Patent Publication Number: US-2022236617-A1

Title: Light ray direction control element and display device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Japanese Patent Application No. 2021-11600, filed on Jan. 28, 2021, the entire disclosure of which is incorporated by reference herein. 
     FIELD 
     The present disclosure relates generally to a light ray direction control element and a display device. 
     BACKGROUND 
     Light ray direction control elements that control the direction of transmitted light are known. For example, Japanese Patent No. 4899503 describes an optical element that is arranged on a front face side of a liquid crystal display element and that controls the direction of light rays that are emitted from a surface emitting light source and that pass through the liquid crystal display element. The optical element of Japanese Patent No. 4899503 includes a pair of transparent substrates that include transparent electrode films, and a composite material layer disposed between the pair of transparent substrates. The composite material layer is formed from a UV curable polymer material and a liquid crystal material dispersed in the UV curable polymer material. The composite material layer includes first regions that have optical transparency, and second regions adjacent to the first regions. In the first regions, the polymer material is cured in a state in which the liquid crystal particles are aligned with the direction that the transparent substrates face. In the second regions, the alignment state of the liquid crystal material is electrically switched between a light transmitting alignment state and a light-scattering alignment state. 
     In Japanese Patent No. 4899503, the viewing angle mode of the optical element is selectively switched by switching the alignment state of the liquid crystal material. Specifically, by setting the liquid crystal material to the light transmitting alignment state, the viewing angle mode is switched to a first viewing angle mode in which the light from the liquid crystal element is emitted at a first angle. Additionally, by setting the liquid crystal material to the light-scattering alignment state, the viewing angle mode is switched to a second viewing angle mode in which the light from the liquid crystal element is emitted at a second angle smaller than the first angle. The optical element of Japanese Patent No. 4899503 can emit light in two types of angle distributions. However, depending on the usage situation, there is a need for an optical element that can emit light in multiple types of angle distributions. 
     SUMMARY 
     A light ray direction control element according to a first aspect includes: 
     a first light transmitting substrate; 
     a second light transmitting substrate facing the first light transmitting substrate; 
     a first light transmitting region that is provided on a first main surface of the first light transmitting substrate and that extends from the first light transmitting substrate toward the second light transmitting substrate; 
     a second light transmitting region that is provided on a first main surface of the second light transmitting substrate that faces the first main surface of the first light transmitting substrate, that extends from the second light transmitting substrate toward the first light transmitting substrate, and that is continuous with the first light transmitting region; 
     a plurality of first light absorbing regions that is positioned among the first light transmitting region and that extends from the first light transmitting substrate toward the second light transmitting substrate; 
     a plurality of second light absorbing regions that is positioned among the second light transmitting region, that extends from the second light transmitting substrate toward the first light transmitting substrate, and that is continuous with the first light absorbing regions; 
     a light transmitting dispersion medium that is enclosed in the first light absorbing regions and the second light absorbing regions; and 
     charged electrophoretic particles that are dispersed in the light transmitting dispersion medium and that have a dispersion state that changes according to voltage that is applied, wherein when viewing a cross-section perpendicular to the first main surface of the first light transmitting substrate and the first main surface of the second light transmitting substrate, a shape or an angle of inclination, with respect to the first main surface of the first light transmitting substrate, of the first light transmitting region and the second light transmitting region differs. 
     A display device according to a second aspect includes: 
     the light ray direction control element described above; and 
     a display panel, wherein the light ray direction control element is disposed on a display surface of the display panel. 
     A display device according to a third aspect includes: 
     the light ray direction control element described above; 
     a transmissive liquid crystal display panel; and 
     a back light that is disposed on a side of the transmissive liquid crystal display panel opposite a display surface, and that supplies light to the transmissive liquid crystal display panel, wherein the light ray direction control element is disposed between the transmissive liquid crystal display panel and the back light. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of this disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of this application can be obtained when the following detailed description is considered in conjunction with the following drawings, in which: 
         FIG. 1  is a schematic drawing illustrating a light ray direction control element according to Embodiment 1; 
         FIG. 2  is a cross-sectional view illustrating a light ray direction controller according to Embodiment 1; 
         FIG. 3  is a schematic drawing illustrating a display device according to Embodiment 1; 
         FIG. 4  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 1; 
         FIG. 5  is a schematic drawing illustrating a light-blocking mode according to Embodiment 1 
         FIG. 6  is a schematic drawing illustrating a first diagonal narrow field mode according to Embodiment 1; 
         FIG. 7  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 1, in a plane parallel to an XZ plane; 
         FIG. 8  is a schematic drawing illustrating a first perpendicular narrow field mode according to Embodiment 1; 
         FIG. 9  is a schematic drawing illustrating a first wide field mode according to Embodiment 1; 
         FIG. 10  is a schematic drawing illustrating a second wide field mode according to Embodiment 1; 
         FIG. 11  is a flowchart illustrating a manufacturing method for the light ray direction control element according to Embodiment 1; 
         FIG. 12  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 2; 
         FIG. 13  is a cross-sectional view illustrating a light ray direction controller according to Embodiment 2; 
         FIG. 14  is a schematic drawing illustrating a third diagonal narrow field mode according to Embodiment 2; 
         FIG. 15  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 2, in a plane parallel to an XZ plane; 
         FIG. 16  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 3; 
         FIG. 17  is a schematic drawing illustrating a second perpendicular narrow field mode according to Embodiment 3; 
         FIG. 18  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 3, in a plane parallel to a YZ plane; 
         FIG. 19  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 4; 
         FIG. 20  is a cross-sectional view illustrating a light ray direction controller according to Embodiment 4; 
         FIG. 21  is a schematic drawing illustrating a third perpendicular narrow field mode according to Embodiment 4; 
         FIG. 22  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 4, in a plane parallel to an XZ plane; 
         FIG. 23  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 5; 
         FIG. 24  is a schematic drawing illustrating a sixth perpendicular narrow field mode according to Embodiment 5; 
         FIG. 25  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 5, in a plane parallel to a YZ plane; 
         FIG. 26  is a perspective view illustrating first light transmitting regions, first light absorbing regions, second light transmitting regions, and second light absorbing regions according to Embodiment 6; 
         FIG. 27  is a schematic drawing illustrating a ninth perpendicular narrow field mode according to Embodiment 6; 
         FIG. 28  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 6, in a plane parallel to an XZ plane; 
         FIG. 29  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 6, in a plane parallel to a YZ plane; 
         FIG. 30  is a schematic drawing illustrating a tenth perpendicular narrow field mode according to Embodiment 6; 
         FIG. 31  is a schematic drawing illustrating the tenth perpendicular narrow field mode according to Embodiment 6; 
         FIG. 32  is a plan view illustrating first light transmitting regions, first light absorbing regions, and second light transmitting regions according to Embodiment 7; 
         FIG. 33  is a side view illustrating the first light transmitting regions, the first light absorbing regions, the second light transmitting regions, and second light absorbing regions according to Embodiment 7; 
         FIG. 34  is a schematic drawing illustrating a twelfth perpendicular narrow field mode according to Embodiment 7; 
         FIG. 35  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 7, in a plane parallel to an XZ plane; 
         FIG. 36  is a drawing illustrating an angle distribution of emitted light of the light ray direction control element according to Embodiment 7, in a plane parallel to a YZ plane; 
         FIG. 37  is a schematic drawing illustrating a fourteenth perpendicular narrow field mode according to Embodiment 7; 
         FIG. 38  is a cross-sectional view illustrating a light ray direction controller according to Embodiment 8; 
         FIG. 39  is a schematic drawing illustrating a fifth diagonal narrow field mode according to Embodiment 8; 
         FIG. 40  is a schematic drawing illustrating a fifteenth perpendicular narrow field mode according to Embodiment 8; 
         FIG. 41  is a schematic drawing illustrating a fifteenth wide field mode according to Embodiment 8; 
         FIG. 42  is a cross-sectional view illustrating a light ray direction controller according to a modified example; and 
         FIG. 43  is a schematic drawing illustrating a display device according to a modified example. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, a light ray direction control element and a display device according to embodiments are described while referencing the drawings. 
     Embodiment 1 
     A light ray direction control element  200  according to the present embodiment is described while referencing  FIGS. 1 to 11 . As illustrated in  FIG. 1 , the light ray direction control element  200  includes a light ray direction controller  100  and a voltage controller  110 . The light ray direction controller  100  controls the angle distribution of transmitting light (that is, the emitted light of the light ray direction controller  100 ). As illustrated in  FIG. 2 , the light ray direction controller  100  includes a first light transmitting substrate  10 , a second light transmitting substrate  20 , first light transmitting regions  32 , first light absorbing regions  34 , second light transmitting regions  42 , and second light absorbing regions  44 . A light transmitting dispersion medium  52  and electrophoretic particles  54  are enclosed in the first light absorbing regions  34  and the second light absorbing regions  44 . The voltage controller  110  controls voltage applied to the electrophoretic particles  54 . Note that, in the present description, to facilitate comprehension, for the light ray direction controller  100  of  FIG. 1 , the right direction (the right direction on paper) is referred to as the “+X direction”, the up direction (the up direction on paper) is referred to as the “+Z direction”, and the direction perpendicular to the +X direction and the +Z direction (the depth direction on paper) is referred to as the “+Y direction.” Additionally, the +X direction, the −X direction, the +Y direction, and the −Y direction may also be referred to respectively as the left direction, the right direction, the up direction, and the down direction. 
     As illustrated in  FIG. 3 , the light ray direction control element  200  and a display panel  210  constitute a display device  300 . The display device  300  is mounted in a smartphone, a laptop computer, a vehicle, an information display, or the like. The display panel  210  displays text, images, and the like. The display panel  210  is implemented as a liquid crystal display panel, an organic electro-luminescence (EL) display panel, or the like. 
     The light ray direction control element  200  controls the angle distribution of light that exits from the display panel  210  and transmits through the light ray direction controller  100 . The light ray direction controller  100  of the light ray direction control element  200  is disposed on a display surface of the display panel  210 . 
     Returning to  FIG. 2 , the first light transmitting substrate  10  of the light ray direction controller  100  transmits visible light. In one example, the first light transmitting substrate  10  is implemented as a flat glass substrate. The first light transmitting substrate  10  includes a first light transmitting electrode  12  on a first main surface  10   a . In the present embodiment, the first light transmitting electrode  12  is formed on the entire first main surface  10   a . The first light transmitting electrode  12  is formed from indium tin oxide (ITO) Additionally, a non-illustrated insulation layer is provided on the first light transmitting electrode  12 . In one example, the insulation layer is formed from silicon oxide (SiO 2 ). 
