Patent Publication Number: US-2023147664-A1

Title: Liquid crystal device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2020-179556, filed Oct. 27, 2020, the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a liquid crystal device. 
     BACKGROUND 
     Recently, a light control device using a liquid crystal cell has been proposed. Such a light control device mainly focuses or diverges a polarized light component. In one example, a liquid crystal lens comprising a plurality of ring strip electrodes has been proposed. In another example, a liquid crystal lens comprising transparent electrodes disposed in a plurality of divided areas spreading like a fan has been proposed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view showing a liquid crystal device  1  according to one embodiment. 
         FIG.  2    is an exploded perspective view showing the liquid crystal device  1  shown in  FIG.  1   . 
         FIG.  3    is a perspective view showing a first liquid crystal cell  10 , a second liquid crystal cell  20 , a third liquid crystal cell  30  and a fourth liquid crystal cell  40 . 
         FIG.  4    is a plan view showing a configuration example of a first substrate S 11  shown in  FIG.  3   . 
         FIG.  5    is a plan view showing a configuration example of a second substrate S 21  shown in  FIG.  3   . 
         FIG.  6    is a cross-sectional view showing a configuration example of the first liquid crystal cell  10 . 
         FIG.  7    is an illustration schematically showing the first liquid crystal cell  10  in an off state (OFF) where no electric field is formed in a liquid crystal layer LC 1 . 
         FIG.  8    is an illustration schematically showing the first liquid crystal cell  10  in an on state (ON) where an electric field is formed in the liquid crystal layer LC 1 . 
         FIG.  9    is a plan view for explaining an example of the extension directions of first electrodes E 11  and second electrodes E 21  in the first liquid crystal cell  10 . 
         FIG.  10    is a plan view for explaining an example of the extension directions of first electrodes E 12  and second electrodes E 22  in the second liquid crystal cell  20 . 
         FIG.  11    is a plan view for explaining an example of the extension directions of first electrodes E 13  and second electrodes E 23  in the third liquid crystal cell  30 . 
         FIG.  12    is a plan view for explaining an example of the extension directions of first electrodes E 14  and second electrodes E 24  in the fourth liquid crystal cell  40 . 
     
    
    
     DETAILED DESCRIPTION 
     In general, according to one embodiment, there is provided a liquid crystal device comprising a first liquid crystal cell and a second liquid crystal cell bonded to the first liquid crystal cell. The first liquid crystal cell and the second liquid crystal cell each comprise a first substrate comprising a plurality of first electrodes formed in a strip shape, a second substrate comprising a plurality of second electrodes formed in a strip shape, and a liquid crystal layer held between the first substrate and the second substrate. An angle of intersection of the first electrodes and the second electrodes is less than 90° in each of the first liquid crystal cell and the second liquid crystal cell. 
     According to another embodiment, there is provided a liquid crystal device comprising a first liquid crystal cell, a second liquid crystal cell bonded to the first liquid crystal cell, a third liquid crystal cell bonded to the second liquid crystal cell, and a fourth liquid crystal cell bonded to the third liquid crystal cell. The first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell and the fourth liquid crystal cell each comprise a first substrate comprising a plurality of first electrodes formed in a strip shape, a second substrate comprising a plurality of second electrodes formed in a strip shape, and a liquid crystal layer held between the first substrate and the second substrate. An angle of intersection of the first electrodes and the second electrodes is less than 90° in each of the first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell and the fourth liquid crystal cell. 
     Embodiments will be described hereinafter with reference to the accompanying drawings. The disclosure is merely an example, and proper changes in keeping with the spirit of the invention, which are easily conceivable by a person of ordinary skill in the art, come within the scope of the invention as a matter of course. In addition, in some cases, in order to make the description clearer, the widths, thicknesses, shapes and the like, of the respective parts are illustrated schematically in the drawings, rather than as an accurate representation of what is implemented. However, such schematic illustration is merely exemplary, and in no way restricts the interpretation of the invention. In addition, in the specification and drawings, constituent elements which function in the same or a similar manner to those described in connection with preceding drawings are denoted by the same reference numbers, and detailed descriptions thereof which are considered redundant are omitted where appropriate. 
