Liquid crystal optical element and lighting device

Abstract

A liquid crystal optical element (10) according to the present invention comprises a first liquid crystal cell (110a) and a second liquid crystal cell (110b) that overlaps with the first liquid crystal cell (110a). The first liquid crystal cell (110a) and the second liquid crystal cell (110b) each comprise: a first substrate (111a, 111b); first electrodes (181) and second electrodes (182) disposed on the first substrate (111a, 111b); a second substrate (121a, 121b) disposed facing the first substrate (111a, 111b); third electrodes (183) and fourth electrodes (184) disposed on the second substrate (121a, 121b); and a liquid crystal layer (160a, 160b) disposed between the first substrate (111a, 111b) and the second substrate (121a, 121b). The first electrodes (181) and the second electrodes (182) are alternatingly disposed parallel to a first direction (x axis); the third electrodes (183) and the fourth electrodes (184) are alternatingly disposed parallel to the first direction (x axis); each of the first electrodes (181) overlaps with a first end of a third electrode (183), a space between said third electrode (183) and a fourth electrode (184), and a first end of said fourth electrode (184); and each of the fourth electrodes (184) overlaps with a space between a first electrode (181) and a second electrode (182) and a first end of said second electrode (182).

Description

Liquid crystal optical element and lighting device

[0001] An embodiment of the present invention relates to an element that controls light distribution by utilizing the optical characteristics of liquid crystal, and a lighting device including an element that controls light distribution by utilizing the optical characteristics of liquid crystal.

[0002] A liquid crystal lens is known as an optical element (liquid crystal optical element) that uses liquid crystal and electrically controls the focal length by supplying a voltage to the liquid crystal to change the refractive index of the liquid crystal. For example, Patent Document 1 describes an illumination device that can control the spread of light using a liquid crystal lens.

[0003] JP 2010-231976 A

[0004] For example, in recent years, there has been a demand for lighting devices that are capable of controlling the direction in which light is distributed (orientation direction) and the angle at which light is distributed (orientation angle).

[0005] In view of the above-mentioned problems, an object of one embodiment of the present invention is to provide a liquid crystal optical element and a lighting device that are capable of controlling the light distribution direction and light distribution angle.

[0006] A liquid crystal optical element according to one embodiment of the present invention includes a first liquid crystal cell and a second liquid crystal cell overlapping the first liquid crystal cell, each of the first liquid crystal cell and the second liquid crystal cell including a first substrate, a first electrode and a second electrode disposed on the first substrate, a second substrate disposed opposite to the first substrate, a third electrode and a fourth electrode disposed on the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, and the first electrode and the second electrode are alternately disposed parallel to a first direction. and extends in a second direction intersecting the first direction, the third electrodes and fourth electrodes are alternately arranged parallel to the first direction and extend in the second direction, the first electrodes overlap with a first end of the third electrode, a space between the third electrode and the fourth electrode, and a first end of the fourth electrode in a third direction intersecting the first direction and the second direction, and the fourth electrode overlaps with a space between the first electrode and the second electrode and a first end of the second electrode in the third direction.

[0007] An illumination device according to an embodiment of the present invention includes a first liquid crystal cell and a second liquid crystal cell overlapping the first liquid crystal cell, each of the first liquid crystal cell and the second liquid crystal cell including a first substrate, a first electrode and a second electrode disposed on the first substrate, a second substrate disposed opposite to the first substrate, a third electrode and a fourth electrode disposed on the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, the first electrode and the second electrode being alternately disposed parallel to a first direction and extending in a second direction intersecting the first direction, and the third electrode and the fourth electrode the liquid crystal optical element is arranged alternately in parallel to the first direction and extends in the second direction, the first electrodes overlapping with a first end of the third electrode, a space between the third electrode and the fourth electrode, and a first end of the fourth electrode in a third direction intersecting the first direction and the second direction, and the fourth electrode overlapping with a space between the first electrode and the second electrode and a first end of the second electrode in the third direction; and a control device electrically connected to the liquid crystal optical element and supplying control signals to the first electrodes, the second electrodes, the third electrodes, and the fourth electrodes.

[0008] A liquid crystal optical element according to one embodiment of the present invention includes a first liquid crystal cell and a second liquid crystal cell overlapping the first liquid crystal cell, each of the first liquid crystal cell and the second liquid crystal cell including a first substrate, a first electrode and a second electrode disposed on the first substrate, a second substrate disposed opposite to the first substrate, a third electrode and a fourth electrode disposed on the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, the first electrode and the second electrode being alternately disposed parallel to a first direction and extending in a second direction intersecting the first direction, The third electrode is arranged parallel to the first direction and extends in the second direction, the fourth electrode is arranged on the second substrate so as to cover the third electrode, the first electrode overlaps with a first end of the third electrode and a space between the third electrodes in a third direction intersecting the first direction and the second direction, the third electrode overlaps with the space between the first electrode and the second electrode and a first end of the second electrode in the third direction, and the space between the third electrodes overlaps with the space between the first electrode and a second electrode different from the second electrode.

[0009] 1 is a perspective view showing the configuration of an illumination device according to a first embodiment of the present invention; FIG. 2 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a first embodiment of the present invention; FIG. 3 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a first embodiment of the present invention; FIG. 4 is a plan view showing the arrangement of electrodes of a liquid crystal optical element according to a first embodiment of the present invention; FIG. 5 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a first embodiment of the present invention; FIG. 6 is a cross-sectional view for explaining the light distribution using a liquid crystal optical element according to a first embodiment of the present invention; FIG. 7 is a cross-sectional view showing the orientation of liquid crystals in a liquid crystal layer in a liquid crystal optical element according to a first embodiment of the present invention; FIG. 8 is a cross-sectional view showing the relationship between each region and a phase difference in a liquid crystal optical element according to a first embodiment of the present invention; FIG. 9 is a cross-sectional view showing the orientation of liquid crystals in a liquid crystal layer in a liquid crystal optical element according to a first embodiment of the present invention; FIG. 10 is a timing chart showing voltages supplied to each terminal included in a liquid crystal optical element according to a first embodiment of the present invention; FIG. 11 is a schematic view for explaining the direction of light distribution in an illumination device according to a first embodiment of the present invention; FIG. 12 is a schematic view showing a light source according to a first embodiment of the present invention; FIG. 13 is a schematic view showing a light source according to a first embodiment of the present invention; FIG. 14 is a perspective view showing the configuration of an illumination device according to a second embodiment of the present invention; FIG. 15 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a second embodiment of the present invention. FIG. 1 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a second embodiment of the present invention. FIG. 2 is a plan view showing the arrangement of electrodes of a liquid crystal optical element according to a second embodiment of the present invention. FIG. 3 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view for explaining the light distribution using a liquid crystal optical element according to a second embodiment of the present invention. FIG. 5 is a diagram showing the relationship between each region and a phase difference in a liquid crystal optical element according to a second embodiment of the present invention. FIG. 6 is a timing chart showing voltages supplied to each terminal included in a liquid crystal optical element according to a second embodiment of the present invention. FIG. 7 is a perspective view showing the configuration of a lighting device according to a third embodiment of the present invention.1 is a plan view showing the arrangement of electrodes of a liquid crystal optical element according to a third embodiment of the present invention; FIG. 2 is a perspective view showing the configuration of an illumination device according to a fourth embodiment of the present invention; and FIG. 3 is a cross-sectional view showing the cross-sectional structure of a part of a liquid crystal optical element according to a fourth embodiment of the present invention.

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention can be implemented in many different forms, and should not be construed as being limited to the description of the following exemplary embodiments. For clarity of explanation, the drawings may show schematic representations of the width, thickness, shape, etc. of each part compared to the actual form. However, 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 designated by the same reference numeral or number followed by an alphabet such as a, b, A, or B, or by a number followed by a hyphen and a number, and detailed description may be omitted as appropriate. Furthermore, the letters "first" and "second" attached to each element are convenient labels used to distinguish each element and have no further meaning unless otherwise specified.

[0011] In this specification, when a component or region is referred to as being "on (or under)" another component or region, unless otherwise specified, this includes not only the case where it is directly above (or directly under) the other component or region, but also the case where it is above (or under) the other component or region, i.e., the case where another component is included between the component or region and above (or under) the other component or region.

[0012] In addition, in this specification, when a single film is processed to form multiple structures, each structure may have a different function or role, and each structure may be formed on a different base. However, these multiple structures are derived from a film formed as the same layer in the same process and have the same material. Therefore, these multiple films are defined as existing in the same layer.

[0013] Furthermore, in this specification, unless otherwise specified, expressions such as "α includes A, B, or C," "α includes any one of A, B, and C," and "α includes one selected from the group consisting of A, B, and C" do not exclude cases where α includes multiple combinations of A to C. Furthermore, these expressions do not exclude cases where α includes other elements.

[0014] In this specification, the x-axis direction, the y-axis direction intersecting the x-axis direction, and the z-axis direction intersecting the x-axis and y-axis may be referred to as the first direction, the second direction, and the third direction, respectively. The x-axis is perpendicular to the y-axis, and the z-axis is perpendicular to the xy plane (the x-axis and y-axis).

[0015] In this specification, when the terms orthogonal, perpendicular, parallel, identical, and coincident are used, the orthogonal, perpendicular, identical, and coincident may include a tolerance within the design range.

[0016] <First embodiment> <1-1. Configuration of lighting device 100> An outline of the configuration of a lighting device 100 according to the first embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic perspective view showing the configuration of the lighting device 100.

[0017] 1, the lighting device 100 includes a liquid crystal optical element 10, a light source 30, and a control device 40. As will be described in detail later, the liquid crystal optical element 10 includes a first liquid crystal cell 110a, an adhesive layer 130a, a wave plate 140, an adhesive layer 130b, and a second liquid crystal cell 110b. The adhesive layer 130a is provided between the first liquid crystal cell 110a and the wave plate 140, and the adhesive layer 130b is provided between the wave plate 140 and the second liquid crystal cell 110b. The first liquid crystal cell 110a, the adhesive layer 130a, the wave plate 140, the adhesive layer 130b, and the second liquid crystal cell 110b are stacked in this order along the z-axis direction, from the side closest to the light source.

[0018] The first liquid crystal cell 110a and the second liquid crystal cell 110b have the same basic configuration and function. Therefore, when the first liquid crystal cell 110a and the second liquid crystal cell 110b are not distinguished, the liquid crystal cell will be described as the liquid crystal cell 110, and when the first liquid crystal cell 110a and the second liquid crystal cell 110b are distinguished, the liquid crystal cell will be described as the first liquid crystal cell 110a and the second liquid crystal cell 110b.

[0019] The adhesive layer 130a bonds and fixes the first liquid crystal cell 110a and the wave plate 140. The adhesive layer 130b bonds and fixes the wave plate 140 and the second liquid crystal cell 110b. The adhesive layers 130a and 130b can be formed from an optically elastic resin. The optically elastic resin is, for example, an adhesive material containing a light-transmitting acrylic resin.

[0020] The wave plate 140 has a function of controlling polarization. For example, the wave plate 140 has a function of providing a phase difference between the polarized component in the x-axis direction (P-polarized component) and the polarized component in the y-axis direction (S-polarized component) contained in the light emitted from the light source (incident light 180) and outputting the light. For example, the phase difference may be λ / 2 or may be other than λ / 2. As an example, the wave plate 140 of the lighting device 100 is a wave plate with a phase difference of λ / 2.

[0021] The light source 30 emits light toward the liquid crystal optical element 10. For example, the light source 30 may include a light-emitting diode (LED). The light source 30 used in the lighting device 100 is not limited to an LED. The light source 30 may be any element or device that can emit light. Furthermore, the light source 30 may include a plurality of LEDs.

[0022] The control device 40 controls the liquid crystal optical element 10 and the light source 30. Specifically, the control device 40 supplies, to the first liquid crystal cell 110a and the second liquid crystal cell 110b of the liquid crystal optical element 10, control signals (electric potentials) capable of controlling the light distribution direction and orientation angle of light, and can supply control signals (electric potentials) capable of controlling the lighting and brightness of the light source 30.

[0023] The liquid crystal optical element 10 and the light source 30 are electrically connected to the control device 40. For example, the control device 40 is electrically connected to the liquid crystal optical element 10 and the second liquid crystal cell 110b. The control device 40 is electrically connected via a first flexible wiring board 11a electrically connected to the terminal portion 12a of the first liquid crystal cell 110a and a second flexible wiring board 11b electrically connected to the terminal portion 12b of the second liquid crystal cell 110b.

[0024] Light emitted from the light source 30 to the liquid crystal optical element 10 passes through the first liquid crystal cell 110a, the adhesive layer 130a, the wave plate 140, the adhesive layer 130b, and the second liquid crystal cell 110b, and is emitted from the second liquid crystal cell 110b. Although details will be described later, for example, light passing through the liquid crystal optical element 10 is refracted in the x-axis direction or the y-axis direction based on the configuration of each electrode included in the liquid crystal cell 110 and the voltage supplied to each electrode from the control device 40. In other words, the lighting device 100 can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 10, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0025] <1-2. Structure of the Liquid Crystal Optical Element 10> The structure of the liquid crystal optical element 10 will be outlined with reference to Figs. 2 and 3. Figs. 2 and 3 are schematic cross-sectional views showing the cross-sectional structure of a portion of the liquid crystal optical element 10. Specifically, Fig. 2 is a schematic cross-sectional view in the zx plane taken along line A1-A2 shown in Fig. 1, and Fig. 3 is a schematic cross-sectional view in the yz plane taken along line B1-B2 shown in Fig. 1. Furthermore, structures that are the same as or similar to those in Fig. 1 will be described as necessary.

[0026] As explained in "1-1. Configuration of lighting device 100," the first liquid crystal cell 110a and the second liquid crystal cell 110b have the same basic configuration and function. In the following explanation, the configuration and function of the first liquid crystal cell 110a will be explained, and the configuration and function of the second liquid crystal cell 110b will be explained as necessary.

[0027] The first liquid crystal cell 110a includes a first substrate 111a, a second substrate 121a, a plurality of first transparent electrodes 181 (e.g., first transparent electrode 181-1a), a plurality of second transparent electrodes 182 (e.g., second transparent electrode 182-1a, second transparent electrode 182-2a), a plurality of third transparent electrodes 183 (e.g., third transparent electrode 183-1a, third transparent electrode 183-2a), a plurality of fourth transparent electrodes 184 (e.g., fourth transparent electrode 184-1a, fourth transparent electrode 184-2a), a first alignment film 114a, a second alignment film 124a, and a liquid crystal layer 160a.

[0028] The plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 are provided on the first substrate 111a and are covered with a first alignment film 114a. A portion of the first alignment film 114a is in contact with the first substrate 111a, the plurality of first transparent electrodes 181, and the plurality of second transparent electrodes 182.

[0029] The plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184 are provided on the second substrate 121a and are covered with a second alignment film 124a. Parts of the second alignment film 124a are in contact with the second substrate 121a, the plurality of third transparent electrodes 183, and the plurality of fourth transparent electrodes 184.

[0030] The first transparent electrode 181 and the second transparent electrode 182 on the first substrate 111a are disposed so as to face the third transparent electrode 183 and the fourth transparent electrode 184 on the second substrate 121a.