     As with the first light transmitting substrate  10 , the second light transmitting substrate  20  of the light ray direction controller  100  transmits visible light. In one example, the second light transmitting substrate  20  is implemented as a flat glass substrate. The second light transmitting substrate  20  includes a second light transmitting electrode  22  on a first main surface  20   a . The second light transmitting electrode  22  is formed on the entire first main surface  20   a . The second light transmitting electrode  22  is formed from ITO. Additionally, an insulation layer is provided on the second light transmitting electrode  22 . 
     The second light transmitting substrate  20  faces the first light transmitting substrate  10 . In the present embodiment, the first main surface  10   a  of the first light transmitting substrate  10  and the first main surface  20   a  of the second light transmitting substrate  20  face each other. 
     The first light transmitting regions  32  of the light ray direction controller  100  are regions that transmit visible light. In one example, the first light transmitting regions  32  are light transmitting layers formed from light transmitting resin. The first light transmitting regions  32  are provided on the first main surface  10   a  of the first light transmitting substrate  10 . In the present embodiment, a plurality of first light transmitting regions  32  is arranged in the X direction at a predetermined spacing. The first light transmitting regions  32  have a rectangular parallelepiped shape and, as illustrated in  FIG. 4 , extend in the Y direction. Additionally, as illustrated in  FIG. 2 , the first light transmitting regions  32  extend from the first light transmitting substrate  10  toward the second light transmitting substrate  20 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and are continuous with the second light transmitting regions  42 . 
     As illustrated in  FIGS. 2 and 4 , the first light absorbing regions  34  of the light ray direction controller  100  are regions between adjacent first light transmitting regions  32 . As with the first light transmitting regions  32 , the first light absorbing regions  34  extend from the first light transmitting substrate  10  toward the second light transmitting substrate  20 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . Details of the first light absorbing regions  34  are described later. 
     As with the first light transmitting regions  32 , the second light transmitting regions  42  of the light ray direction controller  100  are regions that transmit visible light. In one example, the second light transmitting regions  42  are light transmitting layers formed from light transmitting resin. The second light transmitting regions  42  are provided on the first main surface  20   a  of the second light transmitting substrate  20 . In the present embodiment, a plurality of second light transmitting regions  42  is arranged in the X direction at the same spacing as the first light transmitting regions  32 . The second light transmitting regions  42  have an oblique quadrangular prism shape and, as illustrated in  FIG. 4 , extend in the Y direction. Additionally, the second light transmitting regions  42  extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , and are continuous with the first light transmitting regions  32 . As illustrated in  FIG. 2 , when viewing a cross-section (the XZ plane) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10  and the first main surface  20   a  of the second light transmitting substrate  20 , the second light transmitting regions  42  are inclined at an angle θ to the +X direction side with respect to the direction (the +Z direction) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . In the present embodiment, the angle θ satisfies tan θ≥D1/H2, where H2 is a height in the Z direction of the second light transmitting regions  42 , and D1 is a width in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42 . 
     The second light transmitting regions  42  are inclined with respect to the direction perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and the first light transmitting regions  32  extend perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . Accordingly, when viewing a cross-section (the XZ plane) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10  and the first main surface  20   a  of the second light transmitting substrate  20 , as illustrated in  FIG. 2 , the angles of inclination, with respect to the first main surface  10   a  of the first light transmitting substrate  10 , of the first light transmitting regions  32  and the second light transmitting regions  42  differ. Note that, in one example, a ratio of a sum H of a height H1 in the Z direction of the first light transmitting regions  32  and the height H2 in the Z direction of the second light transmitting regions  42  to the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  is from 4:1 to 3:1. 
     As illustrated in  FIGS. 2 and 4 , the second light absorbing regions  44  of the light ray direction controller  100  are regions between adjacent second light transmitting regions  42 . When viewing a cross-section on the XZ plane, the second light transmitting regions  42  are inclined the angle θ to the +X direction side with respect to the +Z direction and, as such, the second light absorbing regions  44  are also inclined the angle θ to the +X direction side with respect to the +Z direction. As with the second light transmitting regions  42 , the second light absorbing regions  44  extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , and are continuous with the first light absorbing regions  34 . Details of the second light absorbing regions  44  are described later. 
     The light transmitting dispersion medium  52  of the light ray direction controller  100  is enclosed in the first light absorbing regions  34  and the second light absorbing regions  44 . The light transmitting dispersion medium  52  transmits visible light. The light transmitting dispersion medium  52  disperses the electrophoretic particles  54 . 
     The electrophoretic particles  54  of the light ray direction controller  100  are dispersed in the light transmitting dispersion medium  52  and absorb visible light. The electrophoretic particles  54  are positively or negatively charged, and the dispersion state of the electrophoretic particles  54  in the light transmitting dispersion medium  52  changes according to voltage applied by the first light transmitting electrode  12  and the second light transmitting electrode  22 . In one example, the electrophoretic particles  54  are implemented as charged carbon black particles. In the present embodiment, it is assumed that the electrophoretic particles  54  are negatively charged. 
     Next, the first light absorbing regions  34  and the second light absorbing regions  44  are described. 
     The light transmitting dispersion medium  52  and the electrophoretic particles  54  dispersed in the light transmitting dispersion medium  52  are enclosed in the first light absorbing regions  34  and the second light absorbing regions  44 . Accordingly, the first light absorbing regions  34  and the second light absorbing regions  44  function as electrophoretic element together with the first light transmitting electrode  12  and the second light transmitting electrode  22 . 
     When a potential V1 of the first light transmitting electrode  12  and a potential V2 of the second light transmitting electrode  22  are equal and voltage is not being applied to the electrophoretic particles  54 , the electrophoretic particles  54  are dispersed uniformly throughout the entirety of the first light absorbing regions  34  and the second light absorbing regions  44 , and the entirety of the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers. By controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 , the electrophoretic particles  54  can be dispersed in only the first light absorbing regions  34 , only the second light absorbing regions  44 , or the like, and the regions corresponding to the dispersion state of the electrophoretic particles  54  can be caused to function as light absorbing layers. The dispersion states of the electrophoretic particles  54  and the operations of the light ray direction control element  200  are discussed later. 
     The voltage controller  110  of the light ray direction control element  200  controls the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  to control the voltage to be applied to the electrophoretic particles  54 . In one example, the voltage controller  110  is implemented as a control circuit that includes a controller, a power supply circuit, and the like. 
     Next, the operations of the light ray direction control element  200  are described. In this description of the operations of the light ray direction control element  200 , it is assumed that a surface light source (uniformly diffusing surface light source)  500  that has a constant brightness regardless of the viewing direction is disposed on the first light transmitting substrate  10  side of the light ray direction controller  100 . The light ray direction control element  200  controls the angle distribution of light  510  that enters from the −Z direction to emit in the +Z direction. 
     Light-Blocking Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the electrophoretic particles  54  are dispersed uniformly throughout the entirety of the first light absorbing regions  34  and the second light absorbing regions  44 , Accordingly, the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers. 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and the second light absorbing regions  44  are inclined the angle θ (tan θ≥D1/H2) to the +X direction side with respect to the Z direction. As such, as illustrated in  FIG. 5 , the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Additionally, since the first light absorbing regions  34  and the second light absorbing regions  44  extend in the Y direction, when viewing a cross-section on the YZ plane as well, the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Accordingly, when the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal, the light ray direction control element  200  blocks the light  510  of the surface light source  500 . In the following, this state is referred to as the “light-blocking mode.” In the light-blocking mode, the light ray direction control element  200  blocks the emitted light of the display panel  210 . 
     First Diagonal Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), the negatively charged electrophoretic particles  54  aggregate in the second light absorbing regions  44  and are dispersed in the second light absorbing regions  44  as illustrated in  FIG. 6 . Meanwhile, there are nearly no electrophoretic particles  54  in the first light absorbing regions  34 . Accordingly, only the second light absorbing regions  44  function as light absorbing layers. In the following, this state is referred to as the “first diagonal narrow field mode.” 
     When viewing a cross-section on the XZ plane, the second light absorbing regions  44  and the second light transmitting regions  42  are inclined the angle θ (tan θ≥D1/H2) to the +X direction side with respect to the Z direction. Accordingly, in the first diagonal narrow field mode, of the light  510  that enters from the surface light source  500 , the light that has an angle, to the +X direction side with respect to the Z direction, near the angle θ is not absorbed by the second light absorbing regions  44  and exits from the light ray direction controller  100 . Additionally, in the XZ plane, the light other than the light that has an angle, to the +X direction side with respect to the Z direction, near the angle θ is absorbed by the second light absorbing regions  44 . Accordingly, in a plane parallel to the XZ plane, when the +X direction is 0°, the +Z direction is 90°, and the −X direction is 180°, the emitted light of the light ray direction control element  200  in the first diagonal narrow field mode has a narrow angle distribution near 90°−θ, as illustrated in  FIG. 7 . Note that, in the following embodiments as well, descriptions are given in which, for the angle distribution of the emitted light of the light ray direction control element  200  in a plane parallel to the XZ plane, the +X direction is 0°, the +Z direction is 90°, and the −X direction is 180°. The plane parallel to the XZ plane includes the XZ plane. 
     In the present embodiment, the second light transmitting regions  42  and the second light absorbing regions  44 , that are inclined the angle θ (tan θ≥D1/H2) to the +X direction side, extend in the Y direction. Accordingly, in a plane parallel to a plane inclined to the +X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×θ), the emitted light of the light ray direction control element  200  in the first diagonal narrow field mode has a uniform angle distribution. 
     As described above, the emitted light of the light ray direction control element  200  in the first diagonal narrow field mode has a narrow angle distribution near 90°−θ in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the plane inclined to the +X direction side with respect to the YZ plane. Accordingly, in the first diagonal narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the angle θ of the right direction (the +X direction) with respect to the front surface (the +Z direction). 
     First Perpendicular Narrow Field Mode 
     When voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), the negatively charged electrophoretic particles  54  aggregate in the first light absorbing regions  34  and are dispersed in the first light absorbing regions  34  as illustrated in  FIG. 8 . Meanwhile, there are nearly no electrophoretic particles  54  in the second light absorbing regions  44 . Accordingly, only the first light absorbing regions  34  function as light absorbing layers. In the following, this state is referred to as the “first perpendicular narrow field mode.” 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  and the first light transmitting regions  32  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the first perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34  as illustrated in  FIG. 8 . Additionally, on the XZ plane, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the first perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 7 . 
