Liquid crystal panel and display device

According to an aspect, a liquid crystal panel includes: a first substrate that is a light-transmitting substrate; a second substrate that is disposed facing the first substrate with a liquid crystal interposed between the first substrate and the second substrate and is a light-transmitting substrate; a wiring layer provided on the first substrate on a side facing the liquid crystal and comprising a plurality of wiring lines arrayed in a predetermined direction; an insulating layer stacked on the wiring layer on a side facing the liquid crystal; a first electrode layer stacked on the insulating layer on a side facing the liquid crystal; and a second electrode layer provided on the second substrate on a side facing the liquid crystal. A sheet resistance of the first electrode layer is higher than a sheet resistance of the wiring layer and a sheet resistance of the second electrode layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority from Japanese Patent Application No. 2022-092569 filed on Jun. 7, 2022, the entire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

What is disclosed herein relates to a liquid crystal panel and a display device.

2. Description of the Related Art

As described in Japanese Patent Application Laid-open Publication No. 2021-081465, it is known that there is a viewing angle control panel provided to a display surface of a display panel to control the viewing angle so as to inhibit an image on the display panel from being visually recognized when viewed obliquely.

When an image output from the display panel is viewed by a user from an oblique viewpoint, the inclination angle with respect to the display panel differs between the line of sight to a near side positioned relatively close to the display panel and the line of sight to a far side positioned relatively far from the display panel. Therefore, the image cannot be obliquely viewed on one of the near side and the far side but may possibly be obliquely viewed on the other side depending on the viewing angle characteristics of the viewing angle control panel.

For the foregoing reasons, there is a need for a liquid crystal panel and a display device that can more reliably inhibit an image from being visually recognized from an oblique viewpoint.

SUMMARY

According to an aspect, a liquid crystal panel includes: a first substrate that is a light-transmitting substrate; a second substrate that is disposed facing the first substrate with a liquid crystal interposed between the first substrate and the second substrate and is a light-transmitting substrate; a wiring layer provided on the first substrate on a side facing the liquid crystal and comprising a plurality of wiring lines arrayed in a predetermined direction; an insulating layer stacked on the wiring layer on a side facing the liquid crystal; a first electrode layer stacked on the insulating layer on a side facing the liquid crystal; and a second electrode layer provided on the second substrate on a side facing the liquid crystal. A sheet resistance of the first electrode layer is higher than a sheet resistance of the wiring layer and a sheet resistance of the second electrode layer.

DETAILED DESCRIPTION

Exemplary embodiments according to the present disclosure are described below with reference to the accompanying drawings. What is disclosed herein is given by way of example only, and appropriate modifications made without departing from the spirit of the present invention and easily conceivable by those skilled in the art naturally fall within the scope of the present disclosure. To simplify the explanation, the drawings may possibly illustrate the width, the thickness, the shape, and other elements of each component more schematically than the actual aspect. These elements, however, are given by way of example only and are not intended to limit interpretation of the present disclosure. In the present specification and the figures, components similar to those previously described with reference to previous figures are denoted by the same reference numerals, and detailed explanation thereof may be appropriately omitted.

FIG.1is a schematic sectional view of the main configuration of a viewing angle control panel1. The viewing angle control panel1includes substrates10and20and a liquid crystal30. The substrate10and the substrate20face each other with the liquid crystal30interposed therebetween. The liquid crystal30is sealed by a sealing member, which is not illustrated, provided to the outer end of the viewing angle control panel1. In the following description, the direction in which the substrate and the substrate20face each other is referred to as a Z-direction. One of two directions along a plane orthogonal to the Z-direction is an X-direction, and the other is a Y-direction. The X- and Y-directions are orthogonal to each other.

The substrate10includes a first substrate11, a wiring layer12, an insulating layer13, and a first electrode layer14. The first substrate11is a light-transmitting substrate. Specifically, the first substrate11is a glass substrate, for example, but it may be a thin-plate substrate made of other light-transmitting materials.

