Liquid crystal element

Abstract

To provide a liquid crystal element capable of easily adjusting the emitting direction of light.SOLUTION: The liquid crystal element 1 includes a plurality of electrode pairs C including a first electrode 11 and a second electrode 12 disposed on a first substrate 10 and a third electrode 21 and a fourth electrode 22 disposed on a second substrate 20, and a liquid crystal layer 30 between the first substrate 10 and the second substrate 20. The first electrodes 11, the second electrodes 12, the third electrodes 21, and the fourth electrodes 22 each extend along the first direction D1. In one of the pairs of electrodes C, the second electrodes 12 are disposed closer to the second substrate 20 than the first electrodes 11, and overlap the first ends D2 of the first electrodes 11 on the first end side in the second direction 11a in a plan view. The third electrodes 21 overlap the second ends D2 of the first electrodes 11 on the second end side in the second direction 11b in plan view. The fourth electrode 22 overlaps the second electrode 12 in plan view. The plurality of electrodes groups C are arranged along the second direction D2. The first electrode 11 is light-shielding.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a liquid crystal device. [Background technology]

[0002] Patent Document 1 discloses a headlight with controllable light distribution. The headlight in Patent Document 1 reflects light from a light source using a mirror, and then focuses the reflected light using a lens to irradiate it ahead of the vehicle. The direction of the light irradiation can be adjusted by adjusting the angle of the mirror.

[0003] Patent Document 2 discloses an illumination device including a lamp unit including a light source and an arm connected to the lamp unit. The arm includes a first arm and a second arm connected to be rotatable relative to each other. The lamp unit and the second arm are connected to be rotatable relative to each other. The angle between the first arm and the second arm and the angle between the lamp unit and the second arm are adjusted to adjust the direction in which light from the light source is emitted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-174551 [Patent Document 2] Japanese Patent Publication No. 2023-63255 Summary of the Invention [Problem to be solved by the invention]

[0005] In devices capable of adjusting the direction of light emission, such as those disclosed in Patent Documents 1 and 2, the adjustment of the direction of light emission is performed by operating a movable part in a mechanism including multiple mechanical parts. There is a demand for such devices with a simple configuration.

[0006] An object of the present disclosure is to provide a liquid crystal element that can easily adjust the light emission direction. [Means for solving the problem]

[0007] The liquid crystal element of the present disclosure comprises a first substrate and a second substrate facing each other, a plurality of electrode sets including a first electrode and a second electrode arranged on the first substrate and a third electrode and a fourth electrode arranged on the second substrate, and a liquid crystal layer between the first substrate and the second substrate, wherein the first electrode, the second electrode, the third electrode, and the fourth electrode each extend along a first direction, and in a second direction perpendicular to the first direction, the length of the first electrode is longer than the length of the second electrode, the length of the third electrode, and the length of the fourth electrode, and in one electrode set of the plurality of electrode sets, the second electrode is arranged closer to the second substrate than the first electrode and overlaps with a first end of the first electrode on a first end side in the second direction in a planar view, the third electrode overlaps with a second end of the first electrode on a second end side in the second direction in a planar view, and the fourth electrode overlaps with the second electrode in a planar view, the plurality of electrode sets are aligned along the second direction, and the first electrode has light-blocking properties. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a conceptual diagram of a liquid crystal element according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a plan view of a liquid crystal element according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is a cross-sectional view of the liquid crystal element taken along line III-III shown in FIG. [Figure 4] FIG. 4 is a plan view showing the arrangement of the first electrodes and the second electrodes. [Figure 5] FIG. 5 is a plan view showing the arrangement of the third electrode and the fourth electrode. [Figure 6] FIG. 6 is a diagram showing the phase difference of emitted light passing through the liquid crystal layer of the liquid crystal element shown in FIG. [Figure 7] FIG. 7 is a cross-sectional view of a liquid crystal element according to a modified example of the embodiment of the present disclosure. [Figure 8]FIG. 8 is a plan view showing the arrangement of the first electrode, the second electrode, and the fifth electrode shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each embodiment of the present disclosure will be described below with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially the same. Furthermore, the components described below can be combined as appropriate.

