of the director 1312A of the liquid crystal molecules 132 on the second substrate 150 side in the no-voltage application state be a prescribed angle, and by making the azimuth angle φ2 of the director 1312A of the liquid crystal molecules 132 on the second substrate 150 side in the no-voltage application state and the azimuth angle φ1 of the director 1311A of the liquid crystal molecules 1311 on the first substrate 110 side be a prescribed angle, the function as the ECB mode imparted with some twist angle (5° or more and 20° or less) is exerted, the light shielding property at a low polar angle is maintained, and the color tone shift is suppressed. The viewing angle control liquid crystal panel 10 of the present embodiment is preferably used particularly in the vehicle market where the requirement criteria for privacy performance is strict and further improvement of the privacy performance (non-visual recognizability of images / movies) is required.

[0104] In the liquid crystal panel of the ECB mode having liquid crystal molecules having a positive dielectric anisotropy, there is a trade-off relationship between the light shielding angle and the retardation Re of the liquid crystal layer. Specifically, when Re of the liquid crystal layer in the no-voltage application state = 800 nm, the light shielding angle is about 45 degrees at the optimum voltage. In contrast, to obtain a light shielding angle of about 30°, Re = 1600 nm or so is required, and either the birefringence Δn or the cell thickness d of the liquid crystal layer must be increased. For example, when the cell thickness d is increased, Δn = 0.12 and d = 13 µm are required, and when the birefringence Δn is increased, Δn = 0.22 and d = 7 µm are required.

[0105] However, in either case of increasing the cell thickness d or increasing the birefringence Δn, there are problems in terms of productivity and reliability. In the case of increasing the cell thickness d, there are problems in terms of in-plane unevenness and yield (characteristic stability) due to thickening of the cell thickness. Further, in the case of making the birefringence Δn large, a high Δn can be achieved by using a stilbazole-based compound for the liquid crystal material, but there are problems such as unstable operation at low temperatures. On the other hand, the viewing angle control liquid crystal panel 10 of the present embodiment does not need to increase the cell thickness d or the birefringence Δn, and thus does not reduce the productivity and reliability, and further, can suppress unstable operation at low temperatures, and can sufficiently reduce the cut-off angle in the narrow viewing angle mode.

[0106] In the above-described Patent Document 1, a viewing angle control liquid crystal panel and a display liquid crystal panel are provided, the viewing angle control liquid crystal panel is composed of an ECB mode (parallel alignment state), and only the angle formed by the director of the liquid crystal molecules and the transmission axis of a polarizing plate sandwiching the display liquid crystal panel is 0° (parallel). At this time, the cut-off angle cannot be sufficiently reduced. On the other hand, in the viewing angle control liquid crystal panel 10 of the present embodiment, the cut-off angle can be sufficiently reduced in the narrow viewing angle mode, and color shift at the time of front observation can be suppressed.

[0107] The liquid crystal display device of the above-described Patent Document 2 is a double-cell type liquid crystal display device, which has a viewing angle control liquid crystal panel of an HAN mode, a display liquid crystal panel, and two layers of backlight cells for public mode and privacy mode, and can achieve a narrow viewing angle mode by setting the viewing angle control liquid crystal panel to an off state, setting the privacy mode backlight cell to an on state, and setting the public mode backlight cell to an off state, and can achieve a wide viewing angle mode by setting the viewing angle control liquid crystal panel to an on state, setting the public mode backlight cell to an on state, and setting the privacy mode backlight cell to an off state, and can switch between the narrow viewing angle mode and the wide viewing angle mode. In the liquid crystal display device of Patent Document 2, it is described that the cut-off angle is reduced, and the retardation (Re = Δn x d) of the liquid crystal layer needs to be increased, and it is difficult to balance the productivity. On the other hand, in the viewing angle control liquid crystal panel 10 of the present embodiment, the reduction in productivity can be suppressed, the cut-off angle can be sufficiently reduced in the narrow viewing angle mode, and color shift at the time of front observation can be suppressed.

[0108] The liquid crystal display device described in Non-Patent Document 1 is a dual-unit liquid crystal display device comprising a viewing angle control liquid crystal panel for VA mode, a display liquid crystal panel, and a venetian blind film. The viewing angle control liquid crystal panel has an ITO grid electrode on only one side of the substrate. In the liquid crystal display device of Non-Patent Document 1, when a voltage is applied to the grid electrode, the refractive index distribution within the liquid crystal cell is modulated by a lateral electric field, causing backlight to diffuse through the venetian blind film, thus achieving a common mode. Furthermore, when no voltage is applied, the backlight does not diffuse and leaks out to the display liquid crystal panel side as is, enabling a privacy mode. Thus, in the method of Non-Patent Document 1, since the light-shielding angle in privacy mode is determined by the venetian blind film, when using a venetian blind film with a small light-shielding angle, there is a problem that a sufficiently wide viewing angle cannot be obtained in the common mode. On the other hand, in the viewing angle control liquid crystal panel 10 of this embodiment, a sufficiently wide viewing angle can be obtained in the common mode, and the light-shielding angle is sufficiently reduced in the privacy mode, and color shift during frontal viewing can be suppressed.

[0109] The following is a detailed description of this embodiment.

[0110] like Figures 1-4 As shown, the liquid crystal panel 10 for viewing angle control in this embodiment preferably has a second polarizer 10P2 on the side of the second substrate 150 opposite to the liquid crystal layer 130. The second polarizer 10P2 has a second absorption axis 10P2A parallel to the first absorption axis 10P1A. By adopting this arrangement, the first polarizer 10P1 and the second polarizer 10P2 can be configured in parallel Nicole configuration. When the backlight is positioned on the back side of the liquid crystal panel 10 for viewing angle control, the backlight can be transmitted more effectively from the low polar angle side to the high polar angle side without voltage application.

[0111] More specifically, such as Figures 1-4 As shown, the liquid crystal panel 10 for viewing angle control in this embodiment comprises, from the viewing surface side to the back surface side, the following components in sequence: a first polarizing plate 10P1 having a first absorption axis 10P1A; a first substrate 110 having a first support substrate 111 and a first electrode 112; a first alignment film 120; a liquid crystal layer 130 containing liquid crystal molecules 131; a second alignment film 140; a second substrate 150 having a second electrode 152 and a second support substrate 151; and a second polarizing plate 10P2 having a second absorption axis 10P2A parallel to the first absorption axis 10P1A. The liquid crystal panel 10 for viewing angle control can control the transmission and non-transmission of light from the liquid crystal layer 130 by changing the voltage applied between the first electrode 112 and the second electrode 152, thereby causing a delay change in the liquid crystal layer 130.

[0112] The liquid crystal panel 10 for view angle control is a non-active liquid crystal panel of non-active drive. As with a general non-active liquid crystal panel, the first substrate 110 included in the liquid crystal panel 10 for view angle control includes the first electrode 112 as an entire-surface electrode covering the entire surface of the picture 50, and the second substrate 150 includes the second electrode 152 as an entire-surface electrode covering the entire surface of the picture 50. By adopting such a configuration, it is possible to switch between the public mode and the privacy mode over the entire picture 50.

[0113] As the first support substrate 111 and the second support substrate 151, for example, a glass substrate, a plastic substrate, or the like can be given. As a material of the glass substrate, for example, a float glass, a soda lime glass, or the like can be given. As a material of the plastic substrate, for example, a polyethylene terephthalate, a polybutylene terephthalate, a polyether sulfone, a polycarbonate, an alicyclic polyolefin, or the like can be given.

[0114] The first electrode 112 and the second electrode 152 can be transparent electrodes, and for example, 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.

[0115] The first alignment film 120 and the second alignment film 140 control the alignment azimuth of the liquid crystal molecules 131 in a state where no voltage is applied and the tilt angle of the liquid crystal molecules 131 in the state where no voltage is applied. The first alignment film 120 and the second alignment film 140 can be either a horizontal alignment film or a vertical alignment film, but from the viewpoint of improving the transmittance in the state where no voltage is applied, the first alignment film 120 and the second alignment film 140 are preferably a horizontal alignment film.

[0116] Here, a horizontal alignment film is an alignment film that, in a case where a substrate including the alignment film is used for a liquid crystal panel, exhibits an alignment regulating force that causes liquid crystal molecules in a liquid crystal layer to be aligned substantially horizontally with respect to the alignment film in a state where no voltage is applied to the liquid crystal layer. Further, a vertical alignment film is an alignment film that, in a case where a substrate including the alignment film is used for a liquid crystal panel, exhibits an alignment regulating force that causes liquid crystal molecules in a liquid crystal layer to be aligned substantially vertically with respect to the alignment film in a state where no voltage is applied to the liquid crystal layer.

[0117] By substantially horizontal is meant that the tilt angle is 0° or more and 10° or less, preferably 0° or more and 5° or less, and more preferably 0° or more and 2° or less. By substantially vertical is meant that the tilt angle is 83° or more and 90° or less, preferably 85° or more and 90° or less, and more preferably 87.5° or more and 88.0° or less.

[0118] Further, in the present specification, the "tilt angle" does not refer to the angle formed by the director of the liquid crystal molecules and the main surface of the substrate, but refers to the average of the angle formed by the director of the liquid crystal molecules in the thickness direction of the liquid crystal layer and the main surface of the substrate (the first substrate and the above-described second substrate), and the angle parallel to the main surface of the substrate is 0°, and the angle of the normal line of the main surface of the substrate is 90°. In particular, the tilt angle of the liquid crystal molecules in the state where no voltage is applied is also referred to as a pre-tilt angle. Further, the orientation azimuth of the liquid crystal molecules in the state where no voltage is applied is also referred to as an initial orientation azimuth. The tilt angle can be found by using a crystal rotation method, and for example, can be found using Axoscan (manufactured by Axometrics). Further, in the present embodiment, the director of the liquid crystal molecules is the direction of the orientation principal axis (the direction of the average alignment of the long axis of the molecules in the nematic liquid crystal). For example, in plan view, the director of the liquid crystal molecules in the state where no voltage is applied coincides with the orientation processing direction of the orientation film.

[0119] As the material of the first orientation film 120 and the second orientation film 140, a general material used in the field of liquid crystal panels, such as a polymer having a polyimide on the main chain, a polymer having a polyamic acid on the main chain, a polymer having a polysiloxane on the main chain, and the like, can be used. The first orientation film 120 and the second orientation film 140 can be formed by coating the orientation film material, and the above-described coating method is not particularly limited, and for example, flexographic printing, inkjet coating, or the like can be used.

[0120] The first orientation film 120 and the second orientation film 140 can be a photo-alignment film having a photo-functional group and on which photo-alignment processing is performed as orientation processing, can be a rubbing-alignment film on which rubbing processing is performed as orientation processing, or can be an alignment film on which no orientation processing is performed.

[0121] The liquid crystal layer 130 contains liquid crystal molecules 131. The orientation state of the liquid crystal molecules 131 changes in accordance with the voltage applied to the liquid crystal layer 130, and thereby the transmission amount of light is controlled. The dielectric anisotropy (Δε) of the liquid crystal molecules 131 is defined by the following formula (L). The liquid crystal molecules 131 preferably have a positive dielectric anisotropy. By adopting such a manner, it is possible to reduce the driving voltage. Further, it is possible to operate as a liquid crystal panel that is strong to the temperature environment outside (high reliability). In addition, the liquid crystal molecules having a positive dielectric anisotropy are referred to as positive liquid crystal molecules, and the liquid crystal molecules having a negative dielectric anisotropy are referred to as negative liquid crystal molecules. Further, the direction of the long axis of the liquid crystal molecules in the state where no voltage is applied is also referred to as the direction of the initial orientation of the liquid crystal molecules.

[0122] Δε = (dielectric constant in the long axis direction of the liquid crystal molecules) - (dielectric constant in the short axis direction of the liquid crystal molecules)... (L)

[0123] Further, since the liquid crystal molecules 131 have a positive dielectric anisotropy, the liquid crystal molecules 131 are in a parallel alignment in a state where no voltage is applied, and thus an ECB mode can be achieved. In the present specification, the parallel alignment refers to an alignment state in which the liquid crystal molecules 131 are horizontally aligned with respect to a substrate surface of a substrate that constitutes the viewing angle control liquid crystal panel 10 (for example, a substrate surface of at least one of the first substrate 110 and the second substrate 150) and the directions are also uniform. Further, in the present specification, the state where no voltage is applied (at the time when no voltage is applied) refers to a state in which no voltage above a threshold value of the liquid crystal molecules is applied in the liquid crystal layer, and for example, can be a state in which the same constant voltage is applied to the first electrode 112 and the second electrode 152, or a state in which a constant voltage is applied to one of the first electrode 112 and the second electrode 152 and a voltage lower than the threshold value of the liquid crystal molecules with respect to the constant voltage is applied to the other. Further, in the present specification, the state where a voltage is applied (at the time when a voltage is applied) refers to a state in which a voltage above the threshold value of the liquid crystal molecules is applied in the liquid crystal layer. The state where a voltage is applied refers to, for example, a state in which an optimal voltage is applied. Here, the optimal voltage is a voltage at which the retardation of the liquid crystal panel (for example, the ECB mode) satisfies λ / 2 [nm] at an angle of light blocking (for example, a range of a polar angle -40° to -30°).