The wiring layer12is formed on the first substrate11on the side facing the liquid crystal30. The wiring layer12is made of light-transmitting conductive material. While the light-transmitting conductive material used for the wiring layer12is indium tin oxide (ITO), for example, it is not limited thereto and may be other light-transmitting conductive materials.

The wiring layer12includes a plurality of wiring lines arrayed in the X-direction. InFIG.1, wiring lines121,122,123, and124arrayed from one side to the other in the X-direction are illustrated as the wiring lines. The insulating layer13is interposed between the wiring lines adjacently disposed in the X-direction out of the wiring lines included in the wiring layer12. Different wiring lines of the wiring lines included in the wiring layer12are insulated in the X-direction by the insulating layer13and do not short-circuit.

A space D1in the X-direction where the insulating layer13is interposed between the wiring lines adjacently disposed in the X-direction out of the wiring lines included in the wiring layer12is preferably smaller within the region where the wiring lines adjacently disposed in the X-direction do not short-circuit. A width D2in the X-direction of each of the wiring lines included in the wiring layer12corresponds to the arrangement pitch in the X-direction of the wiring lines including the space D1. While the width D2is several millimeters (mm) to several centimeters (cm), for example, it is not limited thereto and can be appropriately changed.

FIG.3is a schematic illustrating the configuration included in the wiring layer12and the configuration coupled thereto. InFIG.3, wiring lines121,122,123, . . . , and12mare illustrated as the wiring lines included in the wiring layer12. m of the wiring line12mcorresponds to the number of wiring lines. m is a natural number. If m is 4, the wiring lines included in the wiring layer12is the wiring lines121,122,123, and124illustrated inFIG.1. In the following description, the wiring lines121, . . . , and12mrefer to the wiring lines included in the wiring layer12. The region in which the wiring lines121, . . . , and12mwith the width D2are arrayed in the X-direction with the space D1interposed therebetween described above functions as a viewing angle control region, which will be described later. In other words, the wiring lines121, . . . , and12mare disposed in the region functioning as the viewing angle control region. More specifically, the “region functioning as the viewing angle control region” corresponds to the region covered by the first electrode layer14. The wiring lines121, . . . , and12mfaces the first electrode layer14, whereby the region covered by the first electrode layer14functions as the viewing angle control region, which will be described later.

The wiring lines121, . . . , and12mare individually coupled to a drive circuit40. The drive circuit40is a circuit that can individually apply voltages to the wiring lines121, . . . , and12m. The drive circuit40is coupled to a host50via wiring, such as flexible printed circuits (FPC)45. The host50outputs commands relating to the operation of the viewing angle control panel1, such as turning on/off the operation of the viewing angle control panel1, to the drive circuit40. The drive circuit40individually applies voltages to the wiring lines121, . . . , and12min accordance with the commands.

The insulating layer13is stacked on the wiring layer12on the side facing the liquid crystal30. The insulating layer13is made of insulating material. While the insulating material used for the insulating layer13is silicon monoxide (SiO), for example, it is not limited thereto and may be silicon nitride (SiN) or other insulating resins. The use of SiO for the insulating layer13enables adjusting the electrical resistance of the first electrode layer14by adjusting the amount of oxygen supplied when the insulating layer13is formed.

The first electrode layer14is stacked on the insulating layer13on the side facing the liquid crystal30. The first electrode layer14is made of material with higher sheet resistance than the wiring layer12. Therefore, the first electrode layer14functions as a high-resistance electrode. The first electrode layer14is made of, for example, a compound containing indium, gallium, zinc, and oxygen (IGZO), indium zinc oxide (IZO), or ITO adjusted to have higher sheet resistance than the wiring layer12. The insulating layer13is interposed between the wiring layer12and the first electrode layer14. In other words, the wiring layer12and the first electrode layer14are separated by the insulating layer13.

The substrate20includes a second substrate21and a second electrode layer22. The second substrate21is a light-transmitting substrate like the first substrate11. Specifically, the second substrate21is a glass substrate, for example, but it may be a thin-plate substrate made of other light-transmitting materials.

