WO2021256499A1

WO2021256499A1 - Optical element, and eyewear

Info

Publication number: WO2021256499A1
Application number: PCT/JP2021/022835
Authority: WO
Inventors: 司朗七条; 孝毅高頭; 雅浩伊藤
Original assignee: 三井化学株式会社; 公立大学法人山陽小野田市立山口東京理科大学
Priority date: 2020-06-16
Filing date: 2021-06-16
Publication date: 2021-12-23
Also published as: JPWO2021256499A1

Abstract

This optical element is provided with a liquid crystal cell which includes liquid crystal molecules and a dichroic pigment, and which has a first surface and a second surface that face one another, wherein a pre-tilt angle, which is the angle of inclination of the dichroic pigment in contact with at least one surface among the first surface and the second surface, relative to said one surface, is at least equal to 5°.

Description

Optical elements and eyewear

The present invention relates to optical elements and eyewear.

Conventionally, a lens for spectacles is known as an example of an optical element (see Patent Document 1). The lens disclosed in Patent Document 1 has a lens base material and a multilayer film. Such a lens has a function of blocking light of a specific wavelength (for example, blue light) at a predetermined ratio.

Japanese Unexamined Patent Publication No. 2019-82718

By the way, when the user wears the spectacles (hereinafter referred to as the spectacles in use), if the amount of light incident on the lens from a specific direction (for example, diagonally upward) is large, it may be dazzling and the visibility may be deteriorated. There is sex. To solve this problem, if the light transmittance of the entire lens is lowered (absorption rate is increased), not only the light incident on the lens from diagonally above but also the light incident on the lens from the front is absorbed. Visibility is reduced.

An object of the present invention is to provide an optical element and eyewear capable of changing the transmittance according to the incident angle of light incident on the optical element.

One aspect of the optical element according to the present invention is
A liquid crystal cell containing a liquid crystal molecule and a dichroic dye and having a facing first surface and a second surface is provided.
The pretilt angle, which is the inclination angle of the dichroic dye in contact with at least one of the first surface and the second surface, with respect to one surface is 5 ° or more.

The eyewear according to the present invention is
An electrically active lens having the above optical element is provided.

According to the present invention, it is possible to provide an optical element and eyewear that can change the transmittance according to the incident angle of light incident on the optical element.

FIG. 1 is a schematic cross-sectional view of the optical element according to the first embodiment of the present invention in the first state. Figure 2 is an enlarged view of X ₁ part of FIG. FIG. 3 is a schematic cross-sectional view of the optical element in the second state. FIG. 4 is a diagram showing the relationship between the incident light on the optical element and the emitted light from the optical element. FIG. 5 is a schematic cross-sectional view of the optical element according to the second embodiment of the present invention in the first state. Figure 6 is an enlarged view of the X ₂ parts of FIG. FIG. 7 is a diagram showing the relationship between the incident angle, the transmittance, and the tilt angle. FIG. 8 is a schematic cross-sectional view of the optical element according to the third embodiment of the present invention in the first state. FIG. 9 is a diagram showing the relationship between the incident light on the optical element and the emitted light from the optical element. FIG. 10 is a schematic cross-sectional view of the optical element according to the fourth embodiment of the present invention in the first state. FIG. 11 is a schematic cross-sectional view of the optical element according to the fifth embodiment of the present invention in the first state. FIG. 12A is a diagram showing the relationship between the incident light on the optical element and the emitted light from the optical element. FIG. 12B is a diagram showing the relationship between the incident angle and the transmittance with respect to the embodiment according to the fifth embodiment. FIG. 13 is a schematic cross-sectional view of the optical element according to an example of the modification of the fifth embodiment in the first state. FIG. 14A is a schematic cross-sectional view of the optical element according to the sixth embodiment of the present invention in the first state. FIG. 14B is a diagram showing the relationship between the incident angle and the transmittance with respect to Examples 1, 2 and 3 according to the sixth embodiment. FIG. 14C is a diagram showing the relationship between the incident angle and the transmittance when the applied voltage is changed according to the second embodiment according to the sixth embodiment. FIG. 15 is a schematic cross-sectional view of the optical element according to an example of the modification of the sixth embodiment of the present invention in the first state. FIG. 16 is a schematic cross-sectional view of the optical element according to the seventh embodiment of the present invention. FIG. 17 is a schematic cross-sectional view of the optical element according to the eighth embodiment of the present invention. FIG. 18 is a schematic cross-sectional view of the optical element according to the ninth embodiment of the present invention. FIG. 19 is a schematic cross-sectional view of an optical element according to an example of a modification of the ninth embodiment of the present invention. FIG. 20 is a schematic cross-sectional view of the optical element according to the tenth embodiment of the present invention. FIG. 21 is a schematic cross-sectional view of an optical element according to an example of a modification of the tenth embodiment of the present invention. FIG. 22 is a schematic cross-sectional view of the optical element according to the eleventh embodiment of the present invention. FIG. 23 is a schematic cross-sectional view of the optical element according to the twelfth embodiment of the present invention. FIG. 24 is a perspective view of the electronic eyeglasses according to the thirteenth embodiment of the present invention. FIG. 25 is a front view of the lens. FIG. 26 is a sectional view taken along the line CC of FIG. 25. FIG. 27 is a schematic diagram for explaining an example of the forward tilt angle of the lens. FIG. 28 is a schematic diagram for explaining an example of the forward tilt angle of the lens. FIG. 29 is a schematic diagram of the electronic eyeglasses according to the fourteenth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The optical element and eyewear according to the embodiment described later are examples of the optical element and eyewear according to the present invention, and the present invention is not limited to the embodiment.

[Embodiment 1]
Hereinafter, the optical element 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

<Optical element>
FIG. 1 is a cross-sectional view of the optical element 1 in a state where no voltage is applied to the optical element 1. The optical element 1 changes the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 existing in the liquid crystal layer 14 according to the presence or absence of voltage application, thereby changing the first state and the second state having different optical characteristics. Switch.

The first state of the optical element 1 is a state in which no voltage is applied to the optical element 1. In the first state of the optical element 1, the liquid crystal molecules 141 and the dichroic dye 142 present in the liquid crystal layer 14 have the inclination angle of the long axis of the liquid crystal molecules 141 and the dichroic dye 142 in the thickness direction of the optical element 1. From one side (upper side in FIG. 1) to the other side (lower side in FIG. 1), the size becomes smaller (see FIG. 1).