[0010] It should be noted that the disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive of while maintaining the gist of the present disclosure are naturally included within the scope of the present disclosure. Furthermore, in order to clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present disclosure. Furthermore, in this specification and each drawing, elements similar to those described above with respect to the previous drawings may be given the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0011] The first direction D1 and the second direction D2 shown in the drawings correspond to directions parallel to the plate surfaces of substrates included in the liquid crystal element 1, which will be described later. The first direction D1 and the second direction D2 correspond to the sides of the liquid crystal element 1. In the first direction D1, the side indicated by the arrow is the +D1 side, and the side opposite the +D1 side is the -D1 side. In the second direction D2, the side indicated by the arrow is the +D2 side, and the side opposite the +D2 side is the -D2 side.

[0012] The third direction D3 corresponds to the thickness direction of the liquid crystal element 1. In the third direction D3, the side indicated by the arrow is the +D3 side, and the side opposite to the +D3 side is the -D3 side. The +D3 side of the third direction D3 corresponds to the front side of the liquid crystal element 1, and the -D3 side of the third direction D3 corresponds to the rear side of the liquid crystal element 1. In this specification, "planar view" means viewing the liquid crystal element 1 along the third direction D3. Note that the first direction D1, the second direction D2, and the third direction D3 are merely examples, and the present disclosure is not limited to these directions.

[0013] 1 is a conceptual diagram of a liquid crystal element 1 according to an embodiment of the present disclosure. The liquid crystal element 1 is a refractive plate that refracts light. Light L emitted from a light source S is incident on the liquid crystal element 1. The light source S is, for example, a lighting device such as a vehicle headlight or spotlight.

[0014] When no voltage is applied, the liquid crystal element 1 transmits the emitted light L without changing the direction in which the emitted light L travels (emission direction), as indicated by the solid arrow. On the other hand, when a voltage is applied, the liquid crystal element 1 refracts the emitted light L so that it follows one of the two directions indicated by the dashed arrow (details will be described later).

[0015] Fig. 2 is a plan view of a liquid crystal element 1 according to an embodiment of the present disclosure. Fig. 3 is a cross-sectional view of the liquid crystal element 1 taken along line III-III shown in Fig. 2. The cross-sectional view of the liquid crystal element 1 shown in Fig. 3 shows the cross-sectional shape of the liquid crystal element 1 cut along a plane perpendicular to the first direction D1.

[0016] The liquid crystal element 1 includes a first substrate 10, a second substrate 20, and a liquid crystal layer 30.

[0017] The first substrate 10 and the second substrate 20 face each other. The first substrate 10 and the second substrate 20 are light-transmitting. The first substrate 10 and the second substrate 20 are, for example, glass substrates, resin substrates, or resin films.

[0018] On the first substrate 10, a plurality of first electrodes 11, a plurality of second electrodes 12, a first insulating layer IL1, and a first alignment film AL1 are arranged.

[0019] 4 is a plan view showing the arrangement of the first electrodes 11 and the second electrodes 12. The first electrodes 11 and the second electrodes 12 each extend along a first direction D1.

[0020] 3 and 4, the first electrode 11 and the second electrode 12 are aligned along the second direction D2. The length of the first electrode 11 is longer than the length of the second electrode 12 in the second direction D2.

[0021] The second electrodes 12 are arranged closer to the second substrate 20 than the first electrodes 11. One of the multiple second electrodes 12 overlaps, in plan view, a first end 11a of one of the multiple first electrodes 11 on the first end side (-D2 side) in the second direction D2. In other words, the first end 11a is a portion of the first electrode 11 that overlaps with the second electrode 12 in plan view. The first electrode 11 and the second electrode 12 overlap, in plan view, with a refraction region RA that refracts the emitted light L.

[0022] As shown in FIG. 4, the liquid crystal element 1 further includes a first stem electrode 13 and a second stem electrode 14 disposed on the first substrate 10.

[0023] The first trunk electrode 13 is located outside (on the -D1 side) of the refractive area RA in a plan view and extends along the second direction D2. The first trunk electrode 13 is electrically connected to the multiple first electrodes 11. The first trunk electrode 13 is integrated with the multiple first electrodes 11. The first trunk electrode 13 is electrically insulated from the second electrode 12.

[0024] The second stem electrode 14 is located outside (on the +D1 side of) the refractive area RA in a plan view and extends along the second direction D2. The second stem electrode 14 is electrically connected to the plurality of second electrodes 12. The second stem electrode 14 is integrated with the plurality of second electrodes 12. The second stem electrode 14 is electrically insulated from the first electrode 11.