The second electrode layer22is formed on the second substrate21on the side facing the liquid crystal30. The second electrode layer22is made of light-transmitting conductive material. The second electrode layer22has lower sheet resistance than the first electrode layer14. The light-transmitting conductive material used for the second electrode layer22is ITO, which is used for the wiring layer12, for example, but it is not limited thereto and may be other light-transmitting conductive materials.

The liquid crystal30includes a plurality of liquid crystal molecules31. The orientation of each of the liquid crystal molecules31is controlled depending on the potential difference between the electric potential of the first electrode layer14and the electric potential of the second electrode layer22. The transmittance of light traveling from one side to the other in the Z-direction in the viewing angle control panel1corresponds to the orientation of the liquid crystal molecules31. In other words, the light transmittance of the viewing angle control panel1can be controlled by controlling the potential difference between the electric potential of the first electrode layer14and the electric potential of the second electrode layer22.

The electric potential of the second electrode layer22according to the embodiment is a fixed potential. Specifically, the electric potential of the second electrode layer22is the ground potential (0 V), for example, but it is not limited thereto and can be appropriately changed. Therefore, the light transmittance of the viewing angle control panel1is controlled by controlling the electric potential of the first electrode layer14.

The electric potential of the first electrode layer14corresponds to the voltage applied to the wiring lines121, . . . , and12m. Therefore, when the voltages individually applied to the respective wiring lines121, . . . , and12mare different from each other, the electric potential of the first electrode layer14varies depending on the position in the X-direction.

FIG.2is a schematic illustrating the potential difference in regions of the first electrode layer14in the X-direction generated due to the voltages applied to a wiring line12nand a wiring line12(n+1) adjacently disposed in the X-direction. The wiring lines12nand12(n+1) are included in the wiring lines121, . . . , and12m. n is a natural number. (n+1) is equal to or smaller than m. When n=1 is satisfied, for example, the wiring lines12nand12(n+1) are the wiring lines121and122, respectively.

The electric potential of the first electrode layer14mainly corresponds to the voltage of the wiring line facing the first electrode layer14in the Z-direction out of the wiring lines included in the wiring layer12. In the example illustrated inFIG.2, the electric potential of a region V1of the first electrode layer14facing the wiring line12nin the Z-direction corresponds to the voltage of the wiring line12n. The electric potential of a region V3of the first electrode layer14facing the wiring line12(n+1) in the Z-direction corresponds to the voltage of the wiring line12(n+1).

The electric potential of a non-facing region of the first electrode layer14not facing the wiring lines included in the wiring layer12in the Z-direction and a region near the non-facing region correspond to the electric potentials of the two regions facing each other in the X-direction with the non-facing region interposed therebetween. In the example illustrated inFIG.2, a region V2of the first electrode layer14positioned between the region V1and the region V3corresponds to the non-facing region not facing the wiring lines included in the wiring layer12in the Z-direction and a region near the non-facing region. The electric potential of the region V2is an intermediate potential between the electric potentials of the regions V1and V3.

If the sheet resistance of the first electrode layer14is too low, the potential difference is not generated in the regions V1, V2, and V3, and the electric potential is constant over the entire first electrode layer14. By contrast, if the sheet resistance of the first electrode layer14is too high, the first electrode layer14functions as an insulator and is not electrically charged corresponding to the voltage applied to the wiring layer12. The sheet resistance of the first electrode layer14is adjusted such that the electric potentials of the regions V1, V2, and V3are different when the voltages of the wiring lines12nand12(n+1) are different.

Specifically, the sheet resistance of the wiring layer12and the second electrode layer22is approximately 100 Ω/sq. The sheet resistance of the first electrode layer14is approximately 104to 106Ω/sq. The resistance ratio between the sheet resistance of the first electrode layer14and the sheet resistance of the wiring layer12is preferably approximately 100:1 to 10,000:1.