     In the drawings, an X-axis, a Y-axis and a Z-axis which are orthogonal to each other are shown as needed for easier understanding. A direction along the X-axis is referred to as a first direction X, a direction along the Y-axis is referred to as a second direction Y, and a direction along the Z-axis is referred to as a third direction Z. A plane defined by the X-axis and the Y-axis is referred to as an X-Y plane, and viewing the X-Y plane is referred to as planar view. 
       FIG.  1    is a perspective view showing a liquid crystal device  1  according to the present embodiment. 
     The liquid crystal device  1  comprises a first liquid crystal cell  10 , a second liquid crystal cell  20 , a third liquid crystal cell  30 , a fourth liquid crystal cell  40 , a first flexible wiring board F 1 , a second flexible wiring board F 2 , a third flexible wiring board F 3 , a fourth flexible wiring board F 4  and a circuit board  50 . The liquid crystal device  1  according to the present embodiment comprises two or more liquid crystal cells, and is not limited to a configuration comprising four liquid crystal cells as in the example shown in  FIG.  1   . 
     The first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  are stacked in this order in the third direction Z. 
     The first flexible wiring board F 1  electrically connects the first liquid crystal cell  10  and the circuit board  50 . The second flexible wiring board F 2  electrically connects the second liquid crystal cell  20  and the circuit board  50 . The third flexible wiring board F 3  electrically connects the third liquid crystal cell  30  and the circuit board  50 . The fourth flexible wiring board F 4  electrically connects the fourth liquid crystal cell  40  and the circuit board  50 . 
     The first flexible wiring board F 1 , the second flexible wiring board F 2 , the third flexible wiring board F 3  and the fourth flexible wiring board F 4  are bent along edges of the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40 , respectively, and are also bent along an edge  50 E of the circuit board  50 . The circuit board  50  is disposed to be opposed to the fourth liquid crystal cell  40  in the third direction Z. 
     An area for disposing a light source portion LS shown by a dotted line is secured between the circuit board  50  and the fourth liquid crystal cell  40 . The light source portion LS comprises at least a light source, and comprises an optical element such as a lens between the light source and the fourth liquid crystal cell  40  as needed. 
     Light emitted from the light source portion LS is, for example, natural light. The light emitted from the light source portion LS is transmitted through the fourth liquid crystal cell  40 , the third liquid crystal cell  30 , the second liquid crystal cell  20  and the first liquid crystal cell  10  in order. As will be described later, the fourth liquid crystal cell  40 , the third liquid crystal cell  30 , the second liquid crystal cell  20  and the first liquid crystal cell  10  are configured to diffuse part of the polarized light components of incident light. As described above, it is possible to provide an illumination device capable of changing a light diffusion direction by combining the liquid crystal device  1  and the light source portion LS. 
       FIG.  2    is an exploded perspective view showing the liquid crystal device  1  shown in  FIG.  1   . In  FIG.  2   , the illustrations of the first flexible wiring board F 1 , the second flexible wiring board F 2 , the third flexible wiring board F 3  and the fourth flexible wiring board F 4  are omitted. 
     The first liquid crystal cell  10  comprises a first substrate S 11  and a second substrate S 21 . The first substrate S 11  has an extension portion EX 1  which extends more outward than the second substrate S 21  along the first direction X, and an extension portion EY 1  which extends more outward than the second substrate S 21  along the second direction Y. 
     The second liquid crystal cell  20  comprises a first substrate S 12  and a second substrate S 22 . The first substrate S 12  has an extension portion EX 2  which extends more outward than the second substrate S 22  along the first direction X, and an extension portion EY 2  which extends more outward than the second substrate S 22  along the second direction Y. The extension portion EX 2  overlaps the extension portion EX 1  and the extension portion EY 2  overlaps the extension portion EY 1  in the third direction Z. 
     The third liquid crystal cell  30  comprises a first substrate S 13  and a second substrate S 23 . The first substrate S 13  has an extension portion EX 3  which extends more outward than the second substrate S 23  along the first direction X, and an extension portion EY 3  which extends more outward than the second substrate S 23  along the second direction Y. The extension portion EY 3  overlaps the extension portion EY 2  in the third direction Z. The extension portion EX 3  does not overlap the extension portion EX 2  but is located on the opposite side to the extension portion EX 2 . 