[0124] Figure 5 is a perspective view that schematically shows a relationship between a director of a liquid crystal molecule in a state where no voltage is applied and an absorption axis of a polarizing plate in the viewing angle control liquid crystal panel according to the first embodiment. Figure 6 is a perspective view that schematically shows a relationship between a director of a liquid crystal molecule in a state where a voltage is applied and an absorption axis of a polarizing plate in the viewing angle control liquid crystal panel according to the first embodiment.

[0125] The viewing angle control liquid crystal panel 10 according to the present embodiment satisfies the above (Formula 2-1) or (Formula 2-2). Thus, in a state where no voltage is applied, as shown in Figure 5 , the angle formed by the director 131A of the liquid crystal molecules 131 and the first transmission axis 10P1B of the first polarizing plate 10P1 satisfies [90° - φ (φ1, φ2)] regardless of whether the case where the polar angle is 0° (a front direction) is observed or the case where a large polar angle (for example, a polar angle of -30°) is observed. Here, the director 131A of the liquid crystal molecules 131 refers to an average value of the directors of the liquid crystal molecules 131 included in the liquid crystal layer 130.

[0126] On the other hand, in a state where a voltage is applied, as shown in Figure 6As illustrated, the angle formed by the director 131A of the liquid crystal molecules 131 and the first transmission axis 10P1B of the first polarizing plate 10P1 satisfies 90° - φ (φ1, φ2) when viewed from the polar angle 0° (front direction), but the angle formed by the director 131A of the liquid crystal molecules 131 and the first transmission axis 10P1B of the first polarizing plate 10P1 becomes a different angle from that when viewed from the front direction depending on the tilt angle θ and the azimuthal angles φ1, φ2 of the liquid crystal molecules 131 when viewed from a large polar angle (for example, a polar angle of -30°).

[0127] Thus, in the present embodiment, by satisfying the above (Formula 2-1) or (Formula 2-2), the viewing angle control liquid crystal panel 10 functions as an asymmetric narrow viewing angle mode with respect to the horizontal direction (azimuthal angle 0° - 180°) in the central axis (polar angle 0°, that is, the front direction) in the voltage application state. In particular, in this narrow viewing angle mode, it is possible to reduce the shading angle to, for example, a polar angle of -40° - 30°, it is possible to sufficiently reduce the visually recognizable angle range (polar angle range), and it is possible to obtain a sufficient shading effect.

[0128] The viewing angle control liquid crystal panel 10 of the present embodiment satisfies the above (Formula 1). That is, the liquid crystal layer 130 contains liquid crystal molecules 131 that are twisted and oriented (twisted oriented) between the first substrate 110 and the second substrate 150. The liquid crystal molecules 131 are twisted and oriented from the first substrate 110 side to the second substrate 150 side. By adopting such a manner, it is possible to suppress the color shift generated between the wide viewing angle mode and the narrow viewing angle mode when viewed from the front.

[0129] The viewing angle control liquid crystal panel 10 more preferably satisfies the following (Formula 1-1). By adopting such a manner, it is possible to more effectively suppress the color shift when viewed from the front.

[0130] 5° ≤ | φ1 - φ2 | ≤ 15°... (Formula 1-1)

[0131] The twisted orientation of the liquid crystal molecules 131 can be achieved by, for example, adding a chiral agent to the liquid crystal material. There is no particular limitation on the chiral agent, and a conventionally known chiral agent can be used. As the chiral agent, for example, S-811 (manufactured by Merck Ltd.) or the like can be used. On the other hand, a small twist, for example, a twist orientation of 5° to 10° can be achieved without necessarily adding a chiral agent to the liquid crystal material, and without causing display defects such as disclination.

[0132] Preferably, the tilt angle of the liquid crystal molecules 131 is 1° or more and 5° or less in the no-voltage application state, and the tilt angle of the liquid crystal molecules 131 is 40° or more and 75° or less in the voltage application state. By adopting such a manner, it is possible to further reduce the angle (polar angle range) that can be visually recognized in the privacy mode. That is, it is possible to perform light shielding on the lower polar angle side. Here, in the present specification, with the direction perpendicular to the display surface of the liquid crystal panel as a reference, if closer to the perpendicular direction, it is set to the lower polar angle side, and if farther from the perpendicular direction, it is set to the higher polar angle side.

[0133] The birefringence Δn of the liquid crystal molecules 131 can be 0.08 or more and 0.24 or less. From the viewpoint of high reliability (high voltage holding ratio, wide operating temperature range), Δn is preferably 0.08 or more and 0.16 or less.

[0134] The thickness (cell thickness) d of the liquid crystal layer 130 is preferably 3 μm or more and 10 μm or less. By adopting such a manner, it is possible to accelerate the response speed of the liquid crystal molecules 131. In addition, it is possible to make the thickness of the viewing angle control liquid crystal panel 10 thinner. From the viewpoint of thinness, the thickness d of the liquid crystal layer 130 is more preferably 3 μm or more and 5 μm or less. From the viewpoint of yield, the thickness d of the liquid crystal layer 130 is more preferably 5 μm or more and 10 μm or less. If the thickness d of the liquid crystal layer 130 is 5 μm or more, it is difficult to make display unevenness when a foreign matter is mixed conspicuous, and it is possible to improve the yield.

[0135] The first electrode 112 and the second electrode 152 are electrodes in a full-surface shape, and the retardation Re of the liquid crystal layer 130 in the no-voltage application state is preferably 700 nm or more and 1200 nm or less. By adopting such a manner, it is possible to have a bright and wide viewing angle characteristic at the time of no-voltage application, on the other hand, it is possible to secure sufficient light shielding performance at the time of voltage application, and it is also possible to secure production stability. The retardation Re of the liquid crystal layer 130 is represented by the product of the birefringence (Δn) of the liquid crystal molecules and the thickness (d) of the liquid crystal layer.

[0136] Preferably, the first electrode 112 or the second electrode 152 is patterned in a pattern that is visually recognized from the tilt direction of the viewing angle control liquid crystal panel 10 in the case where the liquid crystal layer 130 is in the voltage application state. By adopting such a manner, when the viewing angle is narrow in the narrow viewing angle mode, the patterned portion is visually recognized by being made to transmit light, and therefore, in the case where the display panel is disposed on the back surface side of the viewing angle control liquid crystal panel 10, it is possible to make the content displayed on the display panel more difficult to visually recognize, and it is possible to improve the privacy performance.

[0137] The above pattern is, for example, a design pattern recognized by at least one design element among characters, figures, symbols, and patterns. As the above design element, a logo can be specifically given.

[0138] More preferably, a logo of the first electrode 112 or the second electrode 152 is patterned. By adopting such a manner, the logo is visually recognized at the time of the inclined observation in the narrow viewing angle mode. The size of each of the logos is not particularly limited, and for example, the area of each of the logos is preferably 5 mm 2 500 mm or more and 1000 mm or less 2 More preferably, 10 mm or more 2 100 m or more and 1000 m or less 2 or less.

[0139] Preferably, in the first electrode 112 or the second electrode 152, a pattern from which visual recognition is made from the inclined direction of the viewing angle control liquid crystal panel 10 in the case where the liquid crystal layer 130 is in the voltage application state is patterned, and the retardation Re of the liquid crystal layer 130 in the non-voltage application state is 700 nm or more and 900 nm or less. By adopting such a manner, bright and wide viewing angle characteristics are obtained in the non-voltage application (wide viewing angle mode), and sufficient light shielding performance is ensured in the voltage application (narrow viewing angle mode), and production stability is also ensured. Further, the patterned portion has no electrode, and thus no voltage is applied, and always becomes the wide viewing angle mode, and transmits light in both the front direction and the inclined direction. Therefore, at the time of the inclined observation in the narrow viewing angle mode, the patterned portion transmits light and is visually recognized, and thus, in the case where the display panel is disposed on the back side of the viewing angle control liquid crystal panel 10, the content displayed by the display panel is more difficult to visually recognize, and the patterned portion is prevented from being visually recognized at the time of the front observation in the narrow viewing angle mode.

[0140] The first polarizing plate 10P1 and the second polarizing plate 10P2 are each an absorption-type polarizing plate. As the first polarizing plate 10P1 and the second polarizing plate 10P2, for example, a polarizing plate (absorption-type polarizing plate) in which an anisotropic material such as an iodine complex (or a dye) is dyed and adsorbed to a polyvinyl alcohol (PVA) film and then stretched and oriented, or the like can be used.

[0141] The first polarizing plate 10P1 has a first absorption axis 10P1A and a first transmission axis 10P1B orthogonal to the first absorption axis 10P1A. The second polarizing plate 10P2 has a second absorption axis 10P2A and a second transmission axis 10P2B orthogonal to the second absorption axis 10P2A.

[0142] The second absorption axis 10P2A is parallel to the first absorption axis 10P1A. For example, the azimuth angles of the first absorption axis 10P1A and the second absorption axis 10P2A are set to 90°.

[0143] (Modified Example 1 of the First Embodiment)

[0144] Figure 7is a stereoscopic view of a viewing angle control liquid crystal panel of Modification 1 of the first embodiment. As shown in Figure 7 The viewing angle control liquid crystal panel 10 preferably further has a negative C-plate 160 having a retardation Rth in the thickness direction of 500 nm or more. By adopting such a configuration, it is possible to make the cut-off angle smaller in the narrow viewing angle mode. The negative C-plate 160 can be a single layer or a laminate of a plurality of layers. The configurations other than those described in this modification are the same as those of the first embodiment described above. Further, the same reference numerals are assigned to components having the same functions as those shown in the drawings of the first embodiment described above, and the description thereof is omitted.

[0145] The retardation Rth in the thickness direction of the negative C-plate 160 is more preferably 550 nm or more. The upper limit of the retardation Rth in the thickness direction of the negative C-plate 160 is not particularly limited, and is, for example, 1000 nm or less.

[0146] As the negative C-plate, for example, a stretched cyclo-olefin polymer film can be given.

[0147] (Modification 2 of the First Embodiment)

[0148] The viewing angle control liquid crystal panel 10 of the first embodiment described above is a non-active liquid crystal panel of non-active drive, but the viewing angle control liquid crystal panel 10 is not limited thereto, and can be, for example, an active matrix liquid crystal panel of active matrix drive. The configurations other than those described in this modification are the same as those of the first embodiment described above. Further, the same reference numerals are assigned to components having the same functions as those shown in the drawings of the first embodiment described above, and the description thereof is omitted.

[0149] Figure 8 is a stereoscopic view of a viewing angle control liquid crystal panel of Modification 2 of the first embodiment. Figure 8 The viewing angle control liquid crystal panel 10 of this modification shown in the drawing is an active matrix liquid crystal panel of active matrix drive. By adopting such a configuration, it is possible to partially switch the public mode and the privacy mode, instead of switching the entire screen 50.

[0150] The second substrate 150 provided in the viewing angle control liquid crystal panel 10 is configured in the same manner as a general active matrix liquid crystal panel, in which a grid is formed by the gate lines 153 and the source lines 154 orthogonal to each other, and a TFT (Thin Film Transistor) 155 as a switching element is provided near the intersection thereof. Further, a region surrounded by the gate lines 153 and the source lines 154 forms a pixel 11P, and a pixel electrode connected to the TFT 155 is provided as the second electrode 152 in each pixel 11P.

[0151] On the other hand, on the first substrate 110 opposite to the second substrate 150, a full-surface electrode, i.e., a common electrode, covering the entire surface of the picture 50 is provided as the first electrode 112.

[0152] The driving method of the viewing angle control liquid crystal panel 10 is not particularly limited, and for example, an active matrix driving method that is generally performed can be used. That is, the TFT 155 provided in each pixel is switched (turned on / off) via a gate driver. Then, in conjunction with this switching, a voltage is applied to the turned-on pixel via a source driver, and a charge is stored in the storage capacitor in each pixel via the drain bus of the TFT 155. Further, the pixel is held in the on state by the storage capacitor.

[0153] The gate line 153 is a wiring (usually a bus line connected to a plurality of gates) connected to the gate of the TFT 155, and a scan signal (a signal that controls the on state and the off state of the TFT) is applied to the gate of the connected TFT 155. The source line 154 is a wiring (usually a bus line connected to a plurality of sources) connected to the source of the TFT 155, and a data signal (for example, a video signal) is applied to the connected TFT 155. The gate line 153 and the source line 154 are usually configured in a linear shape in such a manner that one of them is arranged in a vertical direction across the array region in which the TFT 155 is arranged in a matrix shape, and the other is arranged in a horizontal direction across the array region.