[0025] The first stem electrode 13 and the second stem electrode 14 are electrically connected to a control circuit (not shown). The control circuit applies a voltage to the first electrode 11 via the first stem electrode 13. The control circuit applies a voltage to the second electrode 12 via the second stem electrode 14.

[0026] 3 electrically insulates the first trunk electrode 13 from the second trunk electrode 14. The first insulating layer IL1 also electrically insulates the first electrode 11 from the second electrode 12.

[0027] The first alignment film AL1 is disposed on the +D3 side of the first electrode 11 and the second electrode 12. The first alignment film AL1 is disposed in a state spaced apart from the first electrode 11 and the second electrode 12. The first alignment film AL1 may be in contact with the first electrode 11 and the second electrode 12.

[0028] On the second substrate 20, a plurality of third electrodes 21, a plurality of fourth electrodes 22, a second insulating layer IL2, and a second alignment film AL2 are arranged.

[0029] 5 is a plan view showing the arrangement of the third electrode 21 and the fourth electrode 22. The third electrode 21 and the fourth electrode 22 each extend along the first direction D1.

[0030] 3 and 5, the plurality of third electrodes 21 and the plurality of fourth electrodes 22 are arranged alternately along the second direction D2. The third electrodes 21 and the fourth electrodes 22 face each other in the second direction D2.

[0031] In the second direction D2, the length of the third electrode 21 and the length of the fourth electrode 22 are equal to the length of the second electrode 12. In other words, in the second direction D2, the length of the first electrode 11 is longer than the length of the second electrode 12, the length of the third electrode 21, and the length of the fourth electrode 22.

[0032] One of the plurality of third electrodes 21 overlaps in plan view with a second end portion 11b on the second end side (+D2 side) in the second direction D2 of one of the plurality of first electrodes 11. In other words, the second end portion 11b is a portion of the first electrode 11 that overlaps with the third electrode 21 in plan view.

[0033] Hereinafter, the portion of the first electrode 11 between the first end 11a and the second end 11b will be referred to as the intermediate portion 11c. The first end 11a, the second end 11b, and the intermediate portion 11c are integral. In the second direction D2, the length of the first end 11a and the length of the second end 11b are equal. In addition, in the second direction D2, the length of the intermediate portion 11c is equal to or longer than the length of the first end 11a. Note that the length of the intermediate portion 11c may be shorter than the length of the first end 11a.

[0034] Furthermore, one fourth electrode 22 of the multiple fourth electrodes 22 overlaps one second electrode 12 of the multiple second electrodes 12 in a planar view. That is, the one fourth electrode 22 overlaps a first end 11a of one first electrode 11 of the multiple first electrodes 11 in a planar view. The third electrode 21 and the fourth electrode 22 overlap a refraction region RA that refracts the emitted light L in a planar view.

[0035] As shown in FIG. 5, the liquid crystal element 1 further includes a third stem electrode 23 and a fourth stem electrode 24 disposed on the second substrate 20.

[0036] The third stem electrode 23 is located outside (on the -D1 side) of the refractive area RA in a plan view and extends along the second direction D2. The third stem electrode 23 is electrically connected to the plurality of third electrodes 21. The third stem electrode 23 is integrated with the plurality of third electrodes 21. The third stem electrode 23 is electrically insulated from the fourth electrode 22.

[0037] The fourth trunk electrode 24 is located outside the refractive area RA (on the +D1 side) in a plan view and extends along the second direction D2. The fourth trunk electrode 24 is electrically connected to the plurality of fourth electrodes 22. The fourth trunk electrode 24 is integrated with the plurality of fourth electrodes 22. The fourth trunk electrode 24 is electrically insulated from the third electrode 21.

[0038] The third stem electrode 23 and the fourth stem electrode 24 are electrically connected to a control circuit (not shown). The control circuit applies a voltage to the third electrode 21 via the third stem electrode 23. The control circuit applies a voltage to the fourth electrode 22 via the fourth stem electrode 24.

[0039] The first electrode 11, the second electrode 12, the first stem electrode 13, the second stem electrode 14, the third electrode 21, the fourth electrode 22, the third stem electrode 23, and the fourth stem electrode 24 are made of conductive materials such as molybdenum tungsten alloy (MoW) and TAT (Ti / Al / Ti), which is a laminate of titanium (Ti) and aluminum (Al). In this case, the second electrode 12, the first stem electrode 13, the second stem electrode 14, the third electrode 21, the fourth electrode 22, the third stem electrode 23, and the fourth stem electrode 24 have light-blocking properties.

