Liquid crystal panel and graphic display device

Abstract

To provide a liquid crystal panel that can control a viewing angle while reducing its thickness, and a graphic display device including the liquid crystal panel.SOLUTION: A liquid crystal panel includes a first transparent substrate, a first electrode, a liquid crystal layer, a second electrode, and a second transparent substrate in this order. The liquid crystal layer contains polymer dispersion type liquid crystal and / or a guest-host type liquid crystal including dichroic dye, and includes a superimposed area superimposed on the second electrode and a non-superimposed area not superimposed on the second electrode, and thereby the liquid crystal layer has a transparent area, and a switching area switching between a transmission state and a scattered or absorption state.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The following disclosure relates to a liquid crystal panel and an image display device. [Background technology]

[0002] A liquid crystal panel is an optical element that controls the amount of light transmission by applying a voltage to a liquid crystal composition sealed between a pair of substrates and changing the alignment state of the liquid crystal molecules in the liquid crystal composition in response to the applied voltage. Taking advantage of their features such as thinness, light weight, and low power consumption, such liquid crystal panels are used in a wide range of fields, such as image display devices.

[0003] In recent years, in the field of video display devices, improvements in viewing angle characteristics have been studied so that the same image can be observed whether the image is observed from a narrow viewing angle range or a wide viewing angle range. On the other hand, from the viewpoint of maintaining privacy, a display method has been studied in which an image can be observed from a narrow viewing angle range but is difficult to observe from a wide viewing angle range. Thus, there is a demand for a display device that can be switched between a public mode (also called a wide viewing angle mode) in which the same image can be observed from a narrow viewing angle range and a wide viewing angle range, and a privacy mode (also called a narrow viewing angle mode) in which the image can be observed from a narrow viewing angle range but is difficult to observe from a wide viewing angle range.

[0004] Regarding a technology for switching viewing angle modes, for example, Patent Document 1 discloses an optical element having a first region made of a light-transmitting material between a pair of transparent substrates, and a second region disposed between the first region and containing a liquid crystal material that can be selectively switched between a light-transmitting state and a scattering or absorbing state. Patent Document 2 discloses a viewing angle control element that faces one pixel and includes a first region having a certain transmittance, and a second region that can be switched between a certain transmittance and a certain transmittance smaller than the first transmittance. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-206373 A [Patent Document 2] JP 2005-221756 A Summary of the Invention [Problem to be solved by the invention]

[0006] Fig. 20A is a schematic cross-sectional view illustrating a wide viewing angle mode of an image display device 1R of a comparative embodiment. Fig. 20B is a schematic cross-sectional view illustrating a narrow viewing angle mode of an image display device 1R of a comparative embodiment. The image display device 1R shown in Figs. 20A and 20B includes, in order from the observation surface side to the rear surface side, a display panel 10, a liquid crystal panel 20R including polymer dispersed liquid crystal (PDLC), a louver layer 30R, and a backlight 40.

[0007] The display panel 10 includes, from the observation surface side to the rear surface side, a color filter (CF) substrate 110 including a CF layer, and a TFT substrate 120 including thin film transistors (TFTs).

[0008] The liquid crystal panel 20R includes a pair of electrodes 230 between a pair of transparent substrates 210 and 220, and a liquid crystal layer 240R made of PDLC sandwiched between the electrodes. PDLC has a structure in which liquid crystal components are dispersed in a polymer network. As shown in FIG. 20A and FIG. 20B, the liquid crystal panel 20R can switch between a transmissive state and a scattering state by utilizing the refractive index difference between the liquid crystal component and the polymer network, which is caused by changing the orientation state of the liquid crystal component by applying a voltage to the liquid crystal layer 240R. When a PDLC type that scatters when no voltage is applied is used, the liquid crystal panel 20R is in a scattering state when no voltage is applied, and in a transmissive state when a voltage is applied.

[0009] The louver layer 30R has a configuration in which light-shielding portions 31 made mainly of a light absorbing material and transparent portions 32 made mainly of a transparent resin are alternately arranged in parallel. The louver layer 30R has a function of transmitting light 1LA coming from the front direction and blocking light 1LB coming from an oblique direction out of the light coming from the backlight 40. In other words, the louver layer 30R has a function of transmitting light at a low polar angle and blocking light at a high polar angle.

[0010] In the image display device 1R, in both the wide viewing angle mode and the narrow viewing angle mode, the oblique light 1LB from the backlight 40 is blocked (cut) by the louver layer 30R, and only the light 1LA in the front direction is transmitted through the louver layer 30R (see Figs. 20A and 20B). When no voltage is applied, the light 1LA in the front direction that has transmitted through the louver layer 30R is scattered (attenuated) in the liquid crystal panel 20R, causing the light to spread, and enters the display panel 10 (see Fig. 20A). On the other hand, when a voltage is applied, the light 1LA in the front direction that has transmitted through the louver layer 30R is not scattered, transmits through the liquid crystal panel 20R, and enters the display panel 10 (see Fig. 20B).

[0011] In this way, when no voltage is applied, the image display device 1R can transmit backlight from the low polar angle side to the high polar angle side, realizing a wide viewing angle mode, while when a voltage is applied, the backlight is not transmitted on the high polar angle side and can transmit backlight only on the low polar angle side, realizing a narrow viewing angle mode. However, in order to switch between the wide viewing angle mode and the narrow viewing angle mode, the liquid crystal panel 20R and the louver layer 30R are separately added as components to the display panel 10, which creates a problem of increased thickness.

[0012] In the optical element described in Patent Document 1, a first region in a light-transmitting state and a second region in which the light-transmitting state and a scattering or absorbing state can be selectively switched are physically distinguished by using different materials for these regions. Such optical elements have had various problems in practical use, such as the difficulty of narrowing the viewing angle using normal liquid crystal processes and the complexity of the manufacturing process.

[0013] For example, Patent Document 1 states that UV photosensitive resin is preferable as the light-transmitting material forming the first region. When UV photosensitive resin is used, the thickness of the resin layer becomes thick. In this regard, Patent Document 1 describes an example of a pattern of a composite material forming the second region to obtain a narrow viewing angle (60°), in which the width is 10 to 30 μm, the pitch is 200 μm, and the height is 300 μm. The thickness of the light-transmitting material forming the first region corresponds to the height of this pattern example, but it is difficult to achieve the height of 300 μm with a normal liquid crystal process (generally within 10 μm). Therefore, when UV photosensitive resin is used as the light-transmitting material, it is difficult to narrow the viewing angle. As the light-transmitting material, a polymer material containing liquid crystal molecules, more specifically, a UV-curable composite material in which liquid crystal molecules are dispersed in a UV-curable polymer, is also exemplified. In this case, in order to make the first region light-transmitting, a process of applying a voltage and UV curing is required, as shown in FIG. 11 of Patent Document 1. This complicates the manufacturing process of the optical element.

[0014] For example, the viewing angle control element described in Patent Document 2 has a first region composed of a columnar translucent resin layer and a second region composed of a liquid crystal layer. In this case, since a fine pattern of the columnar translucent resin layer can be formed with good dimensional accuracy using general photolithography, the viewing angle control element can be manufactured without changing the existing liquid crystal manufacturing process. Therefore, the viewing angle control element can prevent deterioration of image quality due to a decrease in luminance of the image display element at a wide viewing angle while realizing both a wide viewing angle and a narrow viewing angle, and is extremely useful in the field of display devices. However, there is room for further devising to simplify the manufacturing process and make viewing angle control even easier.

[0015] The present invention has been made in consideration of the above-mentioned current situation, and has an object to provide a liquid crystal panel that can control the viewing angle while reducing the thickness, and an image display device including such a liquid crystal panel. [Means for solving the problem]

[0016] (1) One embodiment of the present invention is a liquid crystal panel comprising, in this order, a first transparent substrate, a first electrode, a liquid crystal layer, a second electrode, and a second transparent substrate, wherein the liquid crystal layer contains a polymer dispersed liquid crystal and / or a guest-host type liquid crystal containing a dichroic dye, and comprises an overlapping region overlapping the second electrode and a non-overlapping region not overlapping the second electrode, such that the liquid crystal layer has a transparent region and a switching region where the liquid crystal layer switches between a transmissive state and a scattering or absorbing state.

[0017] (2) Moreover, in addition to the configuration of (1) above, another embodiment of the present invention is a liquid crystal panel, wherein the second electrodes are arranged in a stripe pattern or a grid pattern in a plan view.

[0018] (3) Furthermore, in one embodiment of the present invention, in addition to the configuration of (1) or (2) above, a liquid crystal panel further includes an interlayer insulating film and a third electrode, in this order from the second electrode side, between the second electrode and the second transparent substrate.

[0019] (4) Moreover, in addition to the configuration of (3), an embodiment of the present invention is a liquid crystal panel, in which different voltages can be applied to the transparent region and the switching region, respectively.

[0020] (5) Moreover, in one embodiment of the present invention, in addition to the configuration of (1), (2), (3), or (4), the non-overlapping region has a thickness of 30 μm or less.

[0021] (6) Furthermore, in one embodiment of the present invention, in addition to the configuration of (1), (2), (3), (4) or (5), the second electrode is a transparent electrode or an electrode containing a light absorbing material.

[0022] (7) Also, one embodiment of the present invention is an image display device comprising a liquid crystal panel according to (1), (2), (3), (4), (5) or (6) above, and a display panel that displays an image.