[0154] The various wirings and electrodes that constitute the gate line 153, the source line 154, and the TFT 155 can be formed by sputtering or the like to form a single layer or multiple layers of a metal such as copper, titanium, aluminum, molybdenum, tungsten, or an alloy thereof, and then patterned by photolithography or the like. With respect to these various wirings and electrodes formed in the same layer, the manufacturing efficiency is improved by using the same material for each.

[0155] (Second Embodiment)

[0156] In the present embodiment, the features unique to the present embodiment will be mainly described, and the description of the contents repeated in the above-described first embodiment will be omitted. The present embodiment relates to a display device provided with the viewing angle control liquid crystal panel 10 and the display panel of the first embodiment.

[0157] Figure 9 is a cross-sectional view of the display device of the second embodiment. Figure 10 is a front view of the display device of the second embodiment. As Figure 9 and Figure 10As shown, the display device 1 of the present embodiment is provided with the viewing angle control liquid crystal panel 10 of the first embodiment and the liquid crystal display panel 20 as the above-described display panel. The display device 1 of the present embodiment is a viewing angle control liquid crystal display device of a double cell system. By adopting such a system, in a no-voltage application state in which no voltage above a threshold value is applied to the liquid crystal layer 130, the viewing angle control liquid crystal panel 10 functions as a wide viewing angle mode, and it is possible to visually recognize the image displayed on the liquid crystal display panel 20 with a wide viewing angle. Further, in a voltage application state in which a voltage above a threshold value is applied to the liquid crystal layer 130, the viewing angle control liquid crystal panel 10 functions as a narrow viewing angle mode that is asymmetric with respect to a central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°), and in particular, it is possible to reduce the shading angle to, for example, polar angle -40°-30°, it is possible to sufficiently reduce the angle range (polar angle range) in which the image can be visually recognized, and it is possible to obtain a sufficient shading effect. As a result, in the narrow viewing angle mode, it is possible to reduce the range (polar angle range) in which the image displayed on the liquid crystal display panel 20 can be visually confirmed. Moreover, when the display device 1 is observed from the front, it is possible to suppress color shift generated between the wide viewing angle mode and the narrow viewing angle mode.

[0158] The display device 1 of the present embodiment is provided with, in order from the back surface side toward the observation surface side, the backlight 30, the viewing angle control liquid crystal panel 10, and the liquid crystal display panel 20.

[0159] The viewing angle control liquid crystal panel 10 has, in order from the observation surface side toward the back surface side, the first polarizing plate 10P1, the first substrate 110, the first alignment film 120, the liquid crystal layer 130 (hereinafter also referred to as the first liquid crystal layer 130), the second alignment film 140, the second substrate 150, and the second polarizing plate 10P2.

[0160] The liquid crystal display panel 20 has, in order from the observation surface side toward the back surface side, the third polarizing plate 10P3, the third substrate 210, the third alignment film 220, the second liquid crystal layer 230, the fourth alignment film 240, the fourth substrate 250, and the fourth polarizing plate 10P4. The liquid crystal display panel 20 includes a plurality of pixels arranged in a matrix shape in the in-plane direction.

[0161] The third substrate 210 has, in order from the observation surface side toward the back surface side, the third support substrate 211, the color filter layer 212, and the black matrix layer 213. The third substrate 210 is also referred to as a color filter substrate.

[0162] As the third support substrate 211, there is no particular limitation, and for example, the same substrate as the first support substrate 111 and the second support substrate 151 can be cited.

[0163] The color filter layer 212 is composed, for example, of a red color filter, a green color filter, and a blue color filter. The red color filter, green color filter, and blue color filter are, for example, composed of a transparent resin containing pigment.

[0164] The black matrix layer 213 is arranged in a grid pattern, dividing the various color filters disposed on the color filter layer 212. The material of the black matrix layer is not particularly limited as long as it has light-shielding properties, but a resin material containing black pigment or a light-shielding metal material is preferred. The black matrix layer 213 is formed, for example, by photolithography, such as coating a photosensitive resin containing black pigment, exposing it, and developing it.

[0165] The fourth substrate 250 preferably includes a third electrode 252 and a fourth electrode 254. By employing this method, an IPS (In-Plane Switching) or FFS (Fringe Field Switching) liquid crystal display panel 20 can be realized, achieving a wide viewing angle even when the liquid crystal display panel 20 is used alone. In this embodiment, the case where the liquid crystal display panel 20 is in FFS mode will be described as an example.

[0166] like Figure 9 As shown, the fourth substrate 250, from the back side towards the viewing surface, sequentially includes a fourth support substrate 251, a third electrode 252 arranged for each of the aforementioned pixels, an insulating layer 253, and a fourth electrode 254 having a linear electrode portion 254a. That is, the fourth substrate 250 has an FFS-type electrode structure, wherein the third electrode 252 and the fourth electrode 254 are stacked with the insulating layer 253 in between. The fourth substrate 250 is also referred to as an active matrix substrate.

[0167] Furthermore, the fourth substrate 250 has multiple gate lines extending parallel to each other, and multiple source lines extending parallel to each other in the direction intersecting with each gate line, separated by an insulating film. The multiple gate lines and multiple source lines are formed as a whole in a lattice shape. TFTs are disposed at the intersections of the gate lines and source lines as switching elements.

[0168] In addition, in this embodiment, a liquid crystal display panel 20 with an FFS type electrode structure is used as an example for explanation, but this embodiment can also be applied to an IPS type electrode structure. In the IPS type electrode structure, the third electrode 252 and the fourth electrode 254 are comb electrodes. The third electrode 252 and the fourth electrode 254, which are comb electrodes, are disposed on the same electrode layer in a manner in which the comb teeth interlock with each other.

[0169] The fourth support substrate 251 provided as the fourth substrate 250 is not particularly limited, and for example, the same substrate as the first support substrate 111 and the second support substrate 151 can be given.

[0170] The third electrode 252 and the fourth electrode 254 are arranged per pixel. The third electrode 252 is preferably a planar electrode. In the present specification, the "planar electrode" refers to an electrode that has no slit or opening when viewed from above. The third electrode 252 preferably overlaps at least the linear electrode portion 254a provided in the fourth electrode 254 when viewed from above.

[0171] The fourth electrode 254 is arranged across multiple pixels in an electrically continuous manner. The fourth electrode 254 has a linear electrode portion 254a. As the planar shape of the fourth electrode 254, a structure in which both ends of a plurality of linear electrode portions 254a are closed can be given. An opening 254b surrounded by the electrode portion can also be provided in the fourth electrode 254.

[0172] The plurality of fourth electrodes 254 arranged per pixel can also be electrically connected to each other, a constant voltage common to the above-described plurality of pixels is applied, and the plurality of third electrodes 252 arranged per pixel are respectively electrically connected to the corresponding source lines via the semiconductor layer provided in the TFT, and different voltages are applied to each pixel according to the image signal. Alternatively, the plurality of fourth electrodes 254 can be respectively electrically connected to the corresponding source lines via the semiconductor layer provided in the TFT, and different voltages are applied to each pixel according to the image signal, and the plurality of third electrodes 252 are electrically connected to each other, a constant voltage common to the above-described plurality of pixels is applied.

[0173] The same electrodes as the first electrode 112 and the second electrode 152 can be given as the third electrode 252 and the fourth electrode 254.

[0174] As the insulating layer 253, an inorganic insulating film, an organic insulating film, or the like can be given. As the inorganic insulating film, for example, an inorganic film (relative dielectric constant ε = 5 to 7) such as silicon nitride (SiNx) or silicon oxide (SiO2), or a laminated film thereof can be used. As the organic insulating film, for example, an organic film such as an acrylic resin, a polyimide resin, a novolak resin, or a laminate thereof can be used.

[0175] The third alignment film 220 and the fourth alignment film 240 control the alignment potential of the liquid crystal molecules 231 in the no-voltage application state and the tilt angle of the liquid crystal molecules 231 in the no-voltage application state. The third alignment film 220 and the fourth alignment film 240 can be either a horizontal alignment film or a vertical alignment film, but from the viewpoint of adjusting the in-plane liquid crystal retardation and obtaining sufficient white brightness, the third alignment film 220 and the fourth alignment film 240 are preferably a horizontal alignment film.

[0176] The third alignment film 220 and the fourth alignment film 240 can be either a rubbing alignment film or a photo-alignment film. The third alignment film 220 and the fourth alignment film 240 contain, for example, an alignment film polymer having a polyimide in a main chain, a polymer having a polyamide acid in a main chain, a polymer having a polysiloxane in a main chain, or the like. The third alignment film 220 and the fourth alignment film 240 can be formed, for example, by applying an alignment film material containing the above-described alignment film polymer to the third substrate 210 and the fourth substrate 250, and the application method is not particularly limited, and for example, flexographic printing, inkjet application, or the like can be used.

[0177] The second liquid crystal layer 230 contains liquid crystal molecules 231, and the alignment state of the liquid crystal molecules 231 changes depending on the voltage applied to the second liquid crystal layer 230, thereby controlling the amount of light transmission. The dielectric anisotropy (Δε) of the liquid crystal molecules defined by the above formula (L) can have a positive value or a negative value, but it is preferable that the dielectric anisotropy have a positive value.

[0178] The third polarizing plate 10P3 and the fourth polarizing plate 10P4 are both absorption-type polarizing plates. As the third polarizing plate 10P3 and the fourth polarizing plate 10P4, for example, a polarizing sheet (absorption-type polarizing plate) in which an anisotropic material such as an iodine complex (or a dye) is dyed and adsorbed to a polyvinyl alcohol (PVA) film and then stretched and aligned, or the like can be used.

[0179] The third polarizing plate 10P3 has a third absorption axis 10P3A and a third transmission axis orthogonal to the third absorption axis 10P3A. The fourth polarizing plate 10P4 has a fourth absorption axis 10P4A and a fourth transmission axis orthogonal to the fourth absorption axis 10P4A.

[0180] Preferably, the liquid crystal display panel 20 has, in order, the third polarizing plate 10P3 having the third absorption axis 10P3A, the second liquid crystal layer 230, the fourth polarizing plate 10P4 having the fourth absorption axis 10P4A orthogonal to the third absorption axis 10P3A, and of the third polarizing plate 10P3 and the fourth polarizing plate 10P4, the fourth absorption axis 10P4A of the polarizing plate closer to the viewing angle control liquid crystal panel 10 side, that is, the fourth polarizing plate 10P4, is parallel to the first absorption axis 10P1A. By adopting such a configuration, black display can be achieved in a no-voltage application state.

[0181] In the present embodiment, for example, the azimuth angle φP1 of the first absorption axis 10P1A, the azimuth angle of the second absorption axis 10P2A, and the azimuth angle of the fourth absorption axis 10P4A are set to 90°, and the azimuth angle of the third absorption axis 10P3A is set to 0°.

[0182] As the backlight 30, a backlight commonly used in the field of liquid crystal display devices can be used. The backlight 30 is disposed on the back surface side of the viewing angle control liquid crystal panel 10, and can be either a direct type or an edge type, as long as light generated by the backlight 30 can be emitted to the observation surface side. The type of light source of the backlight 30 is not particularly limited, and examples include a light emitting diode (LED), a cold cathode fluorescent lamp (CCFL), and the like.

[0183] The backlight 30 can also be a backlight provided with a louver film in order to improve directivity. Further, it is preferable that the backlight 30 have two light guide plates, one of which functions as a wide viewing angle mode and the other of which functions as a narrow viewing angle mode. More specifically, for example, the backlight 30 can have a light guide plate laminate in which a diffusion light guide plate and a non-diffusion light guide plate are overlaid, and by independently controlling LEDs disposed at the end portions of the respective light guide plates, it is possible to switch between a public mode and a privacy mode as the backlight.

[0184] The liquid crystal display panel 20 can also have a viewing angle expansion film (phase difference film) on the observation surface side of the third substrate 210 or on the back surface side of the fourth substrate 250. As the viewing angle expansion film, for example, a SAM film having a wedge-shaped inclined surface structure that diffuses straight-ahead light in all directions, or the like, can be cited.

[0185] (Variation 1 of the Second Embodiment)

[0186] Figure 11 is a cross-sectional schematic view of a display device of Variation 1 of the second embodiment. Figure 12 is a front surface schematic view of the display device of Variation 1 of the second embodiment. The liquid crystal display panel 20 provided in the display device 1 of the above-described second embodiment is disposed on the observation surface side of the viewing angle control liquid crystal panel 10, but the disposition of the liquid crystal display panel 20 is not limited thereto, and as shown in Figure 11 and Figure 12 shown, the liquid crystal display panel 20 can also be disposed on the back surface side of the viewing angle control liquid crystal panel 10. With such a configuration, the same effects as the second embodiment can also be obtained.