In the first state, the optical element 1 has a property that the absorption rate (transmittance) with respect to the incident light incident on the optical element 1 is asymmetrical with the incident angle of 0 ° (hereinafter referred to as a reference incident angle) as the center (hereinafter referred to as a reference incident angle). , Called anisotropy with respect to transmittance).

On the other hand, the second state of the optical element 1 is a state in which a voltage is applied to the optical element 1. In the second state of the optical element 1, the liquid crystal molecules 141 and the dichroic dye 142 present in the liquid crystal layer 14 have the long axes of the liquid crystal molecules 141 and the dichroic dye 142 parallel to the thickness direction of the optical element 1. Become.

In the second state, the optical element 1 has a property that the absorption rate (transmittance) with respect to the incident light incident on the optical element 1 is symmetrical with the reference incident angle as the center. Therefore, the optical element 1 does not have the above-mentioned anisotropy regarding the absorptivity in the second state. Such an optical element 1 is used, for example, in a lens of spectacles or a film for a window. Hereinafter, the specific configuration and operation of the optical element 1 will be described.

In explaining the specific configuration of the optical element 1, a Cartesian coordinate system (X, Y, Z) is used for convenience of explanation. The Cartesian coordinate system (X, Y, Z) shown in each figure is a common Cartesian coordinate system. The Z direction coincides with the direction of the optical axis of the optical element 1 (hereinafter, simply referred to as "optical axis direction").

Further, in the following description, when the term "thickness direction" is used without particular notice, it means the thickness direction of the optical element 1 and each member constituting the optical element 1. The thickness direction coincides with the Z direction.

Further, the front surface (first surface) of each member means the Z direction + side (Z direction plus side) surface of each member, and the back surface (second surface) of each member is the Z direction-side of each member. It means the surface (minus side in the Z direction).

The optical element 1 has a laminated structure in which a plurality of plate-shaped or film-shaped constituent members are laminated. The stacking direction of the constituent members coincides with the Z direction.

The optical element 1 includes a first substrate 11, a first electrode 12, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, a second electrode 16, and a second substrate 17 in this order from the front surface to the back surface. Have. In the following description, the order of the description of each of the elements 11 to 17 will be changed as appropriate.

(First board and second board)
Each of the first substrate 11 and the second substrate 17 has a plate shape having transparency to visible light. The first substrate 11 and the second substrate 17 face each other at a predetermined distance in the thickness direction.

As shown in FIG. 1, the first substrate 11 and the second substrate 17 are flat plates parallel to the XY plane, respectively. However, the first substrate 11 and / or the second substrate 17 may each have a plate shape with a convex front surface and a concave back surface.

The first substrate 11 and / or the second substrate 17 are made of inorganic glass, organic glass, or the like, respectively. The first substrate 11 is preferably made of organic glass.

The organic glass is a thermosetting material made of thermosetting polyurethanes, polythiourethanes, polyepoxides, or polyepisulfides, a thermoplastic material made of poly (meth) acrylates, or a copolymer thereof. It is one of thermosetting (crosslinked) materials consisting of a mixture. However, the materials of the first substrate 11 and the second substrate 17 are not limited to these, and various known materials depending on the application can be adopted.

(1st electrode and 2nd electrode)
The first electrode 12 and the second electrode 16 are a pair of transparent electrodes having translucency. The first electrode 12 is arranged between the first substrate 11 and the first alignment film 13. The second electrode 16 is arranged between the second alignment film 15 and the second substrate 17. The liquid crystal layer 14 is sandwiched between the first electrode 12 and the second electrode 16.

The first electrode 12 and the second electrode 16 may be arranged at least within a range in which a voltage can be applied to the liquid crystal layer 14.

The materials of the first electrode 12 and the second electrode 16 are not particularly limited as long as they have the desired translucency and conductivity, respectively. Examples of the first electrode 12 and the second electrode 16 include indium tin oxide (ITO) and zinc oxide (ZnO). The materials of the first electrode 12 and the second electrode 16 may be the same or different from each other.

(First alignment film and second alignment film)
The first alignment film 13 and the second alignment film 15 each control the orientation state of the liquid crystal molecules 141 in the liquid crystal layer 14. The first alignment film 13 is arranged between the first electrode 12 and the liquid crystal layer 14. The second alignment film 15 is arranged between the liquid crystal layer 14 and the second electrode 16.

In the case of the present embodiment, the first alignment film 13 is a so-called vertical alignment film, and the long axis of the liquid crystal molecules 141 in contact with or close to the first alignment film 13 is the first surface (Z direction + side) of the liquid crystal layer 14. The orientation state of the liquid crystal molecule 141 is controlled so as to coincide with the normal direction of the surface).

The second alignment film 15 is an alignment film (also referred to as a pretilt alignment film) for imparting a pretilt angle to the liquid crystal molecules 141 in contact with or adjacent to the second alignment film 15. In the second alignment film 15, the long axis of the liquid crystal molecules 141 in contact with or close to the second alignment film 15 has a predetermined angle (pretilt described later) with respect to the second surface (Z-direction-side surface) of the liquid crystal layer 14. The orientation state of the liquid crystal molecule 141 is controlled so as to form an angle). The orientation state of the liquid crystal molecule 141 will be described later.

The first alignment film 13 and the second alignment film 15 as described above are each subjected to an orientation treatment for imparting orientation to the first alignment film 13 and the second alignment film 15, respectively. The alignment treatment is a known treatment method such as a rubbing treatment and a photo-alignment treatment.

As the material of the first alignment film 13, a known material used as the alignment film of the liquid crystal material can be used. Examples of the material of the first alignment film 13 include polyimide.

(Liquid crystal layer)
The liquid crystal layer 14 is sandwiched between the first alignment film 13 and the second alignment film 15. The liquid crystal layer 14 has a front surface defined by the back surface of the first alignment film 13 and a back surface defined by the front surface of the second alignment film 15. The liquid crystal layer 14 is surrounded by a sealing material (not shown).

The liquid crystal layer 14 is provided in a space surrounded by a sealing material between the first alignment film 13 and the second alignment film 15. Hereinafter, the direction parallel to the front surface and the back surface of the liquid crystal layer 14 is referred to as a surface direction of the liquid crystal layer 14. The liquid crystal layer 14 corresponds to an example of a liquid crystal cell. The liquid crystal layer 14, the first alignment film 13, and the second alignment film 15 may be regarded as an example of a liquid crystal cell.