     The fourth liquid crystal cell  40  comprises a first substrate S 14  and a second substrate S 24 . The first substrate S 14  has an extension portion EX 4  which extends more outward than the second substrate S 24  along the first direction X, and an extension portion EY 4  which extends more outward than the second substrate S 24  along the second direction Y. The extension portion EX 4  overlaps the extension portion EX 3  and the extension portion EY 4  overlaps the extension portion EY 3  in the third direction Z. 
     A transparent adhesive layer A 12  is disposed between the first liquid crystal cell  10  and the second liquid crystal cell  20 . The transparent adhesive layer A 12  bonds the first substrate S 11  of the first liquid crystal cell  10  and the second substrate S 22  of the second liquid crystal cell  20 . 
     A transparent adhesive layer S 23  is disposed between the second liquid crystal cell  20  and the third liquid crystal cell  30 . The transparent adhesive layer A 23  bonds the first substrate S 12  of the second liquid crystal cell  20  and the second substrate S 23  of the third liquid crystal cell  30 . 
     A transparent adhesive layer A 34  is disposed between the third liquid crystal cell  30  and the fourth liquid crystal cell  40 . The transparent adhesive layer A 34  bonds the first substrate S 13  of the third liquid crystal cell  30  and the second substrate S 24  of the fourth liquid crystal cell  40 . 
     Next, the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  will be described. 
       FIG.  3    is a perspective view showing the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40 . 
     The first liquid crystal cell  10  comprises the first substrate S 11 , the second substrate S 21  and a liquid crystal layer LC 1 . The liquid crystal layer LC 1  is held between the first substrate S 11  and the second substrate S 21 . The first substrate S 11  comprises a plurality of first electrodes E 11  formed in a strip shape. The first electrodes E 11  extend along the first direction X, and are arranged at intervals along the 0 second direction Y. The second substrate S 21  comprises a plurality of second electrodes E 21  formed in a strip shape. The second electrodes E 21  extend along the second direction Y, and are arranged at intervals along the first direction X. That is, the first electrodes E 11  and the second electrodes E 21  intersect each other. As will be described later, the angle of intersection of the first electrodes E 11  and the second electrodes E 21  is less than 90° in planar view. 
     The second liquid crystal cell  20  comprises the first substrate S 12  comprising a plurality of first electrodes E 12 , the second substrate S 22  comprising a plurality of second electrodes E 22 , and a liquid crystal layer LC 2 . The liquid crystal layer LC 2  is held between the first substrate S 12  and the second substrate S 22 . The first electrodes E 12  extend along the first direction X, and are arranged at intervals along the second direction Y. The second electrodes E 22  extend along the second direction Y, and are arranged at intervals along the first direction X. The angle of intersection of the first electrodes E 12  and the second electrodes E 22  is less than 90° in planar view. 
     The third liquid crystal cell  30  comprises the first substrate S 13  comprising a plurality of first electrodes E 13 , the second substrate S 23  comprising a plurality of second electrodes E 23 , and a liquid crystal layer LC 3 . The liquid crystal layer LC 3  is held between the first substrate S 13  and the second substrate S 23 . The first electrodes E 13  extend along the second direction Y, and are arranged at intervals along the first direction X. The second electrodes E 23  extend along the first direction X, and are arranged at intervals along the second direction Y. The angle of intersection of the first electrodes E 13  and the second electrodes E 23  is less than 90° in planar view. 
     The fourth liquid crystal cell  40  comprises the first substrate S 14  comprising a plurality of first electrodes E 14 , the second substrate S 24  comprising a plurality of second electrodes E 24 , and a liquid crystal layer LC 4 . The liquid crystal layer LC 4  is held between the first substrate S 14  and the second substrate S 24 . The first electrodes E 14  extend along the second direction Y, and are arranged at intervals along the first direction X. The second electrodes E 24  extend along the first direction X, and are arranged at intervals along the second direction Y. The angle of intersection of the first electrodes E 14  and the second electrodes E 24  is less than 90° in planar view. 