[0187] In the liquid crystal display panel 20 in this variation, the third absorption axis 10P3A of the third polarizing plate 10P3, which is the polarizing plate on the side closer to the viewing angle control liquid crystal panel 10, among the third and fourth polarizing plates 10P3 and 10P4, is preferably parallel to the first absorption axis 10P1A. By adopting such a manner, black display can be achieved in a no-voltage application state.

[0188] In the present modification example, for example, the azimuth angle φP1 of the first absorption axis 10P1A, the azimuth angle of the second absorption axis 10P2A, and the azimuth angle of the third absorption axis 10P3A are set to 0°, and the azimuth angle of the fourth absorption axis 10P4A is set to 90°.

[0189] (Modification Example 2 of Second Embodiment)

[0190] In the above-described second embodiment, the liquid crystal display panel 20 is used as the display panel, but the display panel is not particularly limited as long as it is of a light-emitting type, and for example, it can be an organic EL (Electro Luminescence) display panel, an inorganic EL display panel, a micro LED display panel, or a QLED (Quantum dot Light emitting diode) display panel. In the case where the display panel is an organic EL display panel, an inorganic EL display panel, a micro LED display panel, or a QLED display panel, the liquid crystal panel 10 for viewing angle control is disposed on the observation surface side of the display panel, and the display device 1 does not have a backlight. As a method of QLED, for example, a liquid crystal type is used, a blue LED is used in a backlight light source, and by using wavelength conversion based on quantum dots (conversion from blue light to green light, conversion from blue light to red light, and transmission of blue light as it is), more rich color reproduction and low power consumption can be achieved compared to conventional liquid crystal panels.

[0191] As the second polarizing plate 10P2, an absorption type can also be used, but for example, since OLED (organic light-emitting diode) light used in an organic EL display panel is unpolarized light, by using a reflection type (configuration is a linear polarizing plate / reflection type polarizing plate), light recycling efficiency can also be improved, and brightness can be improved.

[0192] (Modification Example 3 of Second Embodiment)

[0193] In the above-described second embodiment, the liquid crystal display panel 20 can also be a vertical pixel arrangement. Figure 32 is a plan view of a third substrate provided in the liquid crystal display panel of the display device of Modification Example 3 of the second embodiment. Figure 33 is a plan view of a fourth substrate provided in the liquid crystal display panel of the display device of Modification Example 3 of the second embodiment.

[0194] As Figure 9 , Figure 32 and Figure 33As shown, the liquid crystal display panel 20 as the display panel has a third substrate 210, a second liquid crystal layer 230, and a fourth substrate 250. The third substrate 210 has color filters 212C of a plurality of colors, and the fourth substrate 250 has third electrodes 252 or fourth electrodes 254 as pixel electrodes 250P. The color filters 212C of the plurality of colors and the pixel electrodes 250P are each in a long strip shape, and the long side directions of the color filters 212C of the plurality of colors and the pixel electrodes 250P are each arranged along the up-down direction of the liquid crystal display panel 20. In this way, by arranging the long side directions of the color filters 212C of the plurality of colors and the pixel electrodes 250P in the vertical pixel arrangement along the up-down direction of the liquid crystal display panel 20, it is possible to suppress an increase in the frame width of the edges on the left and right of the liquid crystal display panel 20 for arranging modules.

[0195] In the present specification, the upper side of the liquid crystal display panel 20 refers to an azimuth angle of 90° of the liquid crystal display panel 20, the lower side of the liquid crystal display panel 20 refers to an azimuth angle of 270° of the liquid crystal display panel 20, the right side of the liquid crystal display panel 20 refers to an azimuth angle of 0° of the liquid crystal display panel 20, and the left side of the liquid crystal display panel 20 refers to an azimuth angle of 180° of the liquid crystal display panel 20. That is, the up-down direction of the liquid crystal display panel 20 is the azimuth angle 90°-270° direction of the liquid crystal display panel 20, and the left-right direction of the liquid crystal display panel 20 is the azimuth angle 0°-180° direction of the liquid crystal display panel 20, that is, the above-described horizontal direction. Furthermore, in the present specification, the azimuth 0° is used equally to the azimuth angle 0°, the azimuth 90° is used equally to the azimuth angle 90°, the azimuth 180° is used equally to the azimuth angle 180°, the azimuth 270° is used equally to the azimuth angle 270°, and the azimuth 360° is used equally to the azimuth angle 360°. That is, the angle indicated after the azimuth indicates the azimuth angle.

[0196] The fourth substrate 250 is provided so that the gate lines 256 and the source lines 257 intersect each other to form a lattice, and a TFT as a switching element is provided near the intersection. Furthermore, the area surrounded by the gate lines 256 and the source lines 257 forms a pixel 21P, and in each pixel 21P, a pixel electrode 250P as the third electrode 252 or the fourth electrode 254 is provided connected to the TFT. The fourth substrate 250 is also referred to as a TFT substrate.

[0197] Each pixel electrode 250P is in a long strip shape, and the long side direction of each pixel electrode 250P is arranged along the up-down direction of the liquid crystal display panel 20. That is, each pixel electrode 250P is arranged so as to extend along the up-down direction of the liquid crystal display panel 20.

[0198] Each of the pixels 21P is in a long strip shape, and the long side direction of each of the pixels 21P is arranged along the up-down direction of the liquid crystal display panel 20. That is, each of the pixels 21P is arranged so as to extend along the up-down direction of the liquid crystal display panel 20.

[0199] The length of the long side direction (up-down direction) of each of the pixels 21P is 130 µm or more and 170 µm or less, preferably 140 µm or more and 160 µm or less, and for example, 150 µm. The length of the short side direction (left-right direction) of each of the pixels 21P is 30 µm or more and 70 µm or less, preferably 40 µm or more and 60 µm or less, and for example, 50 µm.

[0200] The slit 250PS is provided on the pixel electrode 250P along the long side direction (up-down direction) of the pixel electrode 250P. The liquid crystal molecules 231 included in the second liquid crystal layer 230 are oriented along the slit 250PS in a no-voltage application state.

[0201] The third substrate 210 includes a color filter layer 212 including color filters 212C of a plurality of different colors and a black matrix layer 213. The color filters 212C of the plurality of different colors include, for example, a red color filter 212CR, a green color filter 212CG, and a blue color filter 212CB, and any of the color filters 212C is arranged in each of the pixels 21P. The third substrate 210 is also referred to as a color filter substrate.

[0202] The red color filter 212CR, the green color filter 212CG, and the blue color filter 212CB are each in a long strip shape, and the long side direction of each of the color filters 212C is arranged along the up-down direction of the liquid crystal display panel 20. That is, each of the red color filter 212CR, the green color filter 212CG, and the blue color filter 212CB is arranged so as to extend along the up-down direction of the liquid crystal display panel 20.

[0203] The third substrate 210 includes the black matrix layer 213 provided with a plurality of opening portions 213S corresponding to the color filters 212C of the plurality of different colors, respectively. The width LA in the up-down direction of the liquid crystal display panel 20 of each of the opening portions 213S is 80 µm or more and 140 µm or less, and the width WA in the left-right direction of the liquid crystal display panel 20 of each of the opening portions 213S is 80 µm or less.

[0204] The vertical width LA (also called LA1) of the opening 213S corresponding to the blue color filter 212CB in the liquid crystal display panel 20 is larger than the vertical width LA (also called LA2) of the opening 213S corresponding to the green color filter 212CG and the opening 213S corresponding to the red color filter 212CR in the liquid crystal display panel 20. For example, the vertical width LA (LA1) of the opening 213S corresponding to the blue color filter 212CB in the liquid crystal display panel 20 is 120μm, and the vertical width LA (LA2) of the opening 213S corresponding to the green color filter 212CG and the opening 213S corresponding to the red color filter 212CR in the liquid crystal display panel 20 is 100μm.

[0205] The width WA of the opening 213S corresponding to the blue color filter 212CB, the opening 213S corresponding to the green color filter 212CG, and the opening 213S corresponding to the red color filter 212CR in the left-right direction of the liquid crystal display panel 20 is, for example, 40μm.

[0206] (Modification 4 of the second embodiment)

[0207] In the second embodiment described above, the liquid crystal display panel 20 may also have a horizontal pixel arrangement. Figure 34 This is a plan view of the third substrate included in the liquid crystal display panel of the display device of the second embodiment, variant 4. Figure 35 This is a plan view of the fourth substrate included in the liquid crystal display panel of the display device of the second embodiment, variant 4.

[0208] like Figure 9 , Figure 34 as well as Figure 35 As shown, the liquid crystal display panel 20, which is the above-mentioned display panel, has a third substrate 210, a second liquid crystal layer 230, and a fourth substrate 250. The third substrate 210 has a multi-color filter 212C, and the fourth substrate 250 has a third electrode 252 or a fourth electrode 254 as a pixel electrode 250P. The multi-color filter 212C and the pixel electrode 250P are both elongated, and the long side of the multi-color filter 212C and the pixel electrode 250P are respectively arranged along the left and right directions of the liquid crystal display panel 20.

[0209] Here, in the vertical pixel arrangement shown in the modified example 3 of the second embodiment described above, the spacing of the polarized light transmitted through the fourth polarizing plate 10P4 in the left-right direction of the wiring provided on the fourth substrate 250, i.e. Figure 33the distance between the source lines 257 in the display device of 12.3 inches / 170 ppi, for example, is about 50 µm, Figure 32 The width of the opening portion 213S of the black matrix layer 213 in the lateral direction (short side direction) is about 40 µm, for example, and light diffraction is likely to occur in this direction, and the light blocking property is likely to decrease.

[0210] On the other hand, in the present modification example, the long side direction of the color filter 212C and the pixel electrode 250P of each color is arranged in the lateral pixel arrangement in which the arrangement direction is along the lateral direction of the liquid crystal display panel 20, and the distance between the wirings provided in the fourth substrate 250 in the lateral direction and the width of the opening portion 213S of the black matrix layer 213 in the lateral direction are increased, and light diffraction is suppressed compared to the longitudinal pixel arrangement. As a result, the light blocking property is improved compared to the longitudinal pixel arrangement, and the privacy performance is improved.

[0211] For example, in the display device of 12.3 inches / 170 ppi, the distance between the wirings provided in the fourth substrate 250 in the lateral direction, that is, the distance between the source lines 257 in the display device of 12.3 inches / 170 ppi, for example, is about 50 µm, Figure 35 the distance between the gate lines 256 in the display device of 12.3 inches / 170 ppi is extended to about 150 µm, and further, Figure 34 the width of the opening portion 213S of the black matrix layer 213 in the lateral direction (long side direction) is extended to 100 µm or more and 120 µm or less. As a result, in the lateral pixel arrangement, light diffraction is less likely to occur compared to the longitudinal pixel arrangement, and the light blocking property is improved. According to the above, in the present modification example of the lateral pixel arrangement, the privacy performance is improved compared to the modification example 3 of the above-described second embodiment of the longitudinal pixel arrangement. In addition, in a display device having a resolution lower than the above (for example, < 100 ppi), the pixel shape is not necessarily a horizontally long rectangular shape, and can be a square shape as long as the width WB in the lateral direction is 80 µm or more and 140 µm or less.

[0212] In the display device of 12.3 inches / 170 ppi, for example, the privacy performance (light blocking performance) in the horizontal direction of the screen (azimuth angle 0°-180°), polar angle -30° is improved by about 2 times compared to the longitudinal pixel arrangement. That is, in the horizontal direction of the screen (azimuth angle 0°-180°), polar angle -30°, the luminance of the lateral pixel arrangement is about half compared to the longitudinal pixel arrangement.

[0213] The lateral pixel arrangement is an arrangement in which the liquid crystal display panel 20 of the longitudinal pixel arrangement shown in the above-described modification example is rotated by 90°. The third absorption axis 10P3A of the third polarizing plate 10P3 and the fourth absorption axis 10P4A of the fourth polarizing plate 10P4 are not changed, and only the liquid crystal display panel 20 is rotated.

[0214] In the present modification, it is possible to suppress an increase in the frame width for arranging the module on the upper side and the lower side of the liquid crystal display panel 20. However, since the number of gate lines 256 provided in the left-right direction of the liquid crystal display panel is increased, the frame width for arranging the module can possibly increase in at least one of the left side and the right side of the liquid crystal display panel 20.

[0215] In addition, in either of the configurations of Modification 3 of the second embodiment and the present Modification 4, since the liquid crystal display panel 20 is of the IPS mode or the FFS mode, the display device 1 has a wide enough viewing angle in the common mode.

[0216] The fourth substrate 250 is provided so that the gate lines 256 and the source lines 257 orthogonal to each other form a lattice, and TFTs as switching elements are provided near the intersections thereof. Further, the regions surrounded by the gate lines 256 and the source lines 257 form the pixels 21P, and the pixel electrodes 250P connected to the TFTs are provided as the third electrodes 252 or the fourth electrodes 254 in each of the pixels 21P. The fourth substrate 250 is also referred to as a TFT substrate. In the present modification, the gate lines 256 are arranged in the up-down direction and the source lines 257 are arranged in the left-right direction, but the arrangement of the gate lines 256 and the source lines 257 is not limited thereto, and the gate lines 256 can be arranged in the left-right direction and the source lines 257 can be arranged in the up-down direction.