     In a plane parallel to the YZ plane, the first light transmitting regions  32  and the first light absorbing regions  34  extend in the Y direction and, as such, the emitted light of the light ray direction control element  200  in the first perpendicular narrow field mode has a uniform angle distribution. Note that the plane parallel to the YZ plane includes the YZ plane. 
     As described above, the emitted light of the light ray direction control element  200  in the first perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane. Accordingly, in the first perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     First Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and a difference between the potential V2 and the potential V1 is greater than in the first diagonal narrow field mode (V2&gt;&gt;V1), the negatively charged electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44  as illustrated in  FIG. 9 . Accordingly, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “first wide field mode.” 
     In the first wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the first wide field mode has a uniform angle distribution as illustrated in  FIG. 7 . Additionally, in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the first wide field mode has a uniform angle distribution. In the first wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Second Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the first perpendicular narrow field mode (V1&gt;&gt;V2), the negatively charged electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34  as illustrated in  FIG. 10 . Accordingly, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “second wide field mode.” 
     In the second wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the second wide field mode has a uniform angle distribution, as in the first wide field mode. In the second wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Thus, with the light ray direction control element  200 , it is possible to emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  (the voltage applied to the electrophoretic particles  54 ). 
     In the light ray direction control element  200 , when transitioning from the light-blocking mode to the first diagonal narrow field mode, it is preferable to transition from the light-blocking mode to the first diagonal narrow field mode via the first wide field mode. 
     Additionally, when transitioning from the light-blocking mode to the first perpendicular narrow field mode, it is preferable to transition from the light-blocking mode to the first perpendicular narrow field mode via the second wide field mode. By doing so, the electrophoretic particles  54  with stably disperse in the first light absorbing regions  34  or the second light absorbing regions  44 , and mode transition reproducibility can be improved. 
     Next, a specific example of transitioning from the light-blocking mode to the first diagonal narrow field mode is described. 
     The voltage controller  110  controls the voltage applied to the electrophoretic particles  54  to cause the dispersion state of the electrophoretic particles  54  to transition from a dispersion state in which the electrophoretic particles  54  are dispersed in the first light absorbing regions  34  and the second light absorbing regions  44  (the light-blocking mode) to a dispersion state in which the electrophoretic particles  54  are dispersed in the second light absorbing regions  44  but are not dispersed in the first light absorbing regions  34  (the first diagonal narrow field mode). In the light-blocking mode, voltage is not applied to the electrophoretic particles  54 . In the first diagonal narrow field mode, voltage of a first voltage value (V2&gt;V1) is applied to the electrophoretic particles  54 . In this case, the voltage controller  110  first applies voltage of a second voltage value (V2&gt;&gt;V1) greater than the first voltage value to the electrophoretic particles  54  to cause the electrophoretic particles  54  to transition from the dispersion state in which the electrophoretic particles  54  are dispersed in the first light absorbing regions  34  and the second light absorbing regions  44 , to the dispersion state in which the electrophoretic particles  54  are dispersed in the second light absorbing regions  44  but are not dispersed in the first light absorbing regions  34 , via the dispersion state (the first wide field mode) in which the electrophoretic particles  54  are aggregated in the second light absorbing regions  44 . As a result, the electrophoretic particles  54  are first aggregated in the second light absorbing regions  44  and, then, are dispersed in the second light absorbing regions  44  and, as such, a stable dispersion state can be formed. Note that the same is applicable when transitioning from the light-blocking mode to the first perpendicular narrow field mode. 
     Next, a manufacturing method of the light ray direction control element  200  is described.  FIG. 11  is a flowchart illustrating a manufacturing method for the light ray direction control element  200 . The manufacturing method for the light ray direction control element  200  includes forming the first light transmitting regions  32  on the first main surface  10   a  of the first light transmitting substrate  10  (step S 10 ), forming the second light transmitting regions  42  on the first main surface  20   a  of the second light transmitting substrate  20  (step S 20 ), adhering the first light transmitting substrate  10  and the second light transmitting substrate  20  to each other to connect the first light transmitting regions  32  to the second light transmitting regions  42  (step S 30 ), filling with the light transmitting dispersion medium  52  in which the electrophoretic particles  54  are dispersed (step S 40 ), and electrically connecting the voltage controller  110  (step S 50 ). 
     In step S 10 , a known photolithography technique is used to form the first light transmitting regions  32  on the first main surface  10   a  of the first light transmitting substrate  10  on which the first light transmitting electrode  12  and the insulation layer are provided. In one example, the first light transmitting regions  32  are formed from a chemically amplified photoresist called SU-8 (product name, Nippon Kayaku Co., Ltd.). 
     As in step S 10 , in step S 20 , the second light transmitting regions  42  are formed on the first main surface  20   a  of the second light transmitting substrate  20  on which the second light transmitting electrode  22  and the insulation layer are provided. 
     In step S 30 , the first main surface  10   a  of the first light transmitting substrate  10  and the first main surface  20   a  of the second light transmitting substrate  20  are caused to face each other, thereby stacking the second light transmitting substrate  20  on the first light transmitting substrate  10 . In this case, the second light transmitting substrate  20  may be stacked directly on the first light transmitting substrate  10 , or the first light transmitting substrate  10  and the second light transmitting substrate  20  may be adhered to each other by an adhesive. As a result, the first light transmitting regions  32  are connected to the second light transmitting regions  42 . The adhesive is a thermosetting adhesive, an ultraviolet (UV) curing adhesive, or the like. 
     In step S 40 , space between adjacent first light transmitting regions  32  and space between adjacent second light transmitting regions  42  are filled with the light transmitting dispersion medium  52  in which the electrophoretic particles  54  are dispersed. As a result, the first light absorbing regions  34  and the second light absorbing regions  44  are formed. The first light absorbing regions  34  and the second light absorbing regions  44  are sealed by an adhesive. 
     In step S 50 , the voltage controller  110  is electrically connected to the first light transmitting electrode  12  and the second light transmitting electrode  22 . Thus, the light ray direction control element  200  can be manufactured. 
     As described above, when viewing a cross-section on the XZ plane, the angles of inclination, with respect to the first main surface  10   a  of the first light transmitting substrate  10 , of the first light transmitting regions  32  and the second light transmitting regions  42  differ and, as such, the light ray direction control element  200  can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  (the voltage applied to the electrophoretic particles  54 ). 
     Embodiment 2 
     The first light transmitting regions  32  and the first light absorbing regions  34  of Embodiment 1 are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . However, a configuration is possible in which, when viewing a cross-section on the XZ plane, the first light transmitting regions  32  and the first light absorbing regions  34  are inclined with respect to the direction (the +Z direction) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . 
     In the light ray direction control element  200  of the present embodiment, the configurations of the first light transmitting regions  32  and the first light absorbing regions  34  differ from the configurations of the first light transmitting regions  32  and the first light absorbing regions  34  of Embodiment 1. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of Embodiment 1. Next, the configurations of the first light transmitting regions  32  and the first light absorbing regions  34 , and the operations of the light ray direction control element  200  are described. 
     As with the first light transmitting regions  32  of Embodiment 1, the first light transmitting regions  32  of the present embodiment are regions that transmit visible light. Additionally, the first light transmitting regions  32  of the present embodiment are provided on the first main surface  10   a  of the first light transmitting substrate  10 . 
     As with the second light transmitting regions  42 , as illustrated in  FIG. 12 , the first light transmitting regions  32  of the present embodiment have an oblique quadrangular prism shape and are arranged in the X direction. As illustrated in  FIG. 13 , when viewing a cross-section (XZ plane) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10  and the first main surface  20   a  of the second light transmitting substrate  20 , the first light transmitting regions  32  of the present embodiment are inclined at an angle φ (tan φ≥D1/H1) to the −X direction side with respect to the direction (the +Z direction) perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . That is, the first light transmitting regions  32  of the present embodiment are inclined in the reverse direction of the second light transmitting regions  42  with respect to the +Z direction. The other configurations of the first light transmitting regions  32  of the present embodiment are the same as the configurations of the first light transmitting regions  32  of Embodiment 1. 
     As with the first light absorbing regions  34  of Embodiment 1, the first light absorbing regions  34  of the present embodiment are regions between adjacent first light transmitting regions  32 . When viewing a cross-section on the XZ plane, the first light transmitting regions  32  are inclined the angle φ to the −X direction side with respect to the +Z direction and, as such, the first light absorbing regions  34  of the present embodiment are also inclined the angle φ to the −X direction side with respect to the +Z direction. The other configurations of the first light absorbing regions  34  of the present embodiment are the same as the configurations of the first light absorbing regions  34  of Embodiment 1. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. As in Embodiment 1, the operations of the light ray direction control element  200  of the present embodiment are described under the assumption that the surface light source  500  is disposed on the first light transmitting substrate  10  side of the light ray direction controller  100 . 
     Light-Blocking Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  are inclined the angle φ (tan φ≥D1/H1) to the −X direction side with respect to the Z direction, and the second light absorbing regions  44  are inclined the angle θ (tan θ≥D1/H2) to the +X direction side with respect to the Z direction. As such, as with the light-blocking mode of Embodiment 1, the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Additionally, since the first light absorbing regions  34  and the second light absorbing regions  44  extend in the Y direction, when viewing a cross-section on the YZ plane as well, the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Accordingly, when the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal, as with the light ray direction control element  200  of Embodiment 1, the light ray direction control element  200  of the present embodiment blocks the light  510  of the surface light source  500 . That is, the light ray direction control element  200  blocks the emitted light of the display panel  210 . 
     Second Diagonal Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “second diagonal narrow field mode.” 
     The configuration of the second light absorbing regions  44  of the present embodiment is the same as that of the second light absorbing regions  44  of Embodiment 1. As such, in the XZ plane in the second diagonal narrow field mode, of the light  510  that enters from the surface light source  500 , the light that has an angle, to the +X direction side with respect to the Z direction, near the angle θ exits from the light ray direction controller  100 . Additionally, in the XZ plane of the second diagonal narrow field mode, the light other than the light that has an angle, to the +X direction side with respect to the Z direction, near the angle θ is absorbed by the second light absorbing regions  44 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the second diagonal narrow field mode has a narrow angle distribution near 90°−θ, the same as in the first diagonal narrow field mode ( FIGS. 6 and 7 ) of Embodiment 1. 