[0040] The second electrode 12, the first stem electrode 13, the second stem electrode 14, the third electrode 21, the fourth electrode 22, the third stem electrode 23, and the fourth stem electrode 24 may be made of a light-transmitting conductive material such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGO (Indium Gallium Oxide), and IGZO (Indium Gallium Zinc Oxide). In this case, the second electrode 12, the first stem electrode 13, the second stem electrode 14, the third electrode 21, the fourth electrode 22, the third stem electrode 23, and the fourth stem electrode 24 do not have light-blocking properties.

[0041] That is, among the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22, at least the first electrode 11 has a light-blocking property.

[0042] As shown in Figure 3, the first length H1 along the second direction D2 between two adjacent first electrodes 11 in the second direction D2 is greater than or equal to the second length H2 along the second direction D2 of the portion of the first electrode 11 excluding the first end 11a (i.e., the portion including the second end 11b and the intermediate portion 11c).

[0043] Furthermore, one of the multiple first electrodes 11, and one second electrode 12, one third electrode 21, and one fourth electrode 22 that overlap that one first electrode in a planar view, constitute one electrode set C. In other words, the liquid crystal element 1 has multiple electrode sets C that include the first electrode 11 and the second electrode 12 arranged on the first substrate 10, and the third electrode 21 and the fourth electrode 22 arranged on the second substrate 20.

[0044] The plurality of electrode sets C are arranged along the second direction D2. The length between two adjacent electrode sets C in the second direction D2 corresponds to the first length H1.

[0045] As described above, the first electrode 11 has a light-blocking property. As a result, in the refractive region RA, the space between two electrode sets C adjacent to each other in the second direction D2 corresponds to an opening K through which light passes (see FIGS. 3 and 4). Furthermore, as described above, the first length H1 is equal to or greater than the second length H2. As a result, the opening K can be made larger, and the utilization efficiency of the emitted light L can be improved.

[0046] The second insulating layer IL2 electrically insulates the third stem electrode 23 from the fourth stem electrode 24. The second insulating layer IL2 also electrically insulates the third electrode 21 from the fourth electrode 22.

[0047] The second alignment film AL2 is disposed on the −D3 side of the third electrode 21 and the fourth electrode 22. The second alignment film AL2 is disposed in a state spaced apart from the third electrode 21 and the fourth electrode 22. The second alignment film AL2 may be in contact with the third electrode 21 and the fourth electrode 22.

[0048] The liquid crystal layer 30 is located between the first substrate 10 and the second substrate 20. The liquid crystal layer 30 is sandwiched between a first alignment film AL1 and a second alignment film AL2. The first alignment film AL1 and the second alignment film AL2 determine the alignment (initial alignment) of the liquid crystal molecules LM contained in the liquid crystal layer 30 when no voltage is applied to the liquid crystal element 1. The initial alignment of the liquid crystal molecules LM is a direction in which the long axis Ax of the liquid crystal molecules LM is perpendicular to the third direction D3 (horizontal alignment). The alignment direction of the first alignment film AL1 and the alignment direction of the second alignment film AL2 are parallel to each other in a planar view.

[0049] The liquid crystal element 1 is an ECB (Electrically Controlled Birefringence) liquid crystal element, although it goes without saying that the liquid crystal element 1 is not limited to an ECB liquid crystal element.

[0050] Next, we will explain the operation of the liquid crystal element 1 when it refracts the light L emitted from the light source S. When a control circuit applies voltages to the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22, the liquid crystal element 1 refracts the light L. The light L enters the liquid crystal element 1 from the rear surface of the first substrate 10 along the third direction D3. Note that the symbol in parentheses attached to the light L in the drawings indicates the direction in which the light L travels. Also, in FIG. 3, the light L emitted from the liquid crystal element 1 is shown on the +D3 side of the liquid crystal element 1.

[0051] When no voltage is applied to the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22, the alignment state of all the liquid crystal molecules LM contained in the liquid crystal layer 30 is the initial alignment (horizontal alignment), and the tilt degrees of all the liquid crystal molecules LM are equal to one another. Therefore, the amount of phase change of the output light L passing through the liquid crystal layer 30 is equal at all parts of the liquid crystal layer 30, and no phase difference occurs in the output light L. Therefore, the liquid crystal element 1 outputs the output light L without refracting it. Specifically, as shown in FIG. 3, the liquid crystal element 1 outputs the output light L incident along the third direction D3 without refracting it.