     The first electrodes E 11  of the first liquid crystal cell  10  and the first electrodes E 14  of the fourth liquid crystal cell  40  are orthogonal to each other in planar view. The first electrodes E 12  of the second liquid crystal cell  20  and the first electrodes E 13  of the third liquid crystal cell  30  are orthogonal to each other in planar view. The first electrodes E 11  of the first liquid crystal cell  10  and the first electrodes E 12  of the second liquid crystal cell  20  intersect each other at an angle of less than 90° in planar view. The first electrodes E 13  of the third liquid crystal cell  30  and the first electrodes E 14  of the fourth liquid crystal cell  40  intersect each other at an angle of less than 90° in planar view. 
     The first substrate S 11  of the first liquid crystal cell  10 , the first substrate S 12  of the second liquid crystal cell  20 , the first substrate S 13  of the third liquid crystal cell  30  and the first substrate S 14  of the fourth liquid crystal cell  40  are formed in a square shape and have an equal size. That is, the first substrates S 11  to S 14  have an equal length LX along the first direction X and have an equal length LY along the second direction Y. In addition, the length LX is equal to the length LY (LX=LY). 
     Therefore, when the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  are bonded together, as shown in  FIG.  1   , edges thereof along the first direction X overlap each other, and edges thereof along the second direction Y overlap each other. 
     The first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  have substantially the same configuration, but the first liquid crystal cell  10  will be described more specifically below as a typical example. 
     The first electrodes E 11  include a plurality of first strip electrodes E 11 A and a plurality of second strip electrodes  11 B. The first strip electrodes E 11 A are electrically connected to each other, and are configured to be subjected to the same voltage (first voltage). The second strip electrodes E 11 B are electrically connected to each other, and are configured to be subjected to the same voltage (second voltage). The voltage applied to the second strip electrodes E 11 B is controlled to be different from the voltage applied to the first strip electrodes E 11 A. These first strip electrodes E 11 A and second strip electrodes E 11 B are alternately arranged along the second direction Y. 
     The second electrodes E 21  include a plurality of third strip electrodes E 21 A and a plurality of fourth strip electrodes E 21 B. The third strip electrodes E 21 A are electrically connected to each other, and are configured to be subjected to the same voltage (third voltage). The fourth strip electrodes E 21 B are electrically connected to each other, and are configured to be subjected to the same voltage (fourth voltage). The voltage applied to the fourth strip electrodes E 21 B is controlled to be different from the voltage applied to the third strip electrodes E 21 A. These third strip electrodes E 21 A and fourth strip electrodes E 21 B are alternately arranged along the first direction X. 
       FIG.  4    is a plan view showing a configuration example of the first substrate S 11  shown in  FIG.  3   . It should be noted that, although the first substrates S 12  to S 14  shown in  FIG.  3    have the same configuration as the first substrate S 11  shown in  FIG.  4   , the extension directions of the first electrodes thereof will be described later. 
     The first substrate S 11  comprises the first electrodes E 11  including the first strip electrodes E 11 A and the second strip electrodes E 11 B, and a plurality of power supply lines PL 11  to PL 14 . The first strip electrodes E 11 A are electrically connected to the power supply line PL 12 . The second strip electrodes E 11 B are electrically connected to the power supply line PL 13 . 
     The power supply line PL 11  has a power supply terminal PT 11  located on one end side and a connection terminal T 11  located on the other end side. The power supply line PL 14  has a power supply terminal PT 14  located on one end side and a connection terminal T 14  located on the other end side. Between the connection terminal T 11  and the connection terminal T 14 , the power supply line PL 12  has a connection terminal T 12 , and the power supply line PL 13  has a connection terminal T 13 . These connection terminals T 11  to T 14  constitute a connection portion connected to the first flexible board F 1  shown in  FIG.  1   . 
       FIG.  5    is a plan view showing a configuration example of the second substrate S 21  shown in  FIG.  3   . It should be noted that, although the second substrates S 22  to S 24  shown in  FIG.  3    have the same configuration as the second substrate S 21  shown in  FIG.  5   , the extension directions of the second electrodes thereof will be described later. 
     The second substrate S 21  comprises the second electrodes E 21  including the third strip electrodes E 21 A and the fourth strip electrodes E 21 B, and a plurality of power supply lines PL 21  and PL 24 . The third strip electrodes E 21 A are electrically connected to the power supply line PL 21 . The fourth strip electrodes E 21 B are electrically connected to the power supply line PL 24 . 