The thicknesses of the wiring layer12, the insulating layer13, and the first electrode layer14in the Z-direction depend on the materials used for the wiring layer12, the insulating layer13, and the first electrode layer14, respectively. In this example, the wiring layer12is made of ITO, the insulating layer13is made of SiO, and the first electrode layer14is made of IGZO. In this case, the thickness of the wiring layer12is 70 nanometers (nm), the thickness of the insulating layer13is 200 nm, and the thickness of the first electrode layer14is 50 nm. The thickness of the insulating layer13includes the part interposed between the wiring lines adjacently disposed in the X-direction out of the wiring lines included in the wiring layer12. In other words, the thickness of the insulating layer13is the thickness between the first substrate11and the first electrode layer14.

The drive circuit40according to the embodiment described with reference toFIG.2applies different voltages to the respective wiring lines121, . . . , and12m. This configuration enables controlling the light transmittance corresponding to the difference in viewing angle between one end and the other end in the X-direction in the viewing angle control panel1when the viewing angle control panel1is viewed from a line of sight inclined in the X-direction with respect to the Z-direction.

FIG.4is a schematic of an example of the difference in viewing angle between one end and the other end in the X-direction in the viewing angle control panel1when the viewing angle control panel1is viewed from a line of sight inclined in the X-direction with respect to the Z-direction.FIG.4illustrates an example where a user H1and a user H2visually recognize a display image output by a display device100composed of a display panel60and the viewing angle control panel1stacked in the Z-direction.

The display panel60outputs an image. Specifically, the display panel60is a transmissive liquid crystal display device, for example, and outputs an image using light from a backlight provided on the side opposite to the viewing angle control panel1as a light source. The viewing angle control panel1is provided on the line of light traveling from the backlight toward the users H1and H2and controls the degree of transmission of light of the image output from the display panel60toward the users H1and H2. While the viewing angle control panel1is provided at a position between the display panel60and the users H1and H2, for example, it may be provided on the opposite side of the display panel60provided with the backlight.

A left eye EL1and a right eye ER1of the user H1are positioned side by side in the X-direction. The viewing angle control panel1and the display panel60are stacked in the Z-direction on the extension lines of a line of sight C11of the left eye EL1along the Z-direction and a line of sight C12of the right eye ER1along the Z-direction. Thus, the user H1is at a position to view the display panel60from the front through the viewing angle control panel1.

By contrast, a left eye EL2and a right eye ER2of the user H2are positioned side by side in the X-direction. The viewing angle control panel1and the display panel60are not positioned on the extension lines of a line of sight C21of the left eye EL2along the Z-direction and a line of sight C22of the right eye ER2along the Z-direction. Thus, the user H2is at a position to view the display panel60obliquely in the X-direction through the viewing angle control panel1.

There is a demand to enable an image output by the display panel60to be visually recognized by the user H1and inhibit it from being visually recognized by the user H2. In a specific example where such a demand arises, the display panel60is a display device mounted on a four-wheeled vehicle, the user H2is a driver of the four-wheeled vehicle, and the user H1is a passenger in the passenger seat of the four-wheeled vehicle. Not limited to this specific example, there is a demand to cause an image to be visually recognized only by a person, such as the user H1, who is in front of a display device, such as the display panel60, and inhibit the image from being visually recognized by a person, such as the user H2, who obliquely views the display device.

A field of view W1of the user H1extends in the X-direction so as to view the display panel60from the front through the viewing angle control panel1and has substantially no difference between the angle with respect to a first end E1and the angle with respect to a second end E2of both ends in the X-direction of an image display region in the display panel60.

By contrast, a field of view W2of the user H2has a significant difference between an angle θ1with respect to the first end E1and an angle θ2with respect to the second end E2of both ends in the X-direction of the display panel and the viewing angle control panel1. Specifically, the angle θ1with respect to the first end E1positioned relatively far from the user H2in the X-direction is significantly larger than the angle θ2with respect to the second end E2positioned relatively close to the user H2in the X-direction. If the display panel60has uniform light transmittance regardless of the position in the X-direction, the user H2having such a field of view W2cannot visually recognize an image output from the display panel60at the first end E1but may possibly be able to visually recognize it at the second end E2.