The liquid crystal layer 14 switches between a first state and a second state in which the optical characteristics are different from each other depending on the presence or absence of voltage application. The first state of the liquid crystal layer 14 corresponds to the first state of the optical element 1, and is the state of the liquid crystal layer 14 when no voltage is applied to the liquid crystal layer 14. FIG. 1 shows the first state of the optical element 1 and the liquid crystal layer 14.

The second state of the liquid crystal layer 14 corresponds to the second state of the optical element 1, and is the state of the liquid crystal layer 14 when a voltage is applied to the liquid crystal layer 14. FIG. 3 shows the second state of the optical element 1 and the liquid crystal layer 14.

The liquid crystal layer 14 has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142.

The liquid crystal molecule 141 has a substantially rod shape having a major axis and a minor axis. The liquid crystal molecules 141 are present in the liquid crystal layer 14 side by side in the plane direction and the thickness direction of the liquid crystal layer 14.

The dichroic dye 142 has a substantially rod shape having a major axis and a minor axis. The shape of the dichroic dye 142 is almost the same as the shape of the liquid crystal molecule 141. The dichroic dye 142 exists in the liquid crystal layer 14 between the liquid crystal molecules 141 adjacent to each other in the plane direction and / or the thickness direction of the liquid crystal layer 14.

The dichroic dye 142 has a property that the absorption rate of light in the major axis direction of the molecule and the absorption rate of light in the minor axis direction are different. Such properties of the dichroic dye 142 realize anisotropy regarding the absorptivity of the optical element 1.

Hereinafter, the light incident on the dichroic dye 142 from the normal direction of the plane including the long axis of the dichroic dye 142 is referred to as the long axis side incident light. Further, the normal direction of the plane including the long axis of the dichroic dye 142 is referred to as a maximum absorption direction.

In the present specification, the long-axis side incident light is light that travels in a plane including the long axis of the dichroic dye 142 and is parallel to the Z direction (first plane), and has two colors. It means the light incident on the dichroic dye 142 from the direction orthogonal to the long axis of the sex dye 142. The first plane corresponds to the incident surface of the incident light on the long axis side.

Further, the light incident on the dichroic dye 142 from the direction parallel to the long axis of the dichroic dye 142 is referred to as the light incident on the short axis side. The normal direction of the plane including the minor axis of the dichroic dye 142 is referred to as the minimum absorption direction. The minimum absorption direction is also a direction parallel to the long axis of the dichroic dye 142.

As a matter of course, light other than the long-axis side incident light and the short-axis side incident light is also incident on the dichroic dye 142. The dichroic dye 142 also has a predetermined absorption rate (transmittance) for such light. However, in the following description, in order to briefly explain the characteristics of the optical element 1 of the present embodiment, the relationship between the dichroic dye 142 and the long-axis side incident light and the short-axis side incident light will be mainly referred to.

The dichroic dye 142 has a property that the absorption rate for the long-axis side incident light is larger than the absorption rate for the short-axis side incident light.

Specifically, the absorption rate of the dichroic dye 142 has the maximum absorption rate for the long-axis side incident light and the minimum absorption rate for the short-axis side incident light. That is, the dichroic dye 142 has a property that the light absorption rate differs depending on the incident direction.

Further, the dichroic dye 142 has a long axis side incident light absorption rate with respect to a so-called P wave (also referred to as a vertical vibration component of the long axis side incident light) among the components of the long axis side incident light. It has a property larger than the absorption rate of the incident light for the so-called S wave (also referred to as the horizontal vibration component of the incident light on the long axis side).

The orientation state of the liquid crystal molecule 141 is controlled by the first alignment film 13 and the second alignment film 15. The orientation state of the dichroic dye 142 is the same as the orientation state of the liquid crystal molecule 141, and changes depending on the orientation state of the liquid crystal molecule 141. Therefore, it may be considered that the alignment state of the dichroic dye 142 is also controlled by the first alignment film 13 and the second alignment film 15.

Here, a region containing the liquid crystal molecules 141 and the dichroic dye 142 in contact with the back surface of the first alignment film 13 (the front surface of the liquid crystal layer 14) and parallel to the plane direction of the liquid crystal layer 14 is the first of the liquid crystal layer 14. It is defined as a region _{R 1.}

Further, a region containing the liquid crystal molecules 141 and the dichroic dye 142 in contact with the front surface of the second alignment film 15 (the back surface of the liquid crystal layer 14) and parallel to the plane direction of the liquid crystal layer 14 is the second of the liquid crystal layer 14. It is defined as a region _{R 2.}

Further, it exists between in the thickness direction of the liquid crystal layer 14 and the first region R ₁ and the second region R _2, and defines a region parallel to the plane direction of the liquid crystal layer 14 and the intermediate region R _3. The definitions of the first region, the second region, and the intermediate region with respect to the liquid crystal layer are the same for other embodiments. Hereinafter, the first region R ₁ , the second region R ₂ , and the intermediate region R ₃ may be collectively referred to as the entire region.

Liquid crystal molecules 141 and the dichroic dye 142, from the first region R ₁ by applying to the second region R _2, are arranged adjacent in the thickness direction of the liquid crystal layer 14.

In the first state of the liquid crystal layer 14 (the state shown in FIG. 1), the liquid crystal molecules 141 and the dichroic dye 142 present in the entire region are each tilted with respect to the plane direction of the liquid crystal layer 14. The orientation state of the liquid crystal layer 14 in this embodiment is a so-called hybrid orientation.

Hereinafter, when the inclination angle of the liquid crystal molecule 141 and / or the dichroic dye 142 is referred to, it means the inclination angle of the major axis of the liquid crystal molecule 141 and / or the dichroic dye 142 with respect to the plane direction of the liquid crystal layer 14.

In the first state of the liquid crystal layer 14, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 decreases from the first region R ₁ increases toward the second region R _2. The tilt angle of the liquid crystal molecule 141 and the dichroic dye 142 is determined in relation to the incident angle of the incident light for which the absorption rate is desired to be increased.

The tilt angle of the liquid crystal molecule 141 and the dichroic dye 142 is the smaller angle (including 90 °) between the major axis of the liquid crystal molecule 141 and the surface direction of the liquid crystal layer 14.