     The second light transmitting regions  42  and the second light absorbing regions  44  that are inclined the angle θ (tan θ≥D1/H2) to the +X direction side extend in the Y direction and, as such, in a plane parallel to a plane inclined to the +X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×θ), the emitted light of the light ray direction control element  200  in the second diagonal narrow field mode has a uniform angle distribution. 
     As described above, the emitted light of the light ray direction control element  200  in the second diagonal narrow field mode has a narrow angle distribution near 90°−θ in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to a plane inclined to the +X direction side with respect to the YZ plane. Accordingly, in the second diagonal narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the angle θ of the right direction (the +X direction) with respect to the front surface (the +Z direction). 
     Third Diagonal Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), the electrophoretic particles  54  aggregate in the first light absorbing regions  34  and are dispersed in the first light absorbing regions  34  as illustrated in  FIG. 14 . Meanwhile, there are nearly no electrophoretic particles  54  in the second light absorbing regions  44 . Accordingly, only the first light absorbing regions  34  function as light absorbing layers. In the following, this state is referred to as the “third diagonal narrow field mode.” 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  and the first light transmitting regions  32  are inclined the angle φ (tan φ≥D1/H1) to the −X direction side with respect to the +Z direction. As such, in the third diagonal narrow field mode, of the light  510  that enters from the surface light source  500 , the light that has an angle, to the −X direction side with respect to the Z direction, near the angle φ exits from the light ray direction controller  100  without being absorbed by the first light absorbing regions  34 . Additionally, in the XZ plane, the light other than the light that has an angle, to the +X direction side with respect to the +Z direction, near the angle θ is absorbed by the first light absorbing regions  34 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the third diagonal narrow field mode has a narrow angle distribution near 90°+φ, as illustrated in  FIG. 15 . 
     The first light transmitting regions  32  and the first light absorbing regions  34  inclined the angle φ (tan φ≥D1/H1) to the −X direction side extend in the Y direction and, as such, in a plane parallel to a plane inclined to the −X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×φ), the emitted light of the light ray direction control element  200  in the third diagonal narrow field mode has a uniform angle distribution. 
     As described above, the emitted light of the light ray direction control element  200  in the third diagonal narrow field mode has a narrow angle distribution near 90°+φ in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to a plane inclined to the −X direction side with respect to the YZ plane. Accordingly, in the third diagonal narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the angle φ of the left direction (the −X direction) with respect to the front surface (the +Z direction). 
     Third Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the second diagonal narrow field mode (V2&gt;&gt;V1), as in the first wide field mode of Embodiment 1, the electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44  (hereinafter referred to as the “third wide field mode”). Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the third wide field mode has a uniform angle distribution, as in the first wide field mode of Embodiment 1. In the third wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Fourth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the third diagonal narrow field mode (V1&gt;&gt;V2), as in the second wide field mode of Embodiment 1, the electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34  (hereinafter referred to as the “fourth wide field mode”). Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the fourth wide field mode has a uniform angle distribution, as in the second wide field mode of Embodiment 1. In the fourth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Thus, when viewing a cross-section on the XZ plane, the angles of inclination, with respect to the first main surface  10   a  of the first light transmitting substrate  10 , of the first light transmitting regions  32  and the second light transmitting regions  42  differ and, as such, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 3 
     A configuration is possible in which the first light transmitting regions  32  and the second light transmitting regions  42  of the light ray direction controller  100  are arranged in the X direction and the Y direction. In the light ray direction control element  200  of the present embodiment, the configurations of the first light transmitting regions  32 , the first light absorbing regions  34 , the second light transmitting regions  42 , and the second light absorbing regions  44  differ from those of Embodiment 1. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of Embodiment 1. Next, the configurations of the first light transmitting regions  32 , the first light absorbing regions  34 , the second light transmitting regions  42 , and the second light absorbing regions  44 , and the operations of the light ray direction control element  200  are described. 
     As with the first light transmitting regions  32  of Embodiment 1, the first light transmitting regions  32  of the present embodiment are regions that transmit visible light. Additionally, the first light transmitting regions  32  of the present embodiment are provided on the first main surface  10   a  of the first light transmitting substrate  10 . 
     As illustrated in  FIG. 16 , the first light transmitting regions  32  of the present embodiment have a quadrangular prism shape and are arranged in a matrix in the X direction and the Y direction. As with the first light transmitting regions  32  of Embodiment 1, the first light transmitting regions  32  of the present embodiment extend from the first light transmitting substrate  10  toward the second light transmitting substrate  20 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and are continuous with the second light transmitting regions  42 . The other configurations of the first light transmitting regions  32  of the present embodiment are the same as the configurations of the first light transmitting regions  32  of Embodiment 1. 
     As with the first light absorbing regions  34  of Embodiment 1, the first light absorbing regions  34  of the present embodiment are regions between adjacent first light transmitting regions  32 . In the present embodiment, the quadrangular prism shaped first light transmitting regions  32  are arranged in a matrix and, as such, the first light absorbing regions  34  form a lattice-shaped region. As with the first light transmitting regions  32  of the present embodiment, the first light absorbing regions  34  of the present embodiment are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . The other configurations of the first light absorbing regions  34  of the present embodiment are the same as the configurations of the first light absorbing regions  34  of Embodiment 1. 
     As with the second light transmitting regions  42  of Embodiment 1, the second light transmitting regions  42  of the present embodiment are regions that transmit visible light. The second light transmitting regions  42  of the present embodiment have an oblique quadrangular prism shape and are arranged in a matrix in the X direction and the Y direction. The second light transmitting regions  42  of the present embodiment extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , and are continuous with the first light transmitting regions  32 . As with the second light transmitting regions  42  of Embodiment 1, when viewing a cross-section on the XZ plane, the second light transmitting regions  42  of the present embodiment are inclined the angle θ (tan θ≥D1/H2) to the +X direction side with respect to the Z direction. The other configurations of the second light transmitting regions  42  of the present embodiment are the same as the configurations of the second light transmitting regions  42  of Embodiment 1. 
     As with the second light absorbing regions  44  of Embodiment 1, the second light absorbing regions  44  of the present embodiment are regions between adjacent second light transmitting regions  42 . In the present embodiment, oblique quadrangular prism shaped second light transmitting regions  42  are arranged in a matrix and, as such, the second light absorbing regions  44  of the present embodiment form a lattice-shaped region in which an X direction side surface is inclined the angle θ to the +X direction side. The other configurations of the second light absorbing regions  44  of the present embodiment are the same as the configurations of the second light absorbing regions  44  of Embodiment 1. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. As in Embodiment 1, the operations of the light ray direction control element  200  of the present embodiment are described under the assumption that the surface light source  500  is disposed on the first light transmitting substrate  10  side of the light ray direction controller  100 . Note that, in the following embodiment, the operations of the light ray direction control element  200  are described under the assumption that the surface light source  500  is disposed on the first light transmitting substrate  10  side of the light ray direction controller  100 . 
     Light-Blocking Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. 
     When viewing a cross-section on the XZ plane, as with the light-blocking mode of Embodiment 1, the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Additionally, when viewing a cross-section on the YZ plane as well, the first light absorbing regions  34  and the second light absorbing regions  44  that function as light absorbing layers absorb all of the light  510  that enters from the surface light source  500 . Accordingly, when the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal, as with the light ray direction control element  200  of Embodiment 1, the light ray direction control element  200  of the present embodiment blocks the light  510  of the surface light source  500 . That is, the light ray direction control element  200  blocks the emitted light of the display panel  210 . 
     Fourth Diagonal Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “fourth diagonal narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the second light transmitting regions  42 , the second light absorbing regions  44  and the second light transmitting regions  42  are inclined the angle θ (tan θ≥D1/H2) to the +X direction side with respect to the Z direction. Accordingly, in a plane parallel to the XZ plane that includes the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the fourth diagonal narrow field mode has a narrow angle distribution near 90°−θ, the same as in the first diagonal narrow field mode of Embodiment 1. Meanwhile, when viewing a cross-section on a plane parallel to the XZ plane that includes a lattice portion of the second light absorbing regions  44 , the second light absorbing regions  44  extend in the X direction and, as such, in the fourth diagonal narrow field mode, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . 
     When viewing a cross-section on a plane parallel to the plane inclined to the +X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×θ), the second light absorbing regions  44  and the second light transmitting regions  42  are alternately disposed in the Y direction. Accordingly, in a plane parallel to the plane inclined to the +X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×θ), the emitted light of the light ray direction control element  200  in the fourth diagonal narrow field mode has a narrow angle distribution. 
     As described above, the emitted light of the light ray direction control element  200  in the fourth diagonal narrow field mode has a narrow angle distribution near 90°−θ in a plane parallel to the XZ plane that includes the second light transmitting regions  42 , and has a narrow angle distribution in a plane parallel to the plane inclined to the +X direction side with respect to the YZ plane. Accordingly, in the fourth diagonal narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the angle θ of the right direction (the +X direction) with respect to the front surface (the +Z direction). Additionally, the light ray direction control element  200  can narrow the viewing angle in the vertical direction (the Y direction) of the display device  300 . 
     Second Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), only the first light absorbing regions  34  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “second perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32 , the first light absorbing regions  34  and the first light transmitting regions  32  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . Accordingly, in a plane parallel to the XZ plane that includes the first light transmitting regions  32 , the emitted light of the light ray direction control element  200  in the second perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), the same as in the first perpendicular narrow field mode of Embodiment 1 ( FIGS. 7 and 8 ). Meanwhile, when viewing a cross-section on a plane parallel to the XZ plane that includes a lattice portion of the first light absorbing regions  34 , the first light absorbing regions  34  extend in the X direction and, as such, in the second perpendicular narrow field mode, the light  510  that enters from the surface light source  500  is absorbed by the first light absorbing regions  34 . 
     When viewing a cross-section on a plane parallel to the YZ plane that includes the first light transmitting regions  32 , the first light absorbing regions  34  and the first light transmitting regions  32  of the present embodiment are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the second perpendicular narrow field mode of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34  as illustrated in  FIG. 17 . Additionally, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the YZ plane, when the +Y direction is 0°, the +Z direction is 90°, and the −Y direction is 180°, in a plane parallel to the YZ plane that includes the first light transmitting regions  32 , the emitted light of the light ray direction control element  200  in the second perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 18 . Meanwhile, when viewing a cross-section on a plane parallel to the YZ plane that includes a lattice portion of the first light absorbing regions  34 , the first light absorbing regions  34  extend in the Y direction and, as such, in the second perpendicular narrow field mode, the light  510  that enters from the surface light source  500  is absorbed by the first light absorbing regions  34 . Note that, in the following embodiments, descriptions are given in which, for the angle distribution of the emitted light of the light ray direction control element  200  in a plane parallel to the YZ plane (the vertical direction), the +Y direction is 0°, the +Z direction is 90°, and the −Y direction is 180°. 