[0217] Each of the pixel electrodes 250P has a long strip shape, and the long side direction of each of the pixel electrodes 250P is arranged in the left-right direction of the liquid crystal display panel 20. That is, each of the pixel electrodes 250P is arranged so as to extend in the left-right direction of the liquid crystal display panel 20.

[0218] Each of the pixels 21P has a long strip shape, and the long side direction of each of the pixels 21P is arranged in the left-right direction of the liquid crystal display panel 20. That is, each of the pixels 21P is arranged so as to extend in the left-right direction of the liquid crystal display panel 20.

[0219] The length of the long side direction (the left-right direction) of each of the pixels 21P is 130 µm or more and 170 µm or less, preferably 140 µm or more and 160 µm or less, and for example, 150 µm. The length of the short side direction (the up-down direction) of each of the pixels 21P is 30 µm or more and 70 µm or less, preferably 40 µm or more and 60 µm or less, and for example, 50 µm.

[0220] A slit 250PS is provided on the pixel electrode 250P in the long side direction (the left-right direction) of the pixel electrode 250P. The liquid crystal molecules 231 included in the second liquid crystal layer 230 are aligned along the slit 250PS in a voltage non-application state.

[0221] The third substrate 210 includes a color filter layer 212 including color filters 212C of different colors and a black matrix layer 213. The color filters 212C of different colors include, for example, red color filters 212CR, green color filters 212CG, and blue color filters 212CB, and any color filter 212C is arranged in each pixel 21P. The third substrate 210 is also referred to as a color filter substrate.

[0222] The red color filters 212CR, the green color filters 212CG, and the blue color filters 212CB are each in a long strip shape, and each long side direction is arranged along the left-right direction of the liquid crystal display panel 20. That is, the red color filters 212CR, the green color filters 212CG, and the blue color filters 212CB are each provided so as to extend in the left-right direction of the liquid crystal display panel 20.

[0223] Preferably, the third substrate 210 includes the black matrix layer 213 provided with a plurality of opening portions 213S corresponding to the color filters 212C of different colors, the width WB of each of the plurality of opening portions 213S in the left-right direction of the liquid crystal display panel 20 is 80 µm or more and 140 µm or less, and the width LB of each of the plurality of opening portions 213S in the up-down direction of the liquid crystal display panel 20 is 80 µm or less. By adopting such a configuration, light diffraction due to the black matrix layer 213 can be effectively suppressed. As a result, the light shielding property can be improved, and the privacy performance can be improved.

[0224] The width WB (also referred to as WB1) of the opening portion 213S provided corresponding to the blue color filter 212CB in the left-right direction of the liquid crystal display panel 20 is larger than the width WB (also referred to as WB2) of the opening portion 213S provided corresponding to the green color filter 212CG and the red color filter 212CR in the left-right direction of the liquid crystal display panel 20. The width WB (WB1) of the opening portion 213S provided corresponding to the blue color filter 212CB in the left-right direction of the liquid crystal display panel 20 is, for example, 120 µm, and the width WB (WB2) of the opening portion 213S provided corresponding to the green color filter 212CG and the red color filter 212CR in the left-right direction of the liquid crystal display panel 20 is, for example, 100 µm.

[0225] The width LB in the up-and-down direction of the liquid crystal display panel 20 of the opening portion 213S provided in correspondence with the blue color filter 212CB, the opening portion 213S provided in correspondence with the green color filter 212CG, and the opening portion 213S provided in correspondence with the red color filter 212CR is, for example, 40 μm.

[0226] (5th Modification of the 2nd Embodiment)

[0227] As the backlight 30, the backlight cited in the present modification can also be used. Figure 36 is a perspective view of the backlight provided in the display device of the 5th modification of the 2nd embodiment. As shown in Figure 36 the backlight 30 of the present modification is provided in order from the back surface side toward the observation surface side with: a reflection plate 35; a general light guide plate 36 having LEDs 36L at the end portions (sides); a prism sheet 37; a louver film 38; and a common light guide plate 39 having LEDs 39L at the end portions (sides). The backlight composed of the reflection plate 35, the general light guide plate 36 having LEDs 36L at the end portions (sides), and the prism sheet 37 is also referred to as a general backlight 30N. The backlight in which LEDs are arranged at the end portions of two layers as in the present modification is also referred to as a backlight composed of two layers.

[0228] The reflection plate 35 is an optical film having a reflectance of 98% or more, and is, for example, ESR manufactured by 3M Company. The general light guide plate 36 has the same configuration as a general light guide plate, and has a function of guiding light from the LEDs 36L in the plane of the general light guide plate 36. The prism sheet 37 has the same configuration as a general prism sheet, and, for example, BEF series (brightness enhancement film) manufactured by 3M Company can be used. The louver film 38 has a function of reducing the brightness of oblique light in the left-and-right direction (horizontal direction), i.e., the azimuthal angle of 0° to 180°. The louver film 38 can also be a louver film that shields oblique light left-and-right symmetrically with respect to the left-and-right direction. The common light guide plate 39 has a function of diffusing light from the LEDs 39L by using a structure body engraved on the common light guide plate 39, and causing the diffused light to exit. Further, the common light guide plate 39 includes microparticles and an acrylic resin that diffuse incident light at a wide viewing angle. As the acrylic resin, polymethyl methacrylate (PMMA) is particularly preferable.

[0229] In the combination of the general backlight 30N and the louver film 38, the microparticles contained in the common light guide plate 39 do not cause dispersion of incident light because the optical path is short, and thus a narrow viewing angle is obtained.

[0230] Figure 37 is a cross-sectional view for explaining a case in which the LEDs provided at the general light guide plate and the LEDs provided at the common light guide plate in the backlight provided in the display device of the 5th modification of the 2nd embodiment are in an on state.Figure 38 This is a cross-sectional schematic diagram illustrating the case where the LEDs provided on the conventional light guide plate and the LEDs provided on the common light guide plate are in the off state in the backlight of the display device of the modified example 5 of the second embodiment. Figure 39 This is a cross-sectional schematic diagram illustrating the case where the LEDs provided on the conventional light guide plate are in an off state and the LEDs provided on the common light guide plate are in an on state in the backlight of the display device of the modified example 5 of the second embodiment.

[0231] Figure 37 As shown, when both LED36L in the conventional light guide plate 36 and LED39L in the common light guide plate 39 are in the on state, that is, when both LED36L and LED39L are lit at the same time, the backlight 30 functions as a wide viewing angle mode.

[0232] like Figure 38 As shown, when the LED 36L on the conventional light guide plate 36 is in the on state and the LED 39L on the common light guide plate 39 is in the off state, that is, when the LED 36L is lit and the LED 39L is off, the backlight 30 functions as a narrow viewing angle mode.

[0233] In addition, with Figure 38 Compared to the narrow viewing angle mode shown, the front brightness is reduced, but as Figure 39 As shown, when the LED36L on the conventional light guide plate 36 is in the off state and the LED39L on the common light guide plate 39 is in the on state, that is, when the LED36L is off and the LED39L is lit, the backlight 30 also functions as a narrow viewing angle mode.

[0234] (Modification 6 of the second embodiment)

[0235] Figure 40 This is a perspective view of the backlight provided in the display device of Modification 6 of the second embodiment. Based on the configuration of Modification 5 of the second embodiment described above, as... Figure 40 As shown, a venetian blind film 381 can also be provided directly above the public light guide plate 39 to reduce the brightness of oblique light in the vertical direction, i.e., in the azimuth angle direction of 90°-270°. By providing the venetian blind film 381 as in this modified example, when the display device 1 is used for automotive purposes, it is possible to prevent reflection from the windshield. A conventional venetian blind film can be used on the venetian blind film 381.

[0236] The following examples and comparative examples illustrate the effects of the present invention, but the present invention is not limited to these examples.

[0237] (Example 1)

[0238] For the viewing angle control liquid crystal panel 10 of Embodiment 1 having the same configuration as the first embodiment described above, the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer 130, and the shielding angle with respect to the retardation of the first liquid crystal layer 130 were calculated by simulation.

[0239] The color difference was calculated by using the LCD master 2D to calculate the voltage dependence of the transmittance (vertical axis) with respect to the polar angle (horizontal axis) in the horizontal direction (azimuth angle 0°-180°) of the viewing angle control liquid crystal panel. That is, according to the calculation results, the color coordinates (x, y) of the front surface at each voltage (for example, 0 V and 5.5 V (optimum voltage)) were obtained, and thus they were converted into the color coordinates (u', v') of the front surface. Specifically, the color coordinates (u'_public, v'_public) of the front surface at the wide viewing angle mode (0 V) and the color coordinates (u'_privacy, v'_privacy) of the front surface at the narrow viewing angle mode (5.5 V) were converted. Further, the color difference (u'v' color difference) was calculated as the difference between the color coordinates (u'_public, v'_public) of the front surface at the wide viewing angle mode (0 V) and the color coordinates (u'_privacy, v'_privacy) of the front surface at the narrow viewing angle mode (5.5 V) as shown in the following formula.

[0240] u'v' color difference = V { (u'_public - u'_privacy) 2 + (v'_public - v'_privacy) 2}

[0241] Figure 13A One example of the measurement results of the shielding angle. The shielding angle was calculated by using the LCD master 2D to calculate the voltage dependence of the transmittance (vertical axis) with respect to the polar angle (horizontal axis) in the horizontal direction (azimuth angle 0°-180°) of the viewing angle control liquid crystal panel. One example of the measurement results is shown in FIG. 8. Figure 13A In FIG. 8, Figure 13A the voltage of 0 V functions as the wide viewing angle mode, and the voltage of 5.5 V (optimum voltage) functions as the narrow viewing angle mode. As Figure 13A indicated in FIG. 8, in the narrow viewing angle mode in which the optimum voltage is applied, the negative polar angle at which the transmittance becomes the lowest is the shielding angle. In addition, Figure 13A is the measurement results of the shielding angle of the liquid crystal panel having the same configuration as that of Embodiment 4 described later.

[0242] In Embodiment 1, the azimuth angle φP1 of the first absorption axis 10P1A of the first polarizing plate 10P1 was 90°, the azimuth angle of the second absorption axis 10P2A of the second polarizing plate 10P2 was 90°, the azimuth angle φ1 of the director 1311A of the liquid crystal molecules 1311 on the first substrate 110 side in the no-voltage-applied state was 90°, and the azimuth angle φ2 of the director 1312A of the liquid crystal molecules 1312 on the second substrate 150 side was 75°. That is, the azimuth angle φ1 of the director 1311A of the liquid crystal molecules 1311 on the first substrate 110 side and the azimuth angle φ2 of the director 1312A of the liquid crystal molecules 1312 on the second substrate 150 side satisfy φ1 > φ2, and the liquid crystal molecules 131 are twisted within the liquid crystal layer 130. In addition, in the embodiments and comparative examples of the present specification, the azimuth angles φ1 and φ2 of the directors of the liquid crystal molecules are determined depending on the orientation processing direction of the alignment film.

[0243] In Embodiment 1, the angle formed by the first absorption axis 10P1A and the second absorption axis 10P2A and the director 1312A of the liquid crystal molecules 1312 on the second substrate 150 side in the no-voltage-applied state was 15°, and the first absorption axis 10P1A and the second absorption axis 10P2A were parallel to the director 1311A of the liquid crystal molecules 1311 on the first substrate 110 side in the no-voltage-applied state when viewed from the top. The viewing angle control liquid crystal panel 10 of Embodiment 1 is an ECB mode liquid crystal panel containing liquid crystal molecules 131 having a positive dielectric anisotropy, and the twist angle in the no-voltage-applied state is 15° (initial twist 15°). In addition, the retardation Re of the first liquid crystal layer 130 in the voltage-applied state was 831 nm.

[0244] The color difference between the wide viewing angle mode and the narrow viewing angle mode, and the shading angle with respect to the retardation of the first liquid crystal layer 130 of the viewing angle control liquid crystal panels of Embodiments 1 to 4 and Reference Examples 1 to 7 are shown in Table 1 below, Figure 13B and Figure 14 . Figure 13B is a graph showing the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer of the viewing angle control liquid crystal panels of Embodiments 1 to 4 and Reference Examples 1 to 7. Figure 14 is a graph showing the shading angle with respect to the retardation of the first liquid crystal layer of the viewing angle control liquid crystal panels of Embodiments 1 to 4 and Reference Examples 1 to 7. The privacy performance is good when the shading angle is greater than -40°, that is, the absolute value of the shading angle is less than 40°, and the color shift is good when the color difference is 0.008 or less. Here, in the embodiments, the negative polar angle at which the transmittance becomes the lowest is set as the shading angle, and thus the shading angle being greater than -40° (the absolute value of the shading angle being less than 40°) means that the shading angle is greater than -40° and less than 0°.