[0031] Note that a sealant (not shown) is provided around the peripheries of the first substrate 111a and the second substrate 121a to bond the first substrate 111a and the second substrate 121a together. A liquid crystal layer 160a containing liquid crystal is provided in a space surrounded by the first substrate 111a (more specifically, the first alignment film 114a), the second substrate 121a (more specifically, the second alignment film 124a), and the sealant.

[0032] The plurality of first transparent electrodes 181, the plurality of second transparent electrodes 182, the plurality of third transparent electrodes 183, and the plurality of fourth transparent electrodes 184 each extend in the y-axis direction.

[0033] In the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182, the first transparent electrodes 181 and the second transparent electrodes 182 are alternately and repeatedly arranged along the x-axis direction. In the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184, the third transparent electrodes 183 and the fourth transparent electrodes 184 are alternately and repeatedly arranged along the x-axis direction.

[0034] The first substrate 111a and the second substrate 121a may be, for example, a rigid substrate having light-transmitting properties, such as a glass substrate, a quartz substrate, or a sapphire substrate. Alternatively, the first substrate 111a and the second substrate 121a may be, for example, a flexible substrate having light-transmitting properties, such as a polyimide resin substrate, an acrylic resin substrate, a siloxane resin substrate, or a fluororesin substrate.

[0035] The plurality of first transparent electrodes 181, the plurality of second transparent electrodes 182, the plurality of third transparent electrodes 183, and the plurality of fourth transparent electrodes 184 function as electrodes for forming an electric field in the liquid crystal layer 160a. The plurality of first transparent electrodes 181, the plurality of second transparent electrodes 182, the plurality of third transparent electrodes 183, and the plurality of fourth transparent electrodes 184 are made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0036] The first alignment film 114a and the second alignment film 124a align the long axes of the liquid crystal molecules in the liquid crystal layer 160a in a predetermined direction. When no voltage is applied to each transparent electrode, the liquid crystal molecules in the liquid crystal layer 160a are aligned based on the alignment characteristics of the first alignment film 114a or the second alignment film 124a. For convenience, the long axis direction of the liquid crystal molecules in the lighting device 100 is defined as the alignment direction of the liquid crystal molecules. The first alignment film 114a and the second alignment film 124a are made of a polyimide resin or the like. The first alignment film 114a and the second alignment film 124a may be imparted with alignment characteristics by alignment treatments such as rubbing or photo-alignment. The rubbing method involves rubbing the surface of the alignment film in one direction. The photo-alignment method involves irradiating the alignment film with linearly polarized ultraviolet light.

[0037] The first alignment film 114a is provided with an alignment characteristic such that the alignment direction of the liquid crystal molecules on the first substrate 111a side of the first liquid crystal cell 110a is perpendicular to the extension direction of the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182. The second alignment film 124a is provided with an alignment characteristic such that the alignment direction of the liquid crystal molecules on the second substrate 121a side of the first liquid crystal cell 110a is perpendicular to the extension direction of the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184. For convenience, in FIGS. 2 and 3 , the alignment direction of the liquid crystal molecules in the liquid crystal layer 160a is indicated using arrows and symbols with a cross inside a circle. The arrow indicates the alignment direction of the liquid crystal molecules aligned parallel to the paper, and the symbol with a cross inside a circle indicates the alignment direction of the liquid crystal molecules aligned perpendicular to the paper. The alignment direction of the liquid crystal molecules on the first substrate 111a side and the alignment direction of the liquid crystal molecules on the second substrate 121a side are the x-axis direction.

[0038] The liquid crystal layer 160a contains liquid crystal. The liquid crystal layer 160a can refract light passing through it or change the polarization of the light passing through it depending on the orientation direction of the liquid crystal molecules in the liquid crystal. Nematic liquid crystal or the like is used as the liquid crystal for the liquid crystal layer 160a. The liquid crystal described in this embodiment is positive-type, but it is also possible to use a negative-type liquid crystal instead of the positive-type liquid crystal by changing the orientation direction of the liquid crystal molecules when no voltage is applied to each transparent electrode. In addition, the liquid crystal preferably contains a chiral agent that imparts a twist to the liquid crystal molecules.

[0039] The second liquid crystal cell 110b includes a first substrate 111b, a second substrate 121b, a plurality of first transparent electrodes 181 (e.g., first transparent electrode 181-1b), a plurality of second transparent electrodes 182 (e.g., second transparent electrode 182-1b, second transparent electrode 182-2b), a plurality of third transparent electrodes 183 (e.g., third transparent electrode 183-1b, third transparent electrode 183-2b), a plurality of fourth transparent electrodes 184 (e.g., fourth transparent electrode 184-1b, fourth transparent electrode 184-2b), a first alignment film 114b, a second alignment film 124b, and a liquid crystal layer 160b. The first substrate 111b, the second substrate 121b, the plurality of first transparent electrodes 181 (for example, the first transparent electrode 181-1b), the plurality of second transparent electrodes 182 (for example, the second transparent electrode 182-1b, the second transparent electrode 182-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1b, the third transparent electrode 183-2b), the plurality of fourth transparent electrodes 184 (for example, the fourth transparent electrode 184-1b, the fourth transparent electrode 184-2b), the first alignment film 114b, the second alignment film 124b, and the liquid crystal layer 160b are each a first substrate. The second liquid crystal cell 110b has the same configuration and function as the plate 111a, the second substrate 121a, the plurality of first transparent electrodes 181 (e.g., the first transparent electrode 181-1a), the plurality of second transparent electrodes 182 (e.g., the second transparent electrode 182-1a, the second transparent electrode 182-2a), the plurality of third transparent electrodes 183 (e.g., the third transparent electrode 183-1a, the third transparent electrode 183-2a), the plurality of fourth transparent electrodes 184 (e.g., the fourth transparent electrode 184-1a, the fourth transparent electrode 184-2a), the first alignment film 114a, the second alignment film 124a, and the liquid crystal layer 160a. Therefore, the description of the second liquid crystal cell 110b will be omitted here.

[0040] In a plan view, the first transparent electrodes 181 provided in the first liquid crystal cell 110a and the second liquid crystal cell 110b are overlapped with each other so that their extending directions (y-axis direction) coincide with each other. Similarly, the transparent electrodes with the same name provided in the first liquid crystal cell 110a and the second liquid crystal cell 110b are overlapped with each other so that their extending directions (y-axis direction) coincide with each other. That is, the lighting device 100 includes a configuration in which liquid crystal cells (the first liquid crystal cell 110a and the second liquid crystal cell 110b) having the same configuration are overlapped with each other. As shown in FIGS. 2 and 3 , of the pair of upper and lower substrates constituting the first liquid crystal cell 110a and the second liquid crystal cell 110b, the lower substrates (substrates on the light source side) are the first substrates 111a and 111b.

[0041] As explained in "1-1. Configuration of the lighting device 100," the first liquid crystal cell 110a and the second liquid crystal cell 110b have the same basic configuration and function. Therefore, the first substrate 111a and the first substrate 111b, the second substrate 121a and the second substrate 121b, the plurality of first transparent electrodes 181 (for example, the first transparent electrode 181-1a, the first transparent electrode 181-1b), the plurality of second transparent electrodes 182 (for example, the second transparent electrode 182-1a, the second transparent electrode 182-2a, the second transparent electrode 182-1b, the second transparent electrode 182-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1a, the third transparent electrode 183-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1b, the third transparent electrode 183-2b), the plurality of second transparent electrodes 182 (for example, the second transparent electrode 182-1a, the second transparent electrode 182-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1a, the third transparent electrode 183-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1b ... second transparent electrodes 182 (for example, the second transparent electrode 182-1a, the second transparent electrode 182-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183-1b, the third transparent electrode 183-2b), the plurality of third transparent electrodes 183 (for example, the third transparent electrode 183 When distinguished, the first and second transparent electrodes 183-2a, 183-1b, and 183-2b, the second and third transparent electrodes 183-1a, 184-2a, 184-1b, and 184-2b, the third and fourth transparent electrodes 184 (for example, the fourth transparent electrode 184-1a, the fourth transparent electrode 184-2a, the fourth transparent electrode 184-1b, and 184-2b), the first and second alignment films 114a and 114b, the second and second alignment films 124a and 124b, and the liquid crystal layers 160a and 160b will be described using their respective names. When the components contained in the first liquid crystal cell 110a and the second liquid crystal cell 110b described above are not distinguished from one another, the components contained in the first liquid crystal cell 110a and the second liquid crystal cell 110b are described as a first substrate 111, a second substrate 121, a plurality of first transparent electrodes 181, a plurality of second transparent electrodes 182, a plurality of third transparent electrodes 183, a plurality of fourth transparent electrodes 184, a first alignment film 114, a second alignment film 124, and a liquid crystal layer 160.

[0042] <1-3. Arrangement of Transparent Electrodes> An outline of each electrode of the liquid crystal optical element 10 will be described with reference to FIGS. 1 and 4 to 6. FIG. 4 is a schematic plan view showing the arrangement of a plurality of first transparent electrodes 181 and a plurality of second transparent electrodes 182 on the first substrate 111 of the liquid crystal optical element 10. FIG. 5 is a schematic plan view showing the arrangement of a plurality of third transparent electrodes 183 and a plurality of fourth transparent electrodes 184 on the second substrate 121 of the liquid crystal optical element 10. FIG. 6 is a cross-sectional view showing the cross-sectional structure of a portion of the liquid crystal optical element 10. Note that FIG. 6 corresponds to the cross-sectional structure of the first liquid crystal cell 110a taken along line A1-A2 shown in FIG. 1. Configurations that are the same as or similar to those in FIGS. 1 to 3 will be described as necessary.

[0043] The cross-sectional structure of the first liquid crystal cell 110a is the same as that of the second liquid crystal cell 110b, and the cross-sectional structure of the first liquid crystal cell 110a will be described here, and the cross-sectional structure of the second liquid crystal cell 110b will be described as necessary.

[0044] First, an outline of each electrode of the liquid crystal optical element 10 in a planar view will be described with reference to Figures 1, 4, and 5. As shown in Figure 4, in a planar view, a plurality of first transparent electrodes 181, a plurality of second transparent electrodes 182, a first terminal 119-1, and a second terminal 119-2 are provided on a first substrate 111. In addition, a fifth wiring 116-5, a sixth wiring 116-6, a plurality of first power supply terminals 118-1, a plurality of second power supply terminals 118-2, a third terminal 119-3, and a fourth terminal 119-4 are provided on the first substrate 111.

[0045] The plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 are supplied with a control signal (electric potential) from the control device 40, and have the functions of transmitting, making it difficult to transmit, diffusing, and refracting the light emitted from the light source 30.

[0046] The plurality of first transparent electrodes 181 includes a first transparent electrode 181-1. The plurality of second transparent electrodes 182 includes a second transparent electrode 182-1 and a second transparent electrode 182-2. The major axes of the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 extend in the y-axis direction, and the first transparent electrodes 181 and the second transparent electrodes 182 are alternately arranged along the x-axis direction.

[0047] The electrode width of the first transparent electrode 181 and the electrode width of the second transparent electrode 182 (width in the x-axis direction) are the first width w １ The inter-electrode distance (electrode spacing) between the first transparent electrode 181 and the second transparent electrode 182 in the x-axis direction is the first inter-electrode distance p １ In the lighting device 100, the first width w １ is the first inter-electrode distance p １ but with a first width w １ is the first inter-electrode distance p １ The electrode width of the first transparent electrode 181 and the electrode width of the second transparent electrode 182 may be different.

[0048] The cell gap d is the first width w １ and the first inter-electrode distance p １ For example, the cell gap d is 8 μm≦d≦50 μm, preferably 10 μm≦d≦30 μm, and more preferably 15 μm≦d≦25 μm. For example, the cell gap d of the lighting device 100 is 30 μm, and the first width w １ and the first inter-electrode distance p １ Therefore, the transverse electric field generated on the first substrate 111a side and the second substrate 112a side affects the liquid crystal molecules located near the center between the first substrate 111a and the second substrate 112a, and the lighting device 100 can bend the incident light 180.

[0049] The plurality of first transparent electrodes 181 are electrically connected to the first wirings 116-1, and the first wirings 116-1 are electrically connected to the first terminals 119-1. The first wirings 116-1 may be formed below the plurality of first transparent electrodes 181 or above the plurality of first transparent electrodes 181. Furthermore, the first wirings 116-1 may be formed in the same layer as the plurality of first transparent electrodes 181. The plurality of second transparent electrodes 182 are electrically connected to the second wirings 116-2, and the second wirings 116-2 are electrically connected to the second terminals 119-2. The second wirings 116-2 may be formed below the plurality of second transparent electrodes 182 or above the plurality of second transparent electrodes 182. Furthermore, the second wirings 116-2 may be formed in the same layer as the plurality of second transparent electrodes 182. For example, the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 of the lighting device 100 are formed in the same layer as the first wiring 116-1 and the second wiring 116-2.

[0050] The fifth wiring 116-5 is electrically connected to the plurality of first power supply terminals 118-1 and the first terminal 119-1, and the sixth wiring 116-6 is electrically connected to the plurality of second power supply terminals 118-2 and the fourth terminal 119-4.

[0051] The first alignment film 114 disposed on the first substrate 111 is aligned in the x-axis direction (the direction indicated by the hollow arrow in FIG. 4 ). In this case, the long axes of the liquid crystal molecules constituting the liquid crystal layer 160 on the first substrate 111 side are aligned along the x-axis direction. That is, the alignment direction of the first alignment film 114 (x-axis direction) and the extension direction (y-axis direction) of the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 are perpendicular to each other.

[0052] As shown in FIG. 5, in a plan view, a plurality of third transparent electrodes 183, a plurality of fourth transparent electrodes 184, a third wiring 116-3, a fourth wiring 116-4, a plurality of third power supply terminals 118-3, and a plurality of fourth power supply terminals 118-4 are provided on a second substrate 121.

[0053] The plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184, like the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182, are supplied with a control signal (electric potential) from the control device 40, and have the functions of transmitting, making it difficult to transmit, diffusing, and refracting light emitted from the light source 30.

[0054] The plurality of third transparent electrodes 183 include a third transparent electrode 183-1 and a third transparent electrode 183-2. The plurality of fourth transparent electrodes 184 include a fourth transparent electrode 184-1 and a fourth transparent electrode 184-2. The major axes of the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184 extend in the y-axis direction, and the third transparent electrodes 183 and the fourth transparent electrodes 184 are alternately arranged along the x-axis direction. The electrode width of the third transparent electrode 183 and the electrode width of the fourth transparent electrode 184 (width in the x-axis direction) are equal to or larger than the second width w ２ The inter-electrode distance (electrode spacing) between the third transparent electrode 183 and the fourth transparent electrode 184 in the x-axis direction is ２ is.

[0055] In the lighting device 100, the second width w ２ is the first width w １ Wider (thicker), the second inter-electrode distance p ２ is the first inter-electrode distance p １ The electrode width of the third transparent electrode 183 and the electrode width of the fourth transparent electrode 184 may be different.