     As described above, the emitted light of the light ray direction control element  200  in the second perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane that includes the first light transmitting regions  32 , and has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the YZ plane that includes the first light transmitting regions  32 . Accordingly, in the second perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle of the display device  300  to near the front surface (the +Z direction). 
     Fifth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the fourth diagonal narrow field mode (V2&gt;&gt;V1), as in the first wide field mode of Embodiment 1, the electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44  (hereinafter referred to as the “fifth wide field mode”). Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the fifth wide field mode has a uniform angle distribution, as in the first wide field mode of Embodiment 1. In the fifth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Sixth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the second perpendicular narrow field mode (V1&gt;&gt;V2), as in the second wide field mode of Embodiment 1, the electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34  (hereinafter referred to as the “sixth wide field mode”). Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the sixth wide field mode has a uniform angle distribution, as in the second wide field mode of Embodiment 1. In the sixth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Thus, as with the light ray direction control element  200  of Embodiment 1 and Embodiment 2, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 4 
     A configuration is possible in which, when viewing a cross-section on the XZ plane, the shape of the first light transmitting regions  32  and the shape of the second light transmitting regions  42  are different. With the light ray direction control element  200  of the present embodiment, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44  differ from those of Embodiment 1. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of Embodiment 1. Next, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44 , and the operations of the light ray direction control element  200  are described. 
     As with the second light transmitting regions  42  of Embodiment 1, the second light transmitting regions  42  of the present embodiment are regions that transmit visible light. The second light transmitting regions  42  of the present embodiment are provided on the first main surface  20   a  of the second light transmitting substrate  20 . 
     As illustrated in  FIGS. 19 and 20 , the second light transmitting regions  42  of the present embodiment have a rectangular parallelepiped shape that extends in the Y direction, and are arranged at a predetermined spacing in the X direction. A width D2 in the X direction of the second light transmitting regions  42  of the present embodiment is narrower than the width D1 (the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1) in the X direction of the first light transmitting regions  32  of the present embodiment (D2&lt;D1). Accordingly, when viewing a cross-section on the XZ plane, the shape of the first light transmitting regions  32  and the shape of the second light transmitting regions  42  are different. 
     The second light transmitting regions  42  of the present embodiment extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and are continuous with the first light transmitting regions  32 . The other configurations of the second light transmitting regions  42  of the present embodiment are the same as those of the second light transmitting regions  42  of Embodiment 1. 
     As with the second light absorbing regions  44  of Embodiment 1, the second light absorbing regions  44  of the present embodiment are regions between adjacent second light transmitting regions  42 . As with the second light transmitting regions  42 , the second light absorbing regions  44  of the present embodiment extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . Additionally, the second light absorbing regions  44  of the present embodiment extend in the Y direction. In the present embodiment, the width D2 in the X direction of the second light transmitting regions  42  is narrower than the width D1 in the X direction of the first light transmitting regions  32  and, as such, the width in the X direction of the second light absorbing regions  44  of the present embodiment is wider than the width in the X direction of the first light absorbing regions  34 . The other configurations of the second light absorbing regions  44  of the present embodiment are the same as those of the second light absorbing regions  44  of Embodiment 1. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. 
     Third Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “third perpendicular narrow field mode.” 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  and the second light absorbing regions  44  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the third perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34  and the second light absorbing regions  44  as illustrated in  FIG. 21 . Additionally, on the XZ plane, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the third perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 22 . In the present embodiment, the width D2 in the X direction of the second light transmitting regions  42  is narrower than the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1. As such, the angle distribution of the emitted light of the third perpendicular narrow field mode is narrower than the angle distribution of the emitted light of the first perpendicular narrow field mode of Embodiment 1, and the transmittance in the third perpendicular narrow field mode is lower than the transmittance in the first perpendicular narrow field mode. 
     Accordingly, in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the first light transmitting regions  32  and the second light transmitting regions  42  extend in the Y direction and, as such, the emitted light of the light ray direction control element  200  in the third perpendicular narrow field mode has a uniform angle distribution. In another plane parallel to the YZ plane, the first light absorbing regions  34  and the second light absorbing regions  44  extend in the Y direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the first light absorbing regions  34  and the second light absorbing regions  44 . 
     As described above, the emitted light of the light ray direction control element  200  in the third perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 . Accordingly, in the third perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Fourth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “fourth perpendicular narrow field mode.” 
     When viewing a cross-section on the XZ plane, the second light absorbing regions  44  and the second light transmitting regions  42  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the fourth perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44  as in the third perpendicular narrow field mode. Additionally, on the XZ plane, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . 
     In a plane parallel to the YZ plane that includes the second light transmitting regions  42 , the second light transmitting regions  42  extend in the Y direction and, as such, the emitted light of the light ray direction control element  200  in the fourth perpendicular narrow field mode has a uniform angle distribution. In another plane parallel to the YZ plane, the second light absorbing regions  44  extend in the Y direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . Accordingly, in the fourth perpendicular narrow field mode, light having the same angle distribution as in the third perpendicular narrow field mode exits from the light ray direction control element  200 . 
     As described above, in the fourth perpendicular narrow field mode, light having the same angle distribution as in the third perpendicular narrow field mode exits from the light ray direction control element  200 . Accordingly, in the fourth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Fifth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), only the first light absorbing regions  34  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “fifth perpendicular narrow field mode.” 
     When viewing a cross-section on the XZ plane, the first light absorbing regions  34  and the first light transmitting regions  32  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the fifth perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34 . Additionally, on the XZ plane, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the fifth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 22 . 
     In a plane parallel to the YZ plane that includes the first light transmitting regions  32 , the first light transmitting regions  32  extend in the Y direction. Accordingly, in a plane parallel to the YZ plane that includes the first light transmitting regions  32 , the emitted light of the light ray direction control element  200  in the fifth perpendicular narrow field mode has a uniform angle distribution. Meanwhile, in a plane parallel to the YZ plane that includes the first light absorbing regions  34 , the first light absorbing regions  34  extend in the Y direction and, as such, in the fifth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  is absorbed by the first light absorbing regions  34 . 
     In the present embodiment, the width D1 in the X direction of the first light transmitting regions  32  is wider than the width D2 in the X direction of the second light transmitting regions  42  and, as such, the angle distribution of the emitted light of the fifth perpendicular narrow field mode is wider than the angle distribution of the emitted light of the third perpendicular narrow field mode and the fourth perpendicular narrow field mode. Additionally, the transmittance in the fifth perpendicular narrow field mode is higher than the transmittance in the third perpendicular narrow field mode and the fourth perpendicular narrow field mode. 
     As described above, the emitted light of the light ray direction control element  200  in the fifth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane that includes the first light transmitting regions  32 . Accordingly, in the fifth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Seventh Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the fourth perpendicular narrow field mode (V2&gt;&gt;V1), as in Embodiment 1, the electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “seventh wide field mode.” 
     In the seventh wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the seventh wide field mode has a uniform angle distribution as illustrated in  FIG. 22 . In the present embodiment, the width D2 in the X direction of the second light transmitting regions  42  is narrower than the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1 and, as such, the transmittance in the seventh wide field mode is lower than the transmittance in the first wide field mode. Additionally, in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the seventh wide field mode has a uniform angle distribution. In the seventh wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Eighth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the fifth perpendicular narrow field mode (V1&gt;&gt;V2), as in Embodiment 1, the electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “eighth wide field mode.” 
     In the eighth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the eighth wide field mode has a uniform angle distribution as illustrated in  FIG. 22 . Additionally, in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the eighth wide field mode has a uniform angle distribution. In the eighth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     In the present embodiment, the width D1 in the X direction of the first light transmitting regions  32  is wider than the width D2 in the X direction of the second light transmitting regions  42  and, as such, the transmittance in the eighth wide field mode is higher than the transmittance in the seventh wide field mode. 
     As described above, when viewing a cross-section on the XZ plane, the shape of the first light transmitting regions  32  differs from the shape of the second light transmitting regions  42  and, as such, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 5 
     The second light transmitting regions  42  of Embodiment 4 are arranged in the X direction, but a configuration is possible in which the second light transmitting regions  42  are arranged in a matrix. With the light ray direction control element  200  of the present embodiment, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44  differ from those of Embodiment 4. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of Embodiment 4. Next, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44  and the operations of the light ray direction control element  200  are described. 
     As with the second light transmitting regions  42  of Embodiment 4, the second light transmitting regions  42  of the present embodiment are regions that transmit visible light. The second light transmitting regions  42  of the present embodiment are provided on the first main surface  20   a  of the second light transmitting substrate  20 . 
     As illustrated in  FIG. 23 , the second light transmitting regions  42  of the present embodiment have a quadrangular prism shape and are arranged in a matrix in the X direction and the Y direction. The width D2 in the X direction of the second light transmitting regions  42  of the present embodiment is narrower than the width D1 (the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1) in the X direction of the first light transmitting regions  32  of the present embodiment. The second light transmitting regions  42  of the present embodiment extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and are continuous with the first light transmitting regions  32 . In the present embodiment, as with the first light transmitting regions  32  of Embodiment 4, the first light transmitting regions  32  have a rectangular parallelepiped that extends in the Y direction and, as such, the second light transmitting regions  42  and the first light transmitting regions  32  have a configuration in which a plurality of the second light transmitting regions  42  is arranged in the Y direction (predetermined first direction) on one first light transmitting region  32 . The other configurations of the second light transmitting regions  42  of the present embodiment are the same as the configurations of the second light transmitting regions  42  of Embodiment 4. 
     As with the second light absorbing regions  44  of Embodiment 4, the second light absorbing regions  44  of the present embodiment are regions between adjacent second light transmitting regions  42 . In the present embodiment, the quadrangular prism shaped second light transmitting regions  42  are arranged in a matrix and, as such, the second light absorbing regions  44  form a lattice-shaped region. The second light absorbing regions  44  of the present embodiment are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . The other configurations of the second light absorbing regions  44  of the present embodiment are the same as the configurations of the second light absorbing regions  44  of Embodiment 4. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. 
     Sixth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “sixth perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the first light absorbing regions  34  and the second light absorbing regions  44  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the sixth perpendicular narrow field mode, as in the third perpendicular narrow field mode ( FIG. 21 ) of Embodiment 4, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34  and the second light absorbing regions  44 . Additionally, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the sixth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), the same as in the third perpendicular narrow field mode. Meanwhile, when viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light absorbing regions  44 , the second light absorbing regions  44  extend in the X direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . 