[0245] [Table 1]

[0246]

[0247] As shown in Table 1 and Figure 13B and Figure 14 the liquid crystal panel 10 of Example 1 functions as a wide viewing angle mode in the no-voltage application state, and functions as a narrow viewing angle mode (negative polar angle side) that is asymmetric with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) in the voltage application state. In particular, in this narrow viewing angle mode, the retardation Re of the first liquid crystal layer 130 is 831 nm, the light blocking angle of -38° (> -40°) can be achieved, and the color shift amount (u'v' color difference) at the time of front observation at the time of switching between the wide viewing angle mode and the narrow viewing angle mode can be suppressed to 0.005123. In this way, in Example 1, the color shift at the time of switching between the wide viewing angle mode and the narrow viewing angle mode can be suppressed while maintaining a high privacy performance. It is known that if the retardation Re of the first liquid crystal layer 130 in the voltage application state is designed to be 831 nm, both the productivity and the reliability can be sufficiently ensured, the (polar) angle range that can be visually recognized can be narrowed in the narrow viewing angle mode, and the front color change can be reduced.

[0248] (Example 2)

[0249] With respect to the liquid crystal panel 10 of Example 2 having the same configuration as Example 1, the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer 130, and the light blocking angle with respect to the retardation of the first liquid crystal layer 130 were found by simulation, similarly to Example 1, except that the retardation Re of the first liquid crystal layer 130 in the voltage application state was 926 nm. The results are shown in Table 1 and Figure 13B and Figure 14 above. In addition, the liquid crystal panel 10 of Example 2 is an ECB mode liquid crystal panel containing liquid crystal molecules 131 having a positive dielectric anisotropy, and having a twist angle of 15° in the no-voltage application state (initial twist 15°).

[0250] As shown in Table 1 and Figure 13B and Figure 14As shown in Table 1 and Table 2, the liquid crystal panel 10 of Example 2 functions as a wide viewing angle mode when no voltage is applied, and functions as a narrow viewing angle mode (negative polar angle side) that is asymmetric with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) when a voltage is applied. In particular, in the narrow viewing angle mode, the retardation Re of the first liquid crystal layer 130 is 926 nm, the light blocking angle of -35° (> -40°) is achieved, and the color shift amount (u'v' color difference) at the time of front observation at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed to 0.005123. Thus, in Example 2, a lower polar angle light blocking angle than Example 1 is achieved, i.e., a higher privacy performance is achieved, and the color shift at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed. It is known that if the retardation Re of the first liquid crystal layer 130 in the voltage applied state is designed to be 926 nm, both the productivity and the reliability can be sufficiently ensured, the (polar) angular range that can be visually recognized can be narrowed in the narrow viewing angle mode, and the front color change can be reduced.

[0251] (Example 3)

[0252] With respect to the liquid crystal panel 10 of Example 3 having the same configuration as Example 1, the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer 130, and the light blocking angle with respect to the retardation of the first liquid crystal layer 130 were calculated by simulation, similarly to Example 1, except that the retardation Re of the first liquid crystal layer 130 in the voltage applied state was 1010 nm. The results are shown in Table 1 and Table 2 above. Figure 13B and Figure 14 In addition, the liquid crystal panel 10 of Example 3 is an ECB mode liquid crystal panel containing liquid crystal molecules 131 having a positive dielectric anisotropy, and having a twist angle of 15° in the no voltage applied state (initial twist 15°).

[0253] As shown in Table 1 and Table 2 above, Figure 13B and Figure 14As shown in Table 1 and Table 2, the liquid crystal panel 10 of Example 3 has a liquid crystal panel 10 of the ECB mode containing liquid crystal molecules 131 having a positive dielectric anisotropy, and a twist angle of 10° (initial twist 10°) in the state where no voltage is applied. The liquid crystal panel 10 of Example 3 functions as a wide viewing angle mode in the state where no voltage is applied, and functions as a narrow viewing angle mode (negative polar angle side) that is asymmetric with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) in the state where a voltage is applied. In particular, in the narrow viewing angle mode, the retardation Re of the first liquid crystal layer 130 is 1010 nm, the light blocking angle of -32° (> -40°) is achieved, and the color shift amount (u'v' color difference) at the time of front observation at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed to 0.005671. Thus, in Example 3, a lower polar angle of the light blocking angle than in Examples 1 and 2 is achieved, i.e., a higher privacy performance is achieved, and the color shift at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed. It is known that if the retardation Re of the first liquid crystal layer 130 in the state where a voltage is applied is designed to be 1010 nm, both the productivity and the reliability are sufficiently ensured, the range of the (polar) angle that can be visually recognized is narrowed in the narrow viewing angle mode, and the front color change is reduced.

[0254] (Example 4)

[0255] The liquid crystal panel 10 of Example 4 has the same configuration as that of Example 1, except that the azimuth angle φ2 of the director 1312A of the liquid crystal molecules 132 on the second substrate 150 side is 80° in the state where a voltage is applied, and the retardation of the first liquid crystal layer 130 is 1010 nm. As with Example 1, the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer 130, and the light blocking angle with respect to the retardation of the first liquid crystal layer 130 were obtained by simulation. The results are shown in Table 1 and Table 2 above. In addition, the liquid crystal panel 10 of Example 4 is an ECB mode liquid crystal panel containing liquid crystal molecules 131 having a positive dielectric anisotropy, and having a twist angle of 10° (initial twist 10°) in the state where no voltage is applied. Figure 13B and Figure 14

[0256] As shown in Table 1 and Table 2, the liquid crystal panel 10 of Example 3 has a liquid crystal panel 10 of the ECB mode containing liquid crystal molecules 131 having a positive dielectric anisotropy, and a twist angle of 10° (initial twist 10°) in the state where no voltage is applied. The liquid crystal panel 10 of Example 3 functions as a wide viewing angle mode in the state where no voltage is applied, and functions as a narrow viewing angle mode (negative polar angle side) that is asymmetric with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) in the state where a voltage is applied. In particular, in the narrow viewing angle mode, the retardation Re of the first liquid crystal layer 130 is 1010 nm, the light blocking angle of -32° (> -40°) is achieved, and the color shift amount (u'v' color difference) at the time of front observation at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed to 0.005671. Thus, in Example 3, a lower polar angle of the light blocking angle than in Examples 1 and 2 is achieved, i.e., a higher privacy performance is achieved, and the color shift at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed. It is known that if the retardation Re of the first liquid crystal layer 130 in the state where a voltage is applied is designed to be 1010 nm, both the productivity and the reliability are sufficiently ensured, the range of the (polar) angle that can be visually recognized is narrowed in the narrow viewing angle mode, and the front color change is reduced. Figure 13B and Figure 14 ​As shown in Table 1 and FIG. 6, the liquid crystal panel 10 for viewing angle control of Example 4 functions as a wide viewing angle mode in the state where no voltage is applied, and functions as a narrow viewing angle mode (negative polar angle side) that is asymmetric with respect to the central axis (polar angle 0°, i.e., the front direction) of the horizontal direction (azimuth angle 0°-180°) in the state where a voltage is applied. In particular, in the narrow viewing angle mode, the retardation Re of the first liquid crystal layer 130 is 1010 nm, the light blocking angle of -35° (> -40°) is achieved, and the color shift amount (u'v' color difference) at the time of front observation at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is suppressed to 0.002439. Thus, in Example 4, a light blocking angle of a lower polar angle than Example 1 and the same degree of lower polar angle as Example 2 is achieved, i.e., a higher privacy performance is achieved, and the color shift at the time of switching between the wide viewing angle mode and the narrow viewing angle mode is more suppressed. It is known that if the retardation Re of the first liquid crystal layer 130 in the state where a voltage is applied is designed to be 1010 nm, both the productivity and the reliability are sufficiently ensured, the (polar) angular range that can be visually recognized is narrowed in the narrow viewing angle mode, and the front color change is reduced.

[0257] (Reference Example 1)

[0258] The liquid crystal panel for viewing angle control of Reference Example 1 has the same configuration as Example 1 except that the retardation Re of the first liquid crystal layer in the state where a voltage is applied is 594 nm, and the azimuth angle φ1 of the director of the liquid crystal molecule on the first substrate side and the azimuth angle φ2 of the director of the liquid crystal molecule on the second substrate side are 75°. Similarly to Example 1, the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer were calculated by simulation. The results are shown in Table 1 and FIG. 6 above. Figure 13B and Figure 14 In addition, the liquid crystal panel for viewing angle control of Reference Example 1 is an ECB mode liquid crystal panel that contains the liquid crystal molecule 131 having a positive dielectric anisotropy and does not twist in the state where no voltage is applied.

[0259] The color shift amount (color difference) at the front at the time of mode switching of the liquid crystal panel for viewing angle control of Reference Example 1 is 0.009 or more, which does not satisfy the criterion (0.008 or less).

[0260] (Reference Example 2)

[0261] The reference liquid crystal panel of Example 2 having the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 653 nm, and the azimuthal angle φ1 of the director of the liquid crystal molecules on the first substrate side and the azimuthal angle φ2 of the director of the liquid crystal molecules on the second substrate side were 75° was simulated to obtain the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer, as in Example 1. The results are shown in Table 1 and Table 2 above. In addition, the reference liquid crystal panel of Example 2 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and not twisted in the voltage non-application state. The color shift amount (color difference) of the reference liquid crystal panel of Example 2 was 0.009 or more, and did not satisfy the criterion (0.008 or less). Figure 13B and Figure 14 In addition, the reference liquid crystal panel of Example 3 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and not twisted in the voltage non-application state. The color shift amount (color difference) of the reference liquid crystal panel of Example 3 was 0.009 or more, and did not satisfy the criterion (0.008 or less).

[0262] (Reference Example 3)

[0263] The reference liquid crystal panel of Example 3 having the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 713 nm, and the azimuthal angle φ1 of the director of the liquid crystal molecules on the first substrate side and the azimuthal angle φ2 of the director of the liquid crystal molecules on the second substrate side were 75° was simulated to obtain the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer, as in Example 1. The results are shown in Table 1 and Table 2 above. In addition, the reference liquid crystal panel of Example 3 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and not twisted in the voltage non-application state. The color shift amount (color difference) of the reference liquid crystal panel of Example 3 was 0.009 or more, and did not satisfy the criterion (0.008 or less). Figure 13B and Figure 14 In addition, the reference liquid crystal panel of Example 3 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and not twisted in the voltage non-application state. The color shift amount (color difference) of the reference liquid crystal panel of Example 3 was 0.009 or more, and did not satisfy the criterion (0.008 or less).

[0264] (Reference Example 4)

[0265] The reference liquid crystal panel of Example 4 having the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 760 nm, and the azimuthal angle φ1 of the director of the liquid crystal molecules on the first substrate side and the azimuthal angle φ2 of the director of the liquid crystal molecules on the second substrate side were 75° was simulated to obtain the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer, as in Example 1. The results are shown in Table 1 and Table 2 above. In addition, the reference liquid crystal panel of Example 4 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and not twisted in the voltage non-application state. The color shift amount (color difference) of the reference liquid crystal panel of Example 4 was 0.009 or more, and did not satisfy the criterion (0.008 or less). Figure 13B and Figure 14The color shift amount (color difference) of the viewing angle control liquid crystal panel of Reference Example 4 was 0.009 or more, and did not satisfy the criteria (0.008 or less).

[0266] (Reference Example 5)

[0267] The viewing angle control liquid crystal panel of Reference Example 5, which had the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 831 nm, the azimuth angle φl of the director of the liquid crystal molecules on the first substrate side, and the azimuth angle φ2 of the director of the liquid crystal molecules on the second substrate side were 75° or more, was simulated in the same manner as in Example 1 to obtain the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer. The results are shown in Table 1 and Table 2 above. Figure 13B and Figure 14 The viewing angle control liquid crystal panel of Reference Example 5 was an ECB mode liquid crystal panel containing the liquid crystal molecules 131 having a positive dielectric anisotropy, and having no twist in the no-voltage application state. The color shift amount (color difference) of the viewing angle control liquid crystal panel of Reference Example 5 was 0.009 or more, and did not satisfy the criteria (0.008 or less).

[0268] (Reference Example 6)

[0269] The viewing angle control liquid crystal panel of Reference Example 6, which had the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 926 nm, the azimuth angle φl of the director of the liquid crystal molecules on the first substrate side, and the azimuth angle φ2 of the director of the liquid crystal molecules on the second substrate side were 75° or more, was simulated in the same manner as in Example 1 to obtain the color difference between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light blocking angle with respect to the retardation of the first liquid crystal layer. The results are shown in Table 1 and Table 2 above. Figure 13B and Figure 14 The viewing angle control liquid crystal panel of Reference Example 6 was an ECB mode liquid crystal panel having no twist. The color shift amount (color difference) of the viewing angle control liquid crystal panel of Reference Example 6 was 0.009 or more, and did not satisfy the criteria (0.008 or less).