[0056] The plurality of third transparent electrodes 183 are electrically connected to the third wirings 116-3, and the third wirings 116-3 are electrically connected to the plurality of third power supply terminals 118-3. The plurality of fourth transparent electrodes 184 are electrically connected to the fourth wirings 116-4, and the fourth wirings 116-4 are electrically connected to the plurality of fourth power supply terminals 118-4. The third wirings 116-3 may be formed below the plurality of third transparent electrodes 183 or above the plurality of third transparent electrodes 183. Furthermore, the third wirings 116-3 may be formed in the same layer as the plurality of third transparent electrodes 183. The fourth wirings 116-4 may be formed below the plurality of fourth transparent electrodes 184 or above the plurality of fourth transparent electrodes 184. Furthermore, the fourth wirings 116-4 may be formed in the same layer as the plurality of fourth transparent electrodes 184. For example, the plurality of third transparent electrodes 183, the plurality of fourth transparent electrodes 184, the third wirings 116-3, and the fourth wirings 116-4 of the lighting device 100 are formed in the same layer. Note that the third wirings 116-3, the plurality of third power supply terminals 118-3, the fourth wirings 116-4, and the plurality of fourth power supply terminals 118-4 may be formed in the same layer as the third wirings 116-3 and the fourth wirings 116-4, similar to the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184.

[0057] In the liquid crystal cell 110, the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 face the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184 via the liquid crystal layer 160a. The extending direction (y-axis direction) of the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 is parallel to the extending direction (y-axis direction) of the plurality of third transparent electrodes 183 and the plurality of fourth transparent electrodes 184.

[0058] When the first substrate 111 is bonded to the second substrate 121, each of the multiple first power supply terminals 118-1 is electrically connected to the corresponding third power supply terminal 118-3, and each of the multiple second power supply terminals 118-2 is electrically connected to the corresponding fourth power supply terminal 118-4. As a result, the first wiring 116-1 is electrically connected to the third wiring 116-3, and the second wiring 116-2 is electrically connected to the fourth wiring 116-4. For example, the first power supply terminal 118-1 and the third power supply terminal 118-3, and the second power supply terminal 118-2 and the fourth power supply terminal 118-4 can be electrically connected using silver paste or conductive particles. Note that the conductive particles include particles coated with a metal.

[0059] 1, 4, and 5, the length of the second substrate 121 along the x-axis direction is shorter than the length of the first substrate 111 along the x-axis direction. The first terminal 119-1, the second terminal 119-2, the third terminal 119-3, and the fourth terminal 119-4 are provided on the terminal portion 12 on the first substrate 111. As a result, when the first substrate 111 is bonded to the second substrate 121, the first terminal 119-1, the second terminal 119-2, the third terminal 119-3, and the fourth terminal 119-4 are exposed and not covered by the second substrate 121.

[0060] Therefore, in the first liquid crystal cell 110a, the terminal portion 12a can be easily attached to the first flexible wiring board 11a and easily electrically connected. As a result, the plurality of first transparent electrodes 181 receive a control signal (electric potential) from the control device 40 (see FIG. 1 ) via the first flexible wiring board 11a, the terminal portion 12a, the first terminal 119-1, and the first wiring 116-1. The plurality of second transparent electrodes 182 receive a control signal (electric potential) from the control device 40 via the first flexible wiring board 11a, the terminal portion 12a, the second terminal 119-2, and the second wiring 116-2. The plurality of third transparent electrodes 183 receive a control signal (electric potential) from the control device 40 via the first flexible wiring substrate 11a, the terminal portion 12a, the third terminal 119-3, the fifth wiring 116-5, the plurality of first power supply terminals 118-1, the third wiring 116-3, and the plurality of third power supply terminals 118-3. The plurality of fourth transparent electrodes 184 receive a control signal (electric potential) from the control device 40 via the first flexible wiring substrate 11a, the terminal portion 12a, the fourth terminal 119-4, the sixth wiring 116-6, the plurality of second power supply terminals 118-2, the fourth wiring 116-4, and the plurality of fourth power supply terminals 118-4. Similar to the first liquid crystal cell 110a, the terminal portion 12b of the second liquid crystal cell 110b can also be easily attached to the second flexible wiring substrate 11b and easily electrically connected. Similarly to the first liquid crystal cell 110 a, the control signal (potential) is also supplied from the control device 40 to each electrode in the second liquid crystal cell 110 b.

[0061] Note that a photospacer (not shown) may be formed on the side of the first substrate 111 facing the second substrate 121, or on the side of the second substrate 121 facing the first substrate 111. By including the photospacer, the lighting device 100 can maintain a constant distance between the first substrate 111 and the second substrate 121.

[0062] A metal material can be used as a material for forming the first wiring 116-1, the second wiring 116-2, the third wiring 116-3, the fourth wiring 116-4, the fifth wiring 116-5, the sixth wiring 116-6, the plurality of first power supply terminals 118-1, the plurality of third power supply terminals 118-3, the plurality of second power supply terminals 118-2, the plurality of fourth power supply terminals 118-4, the first terminal 119-1, the second terminal 119-2, the third terminal 119-3, and the fourth terminal 119-4. Examples of the metal material include aluminum and molybdenum. For example, when the material forming the first wiring 116-1, the second wiring 116-2, the first terminal 119-1, and the second terminal 119-2 is a metal material, the material forming the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 may be ITO or IZO, and the plurality of first transparent electrodes 181 may be arranged so as to overlap on the first wiring 116-1 (the side opposite to the first substrate 111), and the plurality of second transparent electrodes 182 may be arranged so as to overlap on the second wiring 116-2 (the side opposite to the first substrate 111). When the material forming the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 is ITO or IZO, the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 have high resistance to corrosion. By arranging a plurality of first transparent electrodes 181 and a plurality of second transparent electrodes 182, which are highly resistant to corrosion, on the first wiring 116-1, the second wiring 116-2, the first terminal 119-1, and the second terminal 119-2 (on the opposite side from the first substrate 111) which are made of a metal material, corrosion of the first wiring 116-1, the second wiring 116-2, the first terminal 119-1, and the second terminal 119-2 can be suppressed.

[0063] Next, with reference to FIG. 6, the cross-sectional structure of a portion of the liquid crystal optical element 10 will be described.

[0064] The first transparent electrode 181-1a is sandwiched between two adjacent second transparent electrodes 182-1a and 182-2a. The first transparent electrode 181-1a overlaps along the z-axis with the end of the fourth transparent electrode 184-1a on the third transparent electrode 183-2a side, the space between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a, and the end of the third transparent electrode 183-2a on the fourth transparent electrode 184-1a side.

[0065] The space between the first transparent electrode 181-1a and the second transparent electrode 182-1a overlaps with the fourth transparent electrode 184-1a along the z-axis direction, and the space between the first transparent electrode 181-1a and the second transparent electrode 182-2a overlaps with the third transparent electrode 183-2a along the z-axis direction.

[0066] The second transparent electrode 182-1a overlaps along the z-axis direction with the end of the third transparent electrode 183-1a on the side of the fourth transparent electrode 184-1a, the space between the third transparent electrode 183-1a and the fourth transparent electrode 184-1a, and the end of the fourth transparent electrode 184-1a on the side of the third transparent electrode 183-1a.

[0067] The second transparent electrode 182-2a is configured in the same manner as the second transparent electrode 182-1a.

[0068] The third transparent electrode 183-2a is sandwiched between two adjacent fourth transparent electrodes 184-1a and 184-2a. The fourth transparent electrode 184-1a is sandwiched between two adjacent third transparent electrodes 183-1a and 183-2a.

[0069] The first liquid crystal cell 110a includes a plurality of first regions ZN1 and a plurality of second regions ZN2, which are alternately arranged along the x-axis direction.

[0070] The first region ZN1 is adjacent to the second region ZN2. The first region ZN1 also includes a region along the z-axis direction where the space between the first transparent electrode 181-1a and the second transparent electrode 182-1a overlaps with the fourth transparent electrode 184-1a. The first region ZN1 also includes a region along the z-axis direction where the space between the first transparent electrode 181-1a and the second transparent electrode 182-2a overlaps with the third transparent electrode 183-2a. Width OV ２ is the width of the overlap of the first transparent electrode 181-1a with the end of the fourth transparent electrode 184-1a on the third transparent electrode 183-2a side along the z-axis direction. ３ is the width along the z-axis direction where the first transparent electrode 181-1a overlaps with the end of the third transparent electrode 183-2a on the fourth transparent electrode 184-1a side.

[0071] The second region ZN2 includes, along the z-axis direction, a region where the first transparent electrode 181-1a overlaps with the end of the fourth transparent electrode 184-1a on the side of the third transparent electrode 183-2a, a region where the first transparent electrode 181-1a overlaps with the space between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a, and a region where the first transparent electrode 181-1a overlaps with the end of the third transparent electrode 183-2a on the side of the fourth transparent electrode 184-1a. The second region ZN2 includes, along the z-axis direction, a region where the second transparent electrode 182-2a overlaps with the end of the third transparent electrode 183-2a on the side of the fourth transparent electrode 184-2a, a region where the second transparent electrode 182-2a overlaps with the space between the third transparent electrode 183-2a and the fourth transparent electrode 184-2a, and a region where the second transparent electrode 182-2a overlaps with the end of the fourth transparent electrode 184-2a on the side of the third transparent electrode 183-2a. ４ is the width of the second transparent electrode 182-2a overlapping with the end of the third transparent electrode 183-2a on the fourth transparent electrode 184-2a side along the z-axis direction. １ may be a width along the z-axis direction such that the second transparent electrode 182-1a overlaps with the end of the fourth transparent electrode 184-1a on the side of the third transparent electrode 183-1a, and may be a width along the z-axis direction such that the second transparent electrode 182-2a overlaps with the end of the fourth transparent electrode 184-2a on the side of the third transparent electrode 183-2a.

[0072] The cell gap d may be the distance between the surface where the liquid crystal layer 160 a and the first alignment film 114 a contact each other and the surface where the liquid crystal layer 160 a and the first alignment film 114 a contact each other, or may be the distance between the first substrate 111 a and the second substrate 121 a. For example, the cell gap d of the lighting device 100 is the distance between the surface where the liquid crystal layer 160 a and the first alignment film 114 a contact each other and the surface where the liquid crystal layer 160 a and the first alignment film 114 a contact each other.

[0073] <1-4. Control of Light Distribution by Liquid Crystal Optical Element 10> Light distribution using the liquid crystal optical element 10 will be described with reference to FIGS. 7 to 13. FIG. 7 corresponds to the cross-sectional structure of the first liquid crystal cell 110a and the second liquid crystal cell 110b taken along line A1-A2 in FIG. 1. FIGS. 8 and 10 are cross-sectional views showing the orientation of liquid crystal in the liquid crystal layer in the liquid crystal cell. FIGS. 9 and 11 are diagrams showing the relationship between each region in the liquid crystal cell and the phase difference. FIG. 12 is a timing chart showing the voltages supplied to each terminal included in the liquid crystal optical element 10. FIG. 13 is a schematic diagram for explaining the direction of light distribution in the lighting device 100. Configurations that are the same as or similar to those in FIGS. 1 to 6 will be described as necessary.

[0074] In the first liquid crystal cell 110a, the first alignment film 114a is aligned in the x-axis direction, away from the terminal 12 (see FIG. 4). The second alignment film 124a is aligned in the x-axis direction, away from the terminal 12 (see FIG. 5). Therefore, the long axes of the liquid crystal molecules on the first substrate 111a side and the long axes of the liquid crystal molecules on the second substrate 121a side are aligned in the x-axis direction. The first alignment film 114b, the second alignment film 124b, and the liquid crystal molecules in the liquid crystal layer 160b of the second liquid crystal cell 110b are configured in the same manner as in the first liquid crystal cell 110a.

[0075] First, referring to Figure 7, the liquid crystal optical element 10 will be described in a state where no potential is supplied to the transparent electrodes of the first liquid crystal cell 110a and the second liquid crystal cell 110b. Figure 7 shows the liquid crystal optical element 10 in a state where no potential is supplied to the first transparent electrodes 181-1a and 181-1b, the second transparent electrodes 182-1a, 182-2a, 182-1b, and 182-2b, the third transparent electrodes 183-1a, 183-2a, 183-1b, and 183-2b, and the fourth transparent electrodes 184-1a, 184-2a, 184-1b, and 184-2b. The adhesive layers 130a and 130b are omitted from Figure 7.

[0076] As shown in Figure 7, the light emitted from the light source has a polarized component in the x-axis direction (P-polarized component) and a polarized component in the y-axis direction (S-polarized component). However, for convenience, the light will be described here as being divided into P-polarized and S-polarized components. The light emitted from the light source (see (1) in Figure 7) includes a first polarized light 61 having a P-polarized component and a second polarized light 62 having an S-polarized component. The arrow symbol and the circle symbol with a cross in Figure 7 represent the P-polarized component and the S-polarized component, respectively. The arrow symbol indicates that the light is parallel to the x-axis, and the circle symbol with a cross indicates that the light is parallel to the y-axis. The light emitted from the light source is light (incident light 180) that enters the liquid crystal optical element 10.

[0077] After entering the first substrate 111a, the first polarized light 61 maintains its P-polarized component and exits from the second substrate 121a (see (2) and (3) in FIG. 7). After entering the wave plate 140, the first polarized light 61 changes from a P-polarized component to an S-polarized component as it travels toward the second liquid crystal cell 110b due to the phase difference λ / 2 of the wave plate 140 (see (5) in FIG. 7). After entering the first substrate 111b, the first polarized light 61 maintains its S-polarized component and exits from the second substrate 121a (see (6) to (8) in FIG. 7).

[0078] After entering the first substrate 111a, the second polarized light 62 maintains its S-polarized component and exits from the second substrate 121a side (see (2) and (3) in FIG. 7). After entering the wave plate 140, the second polarized light 62 changes from an S-polarized component to a P-polarized component as it travels toward the second liquid crystal cell 110b due to the phase difference λ / 2 of the wave plate 140 (see (5) in FIG. 7). After entering the first substrate 111b, the second polarized light 62 maintains its P-polarized component and exits from the second substrate 121a side (see (5) to (8) in FIG. 7).

[0079] The liquid crystal optical element 10 has a structure in which two liquid crystal cells (a first liquid crystal cell 110a and a second liquid crystal cell 110b) having the same structure are stacked, and changes the polarization component of light incident on the liquid crystal optical element 10 by one degree. As a result, the liquid crystal optical element 10 can change the polarization component before and after incidence (see (1) to (8) in FIG. 7). In other words, the liquid crystal optical element 10 can rotate the polarization component of the incident light 180 and the polarization component of the outgoing light by 90 degrees.

[0080] 8 to 13, the liquid crystal optical element 10 will be described in a state where a potential is applied to each transparent electrode of the first liquid crystal cell 110a. Note that the configuration and function of the second liquid crystal cell 110b are similar to those of the first liquid crystal cell 110a, and therefore will be described as necessary.