     In the present embodiment, the width D2 in the X direction of the second light transmitting regions  42  is narrower than the width D1 in the X direction of the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1 and, as such, as in the third perpendicular narrow field mode, the angle distribution of the emitted light of the sixth perpendicular narrow field mode is narrower than the angle distribution of the emitted light of the first perpendicular narrow field mode of Embodiment 1. Additionally, the transmittance in the sixth perpendicular narrow field mode is lower than the transmittance in the first perpendicular narrow field mode. 
     When viewing a cross-section on a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the second light transmitting regions  42  have a quadrangular prism shape. As such, in the sixth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32 , and of the light that transmits through the first light transmitting regions  32 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44  as illustrated in  FIG. 24 . Additionally, of the light that transmits through the first light transmitting regions  32 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the sixth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 25 . Meanwhile, when viewing a cross-section on a plane parallel to the YZ plane that includes the second light absorbing regions  44 , the second light absorbing regions  44  extend in the Y direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . 
     As described above, the emitted light of the light ray direction control element  200  in the sixth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , and has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 . Accordingly, in the sixth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle of the display device  300  to near the front surface (the +Z direction). 
     Seventh Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “seventh perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the second light absorbing regions  44  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the seventh perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 , as in the sixth perpendicular narrow field mode. Additionally, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Furthermore, in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42  as well, the light near the +Z direction exits from the light ray direction controller  100 , as in the sixth perpendicular narrow field mode. Accordingly, in the seventh perpendicular narrow field mode, light having the same angle distribution as in the sixth perpendicular narrow field mode exits from the light ray direction control element  200 . 
     As described above, in the seventh perpendicular narrow field mode, light having the same angle distribution as in the sixth perpendicular narrow field mode exits from the light ray direction control element  200 . Accordingly, in the seventh perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle of the display device  300  to near the front surface (the +Z direction), as in the sixth perpendicular narrow field mode. 
     Eighth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), only the first light absorbing regions  34  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “eighth perpendicular narrow field mode.” 
     The first light transmitting regions  32  and the first light absorbing regions  34  of the present embodiment respectively have the same shapes as the first light transmitting regions  32  and the first light absorbing regions  34  of Embodiment 4. Accordingly, in the eighth perpendicular narrow field mode, light having the same angle distribution as in the fifth perpendicular narrow field mode of Embodiment 4 exits from the light ray direction control element  200 . Additionally, in the eighth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction), as in the fifth perpendicular narrow field mode. 
     Ninth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the seventh perpendicular narrow field mode (V2&gt;&gt;V1), as in Embodiment 1, the electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “ninth wide field mode.” 
     In the ninth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the ninth wide field mode has a uniform angle distribution. In the ninth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . In the present embodiment, the width D2 in the X direction of the second light transmitting regions  42  is narrower than the width D1 in the X direction of the first light transmitting regions  32  of Embodiment 1 and the second light absorbing regions  44  have a lattice shape and, as such, the transmittance in the ninth wide field mode is lower than the transmittance in the first wide field mode. 
     Tenth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the eighth perpendicular narrow field mode (V1&gt;&gt;V2), as in Embodiment 1, the electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “tenth wide field mode.” 
     In the tenth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the tenth wide field mode has a uniform angle distribution. In the tenth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . In the present embodiment, the width D1 in the X direction of the first light transmitting regions  32  is wider than the width D2 in the X direction of the second light transmitting regions  42  and, as such, the transmittance in the tenth wide field mode is higher than the transmittance in the ninth wide field mode. 
     Thus, as with the light ray direction control element  200  of Embodiment 4, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 6 
     In Embodiment 4, the first light transmitting regions  32  and the second light transmitting regions  42  have rectangular parallelepiped shapes that extend in the Y direction, but a configuration is possible in which the first light transmitting regions  32  and the second light transmitting regions  42  have rectangular parallelepiped shapes that extend in different directions. With the light ray direction control element  200  of the present embodiment, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44  differ from those of Embodiment 4. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of Embodiment 4. Next, the configurations of the second light transmitting regions  42  and the second light absorbing regions  44 , and the operations of the light ray direction control element  200  are described. 
     As with the second light transmitting regions  42  of Embodiment 4, the second light transmitting regions  42  of the present embodiment are regions that transmit visible light. the second light transmitting regions  42  of the present embodiment are provided on the first main surface  20   a  of the second light transmitting substrate  20 . As illustrated in  FIG. 26 , the second light transmitting regions  42  of the present embodiment have a rectangular parallelepiped shape that extends in the X direction, and are arranged at a predetermined spacing in Y direction. Accordingly, when viewing a cross-section on the XZ plane, the shape of the first light transmitting regions  32  and the shape of the second light transmitting regions  42  are different. 
     The second light transmitting regions  42  of the present embodiment extend from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 , and are continuous with the first light transmitting regions  32 . The other configurations of the second light transmitting regions  42  of the present embodiment are the same as those of the second light transmitting regions  42  of Embodiment 4. 
     As with the second light absorbing regions  44  of Embodiment 4, the second light absorbing regions  44  of the present embodiment are regions between adjacent second light transmitting regions  42 . In the present embodiment, the second light absorbing regions  44  extend in the X direction, the same as the second light transmitting regions  42 . Additionally, as with the second light transmitting regions  42 , the second light absorbing regions  44  extend, from the second light transmitting substrate  20  toward the first light transmitting substrate  10 , perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . The other configurations of the second light absorbing regions  44  of the present embodiment are the same as those of the second light absorbing regions  44  of Embodiment 4. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. 
     Ninth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “ninth perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the first light absorbing regions  34  are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . As such, in the ninth perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the first light absorbing regions  34 , as illustrated in  FIG. 27 . Additionally, of the light  510  that enters transmits the surface light source  500 , the light near the +Z direction transmits through the first light transmitting regions  32 . The light that transmits through the first light transmitting regions  32  transmits through the second light transmitting regions  42  and exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the ninth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 28 . Meanwhile, when viewing a cross-section on a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light absorbing regions  44 , in the ninth perpendicular narrow field mode, the second light absorbing regions  44  extend in the X direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . 
     In the present embodiment, the second light absorbing regions  44  that extend in the X direction absorb a portion of the light that transmits through the first light absorbing regions  34  and, as such, the transmittance in the ninth perpendicular narrow field mode is low. 
     When viewing a cross-section on a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , as with the sixth perpendicular narrow field mode ( FIG. 24 ) of Embodiment 5, in the ninth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32  and, of the light that transmits through the first light transmitting regions  32 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 . Of the light that transmits through the first light transmitting regions  32 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the ninth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 29 . Meanwhile, when viewing a cross-section on a plane parallel to the YZ plane that includes the first light absorbing regions  34  and the second light transmitting regions  42 , in the ninth perpendicular narrow field mode, the first light absorbing regions  34  extend in the Y direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the first light absorbing regions  34 . 
     As described above, the emitted light of the light ray direction control element  200  in the ninth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 , and has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the YZ plane that includes the first light transmitting regions  32  and the second light transmitting regions  42 . Accordingly, in the ninth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle of the display device  300  to near the front surface (the +Z direction). 
     Tenth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “tenth perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes the second light absorbing regions  44 , as illustrated in  FIG. 30 , in the tenth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32  and the first light absorbing regions  34  and, then, is absorbed by the second light absorbing regions  44  that extend in the X direction. Meanwhile, when viewing a cross-section on a plane parallel to the XZ plane that includes the second light transmitting regions  42 , as illustrated in  FIG. 31 , the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32  and the first light absorbing regions  34  and, then, transmits through the second light transmitting regions  42 . Accordingly, in a plane parallel to the XZ plane that includes the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the tenth perpendicular narrow field mode has a uniform angle distribution, as illustrated in  FIG. 28 . 
     When viewing a cross-section on the YZ plane, in the tenth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32  and the first light absorbing regions  34 . Of the light that transmits through the first light transmitting regions  32  and the first light absorbing regions  34 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 . Of the light that transmits through the first light transmitting regions  32  and the first light absorbing regions  34 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the tenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 29 . 
     Since the light  510  that enters from the surface light source  500  is not absorbed by the first light absorbing regions  34 , the transmittance in the tenth perpendicular narrow field mode is higher than the transmittance in the ninth perpendicular narrow field mode. 
     As described above, the emitted light of the light ray direction control element  200  in the tenth perpendicular narrow field mode has a uniform angle distribution in a plane parallel to the XZ plane that includes the second light transmitting regions  42 , and has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the YZ plane. Accordingly, in the tenth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the vertical direction (the Y direction) of the display device  300  to near the front surface (the +Z direction). 
     Eleventh Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), only the first light absorbing regions  34  function as light absorbing layers, as in Embodiment 1. In the following, this state is referred to as the “eleventh perpendicular narrow field mode.” 
     The first light transmitting regions  32  and the first light absorbing regions  34  of the present embodiment respectively have the same shapes as the first light transmitting regions  32  and the first light absorbing regions  34  of Embodiment 4. When viewing a cross-section on the XZ plane, in the eleventh perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 , as in the fifth perpendicular narrow field mode of Embodiment 4. Additionally, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the eleventh perpendicular narrow field mode has the same narrow angle distribution near 90° (the +Z direction) as in the fifth perpendicular narrow field mode, as illustrated in  FIG. 28 . Additionally in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the eleventh perpendicular narrow field mode has the same uniform angle distribution as in the fifth perpendicular narrow field mode, as illustrated in  FIG. 29 . 
     Since the light  510  that enters from the surface light source  500  is not absorbed by the second light absorbing regions  44 , the transmittance in the eleventh perpendicular narrow field mode is higher than the transmittance in the ninth perpendicular narrow field mode. 
     As described above, the emitted light of the light ray direction control element  200  in the eleventh perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane. Accordingly, in the eleventh perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Eleventh Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the tenth perpendicular narrow field mode (V2&gt;&gt;V1), as in Embodiment 1, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “eleventh wide field mode.” 
     In the eleventh wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the eleventh wide field mode has a uniform angle distribution. In the eleventh wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Twelfth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the eleventh perpendicular narrow field mode (V1&gt;&gt;V2), as in Embodiment 1, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “twelfth wide field mode.” 