Specifically, in a first state of the liquid crystal layer 14, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first region R ₁ is + phi _1.

In FIGS. 1 and 2, the clockwise direction is the + side with respect to the tilt angle, with the state in which the major axes of the liquid crystal molecules 141 and the dichroic dye 142 are parallel to the plane direction of the liquid crystal layer 14 as zero (reference). Called (plus side).

Further, in FIGS. 1 and 2, the direction opposite to the major axis of the liquid crystal molecule 141 and the dichroic dye 142 is referred to as a minus side (minus side) with respect to the inclination angle.

_{Hereinafter, the tilt angle + φ 1} may be referred to as the tilt angle + φ ₁ of the liquid crystal molecule 141. In the case of this embodiment, the tilt angle φ ₁ of the liquid crystal molecule 141 is + 90 °.

In the first state of the liquid crystal layer 14, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second region R ₂ is + phi _2.

Hereinafter, a tilt angle + phi _2, also referred to as pre-tilt angle + phi ₂ of the liquid crystal molecules 141. In the case of this embodiment, the absolute value of the _{pretilt angle + φ 2 is 5 °.} The absolute value of the pretilt angle + φ ₂ is preferably 5 ° or more. The absolute value of the pretilt angle phi ₂ is more preferably a 10 ° or more.

Further, in the first state of the liquid crystal layer 14, the inclination angle of the liquid crystal molecules 141 and the dichroic dye 142 existing _{in the intermediate region R 3} _{is + φ 3} . _{Hereinafter, the tilt angle + φ 3} may be referred to as the tilt angle + φ ₃ of the liquid crystal molecule 141. In the case of the liquid crystal layer 14 shown in FIG. 1, the tilt angle φ ₃ of the liquid crystal molecules 141 is + 45 °.

Incidentally, in FIG. 1, for convenience of explanation, only shows more of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region R _3. However, in the intermediate region R _3, the liquid crystal molecules 141 and the dichroic dye 142 of multiple layers in the thickness direction of the liquid crystal molecules 141 are present. The liquid crystal layer 14 is not physically divided into a plurality of layers.

The tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the intermediate region R _{3 decreases continuously from the front surface to the back surface of the liquid crystal layer 14.} _{Therefore, the tilt angle + φ 3} of the liquid crystal molecules 141 and the dichroic dye 142 existing in the intermediate region R ₃ is different for each row.

In the second state of the liquid crystal layer 14 (the state shown in FIG. 3), the entire area or an intermediate area liquid crystal molecules 141 and the dichroic in the region other than the vicinity of the boundary surface between the first region R ₁ and the second region R ₂ in R ₃ The tilt angle of the sex dye 142 is the same or almost the same.

(Summary of this embodiment)
The liquid crystal layer 14 having the above configuration switches between a first state and a second state having different optical characteristics depending on whether or not a voltage is applied. FIG. 1 shows a state (first state) of the liquid crystal layer 14 in a state where no voltage is applied.

When a voltage is applied to the liquid crystal layer 14, the state of the liquid crystal layer 14 transitions from the first state shown in FIG. 1 to the second state shown in FIG. In the second state of the liquid crystal layer 14, all the long axes of the liquid crystal molecules 141 and the dichroic dye 142 point in the same direction (in the case of this embodiment, the direction parallel to the thickness direction of the liquid crystal layer 14).

Here, the incident light incident on the optical element 1 is simply referred to as incident light L. 1 shows, by way of example, of the incident light L, incident light L ₁ from the thickness direction parallel to the direction (Z direction) of the optical element _1, tilted + theta with respect to the thickness direction of the optical element 1 The incident light L ₂ _{from the direction and the incident light L 3} from a direction tilted by −θ with respect to the thickness direction of the optical element 1 are shown. The incident light L ₂ and the incident light L ₃ have a line-symmetrical relationship with respect to the incident light L _1. The incident angle of the incident light L is an angle formed by the incident light L and the normal line of the surface (first surface) of the optical element 1. The incident angle of the incident light L is 0 ° when the incident light L and the normal line are parallel to each other.

Therefore, the incident angle of the incident light L _{1 is 0 °.} The incident angle of the incident light L _{2 is + θ.} The incident angle of the incident light L _{3 is −θ.} Although the incident light L ₁ , the incident light L ₂ , and the incident light L ₃ are shown in FIG. 1, the incident light L is incident on the optical element 1 from various angles. The angle of incidence of the incident light L on the optical element 1 may be collectively referred to as an incident angle θ.

In the following description, it is assumed that the incident light L is incident on the liquid crystal layer 14 without being refracted. Therefore, the incident light L ₁ , the incident light L ₂ , and the incident light L ₃ are incident on the liquid crystal layer 14 while maintaining the incident angle θ with respect to the optical element 1.

In FIGS. 1 and 2, the range of the incident angle θ of the incident light L is −90 ° to + 90 °. For convenience of explanation, the clockwise direction in FIGS. 1 and 2 is defined as the + side (plus side) with respect to the incident angle with respect to the incident angle of 0 °. Further, with respect to the incident angle of 0 °, the direction opposite to the clockwise direction in FIGS. 1 and 2 is defined as the − side (minus side) with respect to the incident angle.

As described above, the absorption rate of the dichroic dye 142 has the maximum absorption rate for the long-axis side incident light and the minimum absorption rate for the short-axis side incident light. Further, the dichroic dye 142 has a property that the absorption rate of the long-axis side incident light for the P wave is larger than the absorption rate of the long-axis side incident light for the S wave.

Each of the dichroic dyes 142 absorbs a P wave in the incident light L incident on the optical element 1 from the maximum absorption direction. At this time, the S wave of the incident light L incident on the optical element 1 from the maximum absorption direction is not absorbed by the dichroic dye 142 and is transmitted.

In the case of the present embodiment, as shown in FIG. 2, each of the dichroic dyes 142 is on the + side with respect to the inclination angle which is the clockwise direction with the direction parallel to the plane direction of the liquid crystal layer 14 as zero (reference). It is tilted. Therefore, as shown in FIG. 1, the maximum absorption direction of each of the dichroic dyes 142 is related to the incident angle which is a clockwise direction with respect to the incident angle of 0 ° (normal direction of the surface of the optical element 1). Included on the + side.