[0081] When different control signals (potentials) are supplied from the control device 40 to adjacent first transparent electrodes 181 and second transparent electrodes 182 among the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182, a potential difference occurs between the adjacent first transparent electrodes 181 and second transparent electrodes 182. As a result, an electric field (first electric field) is generated between the adjacent first transparent electrodes 181 and second transparent electrodes 182. As with the first transparent electrodes 181 and second transparent electrodes 182, when different control signals (potentials) are supplied from the control device 40 to adjacent third transparent electrodes 183 and fourth transparent electrodes 184, a potential difference occurs between the adjacent third transparent electrodes 183 and fourth transparent electrodes 184, an electric field (second electric field) is generated between the adjacent third transparent electrodes 183 and fourth transparent electrodes 184. For example, the first electric field and the second electric field are called transverse electric fields.

[0082] Furthermore, a potential difference is generated between the opposing first transparent electrode 181 and third transparent electrode 183, and between the opposing second transparent electrode 182 and fourth transparent electrode 184. As a result, an electric field (third electric field, fourth electric field) is generated between the opposing first transparent electrode 181 and third transparent electrode 183, and between the opposing second transparent electrode 182 and fourth transparent electrode 184. Note that, since the same control signal (potential) is supplied between the opposing first transparent electrode 181 and fourth transparent electrode 184, and between the opposing second transparent electrode 182 and third transparent electrode 183, no potential difference is generated.

[0083] For example, as shown in FIGS. 8 and 12, a low potential VL is supplied to the second transparent electrode 182-1a, the second transparent electrode 182-2a, the third transparent electrode 183-1a, and the third transparent electrode 183-2a, and a high potential VH is supplied to the first transparent electrode 181-1a, the fourth transparent electrode 184-1a, and the fourth transparent electrode 184-2a. As a result, a potential difference (VH-VL) occurs between the second transparent electrode 182-1a and the first transparent electrode 181-1a, generating a lateral electric field. Similarly, a potential difference (VH-VL) occurs between other adjacent electrodes, generating a lateral electric field. For example, the high potential VH is greater (higher) than the low potential VL, and the high potential VH is a potential with the polarity reversed from that of the low potential VL. Furthermore, the mid potential VM is a reference potential and may be ground or 0 V. For example, the absolute value of the potential difference between the high potential VH and the intermediate potential VM is the same as the absolute value of the potential difference between the low potential VL and the intermediate potential.

[0084] Furthermore, potential differences (VH-VL) are generated between the second transparent electrode 182-1a and the fourth transparent electrode 184-1a, between the first transparent electrode 181-1a and the third transparent electrode 183-2a, and between the second transparent electrode 182-2a and the fourth transparent electrode 184-2a, and an electric field is generated. Note that no potential differences are generated between the first transparent electrode 181-1a and the fourth transparent electrode 184-1a, and between the second transparent electrode 182-2a and the third transparent electrode 183-2a, and therefore no electric field is generated.

[0085] When an electric field is generated, the alignment state of the liquid crystal molecules in the liquid crystal layer 160a that are affected by the electric field changes.

[0086] First, the orientation state of the liquid crystal molecules in the first region ZN1 will be described. The long axes of the liquid crystal molecules on the first substrate 111a side are oriented in a convex arc shape in the x-axis direction based on the lateral electric field between the second transparent electrode 182-1a and the first transparent electrode 181-1a. Furthermore, as they move from the first substrate 111a toward the second substrate 121a, the long axes of the liquid crystal molecules are oriented with a tilt from the x-axis direction to the z-axis direction based on the electric field between the second transparent electrode 182-1a and the fourth transparent electrode 184-1a. Note that the long axes of the liquid crystal molecules may also be oriented with a tilt from the x-axis direction to the z-axis direction due to the influence of the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a.

[0087] Furthermore, the long axes of the liquid crystal molecules on the first substrate 111a side are aligned in a convex arc shape in the x-axis direction based on the transverse electric field between the second transparent electrode 182-1a and the first transparent electrode 181-1a. Furthermore, as they move from the first substrate 111a to the second substrate 121a, the long axes of the liquid crystal molecules are aligned so as to be tilted from the x-axis direction to the z-axis direction based on the electric field between the second transparent electrode 182-1a and the fourth transparent electrode 184-1a. Note that the long axes of the liquid crystal molecules may also be aligned so as to be tilted from the x-axis direction to the z-axis direction under the influence of the transverse electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a.

[0088] As a result, for example, the first polarized light 61 incident on the first region ZN1 is bent at the control angle θ from the second transparent electrode 182-1a toward the fourth transparent electrode 184-1a. The first polarized light 61 incident on the first region ZN1 is bent at the control angle θ from the first transparent electrode 181-1a toward the third transparent electrode 183-2a. For example, the control angle θ is the angle between the major axis of the liquid crystal molecule and the incident surface 63 in a cross-sectional view.

[0089] Next, the orientation state of the liquid crystal molecules in the second region ZN2 will be described. For example, because no electric field is generated between the first transparent electrode 181-1a and the fourth transparent electrode 184-1a, the long axes of the liquid crystal molecules are oriented parallel to the x-axis. In reality, the long axes of the liquid crystal molecules may be oriented tilted from the x-axis direction toward the z-axis direction due to the influence of the lateral electric field between the second transparent electrode 182-1a and the first transparent electrode 181-1a and the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a. Furthermore, the long axes of the liquid crystal molecules are oriented along the z-axis direction based on the electric field between the first transparent electrode 181-1a and the third transparent electrode 183-2a. Note that the long axes of the liquid crystal molecules may be oriented tilted from the z-axis direction toward the x-axis direction due to the influence of the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a. As a result, for example, the first polarized light 61 incident on the second region ZN2 may travel generally straight from the second transparent electrode 182-1a to the fourth transparent electrode 184-1a and may be tilted from the z-axis direction to the x-axis direction.

[0090] Furthermore, for example, since no electric field is generated between the second transparent electrode 182-1a and the third transparent electrode 183-2a, the long axes of the liquid crystal molecules are oriented parallel to the x-axis. In reality, the long axes of the liquid crystal molecules may be oriented tilted from the x-axis direction toward the z-axis direction due to the influence of the lateral electric field between the second transparent electrode 182-2a and the first transparent electrode 181-1a and the lateral electric field between the fourth transparent electrode 184-2a and the third transparent electrode 183-2a. Furthermore, the long axes of the liquid crystal molecules are oriented along the z-axis direction based on the electric field between the second transparent electrode 182-2a and the fourth transparent electrode 184-2a. Note that the long axes of the liquid crystal molecules may be oriented tilted from the z-axis direction toward the x-axis direction due to the influence of the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a. As a result, for example, the first polarized light 61 incident on the second region ZN2 may travel generally straight from the second transparent electrode 182-2a to the fourth transparent electrode 184-2a and tilt from the z-axis direction to the x-axis direction.

[0091] The orientation of the liquid crystal in each region shown in Figure 8 can be shown as the relationship between each region and the retardation, as shown in Figure 9. In this specification and drawings, the retardation is expressed as the product of the cell gap d and the coefficient Δn, i.e., Δnd, using the cell gap d and the coefficient Δn. Furthermore, the control angle θ can be adjusted depending on the potential supplied to each electrode. For example, the control angle θ in Figures 8 and 9 is smaller than 90 degrees.

[0092] As shown in FIG. 9 , the phase difference of light incident on the first region ZN1 gradually increases as it travels from the first substrate 111a side to the second substrate 121a side. The increase in phase difference means that the light is emitted from the first substrate 111a side to the second substrate 121a side. That is, the light incident on the first region ZN1 is bent as it travels from the first substrate 111a side to the second substrate 121a side and is emitted from the second substrate 121a. Furthermore, the phase difference of light incident on the second region ZN2 increases slightly and then decreases as it travels from the first substrate 111a side to the second substrate 121a side. The decrease in phase difference means that the light travels from the second substrate 121a side to the first substrate 111a side and is not emitted from the second substrate 121a. That is, the light incident on the second region ZN2 is not emitted from the second substrate 121a.

[0093] As shown in Figures 8 and 9, by supplying a high potential VH or a low potential VL to each electrode of the lighting device 100, the lighting device 100 can bend light (e.g., incident light 180 (see Figure 1)) incident on the incident surface 63 of the first liquid crystal cell 110a at a control angle θ and emit the light from the first liquid crystal cell 110a. Also, as schematically shown in Figure 13, the bent light emitted from the first liquid crystal cell 110a passes through the wave plate 140 and the second liquid crystal cell 110b and is emitted from the second liquid crystal cell 110b. The first polarized light 61 incident on the incident surface 63 of the first liquid crystal cell 110a is bent, rotated 90 degrees by the wave plate 140, transmitted through the second liquid crystal cell 110b, and emitted from the liquid crystal optical element 10. Since the second polarized light 62 is rotated by 90 degrees relative to the first polarized light 61, it passes through the first liquid crystal cell 110a, is rotated by 90 degrees by the wave plate 140, and is then bent by the second liquid crystal cell 110b in the same manner as the first polarized light 61, and is emitted from the liquid crystal optical element 10. Note that the diagram shown in Fig. 13 is a schematic diagram of the lighting device 100, and in reality, the first polarized light 61 and the second polarized light 62 are rotated by 90 degrees.

[0094] For example, when the cell gap d is 30 μm and the distance between the first electrodes p １When the high potential VH and the low potential VL are set under the conditions of a tangent length of 35 μm and a Δn of 0.2, the control angle θ is 10 degrees. That is, under these conditions, the lighting device 100 can bend light incident on the incident surface 63 of the first liquid crystal cell 110a at an angle of 10 degrees and emit it from the first liquid crystal cell 110a. Furthermore, the lighting device 100 can rotate the light bent at an angle of 10 degrees that is emitted from the first liquid crystal cell 110a by 90 degrees using the wave plate 140, transmit the light through the second liquid crystal cell 110b, and emit it from the liquid crystal optical element 10 (second liquid crystal cell 110b). Furthermore, the lighting device 100 can transmit the light incident on the incident surface 63 of the first liquid crystal cell 110a through the first liquid crystal cell 110a and emit it from the first liquid crystal cell 110a. Furthermore, the lighting device 100 can rotate the light emitted from the first liquid crystal cell 110a by 90 degrees using the wave plate 140, and then bend the light at an angle of 10 degrees using the second liquid crystal cell 110b, causing the light to be emitted from the liquid crystal optical element 10 (second liquid crystal cell 110b).

[0095] 10 and 12, for example, a high potential VH(+) is supplied to the second transparent electrode 182-1a, the second transparent electrode 182-2a, the fourth transparent electrode 184-1a, and the fourth transparent electrode 184-2a, and a low potential VL(-) is supplied to the first transparent electrode 181-1a, the third transparent electrode 183-1a, and the third transparent electrode 183-2a. As a result, a potential difference (VH-VL) is generated between the second transparent electrode 182-1a and the first transparent electrode 181-1a, and a transverse electric field is generated. Similarly, potential differences (VH-VL) are generated between the other adjacent electrodes, and a transverse electric field is generated.

[0096] Furthermore, potential differences (VH-VL) are generated between the second transparent electrode 182-1a and the fourth transparent electrode 184-1a, between the first transparent electrode 181-1a and the third transparent electrode 183-2a, and between the second transparent electrode 182-2a and the fourth transparent electrode 184-2a, and electric fields are generated. Note that no potential differences are generated between the second transparent electrode 182-1a and the third transparent electrode 183-1a, between the first transparent electrode 181-1a and the fourth transparent electrode 184-1a, and between the second transparent electrode 182-2a and the third transparent electrode 183-2a, and no electric fields are generated.

[0097] When an electric field is generated, the alignment state of the liquid crystal molecules in the liquid crystal layer 160a that are affected by the electric field changes.

[0098] The configuration shown in Figure 10 is the opposite of the configuration shown in Figure 8 in the polarity of the potential supplied to the second transparent electrode 182-1a, the second transparent electrode 182-2a, and the first transparent electrode 181-1a. Therefore, the direction in which the liquid crystal molecules are oriented in each region of the configuration shown in Figure 10 is symmetrical in the z-axis direction to the direction in which the liquid crystal molecules are oriented in each region of the configuration shown in Figure 8. An example of the direction in which the liquid crystal molecules are oriented in each region of the configuration shown in Figure 10 will be described below, but the direction in which the liquid crystal molecules are oriented in each region of the configuration shown in Figure 10 that is not described below is symmetrical in the z-axis direction to the direction in which the liquid crystal molecules are oriented in each region of the configuration shown in Figure 8.

[0099] For example, the orientation state of liquid crystal molecules in the first region ZN1 will be described. The long axes of the liquid crystal molecules on the first substrate 111a side are oriented in a convex arc shape in the x-axis direction based on the lateral electric field between the second transparent electrode 182-1a and the first transparent electrode 181-1a. Furthermore, as they move from the first substrate 111a to the second substrate 121a, the long axes of the liquid crystal molecules are oriented with an inclination from the x-axis direction to the z-axis direction based on the electric field between the first transparent electrode 181-1a and the fourth transparent electrode 184-1a. Note that the long axes of the liquid crystal molecules may also be oriented with an inclination from the x-axis direction to the z-axis direction due to the influence of the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-1a.

[0100] As a result, for example, the first polarized light 61 incident on the first region ZN1 is bent at the control angle θ from the first transparent electrode 181-1a toward the fourth transparent electrode 184-1a. Also, the first polarized light 61 incident on the first region ZN1 is bent at the control angle θ from the second transparent electrode 182-3a toward the third transparent electrode 183-2a.

[0101] For example, the orientation state of the liquid crystal molecules in the second region ZN2 will be described. Because no electric field is generated between the first transparent electrode 181-1a and the third transparent electrode 183-2a, the long axes of the liquid crystal molecules are oriented parallel to the x-axis. In reality, the long axes of the liquid crystal molecules may be oriented tilted from the x-axis direction toward the z-axis direction due to the influence of the lateral electric field between the second transparent electrode 182-2a and the first transparent electrode 181-1a and the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a. Furthermore, the long axes of the liquid crystal molecules are oriented along the z-axis direction based on the electric field between the first transparent electrode 181-1a and the fourth transparent electrode 184-1a. Note that the long axes of the liquid crystal molecules may be oriented tilted from the z-axis direction toward the x-axis direction due to the influence of the lateral electric field between the fourth transparent electrode 184-1a and the third transparent electrode 183-2a. As a result, for example, the first polarized light 61 incident on the second region ZN2 may travel in a generally straight line from the first transparent electrode 181-1a to the fourth transparent electrode 184-1a, and may be tilted from the z-axis direction to the x-axis direction. Furthermore, for example, the material forming the plurality of first transparent electrodes 181 and the plurality of second transparent electrodes 182 may not be a transparent material but may be an opaque material, such as a metal material such as aluminum or molybdenum. In this case, the first polarized light 61 incident on the second region ZN2 travels in a generally straight line from the first transparent electrode 181-1a side to the fourth transparent electrode 184-1a side, and therefore only bent light is emitted.