[0270] (Reference Example 7)

[0271] For the liquid crystal panel of Reference Example 7 having the same configuration as that of Example 1 except that the retardation Re of the first liquid crystal layer in the voltage application state was 1033 nm, the azimuthal angle φ1 of the director of the liquid crystal molecule on the first substrate side, and the azimuthal angle φ2 of the director of the liquid crystal molecule on the second substrate side were other than 75°, the color shift between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light shielding angle with respect to the retardation of the first liquid crystal layer were calculated by simulation in the same manner as in Example 1. The results are shown in Table 1 and FIGS. 2 and 3 above. In addition, the liquid crystal panel of Reference Example 7 was an ECB mode liquid crystal panel containing the liquid crystal molecule 131 having a positive dielectric anisotropy, and not twisted in the voltage application state. The color shift amount (color difference) of the liquid crystal panel of Reference Example 7 was 0.009 or more, and did not satisfy the criterion (0.008 or less). Figure 15 and Figure 16 In addition, the liquid crystal panel of Reference Example 8 was an ECB mode liquid crystal panel containing the liquid crystal molecule 131 having a positive dielectric anisotropy, and twisted by 30° in the voltage application state (initial twist 30°). The color shift amount (color difference) of the liquid crystal panel of Reference Example 8 was 0.009 or more, and did not satisfy the criterion (0.008 or less).

[0272] (Reference Example 8)

[0273] For the liquid crystal panel of Reference Example 8 having the same configuration as that of Example 1 except that the azimuthal angle φ1 of the director of the liquid crystal molecule on the first substrate side was 90°, and the azimuthal angle φ2 of the director of the liquid crystal molecule on the second substrate side was 60°, the color shift between the wide viewing angle mode and the narrow viewing angle mode with respect to the retardation of the first liquid crystal layer, and the light shielding angle with respect to the retardation of the first liquid crystal layer were calculated by simulation in the same manner as in Example 1. The results are shown in Table 1 and FIGS. 2 and 3 above. In addition, the liquid crystal panel of Reference Example 8 was an ECB mode liquid crystal panel containing the liquid crystal molecule 131 having a positive dielectric anisotropy, and twisted by 30° in the voltage application state (initial twist 30°). The color shift amount (color difference) of the liquid crystal panel of Reference Example 8 was 0.009 or more, and did not satisfy the criterion (0.008 or less). Figure 15 and Figure 16 In addition, the liquid crystal panel of Reference Example 8 was an ECB mode liquid crystal panel containing the liquid crystal molecule 131 having a positive dielectric anisotropy, and twisted by 30° in the voltage application state (initial twist 30°). The color shift amount (color difference) of the liquid crystal panel of Reference Example 8 was 0.009 or more, and did not satisfy the criterion (0.008 or less).

[0274] (Example 5)

[0275] Figure 17 is a cross-sectional schematic view of the display device of Example 5. Figure 17is a front surface schematic view of the display device of Example 5. The viewing angle of the display device 1 of Example 5 having the same configuration as the second embodiment was found by simulation. The simulation of the viewing angle of the display device was performed using an LCD host 2D. More specifically, in the viewing angle control liquid crystal panel, the voltage dependence of the transmittance (vertical axis) with respect to the polar angle (horizontal axis) at each azimuth (5° scale) was calculated, and the viewing angle characteristics with respect to the luminance of the viewing angle control liquid crystal panel at 0 V (wide viewing angle mode) and 5.5 V (narrow viewing angle mode) were simulated. Further, the viewing angle characteristics of the display panel were simulated in the same manner as the viewing angle control liquid crystal panel, and the viewing angle characteristics of the display device were found by cumulating the viewing angle characteristics of the viewing angle control liquid crystal panel and the display panel.

[0276] Specifically, as shown in Figure 17 and Figure 18 , the display device 1 of Example 5 has, from the back surface side toward the observation surface side, the backlight 30, the viewing angle control liquid crystal panel 10 of Example 3, and the liquid crystal display panel 20 as the display panel in this order.

[0277] In the viewing angle control liquid crystal panel 10, the azimuth angle φ1 of the director 1311A of the liquid crystal molecule 1311 on the first substrate 110 side in the no-voltage application state is 90°, and the azimuth angle φ2 of the director 1312A of the liquid crystal molecule 1312 on the second substrate 150 side is 75°. The azimuth angles of the first absorption axis 10P1A of the first polarizing plate 10P1 and the second absorption axis 10P2A of the second polarizing plate 10P2 are 90°.

[0278] In the liquid crystal display panel 20, the third polarizing plate 10P3 and the fourth polarizing plate 10P4 use linear polarizing plates of the absorption type, the azimuth angle of the third absorption axis 10P3A is 0°, and the azimuth angle of the fourth absorption axis 10P4A is 90°. In the third alignment film 220 and the fourth alignment film 240, a horizontal alignment film capable of aligning the liquid crystal molecules 231 in the horizontal direction by rubbing treatment was used. The second liquid crystal layer 230 uses positive liquid crystal molecules 231. The fourth substrate 250 has an electrode structure of the IPS type in which the third electrode 252 and the fourth electrode 254 are comb electrodes. The liquid crystal display panel 20 is an IPS mode liquid crystal panel that assumes a parallel alignment state at the time of no-voltage application. The azimuth angle of the director 231A of the liquid crystal molecules 231 included in the second liquid crystal layer 230 in the no-voltage application state is 90°.

[0279] The backlight 30 has a light guide plate with high directivity. That is, the backlight 30 is a backlight that does not switch between the public mode and the privacy mode.

[0280] Figure 19is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device 1 of Example 4. In the case where the viewing angle control liquid crystal panel 10 is in the no-voltage application state, as shown in the left side of the figure, the light (polarized light) from the backlight 30 that has passed through the viewing angle control liquid crystal panel 10 shows high transmittance in both the normal direction and the inclined direction (polar angle 45°), and is bright in both the normal direction and the inclined direction. Since the liquid crystal display panel 20 is driven in the horizontal electric field mode, the light that has passed through the viewing angle control liquid crystal panel 10 passes through the liquid crystal display panel 20 not only in the normal direction but also in the inclined direction. As a result, the light leaks out to the observation surface side with a wide polar angle, and thus the wide viewing angle mode can be realized. Figure 20

[0281] In the case where the viewing angle control liquid crystal panel 10 is in the voltage application state, as shown in the right side of the figure of Figure 18 , the light (polarized light) from the backlight 30 that has passed through the viewing angle control liquid crystal panel 10 becomes an exit light in which the transmittance is maximum at the normal direction (polar angle 0°) and the transmittance is minimum at the polar angle -30°. Since a similar angular profile is obtained also after the exit light passes through the liquid crystal display panel 20, in the narrow viewing angle mode, particularly at the left side, a small light shielding angle can be realized.

[0282] In the configuration of Example 5, since there is no viewing angle control liquid crystal panel at the most surface, there is an advantage that coexistence with the in-cell touch panel technology is possible. The display device 1 shown in Example 5 can be applied to, for example, a vehicle-mounted use, a PC use, a smart phone use, and the like.

[0283] (Example 6)

[0284] Figure 19 is a cross-sectional schematic view of the display device of Example 6. Figure 19 is a front view schematic view of the display device of Example 6. Figure 20 is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 6. As shown in Figure 20 and Figure 21 , the viewing angle of the display device 1 of Example 6 having the same configuration as the modification example 1 of the second embodiment described above is calculated by simulation similarly to Example 5. The display device 1 of Example 6 is different from Example 5 in that the viewing angle control liquid crystal panel 10 is disposed on the observation surface side of the liquid crystal display panel 20, and the axis orientation is as shown in Figure 22 ​The display device 1 shown in Fig. 6A has the same configuration as that of the display device 1 shown in Fig. 5A except for the following changes. Specifically, the azimuth angle of the first absorption axis 10P1A of the first polarizing plate 10P1 is 0°, the azimuth angle of the second absorption axis 10P2A of the second polarizing plate 10P2 is 0°, the azimuth angle of the third absorption axis 10P3A of the third polarizing plate 10P3 is 0°, and the azimuth angle of the fourth absorption axis 10P4A of the fourth polarizing plate 10P4 is 90°.

[0285] In the case where the viewing angle control liquid crystal panel 10 is in the no-voltage application state, as shown in the left side of Fig. 6B, the light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20 shows high transmittance in either of the normal direction and the inclined direction (polar angle 45°) after passing through the viewing angle control liquid crystal panel 10, and is bright in both the normal direction and the inclined direction. As a result, light leaks to the side of the viewing surface with a wide polar angle, and thus a wide viewing angle mode can be achieved. Figure 21

[0286] In the case where the viewing angle control liquid crystal panel 10 is in the voltage application state, as shown in the right side of Fig. 6B, the light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20 becomes exit light that has the maximum transmittance at the normal direction (polar angle 0°) and the minimum transmittance at the polar angle -30° after passing through the viewing angle control liquid crystal panel 10. That is, a light shielding angle of -30° can be achieved in the narrow viewing angle mode. Figure 22 By being configured as in Example 6, it is understood that the viewing angle control liquid crystal panel 10 can cut light, particularly light in the inclined direction, from the TFT diffraction of the liquid crystal display panel 20 and the scattering of the opening portion of the black matrix layer 213, and thus the light shielding force in the narrow viewing angle mode is strengthened.

[0287] Further, the display device 1 shown in Example 6 can be applied to, for example, a vehicle-mounted use, a PC use, a smartphone use, and the like.

[0288] (Example 7)

[0289]

[0290] Figure 23 is a cross-sectional schematic view of the display device of Example 7. Figure 23 is a front view of the display device of Example 7. The viewing angle of the display device 1 of Example 7 having the same configuration as that of the second modification example 2 of the second embodiment was calculated by simulation, as in Example 5.

[0291] Specifically, as shown in Figs. 6A and 6B, Figure 23 and Figure 24 ​​As shown, the display device 1 of Example 7 has, from the back surface side toward the observation surface side, the organic EL display panel 40 as the above-described display panel and the viewing angle control liquid crystal panel 10 of Example 3 in this order. A color conversion type OLED is used in the organic EL display panel 40.

[0292] In the viewing angle control liquid crystal panel 10, the azimuth angle φ1 of the director 1311A of the liquid crystal molecule 1311 on the first substrate 110 side in the no-voltage application state is 90°, and the azimuth angle φ2 of the director 1312A of the liquid crystal molecule 1312 on the second substrate 150 side is 75°. The first absorption axis 10P1A of the first polarizing plate 10P1 and the second absorption axis 10P2A of the second polarizing plate 10P2 are 90°.

[0293] The organic EL display panel 40 has, from the back surface side toward the observation surface side, a TFT substrate 410, an anode 420, a hole injection layer / hole transport layer 430, a blue light emitting layer 440, an electron injection layer / electron transport layer 450, a cathode 460, and an opposing substrate 470 in this order. The opposing substrate 470 has a black matrix layer 472 provided with a first opening portion 472X, a second opening portion 472Y, and a third opening portion 472Z on a support substrate 471, a red quantum dot sheet 473R provided in the first opening portion 472X, and a green quantum dot sheet 473G provided in the second opening portion 472Y.

[0294] Figures 25-28 is a cross-sectional schematic view illustrating the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 7. In the case where the viewing angle control liquid crystal panel 10 is in the no-voltage application state, as shown in the left side of the figure of Figure 25 As shown in the left side of the figure of

[0295] In the case where the viewing angle control liquid crystal panel 10 is in the voltage application state, as shown in the right side of the figure of Figure 26 As shown in the right side of the figure of

[0296] In the configuration of Embodiment 7, the organic EL display panel 40 is used as the above-described display panel, and thus, compared with the case where the liquid crystal display panel 20 is used, it is possible to realize a thinner and lighter display device, and it is suitable for mobile use. The display device 1 of Embodiment 7 is suitable for, for example, in-vehicle use, PC use, smart phone use, and the like.

[0297] (Embodiments 8-1 to 8-4)

[0298] Figure 26 are cross-sectional schematic views that explain the viewing angle in the narrow viewing angle mode of the display devices of Embodiments 8-1 to 8-4. Figure 27 are views that respectively represent the pattern of the first electrode possessed by the display devices of Embodiments 8-1 to 8-4. In Figure 28 and Figure 28 , for example, the width W between characters can be made 0.25 mm, and the width S of the character line can be made 0.5 mm. Figure 29 The trademark of Figure 29 and Figures 25-28 , for example, the width W between characters can be made 0.35 mm, and the width S of the character line can be made 0.5 mm. Figure 24 The trademark of Figures 25-28 , for example, can be inclined by 30°. Figures 25-28 is a view that represents one example of the appearance of a sample in the narrow viewing angle mode and the wide viewing angle mode of the display devices of Embodiments 8-1 to 8-4.