Therefore, the incident light L incident on the dichroic dye 142 from the maximum absorption direction (hereinafter referred to as incident light L related to the maximum absorption direction) is incident on the optical element 1 from the + side with respect to the incident angle in FIG. Light L.

_{That is, the dichroic dye 142 absorbs the P wave of the incident light L (for example, the incident light L 2 in} FIG. 1) incident on the optical element 1 from the + side with respect to the incident angle in FIG. 1, and transmits the S wave. ..

On the other hand, the incident light L incident on the dichroic dye 142 from the minimum absorption direction (hereinafter referred to as incident light L related to the minimum absorption direction) is the incident light L incident on the optical element 1 from the − side with respect to the incident angle. ..

That is, the dichroic dye 142 transmits the P wave and the S wave of _{the incident light L (for example, the incident light L 3 in} FIG. 1) incident on the optical element 1 from the − side with respect to the incident angle.

FIG. 4 exaggerates an example of the relationship between the _{P wave P 1a} and the S wave S _1a of the incident light L regarding the maximum absorption direction _{and the P wave P 2a} and the S wave S _2a of the emitted light regarding the maximum absorption direction. It is shown. The emitted light with respect to the maximum absorption direction is the emitted light emitted from the optical element 1 among the incident light L with respect to the maximum absorption direction.

The length of the arrow in FIG. 4 corresponds to the amount of light. The absorptivity a for the incident light L is obtained by the following equation 1. In formula 1, L _in is the length of the arrow of the incident light, L _out is the length of the arrow of the emitted light.

As shown in FIG. 4, since the P wave P _1a of the incident light L in the maximum absorption direction is absorbed by the dichroic dye 142, the P wave P _2a of the emitted light in the maximum absorption direction is the incident light in the maximum absorption direction. It is significantly smaller than the P wave P _{1a of L.}

_{Further, since the S wave S 1a} of the incident light L relating to the maximum absorption direction passes through the dichroic dye 142, the S wave S _2a _{of the emitted light regarding the maximum absorption direction is the S wave S 1a} of the incident light L relating to the maximum absorption direction. Is almost the same.

Further, FIG. 4 also shows an example of the relationship between the _{P wave P 1b} and the S wave S _1b in the incident light L in _{the minimum absorption direction and the P wave P 2b} and the S wave S _2b in the emitted light in the minimum absorption direction. ing. The emitted light with respect to the minimum absorption direction is the emitted light emitted from the optical element 1 among the incident light L with respect to the minimum absorption direction.

As shown in FIG. 4, since the P wave P _1b and the S wave S _1b in the incident light L in the minimum absorption direction pass through the bicolor dye 142, respectively, the P wave P _2b and S in the emitted light in the minimum absorption direction are transmitted. The wave S _2b is substantially the same as the _{P wave P 1b} and the S wave S _1b in the incident light L with respect to the minimum absorption direction.

As described above, in the case of the present embodiment, the amount of the emitted light emitted from the optical element 1 among the incident light L incident on the optical element 1 from the + side with respect to the incident angle is the optical element 1 from the − side with respect to the incident angle. Of the incident light L incident on the That is, the optical element 1 of the present embodiment has anisotropy regarding the light absorption rate in the first state.

Further, in the second state of the liquid crystal layer 14, all the long axes of the liquid crystal molecules 141 and the dichroic dye 142 point in the same direction (in the case of this embodiment, the direction parallel to the thickness direction of the liquid crystal layer 14). .. Therefore, in the second state, the optical element 1 does not have the anisotropy regarding the light absorption rate as in the first state.

As described above, the optical element 1 of the present embodiment applies a voltage between the first state having anisotropy regarding the light absorption rate and the second state having no anisotropy regarding the light absorption rate. It can be switched according to.

[Embodiment 2]
The second embodiment according to the present invention will be described with reference to FIGS. 5 to 7. FIG. 5 is a cross-sectional view showing the first state of the optical element 1B.

The optical element 1B according to the present embodiment also has anisotropy regarding the absorption rate by changing the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 present in the liquid crystal layer 14B depending on the presence or absence of voltage application. It switches between the first state and the second state, which has no anisotropy with respect to absorption.

The optical element 1B has a first substrate 11, a first electrode 12, a first alignment film 13B, a liquid crystal layer 14B, a second alignment film 15B, and a first surface in this order from the front surface (first surface) to the back surface (second surface). It has two electrodes 16 and a second substrate 17.

The structures of the first substrate 11, the first electrode 12, the second electrode 16, and the second substrate 17 are the same as those in the first embodiment. Hereinafter, the structures of the first alignment film 13B, the liquid crystal layer 14B, and the second alignment film 15B will be described.

(First alignment film and second alignment film)
The first alignment film 13B and the second alignment film 15B each control the alignment state of the liquid crystal molecules 141 in the liquid crystal layer 14B. The first alignment film 13B is arranged between the first electrode 12 and the liquid crystal layer 14B. The second alignment film 15B is arranged between the liquid crystal layer 14B and the second electrode 16.

In the case of the present embodiment, in the first alignment film 13B, the major axis direction of the liquid crystal molecules 141 in contact with or close to the first alignment film 13B is a predetermined angle with respect to the surface of the liquid crystal layer 14B (first pretilt angle described later). ), The orientation state of the liquid crystal molecule 141 is controlled.

Further, in the second alignment film 15B, the long axis direction of the liquid crystal molecules 141 in contact with or close to the second alignment film 15B forms a predetermined angle (second pretilt angle described later) with respect to the back surface of the liquid crystal layer 14B. In addition, the orientation state of the liquid crystal molecule 141 is controlled. The other structures of the first alignment film 13B and the second alignment film 15B are the same as the structures of the first alignment film 13 and the second alignment film 15 of the first embodiment.

(Liquid crystal layer)
The liquid crystal layer 14B switches between a first state and a second state in which the optical characteristics are different from each other depending on the presence or absence of voltage application. The first state of the liquid crystal layer 14B is the state of the liquid crystal layer 14B when no voltage is applied to the liquid crystal layer 14B. FIG. 5 shows the first state of the optical element 1B and the liquid crystal layer 14B.

The second state of the liquid crystal layer 14B is the state of the liquid crystal layer 14B when a voltage is applied to the liquid crystal layer 14B. Since the second state of the liquid crystal layer 14B is the same as the second state of the optical element 1 and the liquid crystal layer 14 shown in FIG. 3, the illustration is omitted.