     In the twelfth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the twelfth wide field mode has a uniform angle distribution. In the twelfth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Thus, as with the light ray direction control element  200  of Embodiment 4, the light ray direction control element  200  of the present embodiment can emit light in three or more angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 7 
     In Embodiment 4, the rectangular parallelepiped first light transmitting regions  32  are arranged in the X direction, and the first light absorbing regions  34  are disposed between adjacent first light transmitting regions  32 , but a configuration is possible in which the first light transmitting regions  32  have a lattice shape, and the first light absorbing regions  34  are provided in the openings of the lattice. In the light ray direction control element  200  of the present embodiment, the configurations of the first light transmitting regions  32 , the first light absorbing regions  34 , the second light transmitting regions  42 , and the second light absorbing regions  44  differ from those in the other embodiments. The other configurations of the light ray direction control element  200  of the present embodiment are the same as the configurations of the light ray direction control element  200  of the other embodiments. Next, the configurations of the first light transmitting regions  32 , the first light absorbing regions  34 , the second light transmitting regions  42 , and the second light absorbing regions  44 , and the operations of the light ray direction control element  200  are described. 
     As in the other embodiments, the first light transmitting regions  32  of the present embodiment are regions that transmit visible light. The first light transmitting regions  32  of the present embodiment are provided on the first main surface  10   a  of the first light transmitting substrate  10 . As illustrated in  FIG. 32 , the first light transmitting regions  32  of the present embodiment have a lattice shape. The other configurations of the first light transmitting regions  32  of the present embodiment are the same as in the other embodiments. 
     The first light absorbing regions  34  of the present embodiment are regions in the openings of the lattice of the first light transmitting regions  32 , and are positioned between the first light transmitting regions  32 . Accordingly, the first light absorbing regions  34  of the present embodiment have a quadrangular prism shape and are disposed in a matrix in the X direction and the Y direction. The other configurations of the first light absorbing regions  34  of the present embodiment are the same as in the other embodiments. 
     As in the other embodiments, the second light transmitting regions  42  of the present embodiment are regions that transmit visible light, and are provided on the first main surface  20   a  of the second light transmitting substrate  20 . As illustrated in  FIGS. 32 and 33 , the second light transmitting regions  42  of the present embodiment have a rectangular parallelepiped shape that extends in the Y direction (predetermined second direction), and are arranged in the X direction. When viewed from above, the second light transmitting regions  42  of the present embodiment are positioned on a lattice that extends in the Y direction of the first light transmitting regions  32 , and are connected to the first light transmitting regions  32 . A width D4 in the X direction of the second light transmitting regions  42  of the present embodiment is narrower than a width D3 in the X direction of the lattice of the first light transmitting regions  32 . Accordingly, when viewing a cross-section on the XZ plane, the shape of the first light transmitting regions  32  and the shape of the second light transmitting regions  42  are different. The other configurations of the second light transmitting regions  42  of the present embodiment are the same as in the other embodiments. 
     As in the other embodiments, the second light absorbing regions  44  of the present embodiment are regions between adjacent second light transmitting regions  42 . The second light absorbing regions  44  of the present embodiment extend in the Y direction. The other configurations of the second light absorbing regions  44  of the present embodiment are the same as in the other embodiments. 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. 
     Twelfth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal (V1=V2), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in the other embodiments. In the following, this state is referred to as the “twelfth perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that includes a lattice portion of the first light transmitting regions  32 , in the twelfth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32 , as illustrated in  FIG. 34 . Of the light that transmits through the first light transmitting regions  32 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 , and the light near the +Z direction exits from the light ray direction controller  100 . When viewing a cross-section on a plane parallel to the XZ including the first light absorbing regions  34 , in the twelfth perpendicular narrow field mode, of the light  510  that enters from the surface light source  500 , the light near the +Z direction exits from the light ray direction controller  100 , as in the third perpendicular narrow field mode ( FIG. 21 ) of Embodiment 4. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the twelfth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 35 . 
     When viewing a cross-section on a plane parallel to the YZ plane that includes the lattice portion of the first light transmitting regions  32  and the second light transmitting regions  42 , the second light transmitting regions  42  that extend in the Y direction are positioned on the lattice that extends in the Y direction of the first light transmitting regions  32 . Accordingly, in a plane parallel to the YZ plane that includes the lattice portion of the first light transmitting regions  32  and the second light transmitting regions  42 , the emitted light of the light ray direction control element  200  in the twelfth perpendicular narrow field mode has a uniform angle distribution, as illustrated in  FIG. 36 . Meanwhile, when viewing a cross-section on a plane parallel to the YZ plane that includes the second light absorbing regions  44 , the second light absorbing regions  44  extend in the Y direction and, as such, the light  510  that enters from the surface light source  500  is absorbed by the second light absorbing regions  44 . 
     As described above, the emitted light of the light ray direction control element  200  in the twelfth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane that includes the lattice portion of the first light transmitting regions  32  and the second light transmitting regions  42 . Accordingly, in the twelfth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Thirteenth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  (V2&gt;V1), only the second light absorbing regions  44  function as light absorbing layers, as in the other embodiments. In the following, this state is referred to as the “thirteenth perpendicular narrow field mode.” 
     When viewing a cross-section on the XZ plane, in the thirteenth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  transmits through the first light transmitting regions  32  and the first light absorbing regions  34 , and of the light that transmits through the first light transmitting regions  32  and the first light absorbing regions  34 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 . Additionally, of the light that transmits through the first light transmitting regions  32  and the first light absorbing regions  34 , the light near the +Z direction exits from the light ray direction controller  100 . Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the thirteenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), as illustrated in  FIG. 35 . 
     In a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the thirteenth perpendicular narrow field mode has a uniform angle distribution, as in the twelfth perpendicular narrow field mode. 
     As described above, the emitted light of the light ray direction control element  200  in the thirteenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction) in a plane parallel to the XZ plane, and has a uniform angle distribution in a plane parallel to the YZ plane that includes the lattice portion of the first light transmitting regions  32  and the second light transmitting regions  42 . Accordingly, in the thirteenth perpendicular narrow field mode, the light ray direction control element  200  can limit the viewing angle in the left-right direction (the X direction) of the display device  300  to near the front surface (the +Z direction). 
     Fourteenth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  (V1&gt;V2), only the first light absorbing regions  34  function as light absorbing layers, as in the other embodiments. In the following, this state is referred to as the “fourteenth perpendicular narrow field mode.” 
     When viewing a cross-section on a plane parallel to the XZ plane that does not include the first light absorbing regions  34 , in the fourteenth perpendicular narrow field mode, the light  510  that enters from the surface light source  500  exits from the light ray direction control element  200  without being absorbed by the first light absorbing regions  34  and the second light absorbing regions  44 . In a plane parallel to the XZ plane that does not include the first light absorbing regions  34 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has a uniform angle distribution. 
     Additionally, when viewing a cross-section on a plane parallel to the XZ plane that includes the first light absorbing regions  34 , as illustrated in  FIG. 37 , of the light  510  that enters from the surface light source  500 , the light other than that near the +Z direction is absorbed by the second light absorbing regions  44 , and the light near the +Z direction exits from the light ray direction controller  100 . In a plane parallel to the XZ plane that includes the first light absorbing regions  34 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction). 
     Accordingly, in terms of the entire light ray direction controller  100 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has an angle distribution in which, as illustrated in  FIG. 35 , in a plane parallel to the XZ plane, the transmittance gradually decreases toward 0° and 180°, with 90° as the maximum. 
     The first light absorbing regions  34  have a quadrangular prism shape and are disposed in a matrix in the X direction and the Y direction and, as such, in a plane parallel to the YZ plane that does not include the first light absorbing regions  34 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has a uniform angle distribution. Additionally, in a plane parallel to the YZ plane that includes the first light absorbing regions  34 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction). Accordingly, in terms of the entire light ray direction controller  100 , the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has an angle distribution in which, as illustrated in  FIG. 35 , in a plane parallel to the YZ plane, the transmittance gradually decreases toward 0° and 180°, with 90° as the maximum. 
     As described above, the emitted light of the light ray direction control element  200  in the fourteenth perpendicular narrow field mode has an angle distribution in which, in a plane parallel to the XZ plane and a plane parallel to the YZ plane, the transmittance gradually decreases toward 0° and 180°, with 90° as the maximum. Accordingly, in the fourteenth perpendicular narrow field mode, the light ray direction control element  200  can narrow the viewing angle in the vertical direction and the left-right direction of the display device  300 . 
     Thirteenth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22  is greater than the potential V1 of the first light transmitting electrode  12  and the difference between the potential V2 and the potential V1 is greater than in the thirteenth perpendicular narrow field mode (V2&gt;&gt;V1), the electrophoretic particles  54  aggregate on the second light transmitting electrode  22  side of the second light absorbing regions  44 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “thirteenth wide field mode.” 
     In the thirteenth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, as illustrated in  FIGS. 35 and 36 , in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the thirteenth wide field mode has a uniform angle distribution. When viewed from above, the area of the second light absorbing regions  44  where the electrophoretic particles  54  are aggregated is great and, as such, the transmittance in the thirteenth wide field mode decreases. In the thirteenth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Fourteenth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  is greater than the potential V2 of the second light transmitting electrode  22  and the difference between the potential V1 and the potential V2 is greater than in the fourteenth perpendicular narrow field mode (V1&gt;&gt;V2), the electrophoretic particles  54  aggregate on the first light transmitting electrode  12  side of the first light absorbing regions  34 , and the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “fourteenth wide field mode.” 
     In the fourteenth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, as illustrated in  FIGS. 35 and 36 , in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the fourteenth wide field mode has a uniform angle distribution. Additionally, when viewed from above, the area of the first light absorbing regions  34  is smaller than the area of the second light absorbing regions  44  and, as such, the transmittance in the fourteenth wide field mode is higher than the transmittance in the thirteenth wide field mode. In the fourteenth wide field mode, the light ray direction control element  200  does not limit the viewing angle of the display device  300 . 
     Thus, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions by controlling the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22 . 
     Embodiment 8 
     In Embodiments 1 to 7, the first light transmitting regions  32 , the first light absorbing regions  34 , the second light transmitting regions  42 , and the second light absorbing regions  44  are sandwiched between the first light transmitting substrate  10  that includes the first light transmitting electrode  12  and the second light transmitting substrate  20  that includes the second light transmitting electrode  22 . However, a configuration is possible in which the light ray direction controller  100  is provided with a third light transmitting substrate  80  between the first light transmitting regions  32  and the first light absorbing regions  34 , and the second light transmitting regions  42  and the second light absorbing regions  44 . Here, the third light transmitting substrate  80  includes a third light transmitting electrode  82  and a fourth light transmitting electrode  84 . Aside from including the third light transmitting substrate  80 , the configuration of the light ray direction control element  200  of the present embodiment is the same as the configuration of the light ray direction control element  200  of Embodiment 1. 