     The power supply line PL 21  has a power supply terminal PT 21  located on one end side. The power supply line PL 24  has a power supply terminal PT 24  located on one end side. When the second substrate S 21  shown in  FIG.  5    is disposed to be opposed to the first substrate S 11  shown in  FIG.  4   , the power supply terminal PT 21  is opposed to the power supply terminal PT 11  of the first substrate S 11 , and the power supply terminal PT 24  is opposed to the power supply terminal PT 14  of the first substrate S 11 . 
       FIG.  6    is a cross-sectional view showing a configuration example of the first liquid crystal cell  10 . Although the first liquid crystal cell  10  is described here, the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  have the same cross-sectional structure, and descriptions thereof are omitted. 
     The first liquid crystal cell  10  has an effective area AA which can scatter incident light. The first substrate S 11  and the second substrate S 21  are bonded together by a sealant SE outside the effective area AA. The liquid crystal layer LC 1  is sealed by the sealant SE. 
     The first substrate S 11  comprises an insulating substrate  11  and an alignment film AL 1  in addition to the first electrodes E 11  and the power supply lines PL 11  to PL 14 . The first electrodes E 11  and the power supply lines PL 11  to PL 14  are disposed on the insulating substrate  11  and are covered with the alignment film AL 1 . 
     The power supply terminal PT 11  integrated with the power supply line PL 11  is drawn to the outside of the sealant SE. The power supply terminal PT 14  integrated with the power supply line PL 14  is drawn to the outside of the sealant SE. The power supply terminals PT 11  and PT 14  are exposed from the alignment film AL 1 . 
     The second substrate S 21  comprises an insulating substrate  21  and an alignment film AL 2  in addition to the second electrodes E 21  and the power supply lines PL 21  and PL 24 . The second electrodes E 21  and the power supply lines PL 21  and PL 24  are disposed on the insulating substrate  21 , and are covered with the alignment film AL 2 . Although only one second electrode E 21  orthogonal to the first electrodes E 11  is illustrated here, as described with reference to  FIG.  5   , the second substrate S 21  comprises the second electrodes E 21  including the third strip electrodes E 21 A and the fourth strip electrodes E 21 B between the insulating substrate  21  and the alignment film AL 2 . 
     The power supply terminal PT 21  integrated with the power supply line PL 21  is drawn to the outside of the sealant SE. The power supply terminal PT 21  is located directly above the power supply terminal PT 11 . The power supply terminal PT 24  integrated with the power supply line PL 24  is drawn to the outside of the sealant SE. The power supply terminal PT 24  is located directly above the power supply terminal PT 14 . The power supply terminals PT 21  and PT 24  are exposed from the alignment film AL 2 . 
     A conductive material CD 1  is disposed between the power supply terminal PT 11  and the power supply terminal PT 21 , and electrically connects these two. A conductive material CD 2  is disposed between the power supply terminal PT 14  and the power supply terminal PT 24 , and electrically connects these two. 
     The insulating substrates  11  and  21  are, for example, transparent substrates such as glass substrates or resin substrates. The first electrodes E 11  and the second electrodes E 21  are transparent electrodes formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The power supply lines PL 11  to PL 14  and the power supply lines PL 21  and PL 24  are formed of a metal material such as aluminum, titanium, molybdenum or tungsten. It should be noted that the power supply lines PL 11  to PL 14  and the power supply lines PL 21  and PL 24  may be formed of the same material as the transparent electrode. The alignment films AL 1  and AL 2  are horizontal alignment films having an alignment regulating force substantially parallel to the X-Y plane. 
     Next, an optical effect in the first liquid crystal cell  10  will be described with reference to  FIGS.  7  and  8   . Only the configuration necessary for explanation is illustrated in  FIGS.  7  and  8   . 
       FIG.  7    is an illustration schematically showing the first liquid crystal cell  10  in an off state (OFF) where no electric field is formed in the liquid crystal layer LC 1 . 
     In the liquid crystal layer LC 1  in the off state, liquid crystal molecules LM 1  are in an initial alignment state. In this off state, the liquid crystal layer LC 1  has substantially uniform refractive index distribution. Therefore, a first polarized light component POL 1  which is incident light to the first liquid crystal cell  10  is transmitted through the liquid crystal layer LC 1  almost without being refracted (or scattered). The first polarized light component POL 1  here corresponds to, for example, p-polarized light of natural light. In the present specification, s-polarized light orthogonal to p-polarized light may be referred to as a second polarized light component POL 2 . 