[0102] The orientation of the liquid crystal in each region shown in FIG. 10 can be shown as the relationship between each region and the retardation, as shown in FIG. 11 . The direction in which the liquid crystal molecules are aligned in each region of the configuration shown in FIG. 10 is symmetrical in the z-axis direction to the direction in which the liquid crystal molecules are aligned in each region of the configuration shown in FIG. 8 . Therefore, the relationship between each region and the retardation shown in FIG. 11 is the inverse of the slope of the line in the relationship between each region and the retardation shown in FIG. 9 . That is, in the first region ZN1 shown in FIG. 9 , the retardation increases as one moves from the first region ZN1 to the second region ZN2, whereas in the first region ZN1 shown in FIG. 11 , the retardation increases as one moves from the second region ZN2 to the first region ZN1. The retardation of the second region shown in FIG. 11 is the inverse of the slope of the line in the retardation of the second region shown in FIG. 9 , similar to the retardation of the first region ZN1 shown in FIG. 11 .

[0103] That is, the configurations shown in Figures 10 and 11 bend light in the direction opposite to the x-axis direction of the configurations shown in Figures 8 and 9. For example, the control angle θ in the configuration shown in Figure 8 is smaller than 90 degrees, while the control angle θ in the configuration shown in Figure 10 is larger than 90 degrees. For example, the lighting device 100 with the configuration shown in Figure 10 can bend light to the left by using the conditions under which the lighting device 100 with the configuration shown in Figure 8 bends light to the right.

[0104] As described above, the lighting device 100 can emit light bent at the control angle θ from the liquid crystal optical element 10. Furthermore, by supplying a potential to each electrode included in the liquid crystal optical element 10, the lighting device 100 can emit light bent at the control angle θ corresponding to the supplied potential from the liquid crystal optical element 10. Thus, the lighting device 100 can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 10, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0105] 1-5. Configuration of Light Source 30 Figures 14 and 15 are schematic diagrams showing the light source 30. For example, as shown in Figure 14, the light source 30 may include a light-emitting element 31 and a reflector 32, and as shown in Figure 15, the light source 30 may include a light-emitting element 31 and a convex lens 33. Note that the configuration and function of the light source are not limited to the configuration and function of the light source 30. For example, the light source 30 may have a configuration that allows the light distribution to have a narrow angle.

[0106] For example, the light-emitting element 31 is an LED. The reflector 32 can reflect the light emitted from the light-emitting element 31 and emit the reflected light toward the liquid crystal optical element 10. Although the shape of the reflector 32 shown in Fig. 15 is approximately conical, the shape of the reflector 32 is not limited to approximately conical. Furthermore, the surface of the reflector 32 may be flat or curved. The convex lens 33 can collect the light emitted from the light-emitting element 31 and emit the collected light toward the liquid crystal optical element 10.

[0107] Second Embodiment An outline of the configuration of an illumination device 200 according to a second embodiment will be described with reference to FIGS. 16 to 25. FIG. 16 is a schematic perspective view showing the configuration of the illumination device 200. Compared to the illumination device 100, the illumination device 200 does not include a wave plate 140, and differs in the configuration of each electrode on the first substrate and the configuration of each electrode on the second substrate. The other configuration of the illumination device 200 is similar to the configuration of the illumination device 100. Therefore, configurations similar to those of the illumination device 100 will be described as necessary. Furthermore, configurations that are the same as or similar to those in FIGS. 1 to 15 will be described as necessary.

[0108] 2-1. Configuration of the Illumination Device 200> The configuration of the illumination device 200 will be outlined with reference to Fig. 16. Fig. 16 is a schematic perspective view showing the configuration of the illumination device 200.

[0109] 16 , the lighting device 200 includes a liquid crystal optical element 20, a light source 30, and a control device 40. As will be described in detail later, the liquid crystal optical element 20 includes a first liquid crystal cell 210a, an adhesive layer 230a, and a second liquid crystal cell 210b. The adhesive layer 230a is provided between the first liquid crystal cell 210a and the second liquid crystal cell 210b. The first liquid crystal cell 210a, the adhesive layer 230a, and the second liquid crystal cell 210b are stacked along the z-axis direction in this order from the side closest to the light source.

[0110] The first liquid crystal cell 210a and the second liquid crystal cell 210b have the same basic configuration and function. Therefore, when the first liquid crystal cell 210a and the second liquid crystal cell 210b are not distinguished, the liquid crystal cell will be described as the liquid crystal cell 210, and when the first liquid crystal cell 210a and the second liquid crystal cell 210b are distinguished, the liquid crystal cell will be described as the first liquid crystal cell 210a and the second liquid crystal cell 210b.

[0111] The adhesive layer 230a bonds and fixes the first liquid crystal cell 210a and the second liquid crystal cell 210b. The adhesive layer 230a can be formed from the same material as the adhesive layer 130a.

[0112] The light source 30 and the control device 40 have the same configuration as the lighting device 100. The control device 40 controls the liquid crystal optical element 20 and the light source 30. Specifically, the control device 40 supplies a control signal (electric potential) capable of controlling the light distribution direction and orientation angle of light to the first liquid crystal cell 210 a and the second liquid crystal cell 210 b of the liquid crystal optical element 20, and can supply a control signal (electric potential) capable of controlling the lighting and brightness of the light source 30.

[0113] The liquid crystal optical element 20 and the light source 30 are electrically connected to the control device 40. For example, the control device 40 is electrically connected to the liquid crystal optical element 20 and the second liquid crystal cell 210b. The control device 40 is electrically connected via the first flexible wiring board 11a electrically connected to the terminal portion 22a of the first liquid crystal cell 210a and the second flexible wiring board 11b electrically connected to the terminal portion 22b of the second liquid crystal cell 210b.

[0114] Light emitted from the light source 30 to the liquid crystal optical element 20 passes through the first liquid crystal cell 210a, the adhesive layer 230a, and the second liquid crystal cell 210b, and is emitted from the second liquid crystal cell 210b. Although details will be described later, for example, light passing through the liquid crystal optical element 20 is refracted in the x-axis direction or the y-axis direction based on the configuration of each electrode included in the liquid crystal cell 210 and the voltage supplied to each electrode from the control device 40. In other words, the lighting device 200 can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 20, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0115] 2-2. Configuration of the Liquid Crystal Optical Element 20 The configuration of the liquid crystal optical element 20 will be outlined with reference to FIGS. 17 and 18. FIGS. 17 and 18 are schematic cross-sectional views showing a partial cross-sectional structure of the liquid crystal optical element 20. Specifically, FIG. 17 is a schematic cross-sectional view in the zx plane taken along line C1-C2 shown in FIG. 16, and FIG. 18 is a schematic cross-sectional view in the yz plane taken along line D1-D2 shown in FIG. 16. Configurations that are the same as or similar to those in FIG. 16 will be described as necessary. In the following description, the configuration and function of the first liquid crystal cell 210a will be described, and the configuration and function of the second liquid crystal cell 210b will be described as necessary.

[0116] The first liquid crystal cell 210a includes a first substrate 211a, a second substrate 221a, a plurality of first transparent electrodes 281 (e.g., a first transparent electrode 281-1a, a first transparent electrode 281-2a), a plurality of second transparent electrodes 282 (e.g., a second transparent electrode 282-1a, a second transparent electrode 282-2a, a second transparent electrode 282-3a), a plurality of third electrodes 283 (e.g., a third electrode 283-1a, a third electrode 283-2a, a third electrode 283-3a), a fourth transparent electrode 284, a first alignment film 214a, a second alignment film 224a, and a liquid crystal layer 260a.

[0117] The configurations of the first substrate 211a, the second substrate 221a, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the first alignment film 214a, the second alignment film 224a, and the liquid crystal layer 260a are similar to the configurations of the first substrate 111a, the second substrate 121a, the plurality of first transparent electrodes 181, the plurality of second transparent electrodes 182, the first alignment film 114a, the second alignment film 124a, and the liquid crystal layer 160a, respectively. Therefore, the configurations of the first substrate 211a, the second substrate 221a, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the first alignment film 214a, the second alignment film 224a, and the liquid crystal layer 260a will be described as necessary.

[0118] The plurality of third electrodes 283 are disposed on the second substrate 221a. The plurality of third electrodes 283 function as a light-shielding film that blocks light. The fourth transparent electrode 284 is disposed on the plurality of third electrodes 283 and the second substrate 221a so as to cover the plurality of third electrodes 283 and the second substrate 221a and to be in contact with the plurality of third electrodes 283 and the second substrate 221a. The first transparent electrode 281 and the second transparent electrode 282 on the first substrate 211a are disposed so as to face the third electrode 283 and the fourth transparent electrode 284 on the second substrate 221a.

[0119] As with the lighting device 100, the first substrate 211a and the second substrate 221a of the lighting device 200 are bonded together using a sealing material (not shown), and the liquid crystal layer 260a containing the liquid crystal of the lighting device 200 is provided in a space surrounded by the first alignment film 214a, the second alignment film 224a, and the sealing material.

[0120] The plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, and the plurality of third electrodes 283 extend in the y-axis direction. The plurality of third electrodes 283 are arranged at intervals along the x-axis direction.

[0121] The fourth transparent electrode 284 functions as an electrode for forming an electric field in the liquid crystal layer 260 a, similar to the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, and the plurality of third electrodes 283. The plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, and the fourth transparent electrode 284 are made of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0122] The first alignment film 214a is provided with alignment characteristics such that the alignment direction of the liquid crystal molecules on the first substrate 211a side of the first liquid crystal cell 210a is perpendicular to the extension direction of the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282. For example, by making the long axes of the first transparent electrode 281 and the second transparent electrode 282 perpendicular to the x-axis direction, the direction of the alignment treatment, the direction of the alignment treatment coincides with the direction of the electric field when a potential difference is generated between the first transparent electrode 281 and the second transparent electrode 282. As a result, the liquid crystal optical element 10 has good light extraction efficiency.

[0123] In addition, the second alignment film 224a is given alignment characteristics so that the alignment direction of the liquid crystal molecules on the second substrate 221a side of the first liquid crystal cell 210a is parallel to the extension direction of the multiple third electrodes 283.

[0124] 17 and 18, for convenience, the alignment direction of the liquid crystal molecules in the liquid crystal layer 260a is indicated using arrows and symbols with a cross inside a circle. The arrows represent the alignment direction of the liquid crystal molecules aligned parallel to the paper surface, and the symbols with a cross inside a circle represent the alignment direction of the liquid crystal molecules aligned perpendicular to the paper surface. For example, the alignment direction of the liquid crystal molecules on the first substrate 211a side is the x-axis direction, and the alignment direction of the liquid crystal molecules on the second substrate 221a side is the y-axis direction.

[0125] As shown in Figure 17, the liquid crystal molecules in the cross-sectional structure in the x-axis direction of the liquid crystal optical element 20 change their orientation direction from the x-axis direction to the y-axis direction as they move from the first substrate 211a side to the second substrate 221a side, and are oriented so that they are twisted by 90 degrees.

[0126] 18, the liquid crystal molecules in the cross-sectional structure in the x-axis direction of the liquid crystal optical element 20 change their alignment direction from the y-axis direction to the x-axis direction as they move from the first substrate 211a side to the second substrate 221a side, and are aligned so as to be twisted by 90 degrees. Note that Figures 17 and 18 show the state of the liquid crystal optical element 20 when no potential is supplied to the transparent electrodes of the first liquid crystal cell 210a and the second liquid crystal cell 210b.

[0127] The second liquid crystal cell 210b includes a first substrate 211b, a second substrate 221b, a plurality of first transparent electrodes 281 (e.g., a first transparent electrode 281-1b, a first transparent electrode 281-2b), a plurality of second transparent electrodes 282 (e.g., a second transparent electrode 282-1b, a second transparent electrode 282-2b, a second transparent electrode 282-3b), a plurality of third electrodes 283 (e.g., a third electrode 283-1b, a third electrode 283-2b, a third electrode 283-3b), a fourth transparent electrode 284, a first alignment film 214b, a second alignment film 224b, and a liquid crystal layer 260b. The first substrate 211b, the second substrate 221b, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the plurality of third electrodes 283, the fourth transparent electrode 284, the first alignment film 214b, the second alignment film 224b, and the liquid crystal layer 260b have the same configurations and functions as the first substrate 211a, the second substrate 221a, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the plurality of third electrodes 283, the fourth transparent electrode 284, the first alignment film 214a, the second alignment film 224a, and the liquid crystal layer 260a, respectively. Therefore, a description of the second liquid crystal cell 210b will be omitted here.

[0128] In a plan view, the first transparent electrodes 281 provided in the first liquid crystal cell 210a and the second liquid crystal cell 210b are overlapped with each other so that the extending directions (y-axis direction) of the first transparent electrodes 281 are aligned with each other. Similarly, the transparent electrodes with the same name provided in the first liquid crystal cell 210a and the second liquid crystal cell 210b are overlapped with each other so that the extending directions (y-axis direction) of the first transparent electrodes 281 are aligned with each other. That is, the lighting device 200 includes a configuration in which liquid crystal cells (the first liquid crystal cell 210a and the second liquid crystal cell 210b) having the same configuration are overlapped with each other. As shown in FIGS. 17 and 18 , the lower substrates (substrates on the light source side) of the pair of upper and lower substrates constituting the first liquid crystal cell 210a and the second liquid crystal cell 210b are the first substrates 211a and 211b.

[0129] As explained in "1-1. Configuration of the illumination device 200," the first liquid crystal cell 210a and the second liquid crystal cell 210b have the same basic configuration and function. Therefore, when distinguished, the first substrate 211a and the first substrate 211b, the second substrate 221a and the second substrate 221b, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the plurality of third electrodes 283, the fourth transparent electrode 284, the first alignment film 214a and the first alignment film 214b, the second alignment film 224a and the second alignment film 224b, and the liquid crystal layer 260a and the liquid crystal layer 260b will be described using their respective names. When the components contained in the first liquid crystal cell 210a and the second liquid crystal cell 210b described above are not distinguished from one another, the components contained in the first liquid crystal cell 210a and the second liquid crystal cell 210b are described as a first substrate 211, a second substrate 221, a plurality of first transparent electrodes 281, a plurality of second transparent electrodes 282, a plurality of third electrodes 283, a plurality of fourth transparent electrodes 284, a first alignment film 214, a second alignment film 224, and a liquid crystal layer 260.

[0130] <2-3. Arrangement of Transparent Electrodes> An overview of each electrode of the liquid crystal optical element 20 will be described with reference to FIGS. 16 and 19 to 21. FIG. 19 is a schematic plan view showing the arrangement of a plurality of first transparent electrodes 281 and a plurality of second transparent electrodes 282 on the first substrate 211 of the liquid crystal optical element 20. FIG. 20 is a schematic plan view showing the arrangement of a plurality of third electrodes 283 and a fourth transparent electrode 284 on the second substrate 221 of the liquid crystal optical element 20. FIG. 21 is a cross-sectional view showing the cross-sectional structure of a portion of the liquid crystal optical element 20. Note that FIG. 21 corresponds to the cross-sectional structure of the first liquid crystal cell 210a taken along line C1-C2 shown in FIG. 16. Configurations that are the same as or similar to those in FIGS. 16 to 18 will be described as necessary.

[0131] The cross-sectional structure of the first liquid crystal cell 210a is the same as that of the second liquid crystal cell 210b, and the cross-sectional structure of the first liquid crystal cell 210a will be described here, and the cross-sectional structure of the second liquid crystal cell 210b will be described as necessary.