[0023] (8) Moreover, an embodiment of the present invention is an image display device further comprising a backlight in addition to the configuration of (7) above.

[0024] (9) Moreover, in one embodiment of the present invention, in addition to the configuration of (8) above, the backlight has a local dimming function.

[0025] (10) Moreover, in an embodiment of the present invention, in addition to the configuration of (7), (8), or (9), the display panel is a liquid crystal display panel or a self-luminous display panel. Effect of the Invention

[0026] According to the present invention, it is possible to provide a liquid crystal panel capable of controlling the viewing angle while suppressing the thickness, and an image display device including the liquid crystal panel. [Brief description of the drawings]

[0027] [Figure 1] 1 is a schematic cross-sectional view of a liquid crystal panel according to embodiment 1 (example 1). [Figure 2A] FIG. 2 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of the first embodiment. [Figure 2B] FIG. 2 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel of the first embodiment. [Diagram 3] 1 is a conceptual diagram for explaining a thickness D of a non-overlapping region, a width W1 of a non-overlapping region, a width W2 of an overlapping region, and a viewing angle θ. [Figure 4] 1 is a cross-sectional view illustrating an image display device according to a first embodiment of the present invention. [Figure 5A] FIG. 2 is a cross-sectional view illustrating a wide viewing angle mode of the image display device according to the first embodiment. [Figure 5B] FIG. 2 is a cross-sectional view illustrating a narrow viewing angle mode of the image display device according to the first embodiment. [Figure 6] 10 is a cross-sectional view illustrating a modification of the image display device according to the first embodiment. FIG. [Figure 7]4 is a plan view illustrating an arrangement of second electrodes in the liquid crystal panel of Embodiment 1. FIG. [Figure 8] 11 is a plan view showing an arrangement of second electrodes in a liquid crystal panel according to Embodiment 2 (Example 2). FIG. [Figure 9] 11 is a cross-sectional view illustrating a liquid crystal panel according to the third embodiment (Example 3). FIG. [Figure 10A] 4 is a cross-sectional view illustrating a liquid crystal panel according to embodiment 4 (example 4-1). FIG. [Figure 10B] 13 is a cross-sectional view illustrating a liquid crystal panel according to a modified example (Example 4-2) of Embodiment 4. FIG. [Figure 11A] FIG. 13 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of embodiment 5 (example 5). [Figure 11B] FIG. 13 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel according to the fifth embodiment. [Figure 12A] FIG. 13 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of embodiment 6 (example 6). [Figure 12B] FIG. 13 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel of embodiment 6. [Figure 13A] FIG. 13 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of embodiment 7 (example 7). [Figure 13B] FIG. 13 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel of embodiment 7. [Figure 14A] FIG. 13 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of embodiment 8 (example 8). [Figure 14B] FIG. 13 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel of embodiment 8. [Figure 15A] FIG. 13 is a cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel of Embodiment 9 (Example 9). [Figure 15B] FIG. 13 is a cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel of Embodiment 9. [Figure 16] 13 is a cross-sectional view of an image display device according to a tenth embodiment (example 10). FIG. [Figure 17A]4 is a waveform diagram of voltages of the electrodes in the image display device of Example 1 in a wide viewing angle mode. FIG. [Figure 17B] 4 is a waveform diagram of voltages of the electrodes in the narrow viewing angle mode in the image display device of Example 1. FIG. [Figure 18A] FIG. 13 is a waveform diagram of voltages of the electrodes in the image display device of Example 7 in a wide viewing angle mode. [Figure 18B] FIG. 13 is a waveform diagram of voltages of the electrodes in a narrow viewing angle mode in the image display device of Example 7. [Figure 19A] FIG. 23 is a waveform diagram of voltages of the electrodes in the image display device of Example 8 in a wide viewing angle mode. [Figure 19B] FIG. 23 is a waveform diagram of voltages of the electrodes in the narrow viewing angle mode in the image display device of Example 8. [Figure 20A] FIG. 13 is a schematic cross-sectional view illustrating a wide viewing angle mode of an image display device of a comparative example. [Figure 20B] FIG. 13 is a schematic cross-sectional view illustrating a narrow viewing angle mode of an image display device of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] (Definition of terms) In this specification, the observation side means the side closer to the screen (display surface) of the image display device, and the rear side means the side farther from the screen (display surface) of the image display device.

[0029] The polar angle means the angle between the direction of interest (eg, the measurement direction) and the normal direction to the panel surface of the liquid crystal panel. Azimuth (φ) refers to the direction of the target direction when it is projected onto the screen of an LCD panel, and is expressed as the angle (azimuth angle) between the target direction and a reference direction. Here, the reference orientation (φ=0°) is set to the horizontal right direction of the LCD panel screen. For angles and azimuth angles, a counterclockwise angle from the reference orientation is a positive angle, and a clockwise angle from the reference orientation is a negative angle. Both counterclockwise and clockwise refer to the rotation direction when the LCD panel screen is viewed from the observation surface side (front). Additionally, the angle refers to a value measured when the LCD panel screen is viewed in a flat view.

[0030] In this specification, being parallel to each other means that the angle (absolute value) between the two is within the range of 0±3°, preferably within the range of 0±1°, more preferably within the range of 0±0.5°, and particularly preferably 0° (completely parallel).

[0031] The no-voltage-applied state refers to a state in which the voltage applied to the liquid crystal layer is less than the threshold voltage (including no voltage application). The voltage-applied state refers to a state in which the voltage applied to the liquid crystal layer is equal to or greater than the threshold voltage. In this specification, the no-voltage-applied state is also referred to as when no voltage is applied, and the voltage-applied state is also referred to as when a voltage is applied.

[0032] For light transmittance, the luminance of the LED backlight and the luminance of the sample placed on the LED backlight were measured, and the light transmittance of the sample was calculated by normalizing it with the luminance of the LED backlight. For the measurement, a spectroradiometer SR-UL1 manufactured by Topcon was used. The light reflectance was measured using a spectrophotometer CM-2600d manufactured by Konica Minolta (measurement wavelength range: 360nm to 740nm, integrating sphere method).

[0033] Hereinafter, an embodiment of the present invention will be described. The present invention is not limited to the contents described in the following embodiment, and appropriate design changes can be made within the scope of the configuration of the present invention.

[0034] (Embodiment 1) FIG. 1 is a schematic cross-sectional view of a liquid crystal panel according to this embodiment. FIG. 2A is a schematic cross-sectional view illustrating a wide viewing angle mode of the liquid crystal panel according to this embodiment. FIG. 2B is a schematic cross-sectional view illustrating a narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in FIG. 1, FIG. 2A, and FIG. 2B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order. Between the second electrode 232 and the second transparent substrate 220, an interlayer insulating film 250 and a third electrode 233 are further included in this order from the second electrode 232 side. The liquid crystal panel 20 has a function of controlling the viewing angle, and therefore can be called a "viewing angle control cell".

[0035] The liquid crystal layer 240 includes a polymer dispersed liquid crystal (hereinafter, also referred to as "PDLC") In this embodiment, a type of PDLC that scatters when no voltage is applied is used.

[0036] The liquid crystal layer 240 also has an overlapping region 241 that overlaps the second electrode 232 and a non-overlapping region 242 that does not overlap the second electrode 232. By including PDLC and having the overlapping region 241 and the non-overlapping region 242, the liquid crystal layer 240 has a transparent region 244 and a switching region 243 that switches between a transmissive state and a scattering state. Depending on the design of the power supply, the overlapping region 241 can be the switching region 243 and the non-overlapping region 242 can be the transparent region 244, or the overlapping region 241 can be the transparent region 244 and the non-overlapping region 242 can be the switching region 243. In this embodiment, the switching region 243 is designed to be switched between a transparent state and a scattering state by application or non-application of a voltage (262) between the first electrode 231 and the second electrode 232, so that the overlapping region 241 becomes the switching region 243 and the non-overlapping region 242 becomes the transparent region 244 (see Figs. 1, 2A and 2B). However, in reality, it is not only the overlapping region 241 that becomes the switching region 243, but depending on the state of the electric field between the electrodes, the boundary portion between the overlapping region 241 and the non-overlapping region 242 may also become the switching region 243, or other portions may also become the switching region 243.

[0037] The important point of the present invention is that the liquid crystal layer 240 contains a predetermined liquid crystal and has an overlapping region 241 overlapping the second electrode 232 and a non-overlapping region 242 not overlapping the second electrode 232, so that the liquid crystal layer 240 has a transparent region 244 and a switching region 243 that switches between a transmission state and a scattering (or absorbing) state. That is, the important feature of the present invention is that by applying a voltage to each electrode, the transparent region 244 with high transmittance and the scattering region (or absorbing region) with low transmittance are formed in the liquid crystal layer 240, so that the liquid crystal layer 240 itself can act as a louver that can be switched on and off. Therefore, there is no particular limitation on the positions of the transparent region 244 and the switching region 243, and which regions correspond to the transparent region 244 and the switching region 243. In other words, the transparent region 244 and the switching region 243 are not limited to the forms shown in Figures 1, 2A, and 2B, and can be appropriately controlled, for example, by the width and pitch of the second electrode 232, the cell thickness (i.e., the thickness D of the non-overlapping region 242), the voltage applied to each electrode, etc.