[0052] When the liquid crystal element 1 refracts light L emitted from the light source S, voltages are applied to the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22 so that the magnitude of a first potential difference (ED1) between the potential (E1) of the first electrode 11 and the potential (E3) of the third electrode 21 is different from the magnitude of a second potential difference (ED2) between the potential (E2) of the second electrode 12 and the potential (E4) of the fourth electrode 22. Hereinafter, when the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22 are described without distinction, they will be simply referred to as "electrodes." In the drawings, the symbols in parentheses attached to the emitted light L indicate the direction in which the emitted light L travels.

[0053] Specifically, when the liquid crystal element 1 refracts the emitted light L so that it travels along a fourth direction D4 that is inclined toward the -D2 side with respect to the third direction D3, a voltage is applied to the electrodes so that the magnitude of the second potential difference is larger than the magnitude of the first potential difference (ED1 <ED2)。

[0054] When a voltage is applied to the electrodes, an electric field acts on the liquid crystal layer 30, causing the liquid crystal molecules LM to tilt. The greater the magnitude of the potential difference in the liquid crystal layer 30 in the third direction D3, the greater the degree of tilt of the liquid crystal molecules LM (the greater the angle between the long axis Ax of the liquid crystal molecule LM and the second direction D2).

[0055] Furthermore, the greater the tilt degree of the liquid crystal molecules LM, the more advanced the phase of the emitted light L passing through the liquid crystal layer 30. That is, the greater the magnitude of the potential difference in the liquid crystal layer 30 in the third direction D3, the more advanced the phase of the emitted light L becomes.

[0056] When the liquid crystal element 1 refracts the emitted light L so that it travels along the fourth direction D4, the magnitude of the second potential difference (ED2) is greater than the magnitude of the first potential difference (ED1), as described above. Therefore, the degree of tilt of the liquid crystal molecules LM between the second electrode 12 and the fourth electrode 22 is greater than the degree of tilt of the liquid crystal molecules LM between the first electrode 11 and the third electrode 21. Furthermore, the magnitude of the potential difference and the degree of tilt of the liquid crystal molecules LM in the third direction D3 increase as the distance from the -D2 side to the +D2 side in the second direction D2 increases in the opening K.

[0057] In addition, voltages are applied to the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22 such that the potential of the first electrode 11 is different from the potential of the second electrode 12, and the potential of the third electrode 21 is different from the potential of the fourth electrode 22. That is, a potential difference occurs between the potential of the first electrode 11 and the potential of the second electrode 12. Also, a potential difference occurs between the potential of the third electrode 21 and the potential of the fourth electrode 22.

[0058] When the liquid crystal element 1 refracts the emitted light L so as to travel along the fourth direction D4, for example, the voltage is applied to the electrodes such that the potential (E2) of the second electrode 12 is greater than the potential (E1) of the first electrode 11 (E1 < E2), and the potential (E3) of the third electrode 21 is greater than the potential (E4) of the fourth electrode 22 (E4 < E3).

[0059] In this case, for example, the potential (E3) of the third electrode 21 is greater than the potential (E1) of the first electrode 11 (E1 < E3), the potential (E1) of the first electrode 11 is greater than the potential (E4) of the fourth electrode 22 (E4 < E1), and the potential (E2) of the second electrode 12 is equal to the potential (E3) of the third electrode 21 (E2 = E3). That is, in this case, the relationship between the potentials of the electrodes is represented by the following formula (1).

[0060] E4 < E1 < E2 = E3 ···(1)

[0061] Furthermore, in this case, as represented by formula (2), the potential (E2) of the second electrode 12 and the potential (E4) of the fourth electrode 22 are the same in magnitude and different in polarity from each other.

[0062] E2 = (-1) × E4 ···(2)

[0063] When the relationship between the potentials of the electrodes satisfies the relationships of formulas (1) and (2), it becomes possible to control the potentials of the electrodes by a column inversion driving method in which the polarities of the potentials of the electrodes are periodically inverted. Needless to say, the relationship between the potentials of the electrodes is not limited to the relationships of formulas (1) and (2).