       FIG.  8    is an illustration schematically showing the first liquid crystal cell  10  in an on state (ON) where an electric field is formed in the liquid crystal layer LC 1 . 
     For example, when the liquid crystal layer LC 1  has a positive dielectric anisotropy, in the on state where an electric field is formed in the liquid crystal layer LC 1 , the liquid crystal molecules LM 1  are aligned such that major axes thereof are along the electric field. Therefore, as shown in  FIG.  8   , an area where the liquid crystal molecules LM 1  are maintained in the initial alignment state, an area where the liquid crystal molecules LM 1  stand substantially vertically to the substrate, an area where the liquid crystal molecules LM 1  stand obliquely to the substrate, and the like are formed in the liquid crystal layer LC 1 . 
     The liquid crystal molecules LM 1  have a refractive index anisotropy Δn. Therefore, the liquid crystal layer LC 1  in the on state has refractive index distribution or retardation distribution according to the alignment state of the liquid crystal molecules LM 1 . The retardation here is represented as Δn·d where d is the thickness of the liquid crystal layer LC 1 . 
     In this on state, when the first polarized light component POL 1  is transmitted through the liquid crystal layer LC 1 , the first polarized light component POL 1  is scattered by the effect of the refractive index distribution of the liquid crystal layer LC 1 . 
     In a configuration where the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  are stacked, for example, the first liquid crystal cell  10  and the fourth liquid crystal cell  40  mainly scatter the first polarized light component (p-polarized light) POL 1  of natural light, and the second liquid crystal cell  20  and the third liquid crystal cell  30  mainly scatter the second polarized light component (s-polarized light) POL 2  of natural light. 
     Incidentally, if white light enters a liquid crystal layer where refractive index distribution is formed, the degree of scattering varies according to wavelength. Therefore, a part of scattered white light may be colored. 
     In the present embodiment, the refractive index distribution formed in the liquid crystal layer LC 1  of the first liquid crystal cell  10  and the refractive index distribution formed in the liquid crystal layer LC 4  of the fourth liquid crystal cell  40  are therefore configured to be different from each other. Accordingly, the degree of scattering of the first polarized light component POL 1  in the first liquid crystal cell  10  and the degree of scattering of the first polarized light component POL 1  in the fourth liquid crystal cell  40  are different from each other, and the coloring of the first polarized light component POL 1  is suppressed. 
     Similarly, the refractive index distribution formed in the liquid crystal layer LC 2  of the second liquid crystal cell  20  and the refractive index distribution formed in the liquid crystal layer LC 3  of the third liquid crystal cell  30  are configured to be different from each other. Accordingly, the degree of scattering of the second polarized light component POL 2  in the second liquid crystal cell  20  and the degree of scattering of the second polarized light component POL 2  in the third liquid crystal cell  30  are different from each other, and the coloring of the second polarized light component POL 2  is suppressed. 
     Next, the extension direction of the first electrodes and the extension direction of the second electrodes in each of the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  will be described. In the following description, a common reference direction is set. The reference direction here may be any direction in the X-Y plane, but is, for example, a direction parallel to the first direction X. In addition, all angles with respect to the reference direction are angles in the counterclockwise direction in the X-Y plane. 
       FIG.  9    is a plan view for explaining an example of the extension directions of the first electrodes E 11  and the second electrodes E 21  in the first liquid crystal cell  10 . 
     An angle θ 11  between the reference direction and the extension direction of the first electrodes E 11  is an acute angle, and an angle θ 21  between the reference direction and the extension direction of the second electrodes E 21  is an obtuse angle. When the first substrate S 11  and the second substrate S 21  are disposed to be opposed to each other, the first electrodes E 11  and the second electrodes E 21  are not orthogonal to each other in planar view. That is, the angle of intersection of the first electrodes E 11  and the second electrodes E 21  is less than 90°. 
     In one example, the angle θ 11  is 3°, and the angle  821  is 91°. That is, the angle of intersection of the first electrodes E 11  and the second electrodes E 21  is 88°. 