The liquid crystal layer 14B has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142.

The shape and properties of the liquid crystal molecule 141 and the dichroic dye 142 are the same as those of the liquid crystal molecule 141 and the dichroic dye 142 of the first embodiment. In the case of the present embodiment, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the first state of the liquid crystal layer 14B is the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the first state of the liquid crystal layer 14 of the first embodiment. It is different from the orientation state.

The orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the second state of the liquid crystal layer 14B is the same as the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the second state of the liquid crystal layer 14 of the first embodiment. Is.

Also in this embodiment, in a first state of the liquid crystal layer 14B (the state shown in FIG. 5), the first region R _1, the liquid crystal molecules 141 and the dichroic present in the second region R _2, and the intermediate region R ₃ Each of the dyes 142 exists in a state of being tilted to the + side with respect to the tilt angle with respect to the plane direction of the liquid crystal layer 14B.

In the case of the present embodiment, in the first state of the liquid crystal layer 14B, the inclination angles of the liquid crystal molecules 141 and the dichroic dye 142 are all the same in all regions of the liquid crystal layer 14B.

Specifically, in a first state of the liquid crystal layer 14B, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the entire region of the liquid crystal layer 14B is a + phi _4.

In this embodiment, present in the first region R ₁ (in other words, contact with the surface of the liquid crystal layer 14B) tilt angle + phi ₄ of the liquid crystal molecules 141 and the dichroic dye 142, a first pre-tilt of the liquid crystal molecules 141 It is a horn.

Also, present in the second region R ₂ (in other words, in contact with the back surface of the liquid crystal layer 14B) tilt angle + phi ₄ of the liquid crystal molecules 141 and the dichroic dye 142 is a second pretilt angle of the liquid crystal molecules 141. In the case of this embodiment, the first pretilt angle and the second pretilt angle are equal to each other.

_{Further, the tilt angle + φ 4 of} the liquid crystal molecules 141 and the dichroic dye 142 existing in the intermediate region R ₃ is the tilt angle. In the case of the present embodiment, the first pretilt angle, the second pretilt angle, and the tilt angle of the liquid crystal molecule 141 and the dichroic dye 142 are equal.

In the case of the present embodiment, for example, the _{absolute values of the first pre-tilt angle + φ 4} , the second pre-tilt angle + φ ₄ , and the tilt angle + φ ₄ are 60 °. The absolute values of the first pre-tilt angle + φ ₄ , the second pre-tilt angle + φ ₄ , and the tilt angle + φ ₄ are preferably 40 ° or more and 70 ° or less. The absolute values of the first pre-tilt angle + φ ₄ , the second pre-tilt angle + φ ₄ , and the tilt angle + φ ₄ may be appropriately set in relation to the maximum absorption direction of the dichroic dye 142, for example.

(Summary of this embodiment)
The liquid crystal layer 14B having the above configuration switches between a first state and a second state in which the optical characteristics are different from each other depending on whether or not a voltage is applied. FIG. 5 shows the liquid crystal layer 14B in a state where no voltage is applied (first state).

When a voltage is applied to the liquid crystal layer 14B, the state of the liquid crystal layer 14B switches from the first state shown in FIG. 5 to the second state (see FIG. 3). In the second state of the liquid crystal layer 14B, the major axes of all the liquid crystal molecules 141 and the dichroic dye 142 coincide with the same direction (in the case of this embodiment, the direction parallel to the thickness direction of the liquid crystal layer 14B). ..

In the case of the present embodiment, in the first state of the liquid crystal layer 14B, the dichroic dye 142 present in the entire region of the liquid crystal layer 14B is inclined to the + side with respect to the inclination angle. Therefore, the maximum absorption direction of each of the dichroic dyes 142 is included on the + side with respect to the incident angle.

Therefore, the incident light L with respect to the maximum absorption direction is the incident light L incident on the optical element 1B from the + side with respect to the incident angle in FIG. Specifically, the incident light L on the maximum absorption direction, the angle of incidence is equal incident light L with the inclination angle + phi ₄ of the dichroic dye 142.

Therefore, the dichroic dye 142 _{absorbs the P wave of the incident light L whose incident angle is equal to + φ 4} , and transmits the S wave of the incident light L.

On the other hand, the incident light L with respect to the minimum absorption direction is the incident light L incident on the optical element 1B from the − side with respect to the incident angle in FIG. Specifically, the incident light L with respect to the minimum absorption direction is the incident light L whose incident angle is equal to −φ.

Therefore, the dichroic dye 142, the incident angle is transmitted through the P-wave and S wave equal incident light -.phi _4.

As a result, the light amount of the light beam emitted from the optical element 1B of the incident angle is equal to + phi ₄ incident light quantity of the outgoing light incident angle is emitted from the optical element 1B of equal incident light -.phi ₄ Less than. That is, the optical element 1B of the present embodiment also has anisotropy regarding the light absorption rate in the first state.

Further, in the second state of the liquid crystal layer 14B, the major axes of all the liquid crystal molecules 141 and the dichroic dye 142 face the same direction (in the case of this embodiment, the direction parallel to the thickness direction of the liquid crystal layer 14B). .. Therefore, in the second state, the optical element 1B does not have the anisotropy regarding the light absorption rate as in the first state.

As described above, the optical element 1B of the present embodiment also applies a voltage between the first state having anisotropy regarding the light absorption rate and the second state having no anisotropy regarding the light absorption rate. It can be switched according to.

In particular, in the case of the present embodiment, since the inclination angles of the dichroic dye 142 existing in the entire region of the liquid crystal layer 14B are the same, the incident light L incident on the optical element 1B from a specific direction (in the case of the present embodiment). while increasing the absorption rate of the light incident angle with respect to equal the incident light L) to + phi _4, it can be reduced absorption of light to the incident light L incident from a specific direction to the optical element 1B.

Note that FIG. 7 is a diagram showing the results of simulating the relationship between the tilt angle of the liquid crystal molecule 141 and the dichroic dye 142, the angle of incidence on the optical element 1B, and the transmittance of the optical element 1B.

When the tilt angles are 0 ° and 90 °, which correspond to the second state of the optical element 1B of the present embodiment, the transmittance with respect to the incident light incident on the optical element 1 is symmetrical with respect to the reference incident angle (0 °). become.