[0132] First, an outline of each electrode of the liquid crystal optical element 20 in a planar view will be described with reference to Figures 16, 19, and 20. As shown in Figure 19, in a planar view, a plurality of first transparent electrodes 281, a plurality of second transparent electrodes 282, a first terminal 219-1, and a second terminal 219-2 are provided on a first substrate 211. In addition, a fifth wiring 216-5, a sixth wiring 216-6, a plurality of first power supply terminals 218-1, a plurality of second power supply terminals 218-2, and a third terminal 219-3 are provided on the first substrate 211.

[0133] The plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 are supplied with a control signal (electric potential) from the control device 40, and have the functions of transmitting, making it difficult to transmit, diffusing, and refracting the light emitted from the light source 30.

[0134] The plurality of first transparent electrodes 281 includes a first transparent electrode 281-1. The plurality of second transparent electrodes 282 includes a second transparent electrode 282-1 and a second transparent electrode 282-2. The major axes of the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 extend in the y-axis direction, and the first transparent electrodes 281 and the second transparent electrodes 282 are alternately arranged along the x-axis direction.

[0135] The electrode width of the first transparent electrode 281 and the electrode width of the second transparent electrode 282 (width in the x-axis direction) are the third width w ３ The inter-electrode distance (electrode spacing) between the first transparent electrode 281 and the second transparent electrode 282 in the x-axis direction is the third inter-electrode distance p ３ In the lighting device 200, the third width w ３ is the third inter-electrode distance p ３ The electrode width of the first transparent electrode 281 and the electrode width of the second transparent electrode 282 may be different.

[0136] The cell gap d is the distance between the third electrodes p ３ For example, the cell gap d of the lighting device 200 has a similar configuration to the cell gap d of the lighting device 100. For example, the cell gap d of the lighting device 200 is 30 μm. When the cell gap d is smaller than the third inter-electrode distance p ３ Based on this smaller (narrower) size, the transverse electric field generated on the first substrate 211a side and the second substrate 112a side affects the liquid crystal molecules located near the center between the first substrate 211a and the second substrate 112a, and the lighting device 200 can bend the incident light 180.

[0137] The plurality of first transparent electrodes 281 are electrically connected to the first wirings 216-1, and the first wirings 216-1 are electrically connected to the first terminals 219-1. The first wirings 216-1 may be formed below the plurality of first transparent electrodes 281 or above the plurality of first transparent electrodes 281. Furthermore, the first wirings 216-1 may be formed in the same layer as the plurality of first transparent electrodes 281. The plurality of second transparent electrodes 282 are electrically connected to the second wirings 216-2, and the second wirings 216-2 are electrically connected to the second terminals 219-2. The second wirings 216-2 may be formed below the plurality of second transparent electrodes 282 or above the plurality of second transparent electrodes 282. Furthermore, the second wirings 216-2 may be formed in the same layer as the plurality of second transparent electrodes 282. For example, the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 of the lighting device 200 are formed in the same layer as the first wiring 216-1 and the second wiring 216-2.

[0138] The fifth wiring 216-5 is electrically connected to the plurality of first power supply terminals 218-1, the sixth wiring 216-6, the plurality of second power supply terminals 218-2, and the third terminal 219-3.

[0139] The first alignment film 214 disposed on the first substrate 211 is aligned in the x-axis direction (the direction indicated by the hollow arrow in FIG. 19 ). In this case, the long axes of the liquid crystal molecules constituting the liquid crystal layer 260 on the first substrate 211 side are aligned along the x-axis direction. That is, the alignment direction of the first alignment film 214 (x-axis direction) and the extension direction (y-axis direction) of the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 are perpendicular to each other.

[0140] 20 , in a plan view, a plurality of third electrodes 283, a fourth transparent electrode 284, a plurality of third power supply terminals 218-3, and a plurality of fourth power supply terminals 218-4 are provided on a second substrate 221. The plurality of third electrodes 283, the plurality of third power supply terminals 218-3, and the plurality of fourth power supply terminals 218-4 may be formed between the second substrate 221 and the fourth transparent electrode 284, or may be formed on the fourth transparent electrode 284 formed on the second substrate 221. For example, the plurality of third electrodes 283, the fourth transparent electrode 284, the plurality of third power supply terminals 218-3, and the plurality of fourth power supply terminals 218-4 are formed on the second substrate 221, and are formed between the second substrate 221 and the fourth transparent electrode 284. Furthermore, the plurality of third electrodes 283, the fourth transparent electrode 284, the plurality of third power supply terminals 218-3, and the plurality of fourth power supply terminals 218-4 are covered with and in contact with the fourth transparent electrode 284. The plurality of third electrodes 283 and the plurality of third power supply terminals 218-3 are electrically connected to the fourth transparent electrode 284.

[0141] The plurality of third electrodes 283 and the fourth transparent electrodes 284, like the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282, are supplied with a control signal (electric potential) from the control device 40, and have the functions of transmitting, making it difficult to transmit, diffusing, and refracting the light emitted from the light source 30.

[0142] The plurality of third electrodes 283 includes a third electrode 283-1, a third electrode 283-2, and a third electrode 283-3. The major axis of each of the plurality of third electrodes 283 extends in the y-axis direction, and the third electrodes 283 are spaced apart along the x-axis direction. The width of the third electrodes 283 is a fourth width w ４ The inter-electrode distance (electrode spacing) between adjacent third electrodes 283 in the x-axis direction is equal to the fourth inter-electrode distance p ４ In the lighting device 200, the fourth width w ４ is the third width w ３ The third electrode distance p ３ is the fourth inter-electrode distance p ４ The cell gap d is narrower than the fourth width w ４ Narrower.

[0143] In the liquid crystal cell 210, the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 face the plurality of third electrodes 283 and the fourth transparent electrodes 284 via the liquid crystal layer 260a. The extending direction (y-axis direction) of the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282 is parallel to the extending direction (y-axis direction) of the plurality of third electrodes 283.

[0144] When the first substrate 211 is bonded to the second substrate 221, each of the plurality of first power supply terminals 218-1 is electrically connected to the corresponding third power supply terminal 218-3, and each of the plurality of second power supply terminals 218-2 is electrically connected to the corresponding fourth power supply terminal 218-4. As a result, the first wiring 216-1 and the sixth wiring 216-6 are electrically connected to the plurality of third electrodes 283 and the fourth transparent electrode 284. For example, the first power supply terminal 218-1 and the third power supply terminal 218-3, and the second power supply terminal 218-2 and the fourth power supply terminal 218-4 can be electrically connected using silver paste or conductive particles. Note that the conductive particles include particles coated with a metal.

[0145] 16, 19, and 20, the length of the second substrate 221 along the x-axis direction is shorter than the length of the first substrate 211 along the x-axis direction. The first terminal 219-1, the second terminal 219-2, and the third terminal 219-3 are provided on the terminal portion 22 on the first substrate 211. As a result, when the first substrate 211 is bonded to the second substrate 221, the first terminal 219-1, the second terminal 219-2, and the third terminal 219-3 are exposed and not covered by the second substrate 221.

[0146] Therefore, in the first liquid crystal cell 210a, the terminal portion 22a can be easily attached to the first flexible wiring board 11a and easily electrically connected. As a result, the plurality of first transparent electrodes 281 receive a control signal (electric potential) from the control device 40 (see FIG. 16 ) via the first flexible wiring board 11a, the terminal portion 22a, the first terminal 219-1, and the first wiring 216-1. The plurality of second transparent electrodes 282 receive a control signal (electric potential) from the control device 40 via the first flexible wiring board 11a, the terminal portion 22a, the second terminal 219-2, and the second wiring 216-2. The plurality of third electrodes 283 and the fourth transparent electrode 284 receive a control signal (electric potential) from the control device 40 via the first flexible wiring substrate 11a, the terminal portion 22a, the third terminal 219-3, the fifth wiring 216-5, the plurality of first power supply terminals 218-1, the sixth wiring 216-6, the plurality of second power supply terminals 218-2, the plurality of third power supply terminals 218-3, and the plurality of fourth power supply terminals 218-4. Similar to the first liquid crystal cell 210a, the terminal portion 22b of the second liquid crystal cell 210b can be easily attached to the second flexible wiring substrate 11b and easily electrically connected. Similarly to the first liquid crystal cell 210a, each electrode in the second liquid crystal cell 210b also receives a control signal (electric potential) from the control device 40.

[0147] A metal material can be used as a material for forming the first wiring 216-1, the second wiring 216-2, the fifth wiring 216-5, the sixth wiring 216-6, the plurality of first power supply terminals 218-1, the plurality of third power supply terminals 218-3, the plurality of second power supply terminals 218-2, the plurality of fourth power supply terminals 218-4, the first terminal 219-1, the second terminal 219-2, the third terminal 219-3, and the plurality of third electrodes 283. The metal material is, for example, aluminum or molybdenum.

[0148] Next, with reference to FIG. 21, the cross-sectional structure of a portion of the liquid crystal optical element 20 will be described.

[0149] The first transparent electrode 281-1a is sandwiched between two adjacent second transparent electrodes 282-1a and 282-2a. The first transparent electrode 281-1a overlaps, along the z-axis direction, the end of the third electrode 283-2a on the third electrode 283-1a side and the space between the third electrodes 283-1a and 283-2a.

[0150] The space between the first transparent electrode 281-1a and the second transparent electrode 282-1a overlaps with the space between the third electrode 283-1a and the third electrode 283-2a along the z-axis direction.

[0151] The second transparent electrode 282-1a overlaps, along the z-axis direction, the end of the third electrode 283-1a on the third electrode 283-2a side and the space between the third electrodes 283-1a and 283-2a.

[0152] The first transparent electrode 281-2a is configured in the same manner as the first transparent electrode 281-1a, and the second transparent electrodes 282-2a and 282-3a are configured in the same manner as the second transparent electrode 282-1a.

[0153] The third electrode 283-2a is sandwiched between two adjacent third electrodes 283-1a and a third transparent electrode 183-3a. A fourth transparent electrode 284 is disposed between the third electrodes 283-1a and 283-2a, between the third electrodes 283-2a and 283-3a, on the upper surface of the third electrode 283-1a, the upper surface of the third electrode 283-2a, and the upper surface of the third electrode 283-3a.

[0154] The first liquid crystal cell 210a includes a plurality of first regions ZN1 and a plurality of second regions ZN2, which are alternately arranged along the x-axis direction.

[0155] The first region ZN1 is adjacent to the second region ZN2. The first region ZN1 includes, along the z-axis direction, a region where the space between the first transparent electrode 281-1a and the second transparent electrode 282-1a overlaps with the space between the third electrodes 283-1a and the third electrodes 283-2a, a region where the space between the third electrodes 283-1a and the third electrodes 283-2a overlaps with the end of the first transparent electrode 281-1a on the second transparent electrode 282-1a side, and a region where the space between the third electrodes 283-1a and the third electrodes 283-2a overlaps with the end of the second transparent electrode 282-1a on the first transparent electrode 281-1a side. That is, the first region ZN1 includes, along the z-axis direction, a region where the space between the first transparent electrode 281 and the second transparent electrode 282 overlaps with the space between adjacent third electrodes 283, a region where the space between adjacent third electrodes 283 overlaps with the end of the first transparent electrode 281, and a region where the space between adjacent third electrodes 283 overlaps with the end of the second transparent electrode 282.

[0156] The second region ZN2 includes, along the z-axis direction, a region where the space between the first transparent electrode 281-1a and the second transparent electrode 282-2a overlaps with the opposing third electrode 283-2a, a region where the end of the first transparent electrode 281-1a on the second transparent electrode 282-2a side overlaps with the end of the opposing third electrode 283-2a on the third electrode 283-1a side, and a region where the end of the second transparent electrode 282-2a on the first transparent electrode 281-1a side overlaps with the end of the opposing third electrode 283-2a on the third electrode 283-1a side. That is, the second region ZN2 includes, along the z-axis direction, a region where the space between the first transparent electrode 281 and the second transparent electrode 282 overlaps with the opposing third electrode 283, a region where the end of the first transparent electrode 281 overlaps with the opposing third electrode 283, and a region where the end of the second transparent electrode 282 overlaps with the opposing third electrode 283.

[0157] Width OV ５ is the width in the z-axis direction where the end of the first transparent electrode 281-1a on the second transparent electrode 282-2a side overlaps with the end of the third electrode 283-2a on the third electrode 283-1a side. ５ is the width at which the end of the first transparent electrode 281-2a on the second transparent electrode 282-3a side overlaps with the end of the third electrode 283-3a on the third electrode 283-2a side along the z-axis direction. ５ is the width of the overlap of the first transparent electrode 281 with the edge of the third electrode 283 along the z-axis direction.

[0158] Width OV ６ is the width at which the end of the second transparent electrode 282-2a on the first transparent electrode 281-1a side overlaps with the end of the third electrode 283-2a on the third electrode 283-3a side along the z-axis direction. ６ is the width at which the end of the second transparent electrode 282-3a overlaps with the end of the third electrode 283-3a along the z-axis direction. ６ is the width by which the edge of the second transparent electrode 282 overlaps with the edge of the third electrode 283.

[0159] The cell gap d may be the distance between the surface where the liquid crystal layer 260 a and the first alignment film 214 a contact each other and the surface where the liquid crystal layer 260 a and the first alignment film 214 a contact each other, or may be the distance between the first substrate 211 a and the second substrate 221 a. For example, the cell gap d of the lighting device 200 is the distance between the surface where the liquid crystal layer 260 a and the first alignment film 214 a contact each other and the surface where the liquid crystal layer 260 a and the first alignment film 214 a contact each other.

[0160] <2-4. Control of light distribution by liquid crystal optical element 20> Light distribution using the liquid crystal optical element 20 will be described with reference to Figs. 22 to 25. Fig. 22 is a cross-sectional view for explaining light distribution using the liquid crystal optical element 20. Fig. 23 is a diagram showing the relationship between each region in the first liquid crystal cell 210a and the phase difference. Figs. 24 and 25 are timing charts showing voltages supplied to each terminal included in the liquid crystal optical element 20. Configurations that are the same as or similar to those in Figs. 1 to 21 will be described as necessary.

[0161] 22 to 25, the liquid crystal optical element 20 will be described in a state where a potential is supplied to each transparent electrode of the first liquid crystal cell 210a. Note that the configuration and function of the second liquid crystal cell 210b are similar to those of the first liquid crystal cell 210a, and therefore will be described as necessary.

[0162] When different control signals (potentials) are supplied from the control device 40 to adjacent first transparent electrodes 281 and second transparent electrodes 282 among the plurality of first transparent electrodes 281 and the plurality of second transparent electrodes 282, a potential difference is generated between the adjacent first transparent electrodes 281 and second transparent electrodes 282. As a result, an electric field (first electric field) is generated between the adjacent first transparent electrodes 281 and second transparent electrodes 282. The same control signal (potential) as that supplied to either the plurality of first transparent electrodes 281 or the plurality of second transparent electrodes 282 from the control device 40 is supplied to the plurality of third electrodes 283 and fourth transparent electrodes 284. For example, the first electric field is called a transverse electric field.