[0064] FIG. 6 is a diagram showing the phase difference of the emitted light L passing through the liquid crystal layer 30 of the liquid crystal element 1 shown in FIG. 3. In FIG. 6, the relationship between the potentials of the electrodes is the relationship shown in Expressions (1) and (2), and the case where a voltage is applied to the electrodes is shown such that the magnitude (ED2) of the second potential difference is approximately twice the magnitude (ED1) of the first potential difference.

[0065] The vertical axis of FIG. 6 indicates the phase difference of the emitted light L. The horizontal axis of FIG. 6 indicates the position in the second direction D2 of the liquid crystal layer 30. In FIG. 6, the range of “(11a)” indicates the range of the first end portion 11a of the first electrode 11 in the second direction D2, and the range of “(11b)” indicates the range of the second end portion 11b of the first electrode 11 and the second electrode 12 in the second direction D2. That is, between “(11a)” and “(11b)” in FIG. 6 corresponds to the range of the aperture K. In FIG. 6, the phase difference of the emitted light L passing through the liquid crystal layer 30 with the phase of the emitted light L passing through the end on the -D2 side in the aperture K as a reference (zero) is shown by a solid line.

[0066] Since the magnitude of the second potential difference is larger than the magnitude of the first potential difference (ED1 < ED2), the phase difference increases as it goes from the -D2 side to the +D2 side along the second direction D2 in the aperture K. That is, the phase of the emitted light L passing through the liquid crystal layer 30 advances as it goes from the -D2 side to the +D2 side along the second direction D2 in the aperture K. Thereby, the emitted light L is refracted so as to be emitted along the fourth direction D4.

[0067] On the other hand, when the emitted light L is refracted so as to travel along the fifth direction D5 in which the liquid crystal element 1 is inclined toward the +D2 side with respect to the third direction D3, a voltage is applied to the electrodes such that the magnitude (ED1) of the first potential difference is larger than the magnitude (ED2) of the second potential difference (ED2 < ED1). Also, in this case, voltages are applied to the first electrode 11, the second electrode 12, the third electrode 21, and the fourth electrode 22 such that the potential of the first electrode 11 and the potential of the second electrode 12 are different from each other, and the potential of the third electrode 21 and the potential of the fourth electrode 22 are different from each other. In this case, the relationship between the potentials of the electrodes may be the relationship expressed by the following Expressions (3) and (4).

[0068] E3 < E2 < E1 = E4 ···(3)

[0069] E1 = (-1) × E3 ···(4)

[0070] When the relationship between the electrode potentials satisfies the relationships of formulas (3) and (4), it becomes possible to control the electrode potential by a column inversion driving method in which the polarity of the electrode potential periodically reverses. Needless to say, the relationship between the electrode potentials is not limited to the relationships of formulas (3) and (4).

[0071] Since the magnitude of the first potential difference is larger than the magnitude of the second potential difference (ED2 < ED1), the phase difference along the third direction D3 increases as it goes from the +D2 side to the -D2 side along the second direction D2 at the opening K. That is, the phase of the emitted light L passing through the liquid crystal layer 30 advances as it goes from the +D2 side to the -D2 side along the second direction D2 at the opening K. Thereby, the emitted light L refracts so as to be emitted along the fifth direction D5.

[0072] Thus, by controlling the voltage applied to the electrodes, the liquid crystal element 1 can easily adjust the emission direction of the emitted light L.

[0073] As described above, the preferred embodiments of the present disclosure have been described, but the present disclosure is not limited to such embodiments. The content disclosed in the embodiments is merely an example, and various changes are possible without departing from the gist of the present disclosure. Appropriate changes made without departing from the gist of the present disclosure also naturally belong to the technical scope of the present disclosure.

[0074] For example, a voltage may be applied to the electrodes such that the potential of the third electrode 21 is equal to the potential of the fourth electrode 22.

[0075] 7 is a cross-sectional view of a liquid crystal element 1 according to a modified example of the embodiment of the present disclosure. The liquid crystal element 1 of this modified example will be described mainly with respect to differences from the liquid crystal element 1 of the above-described embodiment. In this modified example, the liquid crystal element 1 further includes a plurality of fifth electrodes 115 arranged on the first substrate 10. Each of the plurality of electrode sets C includes one fifth electrode 115.