[0038] In this embodiment, the second electrode 232 and the third electrode 233 are disposed with the interlayer insulating film 250 sandwiched therebetween. In this case, the first electrode 231 functions as a common electrode, and the first electrode 231 and the third electrode 233 control whether or not a voltage is applied to the non-overlapping region 242 (transparent region 244), and the first electrode 231 and the second electrode 232 control whether or not a voltage is applied to the overlapping region 241 (switching region 243). Therefore, in this embodiment, different voltages can be applied to the transparent region 244 and the switching region 243, respectively. Such an electrode structure is very useful because it can accommodate various driving methods in the field of image display devices.

[0039] The transparent region 244 is a region that exhibits a transmissive state by application of a voltage between the first electrode 231 and the third electrode 233 (261). The transmissive state is a state that is transparent to light. On the other hand, the switching region 243 is a region that switches between a transmissive state and a scattering or absorbing state. In this embodiment using PDLC, the switching region 243 is a region that switches between a transmissive state and a scattering state. The scattering state is a state in which light is scattered, and has a lower transmittance than the transmissive state. In this embodiment, the liquid crystal layer 240 in the scattering state is in a state similar to that of frosted glass.

[0040] In this embodiment, as described below, in the wide viewing angle mode (see FIG. 2A), the transparent region 244 and the switching region 243 have a certain transmittance (also referred to as visible light transmittance or light transmittance) T1. On the other hand, in the narrow viewing angle mode (see FIG. 2B), the transparent region 244 has a transmittance T2, and the switching region 243 has a transmittance T3 due to scattering (where T1, T2, and T3 satisfy the relationship "T1≧T2>T3"). The transmittance T1 may be 100%. T3 may be 0%.

[0041] As shown in FIG. 2A and FIG. 2B, light is incident on the liquid crystal panel 20 from the rear side (specifically, the backlight 40). When the liquid crystal layer 240 includes PDLC having a scattering property when no voltage is applied, in a state where a voltage is applied between the first electrode 231 and the second electrode 232 (262) and a voltage is applied between the first electrode 231 and the third electrode 233 (261) (voltage applied state), the overlapping area 241 and the non-overlapping area 242 are not distinguished and are integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent area) (see FIG. 2A). That is, the transparent area 244 and the switching area 243 are in a state having a transmittance T1. In this case, the light incident on the liquid crystal panel 20 from the backlight 40 passes through the liquid crystal panel 20 as it is, both in the front direction and in the oblique direction (see FIG. 2A). As a result, light from the rear side (specifically, the backlight 40) can be transmitted without loss from the low polar angle side to the high polar angle side, making it possible to realize a wide viewing angle mode with high brightness.

[0042] Here, in the image display device 1R of the comparative embodiment, in the wide viewing angle mode, the louver layer 30R cuts the oblique light 1LB even though it is not necessary to cut it (see part (z) in FIG. 20A). Furthermore, in order to widen the light narrowed by the louver layer 30R, the PDLC layer 240R scatters (attenuates) the light (see part (y) in FIG. 20A). Therefore, transmission loss occurs in both the louver layer 30R and the PDLC layer 240R, and therefore the brightness in the wide viewing angle mode is insufficient. In contrast, the liquid crystal panel 20 of the present embodiment can transmit the light from the backlight 40 without loss as described above, and can therefore achieve high brightness in the wide viewing angle mode.

[0043] In this embodiment, in a state where no voltage is applied between the first electrode 231 and the second electrode 232 (262) and a voltage is applied between the first electrode 231 and the third electrode 233 (261) (voltage non-application state), the liquid crystal layer 240 itself acts as a louver. That is, among the light incident on the liquid crystal layer 240 from the backlight 40, the oblique light 1LB is scattered (attenuated) in the overlapping region 241 (switching region 243) and passes through the liquid crystal panel 20 as attenuated light (see (a) of FIG. 2B). Here, the overlapping region 241 (switching region 243) is in a scattering state, whereas the non-overlapping region 242 (transparent region 244) remains in a transmitting state. That is, the transparent region 244 has a transmittance T2, and the switching region 243 has a transmittance T3 due to scattering (where T1≧T2>T3). Of the light incident on the liquid crystal layer 240 from the backlight 40, the light 1LA in the front direction is transmitted through the liquid crystal panel 20 without being attenuated (see FIG. 2B). As a result, the light from the rear side (specifically, the backlight 40) is attenuated on the high polar angle side, and it is possible to transmit the light from the rear side with its original luminance only on the low polar angle side, thereby realizing a narrow viewing angle mode.

[0044] As described above, the liquid crystal panel 20 of the present embodiment has a function of controlling the viewing angle by applying or not applying a voltage, and in addition to this function, it also has a louver function. Therefore, compared with a comparative image display device 1R (see Figs. 20A and 20B) that is provided with a liquid crystal panel 20R and a louver layer 30R separately, the present embodiment can reduce the thickness, weight, and manufacturing costs of the liquid crystal panel and the image display device provided with it.

[0045] The overlapping region 241 is a region of the liquid crystal layer 240 that overlaps with the second electrode 232. Overlapping with the second electrode 232 means directly or indirectly contacting the second electrode 232. An example of an indirect contact with the second electrode 232 is a region where the overlapping region 241 and the second electrode 232 are in contact with each other via an alignment film. The alignment film is a film that has a function of controlling the alignment of liquid crystal molecules contained in the liquid crystal layer 240. On the other hand, the non-overlapping region 242 is a region of the liquid crystal layer 240 that does not overlap with the second electrode 232.

[0046] The thickness D of the non-overlapping region 242 is preferably, for example, 100 μm or less. More preferably, it is 50 μm or less, even more preferably, it is 30 μm or less, particularly preferably, it is 20 μm or less, and most preferably, it is 10 μm or less. In this way, the liquid crystal panel of this embodiment is compatible with normal liquid crystal processes (generally within 10 μm) and has excellent viewing angle performance. The lower limit of the thickness is not particularly limited, but, for example, it is preferably 1 μm or more.

[0047] The thickness of the non-overlapping region 242 is also referred to as the height of the non-overlapping region 242. The thickness of the non-overlapping region 242 corresponds to the distance D between the first electrode 231 and the interlayer insulating film 250 in FIG.

[0048] It is preferable that the pitch of the non-overlapping regions 242 is smaller than the pixel pitch of the display panel 10. This makes it possible to sufficiently suppress the occurrence of moire. In particular, it is preferable that the pixel pitch of the display panel 10 is an integer multiple of the pitch of the non-overlapping regions 242. It is more preferable that the pixel pitch is 1 to 50 times, and even more preferably 6 to 24 times, the pitch of the non-overlapping regions.

[0049] The width W1 of the non-overlapping region 242 and the width W2 of the overlapping region 241 can be appropriately set according to a desired viewing angle. For example, the ratio thereof (W1 / W2) may be 100 / 1 to 500, or 100 / 50 to 300.

[0050] The viewing angle θ of the liquid crystal panel 20 in the narrow viewing angle mode can be set arbitrarily by the thickness D and width W1 of the non-overlapping area 242. Specifically, the viewing angle θ can be set arbitrarily by the following formula (1): θ=2tan -1 (W1 / D) (1) It can be set by:

[0051] As described above, the liquid crystal panel 20 of this embodiment is compatible with normal liquid crystal processes (generally within 10 μm), and therefore can easily realize a narrow viewing angle mode and has excellent viewing angle performance. In this embodiment, the transparent region 244 and the switching region 243 are not physically distinguished by material, but are distinguished by the design of the power supply (for example, the arrangement of electrodes, etc.). The transparent region 244 and the switching region 243 are formed of the same material. Therefore, in this embodiment, a UV curing process for fixing the transparent region in advance in a transparent state (transparent region) during manufacturing, as shown in, for example, FIG. 11 of Patent Document 1, is not required. Therefore, the liquid crystal panel 20 of this embodiment is also advantageous in that it can simplify the manufacturing process of liquid crystal panels and image display devices. The liquid crystal panel 20 of this embodiment will be further described below.

[0052] The first transparent substrate 210 and the second transparent substrate 220 may be any substrate that is transparent to visible light, such as a glass substrate or a plastic substrate.

[0053] The first electrode 231 is disposed in a planar manner on the entire surface of the first transparent substrate 210. In other words, the first electrode 231 is a solid electrode that covers the first transparent substrate 210. This allows the entire liquid crystal panel to switch between a wide viewing angle mode and a narrow viewing angle mode. The first electrode 231 may be a transparent electrode. The transparent electrode may be formed of, for example, a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or tin oxide (SnO), or an alloy thereof.

[0054] The second electrodes 232 are arranged at intervals so that the liquid crystal layer 240 can be divided into an overlapping region 241 that overlaps with the second electrode and a non-overlapping region 242 that does not overlap with the second electrode. In this embodiment, as shown in FIG. 7, the second electrodes 232 are arranged in a stripe shape (also called a slit shape) in a plan view. By arranging them in this manner, it is possible to control the viewing angle in the left-right direction of the screen. In this embodiment, a transparent electrode is used as the second electrode 232. Examples of the transparent electrode are as described above.

[0055] In this embodiment, the third electrode 233 is disposed in a planar manner on the entire surface of the second transparent substrate 220. In other words, the third electrode 233 is a solid electrode that covers the second transparent substrate 220. The third electrode 233 may be a transparent electrode. Examples of the transparent electrode are as described above.