[0299] As shown in Figure 29 , the viewing angle of the display devices of Embodiments 8-1 to 8-4, which have the same configuration as Embodiment 6 except that the trademark of the first electrode 112 is patterned and the retardation Re of the first liquid crystal layer 130 in the voltage application state is 800 nm, was also obtained by simulation in the same manner as Embodiment 5. Here, as a result of the research by the present inventors, it was found that in the case where the retardation Re of the first liquid crystal layer in the voltage application state is 600 nm, the front surface transmittance differs between the wide viewing angle mode and the narrow viewing angle mode (a difference of about 13% is generated), and thus, the trademark is visible from the front surface. Therefore, in the display devices of Embodiments 8-1 to 8-4, since the difference in the front surface transmittance between the wide viewing angle mode and the narrow viewing angle mode is suppressed (approximately 0%), the trademark is visually recognized only when the display device is observed obliquely, and the trademark character is not visually recognized when the display device is observed from the front surface, and thus, the retardation Re of the first liquid crystal layer 130 in the voltage application state is set to 800 nm.

[0300] As shown in Figure 24As shown, the first electrode 112 of the viewing angle control liquid crystal panel 10 of the display device 1 of Embodiments 8-1 to 8-4 is patterned in accordance with the character of the SHARP trademark as shown. That is, in the first electrode 112, the opening portion 112X of the ITO electrode is provided in correspondence with the portion of the SHARP trademark. Figure 29

[0301] As shown, the display device 1 of Embodiments 8-1 to 8-4 is provided with the viewing angle control liquid crystal panel 10 having the first electrode 112 from which the trademark of the ITO electrode is removed; and the liquid crystal display panel 20. Figure 28

[0302] In the case where the viewing angle control liquid crystal panel 10 is in the no-voltage application state, the light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20, after passing through the viewing angle control liquid crystal panel 10 (the liquid crystal panel of the ECB mode having the asymmetric viewing angle with the trademark), shows high transmittance in either of the normal direction and the inclined direction (polar angle -30°), and is bright in both the normal direction and the inclined direction. As a result, as shown, the light leaks out to the side of the viewing surface with a wide polar angle, and thus a wide viewing angle mode can be realized. Figure 30

[0303] In the case where the viewing angle control liquid crystal panel 10 is in the voltage application state, as shown in Figure 31 and Figure 30 the light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20, after passing through the viewing angle control liquid crystal panel 10, becomes the emergent light that has the maximum transmittance at the normal direction (polar angle 0°) and the minimum transmittance at the polar angle -30°. That is, in the narrow viewing angle mode, the light blocking angle -30° can be realized. At this time, the portion of the SHARP trademark transmits light, and is displayed as a character, and thus it is difficult to see the content written in "Email account" of the liquid crystal display panel 20 disposed more on the back surface side than the viewing angle control liquid crystal panel 10, compared to the case where there is no SHARP trademark, and the privacy performance can be further improved. Further, as shown in Embodiment 8-4, if the trademark is slightly increased in size and the density is reduced, the privacy performance at the polar angle -30° can be further improved. Figure 31

[0304] Further, the display device 1 shown in Embodiments 8-1 to 8-4 can be applied to, for example, a vehicle-mounted use, a PC use, a smart phone use, and the like.

[0305] (Embodiment 9)

[0306] Figure 31 is a cross-sectional schematic view of the display device of Embodiment 9. ​ ​​​​is a cross-sectional schematic view for explaining the viewing angle in the narrow viewing angle mode and the wide viewing angle mode of the display device of Example 9. The viewing angle of the display device 1 of Example 9 shown in FIG. 9 was obtained by simulation similarly to Example 5. ​ The display device 1 of Example 9 shown in FIG. 9 has the same configuration as that of Example 5 except for the configuration of the backlight 30. The backlight 30 of Example 9 has, from the back surface side toward the observation surface side, an ESR (Enhanced Specular Reflector) 31 manufactured by 3M Company, a privacy light guide plate 32 having an LED 32L at the end portion, a louver film 33 that cuts light in the left-right direction, and a public light guide plate 34 having an LED 34L at the end portion. The ESR 31 is an optical film formed of a polyester-based resin (multilayer film configuration) having a reflectance of 98% or more. The public light guide plate 34 has a function of diffusing light from the LED 34L by using a structure body engraved on the public light guide plate 34, thereby causing the diffused light to exit toward the viewing angle control liquid crystal panel 10. The privacy light guide plate 32 has a function of causing light having directivity to exit toward the viewing angle control liquid crystal panel 10 by passing light from the LED 32L through the louver film 33.

[0307] In a case where the viewing angle control liquid crystal panel 10 is in the no-voltage application state, the LED 32L disposed at the end portion of the privacy light guide plate 32 is in the off state, and the LED 34L disposed at the end portion of the public light guide plate 34 is in the on state, as shown in the left side of FIG. 8, light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20, after passing through the viewing angle control liquid crystal panel 10, shows high transmittance in either of the front direction and the inclined direction (polar angle 45°), and is bright in both the front direction and the inclined direction. As a result, light leaks out toward the observation surface side with a wide polar angle, and thus the wide viewing angle mode can be achieved. ​ In a case where the viewing angle control liquid crystal panel 10 is in the voltage application state, the LED 32L disposed at the end portion of the privacy light guide plate 32 is in the on state, and the LED 34L disposed at the end portion of the public light guide plate 34 is in the off state, as shown in the right side of FIG. 8, light (polarized light) from the backlight 30 that has passed through the liquid crystal display panel 20, after passing through the viewing angle control liquid crystal panel 10, becomes exit light in which the transmittance is maximum at the front direction (polar angle 0°) and the transmittance is minimum at the polar angle -30°. That is, the light shielding angle -30° can be achieved in the narrow viewing angle mode.

[0308] ​

[0309] ​​By using the double light guide plate of the privacy light guide plate 32 and the public light guide plate 34, it is possible to increase the brightness modulation width in the tilt direction (one-side tilt polar angle) in the wide viewing angle mode and the narrow viewing angle mode (i.e., it is possible to obtain a wide brightness control range). Thereby, it is possible to make the mode switching more moderate, it is possible to more strongly shield light in the narrow viewing angle mode, and it is possible to further improve the brightness in the wide viewing angle mode.

[0310] REFERENCE NUMERALS

[0311] 1: Display device

[0312] 10: Viewing angle control liquid crystal panel

[0313] 10P1: First polarizing plate

[0314] 10P1A: First absorption axis

[0315] 10P1B: First transmission axis

[0316] 10P2: Second polarizing plate

[0317] 10P2A: Second absorption axis

[0318] 10P2B: Second transmission axis

[0319] 10P3: Third polarizing plate

[0320] 10P3A: Third absorption axis

[0321] 10P4: Fourth polarizing plate

[0322] 10P4A: Fourth absorption axis

[0323] 11P, 21P: Pixel

[0324] 20: Liquid crystal display panel

[0325] 30, 30N: Backlight

[0326] 31: ESR

[0327] 32: Privacy light guide plate

[0328] 32L, 34L, 36L, 39L: LED

[0329] 33, 38, 381: Louver film

[0330] 34, 39: Public light guide plate

[0331] 35: Reflective plate

[0332] 36: Conventional light guide plate

[0333] 37: Prism sheet

[0334] 40: Organic EL display panel

[0335] 50: Screen

[0336] 110: First substrate

[0337] 111: First support substrate

[0338] 112: First electrode

[0339] 112X: Opening

[0340] 120: First alignment film

[0341] 130: Liquid crystal layer (first liquid crystal layer)

[0342] 131, 1311, 1312, 231: Liquid crystal molecule

[0343] 131A, 1311A, 1312A, 231A: Director

[0344] 140: Second alignment film

[0345] 150: Second substrate

[0346] 151: Second support substrate

[0347] 152: Second electrode

[0348] 153, 256: Gate line

[0349] 154, 257: Source line

[0350] 155: TFT (Thin Film Transistor)

[0351] 160: Negative C-plate

[0352] 210: Third substrate

[0353] 211: Third support substrate

[0354] 212: Color filter layer

[0355] 212C, 212CB, 212CG, 212CR: Color filter

[0356] 213: Black matrix layer

[0357] 213S: Opening

[0358] 220: Third alignment film

[0359] 230: Second liquid crystal layer

[0360] 240: fourth alignment film

[0361] 250: fourth substrate

[0362] 250P: pixel electrode

[0363] 250PS: slit

[0364] 251: fourth support substrate

[0365] 252: third electrode

[0366] 253: insulating layer

[0367] 254: fourth electrode

[0368] 254a: linear electrode portion

[0369] 254b: opening

[0370] 410: TFT substrate

[0371] 420: anode

[0372] 430: hole injection layer / hole transport layer

[0373] 440: blue light-emitting layer

[0374] 450: electron injection layer / electron transport layer

[0375] 460: cathode

[0376] 470: counter substrate

[0377] 471: support substrate

[0378] 472: black matrix layer

[0379] 472X: first opening portion

[0380] 472Y: second opening portion

[0381] 472Y: third opening portion

[0382] 473G: green quantum dot sheet

[0383] 473R: red quantum dot sheet

[0384] S, W: width

Claims

1. A liquid crystal panel, characterized by comprising: the liquid crystal panel comprises, in order: a first polarizing plate having a first absorption axis, a first substrate having a first electrode, a liquid crystal layer containing liquid crystal molecules, and a second substrate having a second electrode, when an azimuth angle of a director of the liquid crystal molecules on the first substrate side in a no-voltage application state is set as φ1, an azimuth angle of a director of the liquid crystal molecules on the second substrate side is set as φ2, and an azimuth angle of the first absorption axis of the first polarizing plate is set as φP1, (Formula 1) is satisfied, and (Formula 2-1) or (Formula 2-2) is satisfied, 5°≤|φ1-φ2|≤20° …… (Formula 1); 5°≤|φP1-φ2|≤20° …… (Formula 2-1); 65°≤|φP1-φ2|≤80° …… (Formula 2-2).

2. The liquid crystal panel according to claim 1, characterized by, the second substrate further comprises a second polarizing plate on a side opposite to the liquid crystal layer, the second polarizing plate having a second absorption axis parallel to the first absorption axis.

3. The liquid crystal panel according to claim 1, characterized in that: the first electrode and the second electrode are whole-surface electrodes, a retardation Re of the liquid crystal layer in a no-voltage application state is 700 nm or more and 1200 nm or less.

4. The liquid crystal panel according to claim 1, wherein the liquid crystal molecules have a positive dielectric anisotropy.

5. The liquid crystal panel according to claim 1, wherein a negative C-plate having a retardation Rth of 500 nm or more in a thickness direction is further included, the negative C-plate being disposed between the first polarizing plate and the first substrate.

6. A display device, characterized by comprising: it includes: the liquid crystal panel according to any one of claims 1 to 5; and a display panel.

7. The display device according to claim 6, characterized in that: the liquid crystal layer is a first liquid crystal layer, the display panel comprises, in order: a third polarizing plate having a third absorption axis, a second liquid crystal layer, and a fourth polarizing plate having a fourth absorption axis orthogonal to the third absorption axis, of the third polarizing plate and the fourth polarizing plate, the absorption axis of the polarizing plate on the side closer to the liquid crystal panel is parallel to the first absorption axis.

8. The display device according to claim 6, wherein the display panel is a liquid crystal display panel of an IPS mode or an FFS mode.

9. The display device according to claim 6, characterized in that: the display device further comprises a backlight, the backlight has two light guide plates, one of the two light guide plates functions as a wide viewing angle mode, and the other functions as a narrow viewing angle mode.

10. The display device according to claim 6, wherein the display panel is an organic EL display panel, an inorganic EL display panel, a micro LED display panel, or a QLED display panel.

11. The display device according to claim 6, characterized in that: the display panel has a third substrate, a second liquid crystal layer, and a fourth substrate, the third substrate comprises color filters of a plurality of colors, the fourth substrate comprises pixel electrodes, the color filters of the plurality of colors and the pixel electrodes are each in a long strip shape, the long side direction of the color filters of the plurality of colors and the pixel electrodes is respectively arranged in a vertical direction of the display panel.

12. The display device according to claim 6, characterized in that: the display panel has a third substrate, a second liquid crystal layer, and a fourth substrate, The third substrate includes color filters of a plurality of colors, The fourth substrate includes pixel electrodes, The color filters of the plurality of colors and the pixel electrodes are each in a long strip shape, Long side directions of the color filters of the plurality of colors and the pixel electrodes are each arranged in a left-right direction of the display panel.

13. The display device according to claim 12, wherein The third substrate includes a black matrix layer provided with a plurality of opening portions each corresponding to the color filters of the plurality of colors, The plurality of opening portions each have a width WB in a left-right direction of the display panel of 80 µm or more and 140 µm or less, The plurality of opening portions each have a width LB in an up-down direction of the display panel of 80 µm or less.

Images