FIG.5is a view of a reference example where an image can be visually perceived as if the light transmittance differs between a far position EA and a near position EB in oblique view. InFIG.5, the liquid crystal is supplied with a uniform voltage from the far position EA to the near position EB. Therefore, a difference in light transmittance depending on the viewing angle characteristics of the panel is apparent between the far position EA and the near position EB in oblique view. Specifically, the far position EA is relatively dark because almost no light is transmitted at the far position EA, whereas light is transmitted at the near position EB by such an amount that the near position EB appears clearly brighter than the far position EA. In this reference example, the image output from the display panel60is relatively likely to be visually recognized at the near position EB.

To address this, the embodiment has a mechanism to vary the light transmittance of the viewing angle control panel1depending on the position in the X-direction. Specifically, as described with reference toFIG.3, the drive circuit40can individually apply voltages to the wiring lines121, . . . , and12m. The drive circuit40applies different voltages to the respective wiring lines121, . . . , and12m.

FIG.6is an example according to the embodiment where the light transmittance is more uniform between the far position EA and the near position EB in oblique view than in the reference example illustrated inFIG.5. In the embodiment, the brightness at the far position EA and the near position EB in oblique view is made more uniform than in the reference example. In other words, the far position EA and the near position EB according to the embodiment have almost no difference in light transmittance in oblique view. Therefore, the embodiment can reduce the occurrence of the state where the image output from the display panel can be visually recognized at the near position EB, which occurs in the reference example. The far position EA corresponds to the first end E1inFIG.4, for example. The near position EB corresponds to the second end E2inFIG.4, for example.

FIG.6illustrates an example where m=9 is satisfied in the wiring lines121, . . . , and12m, a voltage of 3.1 volts (V) is applied to the wiring line closest to the near position EB, and voltages of 3.0 V, 2.9 V, 2.8 V, 2.8 V, 2.7 V, 2.7 V, 2.6 V, and 2.5 V are applied to the other wiring lines arrayed in order from the wiring line applied with 3.1 V toward the far position EA. When the voltages of adjacent wiring lines are different, the region facing one of the adjacent wiring lines in the first electrode layer14corresponds to the region V1, the region facing the other of the adjacent wiring lines corresponds to the region V3, and the region V2between the region V1and the region V3has an intermediate potential between the electric potential of the region V1and the electric potential of the region V3as described with reference toFIG.2. The voltage of the second electrode layer22is 0 V.

To control the light transmittance, the image display region in the display panel60, that is, the region covering from the first end E1to the second end E2serves as the viewing angle control region of the viewing angle control panel1as described with reference toFIG.6. In other words, the first electrode layer14is provided in the region covering from the first end E1to the second end E2, and the wiring lines121, . . . , and12mare disposed facing the first electrode layer14.

The liquid crystal30employs what is called a twisted nematic (TN) system and is controlled so as to achieve light distribution corresponding to the potential difference between the first electrode layer14and the second electrode layer22. Although not illustrated inFIG.1and other figures, orientation films (e.g., polyimide layers) that define the initial orientation of the liquid crystal molecules31are formed on the first electrode layer14on the side facing the liquid crystal30and on the second electrode layer22on the side facing the liquid crystal30. The orientation films are provided to achieve, for example, what is called a normally white mode in which the degree of the light transmittance of the viewing angle control panel1is maximized in initial orientation of the liquid crystal molecules31with no electric field formed between the first electrode layer14and the second electrode layer22. The orientation films may be provided to achieve what is called a normally black mode in which the degree of the light transmittance of the viewing angle control panel1is minimized in initial orientation of the liquid crystal molecules31with no electric field formed between the first electrode layer14and the second electrode layer22.