[0056] In this embodiment, the liquid crystal layer 240 includes PDLC. PDLC includes a polymer network and a liquid crystal component. In PDLC, a fibrous matrix of a cured product of a photopolymerizable liquid crystal compound is aggregated to form a three-dimensionally continuous polymer network, and the liquid crystal component is in a phase-separated state in the polymer network.

[0057] The photopolymerizable liquid crystal compound for forming a polymer network is, for example, one that exhibits a liquid crystal phase at room temperature and is compatible with the liquid crystal component, and undergoes phase separation from the liquid crystal component when cured by irradiation with ultraviolet light to form a polymer.

[0058] Specific examples of photopolymerizable liquid crystal compounds include monomers having a substituent (also referred to as a "mesogen group") such as a biphenyl group, a terphenyl group, a naphthalene group, a phenylbenzoate group, an azobenzene group, and derivatives thereof; a photoreactive group such as a cinnamoyl group, a chalcone group, a cinnamylidene group, a β-(2-phenyl)acryloyl group, a cinnamic acid group, and derivatives thereof; and a polymerizable group such as an acrylate, a methacrylate, a maleimide, an N-phenylmaleimide, or a siloxane. Among these, acrylate is preferred. The number of polymerizable groups per molecule of the photopolymerizable liquid crystal compound is not particularly limited, but is preferably one or two.

[0059] The liquid crystal component does not need to have a polymerizable group such as acrylate, methacrylate, maleimide, N-phenylmaleimide, or siloxane.

[0060] In this embodiment, the liquid crystal component (also referred to as liquid crystal molecule) may have a positive or negative dielectric anisotropy (Δε) defined by the following formula (L). A liquid crystal component having a positive dielectric anisotropy is aligned parallel to the electric field direction, and a liquid crystal component having a negative dielectric anisotropy is aligned perpendicular to the electric field direction. A liquid crystal component having a positive dielectric anisotropy is also called a positive type liquid crystal, and a liquid crystal component having a negative dielectric anisotropy is also called a negative type liquid crystal. The long axis direction of the liquid crystal component is the direction of the slow axis. The direction of the long axis of the liquid crystal component when no voltage is applied is also called the initial alignment direction of the liquid crystal component. Δε = (dielectric constant of the liquid crystal component in the long axis direction) - (dielectric constant of the liquid crystal component in the short axis direction) (L)

[0061] As the liquid crystal component, for example, a tolan-based liquid crystal material (a liquid crystal material having -C≡C- (carbon-carbon triple bond) as a linking group) can be used.

[0062] The refractive index anisotropy Δn of the liquid crystal component is preferably 0.18 or more and 0.24 or less, the dielectric anisotropy Δε of the liquid crystal component is preferably 15 or more and 25 or less, and the rotational viscosity γ1 of the liquid crystal component is preferably 100 mPa·s or more and 300 mPa·s or less. By adopting such an embodiment, it is possible to achieve both strong scattering and low voltage driving, and to realize a response speed equivalent to that of a normal image display device that does not contain a polymer network. By having the refractive index anisotropy Δn, the dielectric anisotropy Δε, and the rotational viscosity γ1 of the liquid crystal component all within the above ranges, such effects can be effectively realized.

[0063] A specific example of the tolan-based liquid crystal material is a liquid crystal material having a structure represented by the following general formula (L1).

[0064] [ka] (In the above formula, Q1 and Q2 each independently represent an aromatic ring group, X represents a fluorine group or a cyano group, and n1 and n2 each independently represent 0 or 1.)

[0065] In the above general formula (L1), n1 and n2 cannot simultaneously be 0. That is, the sum of n1 and n2 is 1 or 2.

[0066] The aromatic ring group in the above general formula (L1) may have a substituent.

[0067] In the above general formula (L1), Q1 and Q2 each preferably independently represent any one of the structures of the following general formulae (L2-1) to (L2-7).

[0068] [ka]

[0069] Specific examples of the liquid crystal material having the structure represented by the above general formula (L1) include structures represented by the following chemical formulas (L1-1) to (L1-21).

[0070] [ka]

[0071] The weight ratio of the liquid crystal component to the polymer network is preferably 90 / 10 to 97 / 3. That is, the weight ratio of the liquid crystal component is 90 or more and 97 or less, and when the weight ratio of the liquid crystal component is 90 or more, the weight ratio of the polymer network is 10 or less, and when the weight ratio of the liquid crystal component is 97 or less, the weight ratio of the polymer network is 3 or more. By adopting such an embodiment, it becomes possible to effectively achieve both strong scattering and low voltage drive. When the weight ratio of the polymer network exceeds 10, strong scattering is obtained but the drive voltage becomes high, and when the weight ratio of the polymer network is less than 3, the drive voltage is suppressed but strong scattering may not be obtained.

[0072] The interlayer insulating film 250 may be an organic insulating film, an inorganic insulating film, or a laminate of an organic insulating film and an inorganic insulating film. The organic insulating film may be, for example, an organic film (relative dielectric constant ε=2 to 5) of acrylic resin, polyimide resin, novolac resin, or a laminate of these. The thickness of the organic insulating film is not particularly limited, but is, for example, 2 μm or more and 4 μm or less. The inorganic insulating film may be, for example, an inorganic film (relative dielectric constant ε=5 to 7) of silicon nitride (SiNx), silicon oxide (SiO2), or a laminate of these. The thickness of the inorganic insulating film is not particularly limited, but is, for example, 1500 Å or more and 3500 Å or less.

[0073] The thickness of the interlayer insulating film 250 is preferably 0.1 μm or more and 4 μm or less, and more preferably 0.15 μm or more and 0.35 μm or less.

[0074] In the following, an image display device including the liquid crystal panel 20 of this embodiment will be described as an example. Fig. 4 is a schematic cross-sectional view of the image display device of this embodiment. Fig. 5A is a schematic cross-sectional view illustrating the image display device of this embodiment in a wide viewing angle mode. Fig. 5B is a schematic cross-sectional view illustrating the image display device of this embodiment in a narrow viewing angle mode.

[0075] As shown in Figures 4, 5A and 5B, the image display device 1 of this embodiment includes the liquid crystal panel 20 of this embodiment and a display panel 10 that displays an image. This makes it possible to realize an image display device that can control the viewing angle while keeping the thickness low. The image display device 1 of this embodiment further includes a backlight 40. In this embodiment, it is possible to realize an image display device that can display an image on the display panel 10 using light from the backlight 40 and can control the viewing angle while keeping the thickness low.

[0076] The display panel 10 may be any panel that has a function of displaying an image. The display panel 10 is capable of turning on and off image display. In this embodiment, a case where the display panel 10 is a liquid crystal display panel will be described as an example.

[0077] As shown in FIG. 4, the image display device 1 includes a display panel 10, a liquid crystal panel 20, and a backlight 40, in this order from the observation surface side to the rear surface side. The display panel 10 includes a polarizing plate 140, a CF substrate 110 including a color filter (CF) layer, a liquid crystal layer 130, a TFT substrate 120 including a thin film transistor (TFT), and the polarizing plate 140, in this order from the observation surface side to the rear surface side. An adhesive layer 150 for attaching the display panel 10 and the liquid crystal panel 20 is usually provided between the display panel 10 and the liquid crystal panel 20. In this embodiment, the display panel 10 functions as a liquid crystal display panel, and therefore the image display device of this embodiment is a liquid crystal display device. In FIG. 5A and FIG. 5B, the display panel 10 does not include the liquid crystal layer 130, but the display panel 10 may include the liquid crystal layer 130 as in FIG. 4.

[0078] The TFT substrate 120 has an insulating substrate, and in the display region, on the insulating substrate, there are provided a plurality of gate lines extending parallel to each other, and a plurality of source lines extending parallel to each other in a direction intersecting each gate line via an insulating film. The plurality of gate lines and the plurality of source lines are formed in a lattice shape as a whole so as to partition each pixel. Thin film transistors are disposed as switching elements at the intersections of each source line and each gate line.

[0079] The TFT substrate 120 has a planar common electrode arranged on the surface of the insulating substrate facing the liquid crystal layer 130, an insulating film covering the common electrode, and a pixel electrode having a slit arranged on the surface of the insulating film facing the liquid crystal layer. The pixel electrode is arranged in each region surrounded by two adjacent source lines and two adjacent gate lines, and the pixel electrode is electrically connected to the corresponding source line via a semiconductor layer provided in the thin film transistor. That is, the display panel 10 of this embodiment is a liquid crystal display panel in FFS (Fringe Field Switching) mode. The arrangement of the common electrode and the pixel electrode may be interchanged. In that case, a common electrode having a slit is arranged on a planar pixel electrode formed so as to occupy each pixel region, via an insulating film.

[0080] In this embodiment, a display panel 10 in a horizontal alignment mode in which a pixel electrode and a common electrode are provided on one of the substrates will be described, but the display mode of the display panel 10 is not limited thereto, and may be a vertical alignment mode in which a pixel electrode is provided on the TFT substrate 120 and a common electrode is provided on the CF substrate 110. The horizontal alignment mode refers to a mode in which liquid crystal molecules are aligned in a direction approximately horizontal to each of the main surfaces of a pair of substrates when no voltage is applied to the liquid crystal layer, and examples of the horizontal alignment mode include the above-mentioned FFS mode and the IPS (In-Plane Switching) mode. The vertical alignment mode refers to a mode in which liquid crystal molecules are aligned in a direction approximately vertical to each of the main surfaces of a pair of substrates when no voltage is applied to the liquid crystal layer, and examples of the VA (Vertical Alignment) mode and the TN (Twisted Nematic) mode are included.