     The third light transmitting substrate  80  transmits visible light. In one example, the third light transmitting substrate  80  is implemented as a light transmitting film substrate. As illustrated in  FIG. 38 , the third light transmitting substrate  80  is disposed between the first light transmitting regions  32  and the first light absorbing regions  34 , and the second light transmitting regions  42  and the second light absorbing regions  44 . The third light transmitting substrate  80  includes the third light transmitting electrode  82  on a first main surface  80   a  positioned on the first light transmitting substrate  10  side. Additionally, the third light transmitting substrate  80  includes the fourth light transmitting electrode  84  on a second main surface  80   b  positioned on the second light transmitting substrate  20  side. Accordingly, the third light transmitting electrode  82  and the fourth light transmitting electrode  84  are disposed between the first light transmitting regions  32  and the first light absorbing regions  34 , and the second light transmitting regions  42  and the second light absorbing regions  44 . In one example, the third light transmitting electrode  82  and the fourth light transmitting electrode  84  are formed from ITO. 
     In the present embodiment, the first light transmitting regions  32  and the second light transmitting regions  42 , and the first light absorbing regions  34  and the second light absorbing regions  44  are connected via the third light transmitting electrode  82 , the third light transmitting substrate  80 , and the fourth light transmitting electrode  84 . The potentials of the third light transmitting electrode  82  and the fourth light transmitting electrode  84  are controlled by the voltage controller  110 . 
     Next, the operations of the light ray direction control element  200  of the present embodiment are described. 
     Light-Blocking Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12 , the potential V2 of the second light transmitting electrode  22 , the potential V3 of the third light transmitting electrode  82 , and the potential V4 of the fourth light transmitting electrode  84  are equal (V1=V2=V3=V4), the first light absorbing regions  34  and the second light absorbing regions  44  function as light absorbing layers, as in the light-blocking mode of Embodiment 1. Accordingly, the potential V1 of the first light transmitting electrode  12 , the potential V2 of the second light transmitting electrode  22 , the potential V3 of the third light transmitting electrode  82 , and the potential V4 of the fourth light transmitting electrode  84  are equal, the light ray direction control element  200  blocks the light  510  of the surface light source  500 , as in the light-blocking mode of Embodiment 1. 
     Fifth Diagonal Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V2 of the second light transmitting electrode  22 , the potential V3 of the third light transmitting electrode  82 , and the potential V4 of the fourth light transmitting electrode  84  are equal and the potential V1 of the first light transmitting electrode  12  is less than the potentials V2 to V4 (V2=V3=V4&gt;V1), the electrophoretic particles  54  of the first light absorbing regions  34  aggregate on the third light transmitting electrode  82  side and the electrophoretic particles  54  of the second light absorbing regions  44  are uniformly dispersed as illustrated in  FIG. 39 . Accordingly, the first light absorbing regions  34  hardly function as light absorbing layers and the second light absorbing regions  44  function as light absorbing layers. In the following, this state is referred to as the “fifth diagonal narrow field mode.” 
     In the fifth diagonal narrow field mode, the first light absorbing regions  34  hardly function as light absorbing layers and the second light absorbing regions  44  function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the fifth diagonal narrow field mode has a narrow angle distribution near 90°−θ, the same as in the first diagonal narrow field mode of Embodiment 1. Additionally, in a plane parallel to a plane inclined to the +X direction side with respect to the YZ plane (0°&lt;angle of inclination&lt;2×θ), the emitted light of the light ray direction control element  200  in the fifth diagonal narrow field mode has a uniform angle distribution. 
     Fifteenth Perpendicular Narrow Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12 , the potential V3 of the third light transmitting electrode  82 , and the potential V4 of the fourth light transmitting electrode  84  are equal and the potential V2 of the second light transmitting electrode  22  is less than the potentials V1, V3, and V4 (V1=V3=V4&gt;V2), the electrophoretic particles  54  of the second light absorbing regions  44  aggregate on the fourth light transmitting electrode  84  side and the electrophoretic particles  54  of the first light absorbing regions  34  are uniformly dispersed as illustrated in  FIG. 40 . Accordingly, the second light absorbing regions  44  hardly function as light absorbing layers and the first light absorbing regions  34  function as light absorbing layers. In the following, this state is referred to as the “fifteenth perpendicular narrow field mode.” 
     In the fifteenth perpendicular narrow field mode, the second light absorbing regions  44  hardly function as light absorbing layers and the first light absorbing regions  34  function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane, the emitted light of the light ray direction control element  200  in the fifteenth perpendicular narrow field mode has a narrow angle distribution near 90° (the +Z direction), the same as in the first perpendicular narrow field mode of Embodiment 1. Additionally, in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the fifteenth perpendicular narrow field mode has a uniform angle distribution. 
     Fifteenth Wide Field Mode 
     When the voltage controller  110  performs control such that the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  are equal, and the potential V3 of the third light transmitting electrode  82  and the potential V4 of the fourth light transmitting electrode  84  are equal and greater than the potentials V1 and V2 (V1=V2&lt;V3=V4), the electrophoretic particles  54  of the first light absorbing regions  34  aggregate on the third light transmitting electrode  82  side and the electrophoretic particles  54  of the second light absorbing regions  44  aggregate on the fourth light transmitting electrode  84  side, as illustrated in  FIG. 41 . Accordingly, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. In the following, this state is referred to as the “fifteenth wide field mode.” 
     In the fifteenth wide field mode, the first light absorbing regions  34  and the second light absorbing regions  44  hardly function as light absorbing layers. Accordingly, in a plane parallel to the XZ plane and in a plane parallel to the YZ plane, the emitted light of the light ray direction control element  200  in the fifteenth wide field mode has a uniform angle distribution, the same as in the first wide field mode and the second wide field mode of Embodiment 1. 
     Thus, as with the light ray direction control element  200  of Embodiment 1, the light ray direction control element  200  of the present embodiment can emit light in three or more types of angle distributions. 
     Modified Examples 
     Embodiments have been described, but various modifications can be made to the present disclosure without departing from the spirit and scope of the present disclosure. 
     For example, a configuration is possible in which the first light transmitting substrate  10  and the second light transmitting substrate  20  are formed from a light transmitting resin. A configuration is possible in which the third light transmitting substrate  80  is implemented as a glass substrate. A configuration is possible in which the electrophoretic particles  54  are positively charged. 
     Additionally, a configuration is possible in which the first light transmitting regions  32  and the second light transmitting regions  42  are integrally formed. For example, the first light transmitting regions  32  and the second light transmitting regions  42  of Embodiment 1 may be formed as one light transmitting layer that is bent partway through. 
     The first light transmitting regions  32  of Embodiment 3 are perpendicular to the first main surface  10   a  of the first light transmitting substrate  10 . However, a configuration is possible in which the first light transmitting regions  32  of Embodiment 3 are inclined in the reverse direction of the second light transmitting regions  42  with respect to the +Z direction, as with the first light transmitting regions  32  of Embodiment 2. 
     In Embodiment 8, the third light transmitting electrode  82  and the fourth light transmitting electrode  84  are provided on the third light transmitting substrate  80 , and the third light transmitting electrode  82  and the fourth light transmitting electrode  84  are disposed between the first light transmitting regions  32  and the first light absorbing regions  34 , and the second light transmitting regions  42  and the second light absorbing regions  44 . As illustrated in  FIG. 42 , a configuration is possible in which a fifth light transmitting electrode  86  is disposed between the first light transmitting regions  32  and the first light absorbing regions  34 , and the second light transmitting regions  42  and the second light absorbing regions  44 . The fifth light transmitting electrode  86  is provided on the first main surface  80   a  and the second main surface  80   b  of the third light transmitting substrate  80 , via a through-hole. In this case, the angle distribution of the light that transmits through the light ray direction controller  100  can be controlled by controlling the potential V1 of the first light transmitting electrode  12 , the potential V2 of the second light transmitting electrode  22 , and a potential V5 of the fifth light transmitting electrode  86 . 
     For example, by making the potential V1 of the first light transmitting electrode  12 , the potential V2 of the second light transmitting electrode  22 , and the potential V5 of the fifth light transmitting electrode  86  equal, the light ray direction control element  200  can block the light  510  from the surface light source  500  (V1=V2=V5), as in the light-blocking mode of Embodiment 8. Additionally, by making the potential V1 of the first light transmitting electrode  12  and the potential V5 of the fifth light transmitting electrode  86  equal and making the potential V2 of the second light transmitting electrode  22  less than the potentials V1 and V5, the same angle distribution as in the fifth diagonal narrow field mode of Embodiment 8 can be obtained (V1=V5&gt;V2). Furthermore, by making the potential V2 of the second light transmitting electrode  22  and the potential V5 of the fifth light transmitting electrode  86  equal and making the potential V1 of the first light transmitting electrode  12  less than the potentials V2 and V5, the same angle distribution as in the fifteenth perpendicular narrow field mode of Embodiment 8 can be obtained (V1&lt;V2=V5). By making the potential V1 of the first light transmitting electrode  12  and the potential V2 of the second light transmitting electrode  22  equal and making the potential V1 and V2 less than the potential V5 of the fifth light transmitting electrode  86 , the angle distribution of the fifteenth wide field mode of Embodiment 8 can be obtained (V1=V2&lt;V5). 
     The voltage controller  110  is not limited to a control circuit. The voltage controller  110  may be configured from an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a central processing unit (CPU) and a read-only memory (ROM), or the like. 
     As illustrated in  FIG. 43 , a configuration is possible in which the display device  300  includes the light ray direction control element  200 , a transmissive liquid crystal display panel  215 , and a back light  220 . The back light  220  is disposed on the side of the transmissive liquid crystal display panel  215  opposite the display surface, and supplies light to the transmissive liquid crystal display panel  215 . The light ray direction controller  100  of the light ray direction control element  200  is disposed between the transmissive liquid crystal display panel  215  and the back light  220 , and controls the angle distribution of the light supplied from the back light  220  to the transmissive liquid crystal display panel  215 . 
     The foregoing describes some example embodiments for explanatory purposes. Although the foregoing discussion has presented specific embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the broader spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. This detailed description, therefore, is not to be taken in a limiting sense, and the scope of the invention is defined only by the included claims, along with the full range of equivalents to which such claims are entitled.