As described above, the viewing angle control panel1serving as a liquid crystal panel according to the embodiment includes the first substrate11, the second substrate21, the wiring layer12, the insulating layer13, the first electrode layer14, and the second electrode layer22. The first substrate11is a light-transmitting substrate. The second substrate21is disposed facing the first substrate11with the liquid crystal30interposed therebetween and is a light-transmitting substrate. The wiring layer12is provided on the first substrate11on the side facing the liquid crystal30and includes a plurality of wiring lines arrayed in the X-direction. The insulating layer13is stacked on the wiring layer12on the side facing the liquid crystal30. The first electrode layer14is stacked on the insulating layer13on the side facing the liquid crystal30. The second electrode layer22is provided on the second substrate21on the side facing the liquid crystal30. The sheet resistance of the first electrode layer14is higher than that of the wiring layer12and that of the second electrode layer22. This configuration can form an electric field in the first electrode layer14in which the electric potential is gradually increased or decreased from one side to the other along an array direction of the wiring lines included in the wiring layer12. If a user (e.g., the user H2) obliquely views an image output from a display panel (e.g., the display panel60) through the viewing angle control panel1, the viewing angle control panel1can form a difference in light transmittance between a relatively near end (e.g., the second end E2) and a relatively far end (e.g., the first end E1) from the user, which corresponds to the difference in viewing angle from the user in the array direction. Therefore, the viewing angle control panel1can more reliably inhibit an image from being visually recognized from an oblique viewpoint.

The wiring layer12and the first electrode layer14are separated by the insulating layer13, and each of the wiring layer12, the first electrode layer14, and the second electrode layer22is a light-transmitting layer. This configuration enables the first electrode layer14to more reliably form an intermediate potential between two wiring lines adjacently disposed in the array direction (X-direction) of the wiring lines included in the wiring layer12. Since each of the wiring layer12, the first electrode layer14, and the second electrode layer22is a light-transmitting layer, it is possible to further enhance the visibility of the image to a user (e.g., the user H1) who views the image output from the display panel (e.g., the display panel60) from the front through the viewing angle control panel1.

The viewing angle control panel1also includes a drive circuit40capable of individually applying voltages to the wiring lines included in the wiring layer12. This configuration can facilitate voltage control for gradually increasing or decreasing the voltage applied to the wiring lines from one end to the other in the array direction of the wiring lines.

The display device100includes the display panel60and the viewing angle control panel1. The display panel displays an image. The viewing angle control panel1is stacked on the display surface of the display panel60. The display device100can more reliably inhibit an image from being visually recognized from an oblique viewpoint.

Modification

The specific aspect of the liquid crystal panel functioning as the viewing angle control panel according to the embodiment is not limited to the viewing angle control panel1described with reference toFIG.1. The following describes a modification of the liquid crystal panel functioning as the viewing angle control panel with reference toFIG.7. In the description of the modification, components similar to those according to the embodiment are denoted by the same reference numerals, and explanation thereof may be omitted.

FIG.7is a schematic sectional view of the main configuration of a viewing angle control panel1A. The viewing angle control panel1A includes a substrate10A instead of the substrate10of the viewing angle control panel1described with reference toFIG.1. The substrate includes the first substrate11, a wiring layer15, an insulating layer13A, and a first electrode layer14A.

The wiring layer15in the viewing angle control panel1A is provided instead of the wiring layer12in the viewing angle control panel1. The wiring layer15is formed on the first substrate11on the side facing the liquid crystal30. The wiring layer15may be made of light-transmitting conductive material or non-light-transmitting conductive material, what is called metal wiring, with a lower sheet resistance than the wiring layer12. While the light-transmitting conductive material used for the wiring layer15is copper, for example, it is not limited thereto and may be other conductive materials.

Similarly to the wiring layer12, the wiring layer15includes a plurality of wiring lines arrayed in the X-direction. InFIG.7, wiring lines151,152,153, and154arrayed from one side to the other in the X-direction are illustrated as the wiring lines. Similarly to the wiring lines121, . . . , and12mincluded in the wiring layer12in the viewing angle control panel1, the wiring lines included in the wiring layer15in the viewing angle control panel1A can be represented as wiring lines151, . . . , and15m. The wiring lines151,152,153, and154illustrated inFIG.7are an example of the wiring lines when m=4 is satisfied.