[0081] Between the TFT substrate 120 and the liquid crystal layer 130, and between the CF substrate 110 and the liquid crystal layer 130, an alignment film having the function of controlling the alignment of the liquid crystal molecules contained in the liquid crystal layer 130 is disposed, respectively. In a no-voltage state in which no voltage is applied between the pixel electrodes and the common electrode, the liquid crystal molecules contained in the liquid crystal layer 130 are aligned approximately horizontally with respect to each of the main surfaces of the pair of substrates.

[0082] The display panel 10 further includes a source driver electrically connected to the source lines, a gate driver electrically connected to the gate lines, and a controller. The gate driver sequentially supplies scanning signals to the gate lines under the control of the controller. The source driver supplies data signals to the source lines under the control of the controller at the timing when the TFTs are in a voltage applied state by the scanning signal. Each pixel electrode is set to a potential according to the data signal supplied through the corresponding TFT, and a fringe field is generated between the pixel electrode and the common electrode, causing the liquid crystal molecules in the liquid crystal layer to rotate. In this way, the magnitude of the voltage applied between the pixel electrode and the common electrode is controlled to change the retardation of the liquid crystal layer, thereby controlling the transmission or non-transmission of light.

[0083] The CF substrate 110 may be one generally used in the field of liquid crystal display panels, and may be configured such that, for example, members such as a color filter and a black matrix (BM) layer are arranged on the surface of a transparent substrate such as a glass substrate. More specifically, the CF substrate 110 includes a black matrix arranged in a lattice shape on an insulating substrate so as to correspond to gate lines and source lines, color filters of multiple colors including red layers, green layers, and blue layers arranged periodically between the lattices of the black matrix, an overcoat layer made of a transparent insulating resin arranged to cover the black matrix and each color filter, and a photospacer arranged in a columnar shape on the overcoat layer.

[0084] The pair of polarizing plates 140 and the adhesive layer 150 (OCA, etc.) are not particularly limited and may be those used in ordinary liquid crystal display devices, and the liquid crystal layer 130 may also be those normally used in ordinary liquid crystal display devices, so description thereof will be omitted.

[0085] The backlight 40 is not particularly limited as long as it irradiates light onto the liquid crystal panel 20. For example, the backlight 40 may have a light source and a reflective sheet. As the light source, a general backlight light source, that is, a light source such as a cold cathode fluorescent lamp (CCFL) or a light emitting diode (LED), may be used.

[0086] The backlight 40 may be of a direct type or an edge light type. In the case of an edge light type, the backlight 40 may have a light source, a reflecting sheet, and a light guide plate. The light source is disposed on an end face of the light guide plate, and the reflecting sheet is disposed on the back face of the light guide plate. The light guide plate may be one that is commonly used in the field of image display devices. Examples of the reflecting sheet include an aluminum plate, a white polyethylene terephthalate (PET) film, and a reflecting film (for example, an ESR (Enhanced Specular Reflector) film manufactured by 3M).

[0087] The image display device 1 of the present embodiment is configured with a plurality of components, such as external circuits such as TCP (tape carrier package) and PCB (printed wiring board), optical films such as viewing angle widening film and brightness enhancement film, and bezel (frame), in addition to the above-mentioned components, and some components may be incorporated into other components. Components other than those already described are not particularly limited, and those commonly used in the field of image display devices can be used, so their description will be omitted.

[0088] (Modification of the first embodiment) In the image display device 1 of the above-mentioned embodiment 1, the display panel 10 is disposed on the observation surface side of the liquid crystal panel 20, but the display panel 10 may be disposed on the rear side of the liquid crystal panel 20. That is, as shown in Fig. 6, the image display device 1 may be configured to include, in order from the observation surface side to the rear side, the liquid crystal panel 20, the display panel 10, and a backlight 40. Fig. 6 is a schematic cross-sectional view of the image display device of this example.

[0089] (Embodiment 2) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the arrangement shape of the second electrode 232 is different.

[0090] Fig. 8 is a schematic plan view showing the arrangement of the second electrodes in the liquid crystal panel of this embodiment. In this embodiment, as shown in Fig. 8, the second electrodes 232 are arranged in a lattice shape in a plan view. In this case, it is possible to control the viewing angle not only in the left-right direction of the screen, but also in the up-down direction.

[0091] (Embodiment 3) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the position of the second electrode 232 and the design of the power supply are different.

[0092] Fig. 9 is a schematic cross-sectional view of a liquid crystal panel according to this embodiment. As shown in Fig. 9, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0093] FIG. 9(c) is a main difference from the first embodiment (FIG. 1). In the first embodiment, the switching region 243 is designed to be switched between a transparent state (see FIG. 2A) or a scattering state (see FIG. 2B) by applying or not applying a voltage between the first electrode 231 and the second electrode 232 (262). In contrast, in the present embodiment, the switching region 243 is designed to be switched between a transparent state or a scattering state by applying or not applying a voltage between the first electrode 231 and the third electrode 233 (261). In this case, in the present embodiment, the overlapping region 241 becomes the transparent region 244, and the non-overlapping region 242 becomes the switching region 243 (see FIG. 9). However, in reality, not only the non-overlapping region 242 becomes the switching region 243, but depending on the state of the electric field between the electrodes, the boundary between the overlapping region 241 and the non-overlapping region 242 may also become the switching region 243, or other parts may become the switching region 243. 9, and can be appropriately controlled by, for example, the width and pitch of the second electrode 232, the cell thickness (i.e., the thickness D of the non-overlapping region 242), the voltage applied to each electrode, etc. The same can be said for the other embodiments described below.

[0094] (Embodiment 4) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the arrangement shape of the third electrode 233 is different.

[0095] Fig. 10A is a schematic cross-sectional view showing an example of a liquid crystal panel according to this embodiment. Fig. 10B is a schematic cross-sectional view showing another example of a liquid crystal panel according to this embodiment. As shown in Figs. 10A and 10B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0096] (d) of Fig. 10A is a main difference from embodiment 1 (Fig. 1). In embodiment 1, the third electrode 233 is disposed in a planar manner over the entire surface of the second transparent substrate 220. In other words, the third electrode 233 is a so-called solid electrode. In contrast, in this embodiment, the third electrode 233 is formed by patterning.

[0097] (Modification of the fourth embodiment) In the above-mentioned embodiment 4, the switching region 243 is designed to be switched between a transmission state and a scattering or absorbing state by application or non-application of a voltage between the first electrode 231 and the second electrode 232 (262) (see FIG. 10A). This may be designed to be switched between a transmission state and a scattering or absorbing state by application or non-application of a voltage between the first electrode 231 and the third electrode 233 (261) as in the above-mentioned embodiment 3 (see FIG. 10B). In this example, since such a design is adopted (see FIG. 10B), the overlapping region 241 becomes the transparent region 244, and the non-overlapping region 242 becomes the switching region 243. However, as described above, in reality, not only the non-overlapping region 242 becomes the switching region 243, but depending on the state of the electric field between the electrodes, the boundary portion between the overlapping region 241 and the non-overlapping region 242 may also become the switching region 243, or other portions may also become the switching region 243.

[0098] (e) of Fig. 10B is a main difference from embodiment 3 (Fig. 9). In embodiment 3, similar to embodiment 1, the third electrode 233 is disposed in a planar manner over the entire surface of the second transparent substrate 220. In other words, the third electrode 233 is a so-called solid electrode. In contrast, in this embodiment, the third electrode 233 is formed by patterning.

[0099] (Embodiment 5) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that an electrode containing a light absorbing material is used as the second electrode 232.

[0100] Fig. 11A is a schematic cross-sectional view for explaining the wide viewing angle mode of the liquid crystal panel according to this embodiment. Fig. 11B is a schematic cross-sectional view for explaining the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in Figs. 11A and 11B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0101] In this embodiment, an electrode containing a light absorbing material is used as the second electrode 232. By using an electrode containing a light absorbing material, it is possible to reduce obliquely emitted light (specifically, this means light that is emitted from the liquid crystal panel 20 as oblique light), thereby further improving the narrow viewing angle performance. As the electrode containing a light absorbing material, for example, a light absorbing material electrode, a laminate of a light absorbing material layer and a transparent electrode, a laminate of a reflector and a light absorbing material electrode, a laminate of a reflector, a light absorbing material layer and a transparent electrode, etc. are preferable.

[0102] The light absorbing material, the transparent electrode, and the reflective material constituting the electrode containing the light absorbing material may be materials that are commonly used in the field of electrodes. For example, the light absorbing material may be a metal black matrix (also referred to as metal BM) made of a metal, or a resin black matrix (also referred to as resin BM) made of a resin material. The metal BM may be, for example, a metal film containing aluminum, molybdenum, chromium, titanium, or an alloy thereof, and may be a single-layer film or a multi-layer film. The resin BM may be, for example, a black resist, and among them, a black photosensitive resin is preferable. A specific example is a black photosensitive acrylic resin. The transmittance of the light absorbing material is preferably, for example, 0% or more and 1% or less.