       FIG.  10    is a plan view for explaining an example of the extension directions of the first electrodes E 12  and the second electrodes E 22  in the second liquid crystal cell  20 . 
     An angle θ 12  between the reference direction and the extension direction of the first electrodes E 12  is an obtuse angle, and an angle θ 22  between the reference direction and the extension direction of the second electrodes E 22  is an acute angle. That is, the angle  812  is different from the angle θ 11  shown in  FIG.  9   , and the angle θ 22  is different from the angle θ 21  shown in  FIG.  9   . When the first substrate S 12  and the second substrate S 22  are disposed to be opposed to each other, the first electrodes E 12  and the second electrodes E 22  are not orthogonal to each other in planar view. That is, the angle of intersection of the first electrodes E 12  and the second electrodes E 22  is less than 90°. 
     In one example, the angle θ 12  is 179°, and the angle θ 22  is 87°. That is, the angle of intersection of the first electrodes E 12  and the second electrodes E 22  is 88°. As described above, the angle of intersection of the first electrodes E 12  and the second electrodes E 22  is equal to the angle of intersection of the first electrodes E 11  and the second electrodes E 21  shown in  FIG.  9   . 
     In addition, the first electrodes E 11  in the first liquid crystal cell  10  and the first electrodes E 12  in the second liquid crystal cell  20  are non-parallel to each other, and intersect each other at an angle of less than 90°. In one example, the angle of intersection of the first electrodes E 11  and the first electrodes E 12  is 4°. 
     Furthermore, the second electrodes E 21  and the second electrodes E 22  are non-parallel to each other, and intersect each other at an angle of less than 90°. In one example, the angle of intersection of the second electrodes E 21  and the second electrodes E 22  is 4°. 
     In short, when the first liquid crystal cell  10  and the second liquid crystal cell  20  are bonded together, the extension directions of the first electrodes E 11 , the second electrodes E 21 , the first electrodes E 12  and the second electrodes E 22  do not match each other (that is, non-parallel to each other). Since there are no perfectly overlapping electrodes as described above, moire can be suppressed. From the perspective of suppressing moire, the angle of intersection of the first electrodes and the second electrodes is preferably less than or equal to 88°. 
       FIG.  11    is a plan view for explaining an example of the extension directions of the first electrodes E 13  and the second electrodes E 23  in the third liquid crystal cell  30 . 
     An angle θ 13  between the reference direction and the extension direction of the first electrodes E 13  is an acute angle, and an angle θ 23  between the reference direction and the extension direction of the second electrodes E 23  is an obtuse angle. That is, the angle θ 13  is different from the above angles θ 11  and θ 12 , and the angle θ 23  is different from the above angles θ 21  and θ 22 . When the first substrate S 13  and the second substrate S 23  are disposed to be opposed to each other, the first electrodes E 13  and the second electrodes E 23  are not orthogonal to each other in planar view. That is, the angle of intersection of the first electrodes E 13  and the second electrodes E 23  is less than 90°, and is preferably less than or equal to 88°. 
     In one example, the angle θ 13  is 89°, and the angle θ 23  is 177°. That is, the angle of intersection of the first electrodes E 13  and the second electrodes E 23  is 88°. As described above, the angle of intersection of the first electrodes E 13  and the second electrodes E 23  is equal to the angle of intersection of the first electrodes E 11  and the second electrodes E 21  shown in  FIG.  9   . 
     In addition, the extension direction of the first electrodes E 13  is orthogonal to the extension direction of the first electrodes E 12  shown in  FIG.  10   . That is, when the first substrate S 12  shown in  FIG.  10    is rotated 90 degrees clockwise in the X-Y plane, the extension direction of the first electrodes E 12  matches the extension direction of the first electrodes E 13 . Similarly, the extension direction of the second electrodes E 23  is orthogonal to the extension direction of the second electrodes E 22  shown in  FIG.  10   . That is, when the second substrate S 22  shown in  FIG.  10    is rotated 90 degrees clockwise in the X-Y plane, the extension direction of the second electrodes E 22  matches the extension direction of the second electrodes E 23 . 