On the other hand, when the tilt angle is larger than 0 ° and less than 90 °, the transmittance with respect to the incident light incident on the optical element 1 becomes asymmetric around the reference incident angle (0 °). That is, the optical element 1 has anisotropy regarding the absorptivity.

According to FIG. 7, when the tilt angle corresponding to the second state of the optical element 1B is 60 °, the transmittance (0.4) for the incident light having an incident angle of 60 ° corresponding to the maximum absorption direction is the minimum absorption. It can be seen that it is smaller than the transmittance (0.7) for the incident light having an incident angle of -60 ° corresponding to the direction.

Further, when the tilt angle is 60 °, the transmittance changes linearly (decreases) from the incident angle of -30 °, which maximizes the transmittance, to the incident angle of 50 °. Such a portion contributes to the improvement of visibility because the transmittance gradually changes in the same direction.

When the dichroic dye 142 is viewed alone, the absorption rate for the incident light having an incident angle of 60 ° corresponding to the maximum absorption direction is the largest (the transmittance is the smallest), and the incident angle corresponding to the minimum absorption direction- The absorption rate for 60 ° incident light is the lowest (the transmittance is the highest). However, the relationship between the incident angle and the transmittance shown in FIG. 7 does not have such a relationship. Such a shift in relationship is due to various factors relating to elements other than the dichroic dye 142.

[Embodiment 3]
The optical element 1C according to the third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a cross-sectional view showing the first state of the optical element 1C.

The optical element 1C according to the present embodiment also has anisotropy regarding the absorption rate by changing the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 existing in the liquid crystal layer 14 depending on the presence or absence of voltage application. It switches between the first state and the second state, which has no anisotropy with respect to absorption.

The optical element 1C has a first substrate 11, a first electrode 12, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, and a first surface in this order from the front surface (first surface) to the back surface (second surface). It has two electrodes 16, a second substrate 17, and a polarizing plate 18.

The structures of the first substrate 11, the first electrode 12, the first alignment film 13, the liquid crystal layer 14, the second alignment film 15, the second electrode 16, and the second substrate 17 are the same as those in the first embodiment. Therefore, the optical element 1C of the present embodiment is composed of a first substrate 11, a first electrode 12, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, a second electrode 16, and a second substrate 17. The optical element has the same operation and effect as the optical element 1 of the first embodiment.

(Polarizer)
The polarizing plate 18 has a function of absorbing a component in the first direction of light incident on the polarizing plate 18 and transmitting a component in the second direction orthogonal to the first direction. In the case of this embodiment, the polarizing plate 18 is fixed to the back surface of the second substrate 17. However, the position of the polarizing plate 18 is not limited to the case of this embodiment.

Such a polarizing plate 18 is provided to absorb a component (S wave) that was not absorbed by the dichroic dye 142 in the incident light L (that is, the long-axis side incident light) with respect to the maximum absorption direction.

Specifically, the polarizing plate 18 has a function of transmitting a P wave in the incident light (light emitted from the second substrate 17) to the polarizing plate 18 and absorbing an S wave in the incident light on the polarizing plate 18. ..

(Summary of this embodiment)
In FIG. 9, regarding the optical element 1C of the present embodiment, the P wave and the S wave of the incident light to the optical element and the P wave and the S wave from the optical element regarding the maximum absorption direction and the minimum absorption direction in the first state of the optical element 1C are shown. An example of the relationship between the emitted light and the P wave and the S wave is exaggerated.

In FIG. 9, the incident light on the optical element is the same as the incident light on the optical element in FIG. Further, in FIG. 9, the incident light on the polarizing plate is the same as the emitted light of the optical element in FIG.

As shown in FIG. 9, the incident light incident on the polarizing plate 18 from the maximum absorption direction is such that the S wave S _2a is larger than the P wave P _2a. The polarizing plate 18 absorbs the _{S wave S 2a in the incident light.}

As a result, with respect to the maximum absorption direction, the P wave P _3a and the S wave S _{3a in the} light emitted from the polarizing plate 18 are significantly smaller than the _{P wave P 1a} and the S wave S _1b in the incident light L to the optical element 1C. Become.

The polarizing plate 18 also absorbs _{the S wave S 2b} of the incident light incident on the polarizing plate 18 from the minimum absorption direction. Therefore, with respect to the minimum absorption direction, the S wave S _{3b in the} light emitted from the polarizing plate 18 is significantly smaller than the _{S wave S 1b} in the incident light L to the optical element 1C.

[Embodiment 4]
The optical element 1D according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 10 is a cross-sectional view showing the first state of the optical element 1D.

The optical element 1D according to the present embodiment also has anisotropy regarding the absorption rate by changing the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 present in the liquid crystal layer 14B depending on the presence or absence of voltage application. It switches between the first state and the second state, which has no anisotropy with respect to absorption.

The optical element 1D has a first substrate 11, a first electrode 12, a first alignment film 13B, a liquid crystal layer 14B, a second alignment film 15B, and a first surface in this order from the front surface (first surface) to the back surface (second surface). It has two electrodes 16, a second substrate 17, and a polarizing plate 18.

The structures of the first substrate 11, the first electrode 12, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, the second electrode 16, and the second substrate 17 are the same as those in the second embodiment.

Therefore, the optical element 1D of the present embodiment is composed of the first substrate 11, the first electrode 12, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, the second electrode 16, and the second substrate 17. The optical element has the same operation and effect as the optical element 1B of the second embodiment.

Further, the polarizing plate 18 is the same as the polarizing plate 18 of the third embodiment. The optical element 1D of this embodiment as described above, in a first state of the optical element 1D, the vertical component of the incident angle θ is + phi ₄ equal incident light (i.e., light incident from the maximum absorption direction to the optical element 1D) And can absorb horizontal components.

[Embodiment 5]
The optical element 1E according to the fifth embodiment of the present invention will be described with reference to FIG. FIG. 11 is a cross-sectional view showing the first state of the optical element 1E.

The optical element 1E according to the present embodiment also has anisotropy regarding the absorption rate by changing the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 present in the liquid crystal layer 14B depending on the presence or absence of voltage application. It switches between the first state and the second state, which has no anisotropy with respect to absorption.

The optical element 1E has a first element 101e, a half-wave plate 19, and a second element 102e in this order from the front surface (first surface) to the back surface (second surface).