[0103] Examples of the transparent electrode are as described above, and among them, ITO is preferable. As the reflective material, for example, highly reflective metals such as silver, aluminum, alumina, talc, titanium, and an alloy of silver, palladium, and copper (APC) can be used. Also, a dielectric multilayer film (enhanced reflection film) in which a high refractive index layer such as Ta2O3 and a low refractive index layer such as MgF2 are laminated, or a laminate of a highly reflective metal and an enhanced reflection film can be used. The reflective material can be formed, for example, by forming a metal film by a deposition method, a sputtering method, or the like, and then patterning it. The light reflectance of the reflective material is preferably, for example, 90% or more and 100% or less.

[0104] In this embodiment, a case where a light absorbing electrode is used as the second electrode 232 will be described in particular. As the light absorbing electrode, a metal BM is preferable. The metal BM is usually formed as a metal thin film of a fine pattern on a substrate. Examples of materials for the metal thin film include aluminum, molybdenum, chromium, titanium, and alloys thereof. Typical film forming methods include deposition, sputtering, and vacuum film forming. The metal thin film is patterned, for example, by applying a photoresist onto the metal thin film and drying it, irradiating it with ultraviolet light through a photomask, dissolving the unexposed parts with a developer to form a resist pattern, and then etching the metal and peeling off the resist.

[0105] In the narrow viewing angle mode (see FIG. 2B) of the first embodiment, the light (see FIG. 2B(b)) that is directly incident on the switching region 243 (scattering state) from the backlight 40 is scattered in the switching region 243 and exits the liquid crystal panel 20 as oblique light (see FIG. 2B(a)). In contrast, in the narrow viewing angle mode (see FIG. 11B) of the present embodiment, the light (see FIG. 11B(h)) that is directly incident on the switching region 243 (scattering state) from the backlight 40 is cut by the light absorbent electrode (second electrode 232), so that the light that is scattered as oblique light and exits the liquid crystal panel 20 (see FIG. 11B(g)) can be reduced. Therefore, in the present embodiment, the narrow viewing angle performance is further improved compared to the first embodiment. Note that light from the backlight 40 does not directly enter the switching region 243, but is transmitted through the Akira area 24 4Since there is light passing through the light absorbing electrode (second electrode 232) and entering the switching region 243 (i.e., light entering the switching region 243 from the backlight 40 without passing through the light absorbing electrode (second electrode 232)), even in the narrow viewing angle mode of this embodiment, there is a small amount of obliquely emitted light due to scattering of that light.

[0106] (Modification of the fifth embodiment) In the above-mentioned embodiment 5, a case has been described in which a light absorbing electrode among electrodes containing a light absorbing material is used as the second electrode 232, but a laminate of a light absorbing material layer and a transparent electrode can also be used as the second electrode 232. In this case, as in the above-mentioned embodiment 5, the narrow viewing angle performance is further improved compared to the above-mentioned embodiment 1.

[0107] The light absorbing layer is preferably a resin BM. A specific example of a laminate of a light absorbing layer and a transparent electrode is one in which a transparent electrode (ITO or the like) is laminated on a resin BM.

[0108] (Embodiment 6) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that an electrode containing a light absorbing material is used as the second electrode 232.

[0109] Fig. 12A is a schematic cross-sectional view illustrating the wide viewing angle mode of the liquid crystal panel according to this embodiment. Fig. 12B is a schematic cross-sectional view illustrating the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in Figs. 12A and 12B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0110] In this embodiment, an electrode containing a light absorbing material is used as the second electrode 232. By using an electrode containing a light absorbing material, it is possible to reduce obliquely emitted light, and therefore the narrow viewing angle performance is further improved. Among electrodes containing a light absorbing material, in this embodiment, a laminate of a reflector and a light absorbing material electrode is particularly used as the second electrode 232.

[0111] Among the above-mentioned metals, silver (Ag) is preferable as the reflective material. As the light absorbing material electrode, metal BM is preferable as described above. Therefore, as a laminate of a reflective material and a light absorbing material electrode, a laminate in which metal BM is laminated on silver is preferable. When an electrode including a reflective material is used as the second electrode 232, it is preferable to arrange the reflective material so that it is located on the backlight 40 side. In other words, when a laminate of a reflective material and a light absorbing material electrode is used, it is preferable to arrange the laminate so that the reflective material is on the backlight 40 side.

[0112] As in the above-mentioned embodiment 5, in this embodiment, the narrow viewing angle performance is further improved compared to the above-mentioned embodiment 1. However, in the embodiment 5, as a trade-off for the improvement of the narrow viewing angle performance, even in the wide viewing angle mode in which it is not necessary to cut the oblique light 1LB, the second electrode 232 (light absorbing electrode) may cut the light (see (f) of FIG. 11A). In contrast, in this embodiment, since the second electrode 232 (a laminate of a reflector and a light absorbing electrode) contains a reflector, the light incident from the backlight 40 to the overlapping region 241 (the switching region 243 of the scattering state) can be reflected to the back side (the backlight 40 side) by the reflector. Furthermore, when the backlight 40 includes a reflecting sheet, the reflected light from the reflector can be reflected again to the observation surface side by the reflecting sheet, and recycled as the light incident to the non-overlapping region 242 (the transparent region 244) (see (i) of FIG. 12A). As a result, it is possible to cut off the light that is directly incident on the overlapping region 241 (the scattering state switching region 243) that is to be cut off in the narrow viewing angle mode, while changing (recycling) the light into the front direction without absorbing it and wasting it. Therefore, in this embodiment, it is possible to increase the brightness in both the wide viewing angle mode and the narrow viewing angle mode.

[0113] (Modification of the sixth embodiment) In the above-described sixth embodiment, a laminate of a reflector and a light absorbing electrode among electrodes containing a light absorbing material is used as the second electrode 232, but a laminate of a reflector, a light absorbing material layer, and a transparent electrode can also be used as the second electrode 232. In this modified example, similarly to the sixth embodiment, the narrow viewing angle performance is further improved, and since the second electrode 232 contains a reflector, the luminance can be increased in both the wide viewing angle mode and the narrow viewing angle mode.

[0114] As described above, silver (Ag) is preferable as the reflective material. As described above, resin BM is preferable as the light absorbing material layer. Therefore, as a laminate of a reflective material, a light absorbing material layer, and a transparent electrode, a laminate in which resin BM and a transparent electrode (ITO, etc.) are laminated on silver is preferable. In this case, it is also preferable to arrange the laminate so that the reflective material is on the backlight 40 side.

[0115] (Embodiment 7) In this embodiment, the characteristics unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the liquid crystal layer 240 is a PDLC that scatters when a voltage is applied.

[0116] FIG. 13A is a schematic cross-sectional view for explaining the wide viewing angle mode of the liquid crystal panel according to this embodiment. FIG. 13B is a schematic cross-sectional view for explaining the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in FIG. 13A and FIG. 13B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order. In this embodiment, the electrode on the second substrate 220 side can be a single layer (only the second electrode 232), and the interlayer insulating film 250 is not required, so that the manufacturing process can be further shortened (see FIG. 13A and FIG. 13B).

[0117] As shown in FIG. 13A and FIG. 13B, light is incident on the liquid crystal panel 20 from the rear side (specifically, the backlight 40). When the liquid crystal layer 240 uses PDLC having a scattering characteristic when a voltage is applied, in a state where no voltage is applied between the first electrode 231 and the second electrode 232 (260), the overlapping area 241 and the non-overlapping area 242 are not distinguished and are integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent area) (see FIG. 13A). That is, the transparent area 244 and the switching area 243 are in a state having a transmittance T1. In this case, of the light incident on the liquid crystal panel 20 from the backlight 40, the light that is incident on the liquid crystal layer 240 without passing through the second electrode 232 passes through the liquid crystal panel 20 as it is (see FIG. 13A). As a result, it is possible to transmit light from the backlight 40 with sufficiently reduced transmission loss from the low polar angle side to the high polar angle side, so that a wide viewing angle mode can be realized with high brightness.

[0118] On the other hand, in a state where a voltage is applied between the first electrode 231 and the second electrode 232 (voltage applied state), the liquid crystal layer 240 itself acts as a louver. That is, among the light incident from the backlight 40 to the liquid crystal panel 20, the light 1LB in the oblique direction is scattered (attenuated) in the overlapping region 241 (switching region 243) and passes through the liquid crystal panel 20 as attenuated light (see FIG. 13B). Here, the overlapping region 241 (switching region 243) is in a scattering state, whereas the non-overlapping region 242 (transparent region 244) remains in a transmitting state. That is, the transparent region 244 has a transmittance T2, and the switching region 243 has a transmittance T3 due to scattering (where T1≧T2>T3). Among the light incident from the backlight 40 to the liquid crystal panel 20, the light 1LA in the front direction passes through the liquid crystal panel 20 without being attenuated (see FIG. 13B). As a result, the light from the backlight 40 is attenuated on the high polar angle side, and only on the low polar angle side, the light from the back side can be transmitted with its original brightness, thereby realizing a narrow viewing angle mode.

[0119] (Embodiment 8) In this embodiment, the characteristics unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that a PDLC that scatters when a voltage is applied is used as the liquid crystal layer 240.