     In short, the second liquid crystal cell  20  and the third liquid crystal cell  30  are 90 degrees rotationally symmetrical, and the second liquid crystal cell  20  can be used as the third liquid crystal cell  30  when rotated 90 degrees clockwise in the X-Y plane. Therefore, the cost can be reduced as compared with when the second liquid crystal cell  20  and the third liquid crystal cell  30  are prepared separately. 
     In addition, also when the first liquid crystal cell  10 , the second liquid crystal cell  20  and the third liquid crystal cell  30  are bonded together, there are no perfectly overlapping electrodes, and therefore moire can be suppressed. 
       FIG.  12    is a plan view for explaining an example of the extension directions of the first electrodes E 14  and the second electrodes E 24  in the fourth liquid crystal cell  40 . 
     An angle θ 14  between the reference direction and the extension direction of the first electrodes E 14  is an obtuse angle, and an angle θ 24  between the reference direction and the extension direction of the second electrodes E 24  is an acute angle. That is, the angle θ 14  is different from the above angles θ 11  to θ 13 , and the angle θ 24  is different from the above angles θ 21  to θ 23 . When the first substrate S 14  and the second substrate S 24  are disposed to be opposed to each other, the first electrodes E 14  and the second electrodes E 24  are not orthogonal to each other in planar view. That is, the angle of intersection of the first electrodes E 14  and the second electrodes E 24  is less than 90°, and is preferably less than or equal to 88°. 
     In short, in each of the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40 , the angle of intersection of the first electrodes and the second electrodes is less than 90°, is equal, and is less than or equal to 88°. 
     In one example, the angle θ 14  is 93°, and the angle θ 24  is 1°. That is, the angle of intersection of the first electrodes E 14  and the second electrodes E 24  is 88°. As described above, the angle of intersection of the first electrodes E 14  and the second electrodes E 24  is equal to the angle of intersection of the first electrodes E 11  and the second electrodes E 21  shown in  FIG.  9   . 
     In addition, the first electrodes E 13  in the third liquid crystal cell  30  and the first electrodes E 14  in the fourth liquid crystal cell  40  are non-parallel to each other, and intersect each other at an angle of less than 90°. In one example, the angle of intersection of the first electrodes E 13  and the first electrodes E 14  is 4°. 
     Furthermore, the second electrodes E 23  and the second electrodes E 24  are non-parallel to each other, and intersect each other at an angle of less than 90°. In one example, the angle of intersection of the second electrodes E 23  and the second electrodes E 24  is 4°. 
     Furthermore, the extension direction of the first electrodes E 14  is orthogonal to the extension direction of the first electrodes E 11  shown in  FIG.  9   . That is, when the first substrate S 11  shown in  FIG.  9    is rotated 90 degrees clockwise in the X-Y plane, the extension direction of the first electrodes E 11  matches the extension direction of the first electrodes E 14 . Similarly, the extension direction of the second electrodes E 24  is orthogonal to the extension direction of the second electrodes E 21  shown in  FIG.  9   . That is, when the second substrate S 21  shown in  FIG.  9    is rotated 90 degrees clockwise in the X-Y plane, the extension direction of the second electrodes E 21  matches the extension direction of the second electrodes E 24 . 
     In short, the first liquid crystal cell  10  and the fourth liquid crystal cell  40  are 90 degrees rotationally symmetrical, and the first liquid crystal cell  10  can be used as the fourth liquid crystal cell  40  when rotated 90 degrees clockwise in the X-Y plane Therefore, the cost can be reduced as compared with when the first liquid crystal cell  10  and the fourth liquid crystal cell  40  are prepared separately. 
     In addition, also when the first liquid crystal cell  10 , the second liquid crystal cell  20 , the third liquid crystal cell  30  and the fourth liquid crystal cell  40  are bonded together, there are no perfectly overlapping electrodes, and therefore moire can be suppressed. 
     As described above, according to the present embodiment, a liquid crystal device capable of suppressing moire can be provided. 
     The present invention is not limited to the embodiments described above but the constituent elements of the invention can be modified in various manners without departing from the spirit and scope of the invention. Various aspects of the invention can also be extracted from any appropriate combination of a plurality of constituent elements disclosed in the embodiments. Some constituent elements may be deleted in all of the constituent elements disclosed in the embodiments. The constituent elements described in different embodiments may be combined arbitrarily.