[0163] At this time, a potential difference is generated between either one of the first transparent electrode 281 or the second transparent electrode 282, to which a control signal different from that supplied to the plurality of third electrodes 283 and the fourth transparent electrode 284 is supplied, and the opposing plurality of third electrodes 283 and the fourth transparent electrode 284. As a result, an electric field (third electric field) is generated between either one of the first transparent electrode 281 or the second transparent electrode 282, to which a control signal different from that supplied to the plurality of third electrodes 283 and the fourth transparent electrode 284 is supplied, and the opposing plurality of third electrodes 283 and the fourth transparent electrode 284. Note that the same control signal (potential) is supplied between either one of the first transparent electrode 281 or the second transparent electrode 282, to which the same control signal as that supplied to the plurality of third electrodes 283 and the fourth transparent electrode 284 is supplied, and the opposing plurality of third electrodes 283 and the fourth transparent electrode 284, so that a potential difference is not generated.

[0164] For example, as shown in Figures 22 and 24, a high potential VH(+) is supplied to the plurality of second transparent electrodes 282 (second transparent electrode 282-1a, second transparent electrode 282-2a, and second transparent electrode 282-3a), and a low potential VL(-) is supplied to the plurality of first transparent electrodes 281 (first transparent electrode 281-1a, first transparent electrode 281-2a), the plurality of third electrodes 283 (third electrode 283-1a to third electrode 283-3a), and the fourth transparent electrode 284.

[0165] As a result, a potential difference (VH-VL) is generated between the second transparent electrode 282 and the first transparent electrode 281, generating a transverse electric field. Also, a potential difference (VH-VL) is generated between the second transparent electrode 282 and the plurality of third electrodes 283 and the fourth transparent electrode 284, generating an electric field. Note that no potential difference is generated between the plurality of first transparent electrodes 281 and the plurality of third electrodes 283 and the fourth transparent electrode 284, and therefore no electric field is generated. When an electric field is generated, the orientation state of liquid crystal molecules in the liquid crystal layer 260a, which is affected by the electric field, changes.

[0166] The relationship between each region and the phase difference according to the cross-sectional view shown in Fig. 22 is shown in Fig. 23. For example, the control angle θ in Fig. 22 and Fig. 23 is smaller than 90 degrees.

[0167] 23, the phase difference of light incident on the first region ZN1 gradually increases as the light travels from the first substrate 211a side to the second substrate 221a side. That is, the light incident on the first region ZN1 is bent as the light travels from the first substrate 211a side to the second substrate 221a side, and is optically rotated in the space between the third electrode 283-1a and the third electrode 283-2a, the space between the third electrode 283-2a and the third electrode 283-3a, and the space between the third electrode 283-3a and the adjacent third electrode, before being emitted from the second substrate 221a. For example, based on FIG. 23, light incident between the second transparent electrode 282-1a and the first transparent electrode 281-1a is bent (e.g., bent to the right) from the second transparent electrode 282-1a toward the third electrode 283-2a and rotates its light. Furthermore, the phase difference of light incident on the second region ZN2 gradually decreases as it travels from the first substrate 211a side toward the second substrate 221a side. The second region ZN2 includes a third electrode 283 on the second substrate 221a side. Because the third electrode 283 has a light-blocking function, light incident on the second region ZN2 is not emitted from the second substrate 221a.

[0168] 22 and 23 , by supplying a high potential VH or a low potential VL to each electrode of the lighting device 200, the lighting device 200 can bend light (e.g., incident light 180 (see FIG. 16 )) incident on the incident surface 63 of the first liquid crystal cell 210a at a control angle θ smaller than 90 degrees, rotate the light, and then emit the light from the first liquid crystal cell 210a. The bent light emitted from the first liquid crystal cell 210a passes through the second liquid crystal cell 210b and is emitted from the second liquid crystal cell 210b. For example, the first polarized light 61 incident on the incident surface 63 of the first liquid crystal cell 210a is bent and rotated, and is further rotated and transmitted through the second liquid crystal cell 210b, before being emitted from the liquid crystal optical element 20. Since the second polarized light 62 is rotated 90 degrees from the first polarized light 61, it rotates and passes through the first liquid crystal cell 210a, and is bent and rotated in the same way as the first polarized light 61 in the second liquid crystal cell 210b, and is emitted from the liquid crystal optical element 20.

[0169] Also, for example, as shown in FIG. 25, a low potential VL is supplied to the plurality of second transparent electrodes 282 (second transparent electrode 282-1a, second transparent electrode 282-2a, and second transparent electrode 282-3a), and a high potential VH is supplied to the plurality of first transparent electrodes 281 (first transparent electrode 281-1a, first transparent electrode 281-2a), the plurality of third electrodes 283 (third electrode 283-1a to third electrode 283-3a), and the fourth transparent electrode 284.

[0170] That is, a high potential VH is supplied to the second transparent electrode 282-1a, the second transparent electrode 282-2a, the third electrode 283-1a to the third electrode 283-3a, and the fourth transparent electrode 284, and a low potential VL is supplied to the first transparent electrode 281-1a and the first transparent electrode 281-1b.

[0171] As a result, a potential difference (VH-VL) is generated between the second transparent electrode 282 and the first transparent electrode 281, generating a transverse electric field. Also, a potential difference (VH-VL) is generated between the second transparent electrode 282 and the plurality of third electrodes 283 and the fourth transparent electrode 284, generating an electric field. Note that no potential difference is generated between the plurality of first transparent electrodes 281 and the plurality of third electrodes 283 and the fourth transparent electrode 284, and therefore no electric field is generated. When an electric field is generated, the orientation state of liquid crystal molecules in the liquid crystal layer 260a, which is affected by the electric field, changes.

[0172] The control angle θ when the lighting device 200 is operated using the timing chart shown in Fig. 25 is greater than 90 degrees. That is, the phase difference of the light incident on the first region ZN1 changes as in the second region ZN2 shown in Fig. 23. That is, the light incident on the first region ZN1 is bent as it travels from the first substrate 211a side to the second substrate 221a side, and is optically rotated in the space between the third electrode 283-1a and the third electrode 283-2a, the space between the third electrode 283-2a and the third electrode 283-3a, and the space between the third electrode 283-3a and the adjacent third electrode, and is then emitted from the second substrate 221a. For example, light incident between the second transparent electrode 282-1a and the first transparent electrode 281-1a is bent (for example, bent to the left) so as to travel from the first transparent electrode 281-1a toward the third electrode 283-1a, and is optically rotated. Furthermore, light incident on the second region ZN2 is blocked by the third electrode 283, and therefore the light incident on the second region ZN2 is not emitted from the second substrate 221a.

[0173] 25, a high potential VH or a low potential VL is supplied to each electrode of the lighting device 200, whereby the lighting device 200 can bend and rotate light incident on the incident surface 63 of the first liquid crystal cell 210a (for example, incident light 180 (see FIG. 16)) at a control angle θ greater than 90 degrees, and then emit the light from the first liquid crystal cell 210a. The bent light emitted from the first liquid crystal cell 210a passes through the second liquid crystal cell 210b and is emitted from the second liquid crystal cell 210b.

[0174] As described above, similar to the lighting device 100, the lighting device 200 can supply a potential to each electrode included in the liquid crystal optical element 20, thereby causing light bent at a control angle θ corresponding to the supplied potential to be emitted from the liquid crystal optical element 20. Thus, the lighting device 200 can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 20, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0175] Third Embodiment An outline of the configuration of an illumination device 200A according to a third embodiment will be described with reference to FIGS. 26 and 27 . FIG. 26 is a schematic perspective view showing the configuration of the illumination device 200A. Compared to the illumination device 200, the illumination device 200A has the same alignment treatment of the second alignment film 224a on the second substrate 221 as the alignment treatment of the second alignment film 224a on the second substrate 221 in the illumination device 100. Furthermore, since the alignment treatment of the second alignment film 224 on the second substrate 221 in the illumination device 200A is the same as the alignment treatment of the second alignment film 224 on the second substrate 221 in the illumination device 100, the illumination device 200A includes a wave plate 240 between the first liquid crystal cell 210e and the second liquid crystal cell 210f, similar to the illumination device 100. The remaining configuration of the illumination device 200A is the same as the configuration of the illumination device 100 or the illumination device 200. Therefore, the same configuration as the configuration of the lighting device 100 or the lighting device 200 will be explained as needed. Also, the same or similar configuration as in Figures 1 to 25 will be explained as needed.

[0176] The outline of the configuration of the lighting device 200A will be described with reference to Fig. 26. Fig. 26 is a schematic perspective view showing the configuration of the lighting device 200A.

[0177] 26, the illumination device 200A includes a liquid crystal optical element 20A, a light source 30, and a control device 40. The liquid crystal optical element 20A includes a first liquid crystal cell 210e, an adhesive layer 230-1p, a wave plate 240, an adhesive layer 230-2p, and a second liquid crystal cell 210f. The adhesive layer 230-1p is provided between the first liquid crystal cell 210e and the wave plate 240, and the adhesive layer 230-2p is provided between the wave plate 240 and the second liquid crystal cell 210f. The first liquid crystal cell 210e, the adhesive layer 230-1p, the wave plate 240, the adhesive layer 230-2p, and the second liquid crystal cell 210f are stacked in this order along the z-axis direction, from the side closest to the light source.

[0178] The configuration and function of the wave plate 240 are similar to those of the wave plate 140. The configuration and function of the adhesive layers 230-1p and 230-2p are similar to those of the adhesive layer 130a. The configurations and functions of the light source 30 and the control device 40 are similar to those of the lighting device 100 or 200.

[0179] The configurations and functions of the first liquid crystal cell 230e and the second liquid crystal cell 230f are different from those of the first liquid crystal cell 210a and the second liquid crystal cell 210b in the direction of the alignment treatment of the second alignment film 224 on the second substrate 221. The alignment treatment of the second alignment film 224 on the second substrate 221 is similar to the alignment treatment of the second alignment film 224 on the second substrate 221 in the lighting device 100. Specifically, as shown in FIG. 27 , the second alignment film 224 is aligned in the x-axis direction and in a direction approaching the terminal portion 22. The configurations and functions of the first liquid crystal cell 230e and the second liquid crystal cell 230f, other than the direction of the alignment treatment of the second alignment film 224, are similar to those of the first liquid crystal cell 210a and the second liquid crystal cell 210b.

[0180] 24 and 25 used in the lighting device 200, a high potential VH or a low potential VL is supplied to each electrode of the lighting device 200A, whereby the lighting device 200A can bend and transmit light incident on the incident surface 63 (see FIG. 22) of the first liquid crystal cell 210e at a control angle θ smaller than 90 degrees, rotate the light by 90 degrees by the wave plate 240, transmit the light through the second liquid crystal cell 110f, and emit the light from the liquid crystal optical element 20A (second liquid crystal cell 210f). For example, the first polarized light 61 incident on the incident surface 63 of the first liquid crystal cell 210e is bent and transmitted, rotated by 90 degrees by the wave plate 240, transmitted through the second liquid crystal cell 210f, and emitted from the liquid crystal optical element 20A. Since the second polarized light 62 is rotated 90 degrees from the first polarized light 61, it passes through the first liquid crystal cell 210e, rotates 90 degrees by the wavelength plate 240, is bent and passes through the second liquid crystal cell 210f in the same way as the first polarized light 61, and is emitted from the liquid crystal optical element 20A.

[0181] As described above, similar to the lighting devices 100 and 200, the lighting device 200A can supply a potential to each electrode included in the liquid crystal optical element 20A, thereby causing light to be bent at a control angle θ corresponding to the supplied potential to be emitted from the liquid crystal optical element 20A. Thus, the lighting device 200A can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 20A, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0182] Fourth Embodiment An outline of the configuration of an illumination device 200B according to a fourth embodiment will be described with reference to FIGS. 28 and 29 . FIG. 28 is a schematic perspective view showing the configuration of the illumination device 200B. FIG. 29 is a cross-sectional view showing the cross-sectional structure of a portion of a liquid crystal optical element 20B. Compared to the illumination device 200, the illumination device 200B includes a configuration in which a liquid crystal optical element having the same configuration and function as the liquid crystal optical element 20 is rotated 90 degrees along the z-axis direction and superimposed on the liquid crystal optical element 20. The other configuration of the illumination device 200B is the same as that of the illumination device 200. Therefore, configurations similar to those of the illumination device 200 will be described as necessary. Furthermore, configurations that are the same as or similar to those in FIGS. 1 to 27 will be described as necessary.

[0183] First, the outline of the configuration of the lighting device 200B will be described with reference to FIG.

[0184] 28 , the illumination device 200B includes a liquid crystal optical element 20B, a light source 30, and a control device 40. The liquid crystal optical element 20B includes a first liquid crystal cell 210a, an adhesive layer 230a, a second liquid crystal cell 210b, an adhesive layer 230b, a third liquid crystal cell 210c, an adhesive layer 230c, and a fourth liquid crystal cell 210d. The adhesive layer 230a is provided between the first liquid crystal cell 210a and the second liquid crystal cell 210b, the adhesive layer 230b is provided between the second liquid crystal cell 210b and the third liquid crystal cell 210c, and the adhesive layer 230c is provided between the third liquid crystal cell 210c and the fourth liquid crystal cell 210d. The first liquid crystal cell 210a, adhesive layer 230a, second liquid crystal cell 210b, adhesive layer 230b, third liquid crystal cell 210c, adhesive layer 230c, and fourth liquid crystal cell 210d are stacked along the z-axis direction in this order, starting from the side closest to the light source.

[0185] The first liquid crystal cell 210a, the second liquid crystal cell 210b, the third liquid crystal cell 210c, and the fourth liquid crystal cell 210d have the same basic configuration and function. The configurations and functions of the first liquid crystal cell 210a and the second liquid crystal cell 210b are similar to those of the first liquid crystal cell 210a and the second liquid crystal cell 210b of the lighting device 200, and therefore will be described as necessary.

[0186] The adhesive layers 230a to 230c can be made of the same material as the adhesive layer 130a.

[0187] The light source 30 and the control device 40 have the same configuration as the lighting device 100. The control device 40 controls the liquid crystal optical element 20B and the light source 30. Specifically, the control device 40 supplies control signals (electric potentials) capable of controlling the light distribution direction and orientation angle of light to the first to fourth liquid crystal cells 210a to 210d of the liquid crystal optical element 20B, and can supply control signals (electric potentials) capable of controlling the lighting and brightness of the light source 30.

[0188] The liquid crystal optical element 20B and the light source 30 are electrically connected to the control device 40. For example, the control device 40 is electrically connected via a third flexible wiring board 11c electrically connected to the terminal portion 22c of the first liquid crystal cell 210a, a second flexible wiring board 11b electrically connected to the terminal portion 22b of the second liquid crystal cell 210b, a third flexible wiring board 11c electrically connected to the terminal portion 22c of the third liquid crystal cell 210c, and a fourth flexible wiring board 11d electrically connected to the terminal portion 22d of the fourth liquid crystal cell 210d.

[0189] Light emitted from the light source 30 to the liquid crystal optical element 20B is emitted from the first liquid crystal cell 210a, the adhesive layer 230a, the second liquid crystal cell 210b, the adhesive layer 230b, the third liquid crystal cell 210c, the adhesive layer 230c, and the fourth liquid crystal cell 210d. For example, light passing through the liquid crystal optical element 20B is refracted in the x-axis direction or the y-axis direction based on the configuration of each electrode included in the liquid crystal cell 210 and the voltage supplied to each electrode from the control device 40. In other words, the lighting device 200B can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 20B and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0190] Next, the configuration of the liquid crystal optical element 20B will be outlined with reference to Fig. 29. Specifically, Fig. 29 is a schematic cross-sectional view in the zx plane taken along the line E1-E2 shown in Fig. 28.