[0120] Fig. 14A is a schematic cross-sectional view for explaining the wide viewing angle mode of the liquid crystal panel according to this embodiment. Fig. 14B is a schematic cross-sectional view for explaining the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in Figs. 14A and 14B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0121] In the above-mentioned embodiment 7, the electrode on the second substrate 220 side is a single layer (only the second electrode 232), and the interlayer insulating film 250 is not necessary, but as in this embodiment, the interlayer insulating film 250 and the third electrode 233 may be provided in this order from the second electrode 232 side between the second electrode 232 and the second transparent substrate 220. In this case, as described in the above-mentioned embodiment 1, different voltages can be applied to the transparent region 244 and the switching region 243, respectively, which is very useful.

[0122] (Embodiment 9) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the material of the liquid crystal layer 240 is different.

[0123] Fig. 15A is a schematic cross-sectional view for explaining the wide viewing angle mode of the liquid crystal panel according to this embodiment. Fig. 15B is a schematic cross-sectional view for explaining the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in Figs. 15A and 15B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0124] In this embodiment, the liquid crystal layer 240 contains a guest-host type liquid crystal (also referred to as a GH type liquid crystal) containing a dichroic dye. A guest-host type liquid crystal containing a dichroic dye is obtained by adding a dichroic dye (guest) to a liquid crystal material (host). The ratio of the dichroic dye (guest) is preferably 0.5 to 15 mass % with respect to the total amount of the liquid crystal layer 240 (100 mass %), more preferably 1 to 10 mass %, and further preferably 2 to 5%. The color of the dichroic dye is not particularly limited, but examples thereof include black and red.

[0125] The liquid crystal layer 240 also has an overlapping region 241 that overlaps the second electrode 232 and a non-overlapping region 242 that does not overlap the second electrode 232. Since the liquid crystal layer 240 contains GH-type liquid crystal containing a dichroic dye and has the overlapping region 241 and the non-overlapping region 242, the liquid crystal layer 240 has a transparent region 244 and a switching region 243 that switches between a transmission state and a scattering or absorbing state. Depending on the design of the power supply, the overlapping region 241 can be the switching region 243 and the non-overlapping region 242 can be the transparent region 244, or the overlapping region 241 can be the transparent region 244 and the non-overlapping region 242 can be the switching region 243. In this embodiment, the switching region 243 is designed to be switched between a transparent state and a scattering state by application or non-application of a voltage (262) between the first electrode 231 and the second electrode 232, so that the overlapping region 241 becomes the switching region 243 and the non-overlapping region 242 becomes the transparent region 244 (see Figs. 15A and 15B). However, as described above, in reality, it is not only the overlapping region 241 that becomes the switching region 243, but depending on the state of the electric field between the electrodes, the boundary portion between the overlapping region 241 and the non-overlapping region 242 may also become the switching region 243, or other portions may also become the switching region 243.

[0126] In this embodiment, the switching region 243 is a region that switches between a transmissive state and an absorptive state. The absorptive state is a state in which light is absorbed. In this embodiment, the liquid crystal layer 240 in the absorptive state is in a state similar to that of light blocking glass.

[0127] In this embodiment, as described later, in the wide viewing angle mode (see FIG. 15A), the transparent region 244 and the switching region 243 have a certain transmittance (also referred to as visible light transmittance or light transmittance) T1. On the other hand, in the narrow viewing angle mode (see FIG. 15B), the transparent region 244 has a transmittance T2, and the switching region 243 has a transmittance T3 due to absorption (where T1, T2, and T3 satisfy the relationship "T1≧T2>T3"). The transmittance T1 may be 100%. T3 may be 0%.

[0128] As shown in FIG. 15A and FIG. 15B, light is incident on the liquid crystal panel 20 from the rear side (specifically, the backlight 40). When the liquid crystal layer 240 contains GH type liquid crystal, in a state where a voltage is applied between the first electrode 231 and the second electrode 232 (262) (voltage applied state) and in a state where a voltage is applied between the first electrode 231 and the third electrode 233 (261), the overlapping area 241 and the non-overlapping area 242 are not distinguished but are integrated, and the entire liquid crystal layer 240 is in a transmissive state (transparent area) (see FIG. 15A). That is, the transparent area 244 and the switching area 243 are in a state having a transmittance T1. In this case, of the light incident on the liquid crystal panel 20 from the backlight 40, the light that is incident on the liquid crystal layer 240 without passing through the second electrode 232 passes through the liquid crystal panel 20 as it is (see FIG. 15A). As a result, it is possible to transmit light from the backlight 40 with sufficiently reduced transmission loss from the low polar angle side to the high polar angle side, so that a wide viewing angle mode can be realized with high brightness.

[0129] On the other hand, in a state where no voltage is applied between the first electrode 231 and the second electrode 232 (262) (voltage non-application state) and a voltage is applied between the first electrode 231 and the third electrode 233 (261), the liquid crystal layer 240 itself acts as a louver. That is, among the light incident on the liquid crystal layer 240 from the backlight 40, the oblique light 1LB is absorbed (attenuated) in the overlapping region 241 (switching region 243) and passes through the liquid crystal panel 20 as attenuated light (see FIG. 15B). Here, the overlapping region 241 (switching region 243) is in an absorbing state, whereas the non-overlapping region 242 (transparent region 244) remains in a transmitting state. That is, the transparent region 244 has a transmittance T2, and the switching region 243 has a transmittance T3 due to absorption (where T1≧T2>T3). Of the light incident on the liquid crystal panel 20 from the backlight 40, the light 1LA in the front direction passes through the liquid crystal panel 20 without attenuation (see FIG. 15B). As a result, the light from the backlight 40 is attenuated on the high polar angle side, and it is possible to transmit the light from the back side with the same luminance only on the low polar angle side, thereby realizing a narrow viewing angle mode.

[0130] (Modification of the 9th embodiment) In the above-mentioned ninth embodiment, an example has been described in which GH type liquid crystal containing a dichroic dye is used as the liquid crystal layer 240, but it is also possible to use PDLC containing a dichroic dye as the liquid crystal layer 240.

[0131] 15A and 15B are schematic cross-sectional views for explaining the wide viewing angle mode of the liquid crystal panel according to this embodiment, and schematic cross-sectional views for explaining the narrow viewing angle mode of the liquid crystal panel according to this embodiment. As shown in Fig. 15A and Fig. 15B, the liquid crystal panel 20 of this embodiment includes a first transparent substrate 210, a first electrode 231, a liquid crystal layer 240, a second electrode 232, and a second transparent substrate 220 in this order, and further includes an interlayer insulating film 250 and a third electrode 233 between the second electrode 232 and the second transparent substrate 220 in this order from the second electrode 232 side.

[0132] In this embodiment, the liquid crystal layer 240 includes PDLC containing a dichroic dye, that is, the liquid crystal layer 240 is mainly composed of PDLC containing a dichroic dye.

[0133] The liquid crystal layer 240 of the liquid crystal panel 20 of the present invention may be in any of the following forms: a form including PDLC (see, for example, embodiments 1 to 8 and the modified examples of embodiment 9); a form including GH type liquid crystal (see, for example, embodiment 9); and a form including both PDLC and GH type liquid crystal.

[0134] (Embodiment 10) In this embodiment, the features unique to this embodiment will be mainly described, and the description of the contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that a backlight driven by local dimming is used as the backlight 40.

[0135] 4, 5A, and 5B are respectively a cross-sectional view of the image display device of this embodiment, a cross-sectional view explaining the wide viewing angle mode of the image display device of this embodiment, and a cross-sectional view explaining the narrow viewing angle mode of the image display device of this embodiment. In this embodiment, a backlight driven by local dimming is used as the backlight 40.

[0136] Local dimming drive is a function that divides the image display area of ​​a display device into multiple areas (also called segments) and controls the light for each area. By using a backlight with local dimming drive, the brightness of the backlight can be controlled locally, thereby realizing a display device with high contrast and low power consumption. However, in general, in a display device that controls the viewing angle by the backlight, it is difficult to achieve both viewing angle control and local dimming drive. In contrast, in the present invention, the viewing angle can be controlled by the liquid crystal panel 20, so the backlight drive method is not limited. Therefore, it is possible to combine the liquid crystal panel 20 with a backlight with local dimming drive, which is very useful.

[0137] (Embodiment 11) In this embodiment, the features unique to this embodiment will be mainly described, and descriptions of contents overlapping with the above-mentioned embodiment 1 will be omitted. This embodiment is substantially the same as embodiment 1, except that the display panel 10 is a self-luminous display panel.

[0138] Fig. 16 is a schematic cross-sectional view of an image display device according to this embodiment. As shown in Fig. 16, the image display device 1 of this embodiment includes the liquid crystal panel 20 of this embodiment and a self-luminous display panel as the display panel 10 that displays an image. An adhesive layer 150 is usually provided between the display panel 10 and the liquid crystal panel 20 to attach them together. Since the image display device of this embodiment has a self-luminous display panel as the display panel 10, a backlight is not required.

[0139] The self-luminous display panel is not particularly limited as long as it is a self-luminous display panel. For example, an organic electroluminescence (EL) type display panel and a Micro-LED type display panel using micrometer (μm)-sized LEDs as RGB elements can be mentioned. In the present invention, the viewing angle can be controlled by the liquid crystal panel 20 regardless of the presence or absence of a backlight. Therefore, the liquid crystal panel 20 can be combined with a self-luminous display panel, which is very useful.