[0076] Fig. 8 is a plan view showing the arrangement of the first electrode 11, the second electrode 12, and the fifth electrode 115 shown in Fig. 7. The fifth electrode 115 extends along the first direction D1.

[0077] 7 and 8, the second electrodes 12 and the fifth electrodes 115 are arranged alternately along the second direction D2. The second electrodes 12 and the fifth electrodes 115 face each other in the second direction D2.

[0078] In the second direction D2, the length of the fifth electrode 115 is equal to the length of the second electrode 12. That is, the length of the first electrode 11 is longer than the length of the fifth electrode 115 in the second direction D2.

[0079] The fifth electrode 115 is disposed closer to the second substrate 20 than the first electrode 11. In one electrode set C among the plurality of electrode sets C, the fifth electrode 115 overlaps with the third electrode 21 in a planar view. That is, the fifth electrode 115 overlaps with the second end 11b of the first electrode 11 in a planar view. The fifth electrode 115 overlaps with the refraction region RA that refracts the emitted light L in a planar view.

[0080] As shown in FIG. 8, the liquid crystal element 1 further includes a fifth stem electrode 116 disposed on the first substrate 10. The fifth stem electrode 116 is located outside (on the -D1 side of) the refractive area RA in a plan view and extends along the second direction D2. The fifth stem electrode 116 is electrically connected to the plurality of fifth electrodes 115. The fifth stem electrode 116 is integrated with the plurality of fifth electrodes 115. The fifth stem electrode 116 is electrically insulated from the first electrode 11 and the second electrode 12.

[0081] The fifth main electrode 116 is electrically connected to a control circuit. The control circuit applies a voltage to the fifth electrode 115 via the fifth main electrode 116. The first insulating layer IL1 electrically insulates between the first main electrode 13 and the second main electrode 14 and the fifth main electrode 116. Also, the first insulating layer IL1 electrically insulates between the first electrode 11 and the second electrode 12 and the fifth electrode 115. The materials of the fifth electrode 115 and the fifth main electrode 116 are the same as the material of the second electrode 12.

[0082] As shown in FIG. 7, the first length H1 is not less than a third length H3 along a second direction D2 of a portion of the first electrode 11 excluding the first end portion 11a and the second end portion 11b (that is, the intermediate portion 11c). Thereby, the aperture K can be enlarged, and the utilization efficiency of the emitted light L can be improved.

[0083] Next, the operation when the liquid crystal element 1 of this modified example refracts the emitted light L of the light source S will be described.

[0084] When the liquid crystal element 1 refracts the emitted light L of the light source S, voltages are applied to the second electrode 12, the third electrode 21, the fourth electrode 22, and the fifth electrode 115 so that the magnitude (ED2) of the second potential difference between the potential (E2) of the second electrode 12 and the potential (E4) of the fourth electrode 22 and the magnitude (ED3) of the third potential difference between the potential (E3) of the third electrode 21 and the potential (E5) of the fifth electrode 115 are different. Hereinafter, when the first electrode 11, the second electrode 12, the third electrode 21, the fourth electrode 22, and the fifth electrode 115 are described without distinction, they are simply referred to as electrodes.

[0085] When voltages are applied to the electrodes so that the magnitude of the second potential difference is greater than the magnitude of the third potential difference (ED3 < ED2), the phase of the emitted light L passing through the liquid crystal layer 30 advances from the -D2 side toward the +D2 side along the second direction D2 in the aperture K. Thereby, the emitted light L refracts so as to be emitted along the fourth direction D4.

[0086] In this case, voltages may be applied to the second electrode 12, the third electrode 21, the fourth electrode 22, and the fifth electrode 115 such that the potential of the second electrode 12 is different from the potential of the fifth electrode 115, and the potential of the third electrode 21 is different from the potential of the fourth electrode 22. In this case, the relationship between the potentials of the electrodes may be the relationship represented by the following formulas (5) and (6).

[0087] E4 < E5 < E2 = E3 ···(5)

[0088] E2 = (-1)×E4 ···(6)

[0089] When the relationship between the potentials of the electrodes satisfies the relationships of formulas (5) and (6), it becomes possible to control the potentials of the electrodes by a column inversion driving method in which the polarities of the potentials of the electrodes are periodically inverted.