[0191] The third liquid crystal cell 210c has the same configuration and function as the first liquid crystal cell 210a, and the fourth liquid crystal cell 210d has the same configuration and function as the second liquid crystal cell 210b. The lighting device 200B has a configuration in which liquid crystal optical elements (third liquid crystal cells 210c and fourth liquid crystal cells 210d having the same structure) having the same configuration as the liquid crystal optical element 10 (first liquid crystal cell 210a and second liquid crystal cell 210b having the same structure) are rotated by 90 degrees and stacked on the liquid crystal optical element 10 described in the lighting device 200.

[0192] The third liquid crystal cell 210c includes a first substrate 211c, a second substrate 221c, a plurality of first transparent electrodes (not shown), a plurality of second transparent electrodes 282 (e.g., second transparent electrode 282-1c), a plurality of third electrodes 283 (e.g., third electrode 283-1c), a fourth transparent electrode 284c, a first alignment film 214c, a second alignment film 224c, and a liquid crystal layer 260c.

[0193] The fourth liquid crystal cell 210d includes a first substrate 211d, a second substrate 221d, a plurality of first transparent electrodes (not shown), a plurality of second transparent electrodes 282 (e.g., second transparent electrode 282-1d), a plurality of third electrodes 283 (e.g., third electrode 283-1d), a fourth transparent electrode 284d, a first alignment film 214d, a second alignment film 224d, and a liquid crystal layer 260d. Each component of the fourth liquid crystal cell 210d is similar to each component of the third liquid crystal cell 210c.

[0194] The configurations of the first substrate 211c, the second substrate 221c, the plurality of first transparent electrodes 281, the plurality of second transparent electrodes 282, the first alignment film 214c, the second alignment film 224c, and the liquid crystal layer 260c are similar to the configurations of the first substrate 111a, the second substrate 121a, the plurality of first transparent electrodes 181, the plurality of second transparent electrodes 182, the first alignment film 114a, the second alignment film 124a, and the liquid crystal layer 160a, respectively. Therefore, detailed descriptions of the third liquid crystal cell 210c and the fourth liquid crystal cell 210d will be omitted.

[0195] The extension direction of the plurality of first transparent electrodes, the plurality of second transparent electrodes 282, and the plurality of third electrodes 283 included in the third liquid crystal cell 210c and the fourth liquid crystal cell 210d is perpendicular to the extension direction of the plurality of first transparent electrodes, the plurality of second transparent electrodes 282, and the plurality of third electrodes 283 included in the first liquid crystal cell 210a and the second liquid crystal cell 210b.

[0196] The direction (x-axis direction) of the alignment treatment of the first substrate 211 of the first liquid crystal cell 210a and the second liquid crystal cell 210b is perpendicular to the direction (y-axis direction) of the alignment treatment of the first substrate 211 of the third liquid crystal cell 210c and the fourth liquid crystal cell 210d. Similar to the first substrate 211, the direction (y-axis direction) of the alignment treatment of the second substrate 221 of the first liquid crystal cell 210a and the second liquid crystal cell 210b is perpendicular to the direction (x-axis direction) of the alignment treatment of the second substrate 221 of the third liquid crystal cell 210c and the fourth liquid crystal cell 210d.

[0197] As a result, for example, the first liquid crystal cell 210a bends the first polarized light 61 parallel to the y-axis direction in the x-axis direction and rotates it, the second liquid crystal cell 210b bends the second polarized light 62 parallel to the x-axis direction in the x-axis direction and rotates it, the third liquid crystal cell 210c bends the first polarized light 61 parallel to the y-axis direction in the y-axis direction and advances it, and the fourth liquid crystal cell 210d bends the second polarized light 62 parallel to the x-axis direction in the y-axis direction and rotates it.

[0198] Therefore, the lighting device 200B can bend light in two directions, the x-axis direction and the y-axis direction.

[0199] Furthermore, similar to the lighting device 200, the lighting device 200B can supply a potential to each electrode included in the liquid crystal optical element 20B, thereby causing light to be bent at a control angle θ corresponding to the supplied potential to be emitted from the liquid crystal optical element 20B. Thus, the lighting device 200B can adjust the light distribution direction and light distribution angle using the liquid crystal optical element 20B, and can irradiate light having various adjusted light distribution directions and light distribution angles.

[0200] The various configurations of the liquid crystal optical element and lighting device exemplified as one embodiment of the present invention can be combined as appropriate as long as they are not mutually inconsistent. Furthermore, the various configurations of the liquid crystal optical element and lighting device exemplified as one embodiment of the present invention can be interchanged as appropriate as long as they are not mutually inconsistent. A liquid crystal optical element and lighting device that a person skilled in the art has appropriately added or deleted components or modified the design, or added or omitted steps or modified conditions based on the liquid crystal optical element and lighting device disclosed in this specification and drawings, is also included in the scope of the present invention as long as it comprises the gist of the present invention.

[0201] Even if there are other effects and advantages different from those brought about by the aspects of the embodiments disclosed in this specification, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention.

[0202] 10: liquid crystal optical element, 11a: first flexible wiring board, 11b: second flexible wiring board, 11c: third flexible wiring board, 11d: fourth flexible wiring board, 12: terminal portion, 12a: terminal portion, 12b: terminal portion, 20: liquid crystal optical element, 20A: liquid crystal optical element, 20B: liquid crystal optical element, 22: terminal portion, 22a: terminal portion, 22b: terminal portion, 22c: terminal portion, 22d: terminal portion, 30: light source, 31: light emitting element, 32: reflector, 33: convex lens, 40: control device, 61: first polarized light, 62: second polarized light, 63: incident surface, 100: lighting device, 110: liquid crystal cell, 110a: first liquid crystal cell, 110b: second liquid crystal cell, 110f: second liquid crystal cell, 111: first substrate, 111a: first substrate, 111b: first substrate, 112a: second substrate, 114: first alignment film, 114a: first alignment film, 114b: first alignment film, 116-1: first wiring, 116-2: second wiring, 116-3: third wiring, 116-4: fourth wiring, 116-5: fifth wiring, 116-6: sixth wiring, 118-1: first power supply terminal, 118-2: second power supply terminal, 118-3: third power supply terminal, 118-4: fourth 4 power supply terminal, 119-1: first terminal, 119-2: second terminal, 119-3: third terminal, 119-4: fourth terminal, 121: second substrate, 121a: second substrate, 121b: second substrate, 124: second alignment film, 124a: second alignment film, 124b: second alignment film, 130a: adhesive layer, 130b: adhesive layer, 140: wave plate, 160: liquid crystal layer, 160a: liquid crystal layer, 160b: liquid crystal layer, 180: incident light, 181: first transparent electrode, 181-1: first transparent electrode, 181-1a: first transparent electrode, 181-1b: first transparent electrode, 182: second transparent electrode, 182-1: second transparent electrode, 182-1a: second transparent electrode, 182-1b: second transparent electrode, 182-2: second transparent electrode, 182-2a: second transparent electrode, 182-2b: second transparent electrode, 182-3a: second transparent electrode, 183: third transparent electrode, 183-1: third transparent electrode, 183-1a: third transparent electrode, 183-1b: third transparent electrode, 183-2: third transparent electrode, 183-2a: third transparent electrode, 183-2b: third transparent electrode, 183-3a: third transparent electrode, 184: fourth transparent electrode, 184-1: fourth transparent electrode,184-1a: fourth transparent electrode, 184-1b: fourth transparent electrode, 184-2: fourth transparent electrode, 184-2a: fourth transparent electrode, 184-2b: fourth transparent electrode, 200: lighting device, 200A: lighting device, 200B: lighting device, 210: liquid crystal cell, 210a: first liquid crystal cell, 210b: second liquid crystal cell, 210c: third liquid crystal cell, 210d: fourth liquid crystal cell, 210e: first liquid crystal cell, 210f: second liquid crystal cell, 211: first substrate, 211a: first substrate, 211b: first substrate, 211c: first substrate, 211d: first substrate, 214 : first alignment film, 214a: first alignment film, 214b: first alignment film, 214c: first alignment film, 214d: first alignment film, 216-1: first wiring, 216-2: second wiring, 216-5: fifth wiring, 216-6: sixth wiring, 218-1: first power supply terminal, 218-2: second power supply terminal, 218-3: third power supply terminal, 218-4: fourth power supply terminal, 219-1: first terminal, 219-2: second terminal, 219-3: third terminal, 221: second substrate, 221a: second substrate, 221b: second substrate, 221c: second substrate, 221d: second substrate plate, 224: second alignment film, 224a: second alignment film, 224b: second alignment film, 224c: second alignment film, 224d: second alignment film, 230-1p: adhesive layer, 230-2p: adhesive layer, 230a: adhesive layer, 230b: adhesive layer, 230c: adhesive layer, 230e: first liquid crystal cell, 230f: second liquid crystal cell, 240: wave plate, 260: liquid crystal layer, 260a: liquid crystal layer, 260b: liquid crystal layer, 260c: liquid crystal layer, 260d: liquid crystal layer, 281: first transparent electrode, 281-1: first transparent electrode, 281-1a: first transparent electrode, 281-1b: first transparent electrode, 281 -2a: first transparent electrode, 281-2b: first transparent electrode, 282: second transparent electrode, 282-1: second transparent electrode, 282-1a: second transparent electrode, 282-1b: second transparent electrode, 282-1c: second transparent electrode, 282-1d: second transparent electrode, 282-2: second transparent electrode, 282-2a: second transparent electrode, 282-2b: second transparent electrode, 282-3a: second transparent electrode, 282-3b: second transparent electrode, 283: third electrode, 283-1: third electrode, 283-1a: third electrode, 283-1b: third electrode, 283-1c: third electrode,283-1d: third electrode, 283-2: third electrode, 283-2a: third electrode, 283-2b: third electrode, 283-3: third electrode, 283-3a: third electrode, 283-3b: third electrode, 284: fourth transparent electrode, 284c: fourth transparent electrode, 284d: fourth transparent electrode,

Claims

1. A liquid crystal display device comprising a first liquid crystal cell and a second liquid crystal cell overlapping the first liquid crystal cell, each of the first liquid crystal cell and the second liquid crystal cell comprising a first substrate, a first electrode and a second electrode disposed on the first substrate, a second substrate disposed opposite to the first substrate, a third electrode and a fourth electrode disposed on the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, the first electrode and the second electrode being alternately disposed parallel to a first direction and extending in a second direction intersecting the first direction, the third electrode and the fourth electrode being alternately disposed parallel to the first direction and extending in the second direction, the first electrode overlapping a first end of the third electrode, a space between the third electrode and the fourth electrode, and a first end of the fourth electrode in a third direction intersecting the first direction and the second direction, the fourth electrode overlaps, in the third direction, a space between the first electrode and the second electrode and a first end of the second electrode.

2. The liquid crystal optical element according to claim 1, wherein each of the first liquid crystal cell and the second liquid crystal cell further comprises: a first alignment film disposed on the first electrode and the second electrode; and a second alignment film disposed on the third electrode and the fourth electrode and facing the first alignment film.

3. The liquid crystal optical element according to claim 2, wherein the direction of the alignment treatment of the first alignment film and the direction of the alignment treatment of the second alignment film are parallel to the first direction.

4. The liquid crystal optical element according to claim 1, further comprising a wave plate disposed between the first liquid crystal cell and the second liquid crystal cell.

5. The liquid crystal optical element according to claim 1, wherein the width of the first electrode is the same as the width of the second electrode and is narrower than the width of the third electrode.

6. The liquid crystal optical element according to claim 1, wherein the space between the first electrode and the second electrode is larger than the space between the third electrode and the fourth electrode.

7. The liquid crystal optical element according to claim 2, wherein a cell gap between the first alignment film and the second alignment film along the third direction is narrower than a width of the first electrode.

8. The liquid crystal optical element according to claim 1, wherein the first electrode, the second electrode, the third electrode, and the fourth electrode include a transparent material.

9. A lighting device comprising a control device electrically connected to the liquid crystal optical element according to claim 1, the control device supplying control signals to the first electrode, the second electrode, the third electrode and the fourth electrode.

10. The lighting device according to claim 9, wherein the control device supplies a first control signal to the first electrode and the fourth electrode, and supplies a second control signal having a polarity different from that of the first control signal to the second electrode and the third electrode.

11. A liquid crystal display device comprising a first liquid crystal cell and a second liquid crystal cell overlapping the first liquid crystal cell, each of the first liquid crystal cell and the second liquid crystal cell comprising a first substrate, a first electrode and a second electrode disposed on the first substrate, a second substrate disposed opposite to the first substrate, a third electrode and a fourth electrode disposed on the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, the first electrode and the second electrode being alternately disposed parallel to a first direction and extending in a second direction intersecting the first direction, the third electrode being disposed parallel to the first direction and extending in the second direction, the fourth electrode being disposed on the second substrate so as to cover the third electrode, the first electrode overlapping a first end of the third electrode and a space between the third electrodes in a third direction intersecting the first direction and the second direction, A liquid crystal optical element, wherein the third electrode overlaps, in the third direction, a space between the first electrode and the second electrode and a first end of the second electrode, and the space between the third electrodes overlaps with a space between the first electrode and a second electrode different from the second electrode.

12. The liquid crystal optical element according to claim 11, wherein each of the first liquid crystal cell and the second liquid crystal cell further comprises: a first alignment film disposed on the first electrode and the second electrode; and a second alignment film disposed on the third electrode and the fourth electrode and facing the first alignment film.

13. The liquid crystal optical element according to claim 12, wherein the direction of the alignment treatment of the first alignment film is parallel to the first direction, and the direction of the alignment treatment of the second alignment film is parallel to the second direction.

14. The liquid crystal optical element according to claim 12, wherein the space between the third electrodes is wider than the space between the first electrodes and the second electrodes, and the cell gap between the first alignment film and the second alignment film along the third direction is narrower than the width of the third electrodes.

15. The liquid crystal optical element according to claim 11, wherein the third electrode contains a metal material and blocks light passing through the first substrate.

16. The liquid crystal optical element according to claim 12, wherein the direction of the alignment treatment of the first alignment film and the direction of the alignment treatment of the second alignment film are parallel to the first direction.

17. The liquid crystal optical element according to claim 16, further comprising a wave plate disposed between the first liquid crystal cell and the second liquid crystal cell.

18. The liquid crystal optical element according to claim 11, further comprising: a third liquid crystal cell overlapping the second liquid crystal cell; and a fourth liquid crystal cell overlapping the third liquid crystal cell, wherein the third liquid crystal cell and the fourth liquid crystal cell overlap the second liquid crystal cell by being rotated 90 degrees about an axis parallel to the third direction, and each of the third liquid crystal cell and the fourth liquid crystal cell has the first substrate, the first electrode, the second electrode, the second substrate, the third electrode, the fourth electrode, and the liquid crystal layer.

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