[0140] Although the embodiments of the present invention have been described above, the individual matters described above can all be applied to the present invention as a whole.

[0141] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0142] Example 1 The image display device of Example 1 corresponds to the image display device of the above-mentioned embodiment 1 (see Figs. 4, 5A, 5B and 7). The size of the display panel 10 was set to 11 inches, the resolution to FHD, and the pixel pitch (pixel width in the extension direction of the gate line x pixel width in the extension direction of the source line) to 42 µm x 126 µm. Various design values ​​of the liquid crystal panel 20 are shown in Table 1. In the examples described later, the same display panel 10 and backlight 40 as those of Example 1 were used unless otherwise specified. Various designs and structures of the liquid crystal panel 20 are also the same as those of Example 1 unless otherwise specified.

[0143] [Table 1]

[0144] Fig. 17A is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this embodiment. Fig. 17B is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this embodiment. A (231) is a waveform diagram of the voltage of the first electrode 231, B (233) is a waveform diagram of the voltage of the third electrode 233, and C (232) is a waveform diagram of the voltage of the second electrode 232. The horizontal axis indicates time, and the vertical axis indicates voltage (V). The driving voltage is not limited to this voltage setting, and may be set as appropriate.

[0145] In this embodiment, the first electrode 231(A) functions as a common electrode, the first electrode 231(A) and the third electrode 233(B) control the non-overlapping area 242 (mainly the transparent area 244), and the first electrode 231(A) and the second electrode 232(C) control the overlapping area 241 (mainly the switching area 243).

[0146] The image display device of this embodiment is compatible with normal liquid crystal processes, does not generate moire, and has excellent viewing angle performance. In particular, it can realize a wide viewing angle mode with high brightness, and it is possible to reduce the thickness, weight, and manufacturing cost of the image display device.

[0147] Example 2 The image display device of Example 2 corresponds to the image display device of the above-mentioned embodiment 2. It is the same as the above-mentioned example 1, except that the arrangement of the second electrodes 232 is changed to a lattice shape (plan view) as shown in Fig. 8. In the image display device of this example, it was possible to control the viewing angle not only in the left-right direction of the screen, but also in the up-down direction.

[0148] Example 3 The image display device of Example 3 corresponds to the image display device of the above-mentioned embodiment 3 (see FIG. 9). In this example, the switching region 243 is designed to be switched between a transparent state and a scattering state by application or non-application of a voltage (261) between the first electrode 231 and the third electrode 233. In this example, the overlapping region 241 mainly becomes the transparent region 244, and the non-overlapping region 242 mainly becomes the switching region 243.

[0149] (Examples 4-1 and 4-2) The image display device of Example 4-1 corresponds to the image display device of the above-mentioned embodiment 4 (see FIG. 10A), and the image display device of Example 4-2 corresponds to the image display device of a modified example of the above-mentioned embodiment 4 (see FIG. 10B). The third electrode 233 was formed by patterning, as shown in (d) of FIG. 10A and (e) of FIG. 10B.

[0150] The image display device of this embodiment is also compatible with normal liquid crystal processes, does not generate moire, and has excellent viewing angle performance. In particular, it is possible to realize a wide viewing angle mode with high brightness, and it is also possible to reduce the thickness, weight, and manufacturing cost of the image display device.

[0151] Example 5 The image display device of Example 5 corresponds to the image display device of the above-mentioned embodiment 5 (see FIGS. 11A and 11B). In this example, a light absorbing electrode (metal BM) was used as the second electrode 232. In this example, the narrow viewing angle performance was further improved compared to Example 1.

[0152] Example 6 The image display device of Example 6 corresponds to the image display device of the above-mentioned embodiment 6 (see Figs. 12A and 12B). In this example, a laminate of a reflector and a light absorbing electrode was used as the second electrode 232. In this example, the luminance was further improved in both the wide viewing angle mode and the narrow viewing angle mode compared to Example 1.

[0153] Example 7 The image display device of Example 7 corresponds to the image display device of the above-mentioned embodiment 7 (see Figs. 13A and 13B). Fig. 18A is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this example. Fig. 18B is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this example. A (231) is a waveform diagram of the voltage of the first electrode 231, and B (232) is a waveform diagram of the voltage of the second electrode 232. The horizontal axis indicates time, and the vertical axis indicates voltage (V). The driving voltage is not limited to this voltage setting, and may be set as appropriate.

[0154] In this embodiment, the first electrode 231(A) functions as a common electrode, and the overlapping region 241 (mainly the switching region 243) is controlled by the first electrode 231(A) and the second electrode 232(C).

[0155] In this embodiment, the third electrode and the interlayer insulating film are not necessary, and the manufacturing process can be further shortened.

[0156] Example 8 The image display device of Example 8 corresponds to the image display device of the above-mentioned embodiment 8 (see Figs. 14A and 14B). Fig. 19A is a waveform diagram of the voltage of each electrode in the wide viewing angle mode in the image display device of this example. Fig. 19B is a waveform diagram of the voltage of each electrode in the narrow viewing angle mode in the image display device of this example. A (231) is a waveform diagram of the voltage of the first electrode 231, B (233) is a waveform diagram of the voltage of the third electrode 233, and C (232) is a waveform diagram of the voltage of the second electrode 232. The horizontal axis indicates time, and the vertical axis indicates voltage (V). The driving voltage is not limited to this voltage setting, and is set appropriately.

[0157] In this embodiment, the first electrode 231(A) functions as a common electrode, the first electrode 231(A) and the third electrode 233(B) control the non-overlapping area 242 (mainly the transparent area 244), and the first electrode 231(A) and the second electrode 232(C) control the overlapping area 241 (mainly the switching area 243).

[0158] (Examples 9-1 and 9-2) The image display device of Example 9-1 corresponds to the image display device of the above-mentioned embodiment 9, and the image display device of Example 9-2 corresponds to the image display device of a modified example of the above-mentioned embodiment 9 (see FIGS. 15A and 15B for both examples).

[0159] The image display device of this embodiment is also compatible with normal liquid crystal processes, does not generate moire, and has excellent viewing angle performance. In particular, it is possible to realize a wide viewing angle mode with high brightness, and it is also possible to reduce the thickness, weight, and manufacturing cost of the image display device.

[0160] Example 10 The image display device of Example 10 corresponds to the image display device of the above-mentioned embodiment 10. For the structure of the image display device and the path of light in each viewing angle mode, see Fig. 4, Fig. 5A, Fig. 5B and Fig. 7. Even when a backlight driven by local dimming is combined as in this example, it is possible to realize an image display device with excellent viewing angle performance while suppressing thickness, weight and manufacturing costs.

[0161] Example 11 The image display device of Example 11 corresponds to the image display device of the above-mentioned embodiment 11 (see FIG. 16). Even when combined with a self-luminous display panel as in this example, an image display device with excellent viewing angle performance was realized while suppressing thickness, weight, and manufacturing costs.

[0162] The above-described aspects of the present invention may be combined as appropriate without departing from the gist of the present invention. [Explanation of symbols]

[0163] 1, 1R: Video display device 1LA: Front light 1LB: Oblique light 10: Display panel 20, 20R: LCD panel 30R: Louver layer 40: Backlight 110: Color filter (CF) substrate 120: Thin film transistor (TFT) substrate 130: Liquid crystal layer 140: Polarizing plate 150: Adhesive layer 210: First transparent substrate 220: Second transparent substrate 230: Electrode 231: First electrode 232: Second electrode 233: Third electrode 240, 240R: Liquid crystal layer 241: Overlapping area 242: Non-overlapping area 243: Switching area 244 :Transparent area 250: Interlayer insulating film 260, 261, 262: Power supply

Claims

1. A liquid crystal panel comprising, in this order, a first transparent substrate, a first electrode, a liquid crystal layer, a second electrode, and a second transparent substrate, The liquid crystal layer contains a polymer dispersed liquid crystal and / or a guest-host type liquid crystal containing a dichroic dye, and has an overlapping region that overlaps the second electrode and a non-overlapping region that does not overlap the second electrode, thereby causing the liquid crystal layer to have a transparent region and a switching region that switches between a transmissive state and a scattering or absorbing state.

2. 2. The liquid crystal panel according to claim 1, wherein the second electrodes are arranged in a stripe pattern or a lattice pattern in a plan view.

3. 2. The liquid crystal panel according to claim 1, further comprising an interlayer insulating film and a third electrode, in this order, between the second electrode and the second transparent substrate, from the second electrode side.

4. 4. The liquid crystal panel according to claim 3, wherein different voltages can be applied to the transparent region and the switching region.

5. 2. The liquid crystal panel according to claim 1, wherein the non-overlapping region has a thickness of 30 [mu]m or less.

6. 2. The liquid crystal panel according to claim 1, wherein the second electrode is a transparent electrode or an electrode containing a light absorbing material.

7. 7. A video display device comprising the liquid crystal panel according to claim 1 and a display panel for displaying an image.

8. 8. The image display device according to claim 7, further comprising a backlight.

9. 9. The image display device according to claim 8, wherein the backlight has a local dimming function.

10. 8. The image display device according to claim 7, wherein the display panel is a liquid crystal display panel or a self-luminous display panel.

Images