The wiring lines included in the wiring layer15are individually coupled to the drive circuit40similarly to the wiring lines121, . . . , and12mdescribed with reference toFIG.3. The drive circuit40individually applies voltages to the wiring lines included in the wiring layer15. The insulating layer13A is interposed between the wiring lines adjacently disposed in the X-direction out of the wiring lines included in the wiring layer15. Different wiring lines of the wiring lines included in the wiring layer15are insulated in the X-direction by the insulating layer13A and do not short-circuit.

The insulating layer13A is stacked on the wiring layer15on the side facing the liquid crystal30. The insulating layer13A has contact holes CH at the positions in contact with the respective wiring lines (e.g., the wiring lines151,152,153, and154) included in the wiring layer15in the Z-direction as illustrated inFIG.7. The contact hole CH is a hole passing through the insulating layer13A in the Z-direction. The first electrode layer14A enters into the contact holes CH. Except for the above noted items, the insulating layer13A is the same as the insulating layer13.

The first electrode layer14A is stacked on the insulating layer13A on the side facing the liquid crystal30. The first electrode layer14A entering into the contact holes CH is in contact with the wiring lines included in the wiring layer15. Except for the above noted items, the first electrode layer14A is the same as the first electrode layer14.

The following describes a case where the arrangement pitch composed of a space D3and a width D4in the X-direction of the wiring lines included in the wiring layer15in the viewing angle control panel1A is equal to the arrangement pitch composed of the space D1and the width D2in the X-direction of the wiring lines included in the wiring layer12in the viewing angle control panel1. The space D3in the X-direction where the insulating layer13A is interposed between the wiring lines adjacently disposed in the X-direction out of the wiring lines included in the wiring layer15is larger than the space D1. By contrast, the width D4in the X-direction of each of the wiring lines included in the wiring layer15is smaller than the width D2. This is because the contact holes CH allow the first electrode layer14A to be in contact with the wiring layer and the electric potential of the first electrode layer14A can be controlled so as to establish the relation of the regions V1, V2, and V3described with reference to FIG.2if the width D4is smaller than the width D2. Therefore, if the wiring layer15is made of a non-light-transmitting conductive material, the viewing angle control panel1A as a whole can exhibit such light transmittance property that causes substantially no problem in transmitting an image output from the display panel60described with reference toFIG.4. The modification can make the space D3larger than the width D4.

In the modification, the first electrode layer14A and the wiring layer15are provided such that the difference in sheet resistance between the first electrode layer14A and the wiring layer15is approximately 100:1. Except for the above noted items, the viewing angle control panel1A is the same as the viewing angle control panel1.

The viewing angle control panel1A is disposed between the backlight and the user (e.g., the users H1and H2) instead of the viewing angle control panel1described with reference toFIG.4. The modification can achieve the same advantageous effects as those according to the embodiment. In addition, the wiring lines included in the wiring layer can be made thinner because the wiring layer15is in contact with the first electrode layer14A through the contact holes CH formed in the insulating layer13A. Therefore, the wiring layer15can be made of non-light-transmitting material with higher conductivity and can further improve the power efficiency.

While the liquid crystal30according to the embodiment and the modification described above is a TN liquid crystal, the viewing angle control panels1and1A according to the present disclosure are not limited to TN liquid crystal panels. Any liquid crystal panel with a vertical electric field system can be employed as a light control panel, such as the viewing angle control panels1and1A.

The display panel60provided on the opposite side of the user (users H1and H2) who views an image across the viewing angle control panels1and1A is not limited to a liquid crystal panel. The display panel60may be a self-luminous display panel, such as an organic light-emitting diode (OLED) panel.

Out of other advantageous effects achieved by the aspects described in the present embodiment, advantageous effects clearly defined by the description in the present specification or appropriately conceivable by those skilled in the art are naturally achieved by the present disclosure.