[0090] On the other hand, when voltages are applied to the electrodes such that the magnitude of the third potential difference is greater than the magnitude of the second potential difference (ED2 < ED3), the phase of the emitted light L passing through the liquid crystal layer 30 advances more from the +D2 side to the -D2 side along the second direction D2 at the opening K. As a result, the emitted light L is refracted so as to be emitted along the fifth direction D5.

[0091] In this case, the relationship between the potentials of the electrodes may be the relationship represented by the following formulas (7) and (8).

[0092] E3 < E2 < E5 = E4 ···(7)

[0093] E5 = (-1)×E3 ···(8)

[0094] When the relationship between the potentials of the electrodes satisfies the relationships of formulas (7) and (8), it becomes possible to control the potentials of the electrodes by a column inversion driving method in which the polarities of the potentials of the electrodes are periodically inverted.

[0095] When a voltage is applied to the electrodes such that the magnitude of the second potential difference is greater than the magnitude of the third potential difference (ED3 < ED2), and in both cases where a voltage is applied to the electrodes such that the magnitude of the third potential difference is greater than the magnitude of the second potential difference (ED2 < ED3), the potential (E1) of the first electrode 11 is equal to the potential (E5) of the fifth electrode 115. Note that in both of these cases, the potential (E1) of the first electrode 11 may also be a potential between the potential (E2) of the second electrode 12 and the potential (E5) of the fifth electrode 115. The potential of the first electrode 11 can adjust the phase difference along the second direction D2 at the opening K.

[0096] Also, with regard to other operational effects brought about by the aspects described in the above embodiments that are clear from the description herein or can be appropriately conceived by those skilled in the art, they are naturally understood to be brought about by the present disclosure.

Explanation of Reference Numerals

[0097] 1 Liquid crystal element 10 First substrate 11 First electrode 11a First end 11b Second end 12 Second electrode 20 Second substrate 21 Third electrode 22 Fourth electrode 30 Liquid crystal layer 115 Fifth electrode C Electrode group D1 First direction D2 Second direction

Claims

1. a first substrate and a second substrate facing each other; a plurality of electrode sets including a first electrode and a second electrode disposed on the first substrate, and a third electrode and a fourth electrode disposed on the second substrate; a liquid crystal layer between the first substrate and the second substrate; the first electrode, the second electrode, the third electrode, and the fourth electrode each extend along a first direction; In a second direction perpendicular to the first direction, a length of the first electrode is longer than a length of the second electrode, a length of the third electrode, and a length of the fourth electrode; In one electrode set among the plurality of electrode sets, the second electrode is disposed closer to the second substrate than the first electrode and overlaps, in a plan view, a first end of the first electrode on a first end side in the second direction; the third electrode overlaps, in a plan view, a second end portion of the first electrode on a second end side in the second direction, the fourth electrode overlaps with the second electrode in a plan view, the plurality of electrode sets are aligned along the second direction, the first electrode has a light-shielding property; Liquid crystal element.

2. a first length along the second direction between two of the first electrodes adjacent to each other in the second direction is equal to or greater than a second length along the second direction of a portion of the first electrode excluding the first end portion; The liquid crystal device according to claim 1 .

3. Voltages are applied to the first electrode, the second electrode, the third electrode, and the fourth electrode such that a first potential difference between a potential of the first electrode and a potential of the third electrode and a second potential difference between a potential of the second electrode and a potential of the fourth electrode are different from each other. The liquid crystal device according to claim 1 .

4. voltages are applied to the first electrode, the second electrode, the third electrode, and the fourth electrode such that a potential of the first electrode and a potential of the second electrode are different from each other and a potential of the third electrode and a potential of the fourth electrode are different from each other; The liquid crystal device according to claim 1 .

5. Each of the plurality of electrode sets further includes a fifth electrode disposed on the first substrate and extending along the first direction; In one electrode set among the plurality of electrode sets, the fifth electrode is disposed closer to the second substrate than the first electrode and overlaps with the third electrode in a plan view. The liquid crystal device according to claim 1 .

6. a first length along the second direction between two of the first electrodes adjacent to each other in the second direction is equal to or greater than a third length along the second direction of a portion of the first electrode excluding the first end and the second end; The liquid crystal device according to claim 5 .

7. Voltages are applied to the second electrode, the third electrode, the fourth electrode, and the fifth electrode such that a second potential difference between a potential of the second electrode and a potential of the fourth electrode and a third potential difference between a potential of the third electrode and a potential of the fifth electrode are different from each other. The liquid crystal device according to claim 5 .

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