The first element 101e has a first substrate 11, a first electrode 12, a first alignment film 13B, a liquid crystal layer 14B, a second alignment film 15B, a second electrode 16, and a second substrate 17 in order from the front surface to the back surface. Has. The structure of the first element 101e is the same as that of the optical element 1B of the second embodiment. Therefore, the first element 101e has the same operation and effect as the optical element 1B.

Further, the second element 102e has the first substrate 11, the first electrode 12, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, the second electrode 16, and the second in order from the front surface to the back surface. It has a substrate 17. The structure of the second element 102e is also the same as that of the optical element 1B of the second embodiment. Therefore, the first element 101e has the same operation and effect as the optical element 1B.

The liquid crystal layer 14B of the first element 101e corresponds to an example of the first liquid crystal cell. Further, the liquid crystal layer 14B of the second element 102e corresponds to an example of the second liquid crystal cell.

Further, the first electrode 12 and the second electrode 16 of the first element 101e correspond to an example of a pair of first transparent electrodes. The pair of first transparent electrodes directly or indirectly sandwich the first liquid crystal cell. Further, the first electrode 12 and the second electrode 16 of the second element 102e correspond to an example of a pair of second transparent electrodes. The pair of second transparent electrodes directly or indirectly sandwich the second liquid crystal cell.

Further, the first alignment film 13B and the second alignment film 15B of the first element 101e correspond to an example of a pair of first diagonal alignment films. The pair of first diagonal alignment films directly or indirectly sandwich the first liquid crystal cell. Further, the first alignment film 13B and the second alignment film 15B of the second element 102e correspond to an example of a pair of second diagonal alignment films. The pair of second diagonally oriented films directly or indirectly sandwich the second liquid crystal cell.

The half-wave plate 19 is provided between the first element 101e and the second element 102e. The front surface of the half-wave plate 19 is fixed to the back surface of the first element 101e via the first adhesive layer 20. The back surface of the half-wave plate 19 is fixed to the surface of the second element 102e via the second adhesive layer 21.

The half-wave plate 19 has a function of generating a phase difference π (180 °) between the P wave and the S wave of the incident light and outputting the plate. Such a half-wave plate 19 converts the S wave of the incident light into a P wave and emits it.

In the case of the present embodiment, the incident light on the half-wave plate 19 is the emitted light emitted from the first element 101e.

In the case of the present embodiment, as shown in FIG. 12A, the incident light on the half-wave plate 19 with respect to the maximum absorption direction is such that the P wave P _2a is smaller than the S wave S _2a. Further, as for the light emitted from the half-wave plate 19 in relation to the maximum absorption direction, the P wave P _3a is larger than the S wave S _3a. In this way, the half-wave plate 19 converts the S wave of the incident light on the half-wave plate 19 into a P wave and emits it.

Then, when the emitted light from the half-wave plate 19 is incident on the second element 102e with respect to the maximum absorption direction, as shown in FIG. 12A, the emitted light absorbed by the second element 102e with the P wave is the second element 102e. Is emitted from.

Regarding the minimum absorption direction, as shown in FIG. 12A, the amount of light incident on the optical element 1E and the amount of light emitted from the optical element 1E are the same or almost the same.

In the case of this embodiment as well, in the first state of the optical element 1E, as in the fourth embodiment, the optical element 1E has an _{incident light having an incident angle θ equal to + φ 4} (that is, an optical element from the maximum absorption direction). It is possible to absorb the vertical component and the horizontal component of the incident light incident on 1E).

(Example according to the fifth embodiment)
Hereinafter, examples of the optical element 1F according to the fifth embodiment described above will be described.

(Manufacturing of optical elements)
First, a first substrate 11 and a second substrate 17, each of which is a glass plate having a size of 25 mm × 25 mm, were prepared. Next, the first electrode 12, which is a thin film made of ITO, was formed on the surface of the first substrate 11, and the second electrode 16, which is a thin film made of ITO, was formed on the surface of the second substrate 17.

Next, the surface of the first electrode 12 formed on the first substrate 11 is coated with a polyimide solution in which polyimide as a vertical alignment film material and polyimide as a horizontal alignment film material are mixed at a predetermined ratio. A thin film was formed. In the case of this example, 80% of the polyimide solution was used as a vertical alignment film material, and 20% of the polyimide solution was used as a horizontal alignment film material. The thickness of the first thin film was 100 nm.

Next, a second thin film was formed by applying the above-mentioned polyimide solution to the surface of the second electrode 16 formed on the second substrate 17. The thickness of the second thin film was 100 nm.

Next, the surface of the first thin film formed on the first substrate 11 was subjected to a rubbing treatment, which is an alignment treatment of the liquid crystal material, to form the first alignment film 13B. Further, the surface of the second thin film formed on the second substrate 17 was also subjected to a rubbing treatment to form the second alignment film 15. Here, it was confirmed that the pretilt angles of the first alignment film 13B and the second alignment film 15B were 25 °.

Next, the first substrate 11 and the second substrate 17 were combined so that the first alignment film 13 and the second alignment film 15 face each other. With the first substrate 11 and the second substrate 17 combined, the direction of the rubbing treatment of the first alignment film 13 and the direction of the rubbing treatment of the second alignment film 15 (hereinafter, simply referred to as the rubbing direction). Was parallel and opposite.

Next, silica spacers having a diameter of 5 μm are dispersed and arranged between the vicinity of the outer edge of the surface facing the second substrate 17 on the first substrate 11 and the vicinity of the outer edge of the surface facing the first substrate 11 on the second substrate 17. The first substrate 11 and the second substrate 17 were fixed by applying the adhesive. With the first substrate 11 and the second substrate 17 fixed, the distance between the first alignment film 13B and the second alignment film 15B was set to 5 μm.

Next, with the first substrate 11 and the second substrate 17 fixed, a liquid crystal composition was injected between the first alignment film 13B and the second alignment film 15B by utilizing the capillary phenomenon. .. As the liquid crystal composition, a liquid crystal composition in which 1 wt% of a bicolor black dye NKX-4173 (manufactured by Hayashibara Co., Ltd.) was added to the nematic liquid crystal material ZLI-4792 (manufactured by Merck) was used.

The first element 101e and the second element 102e were manufactured by the above method. Next, a cellophane adhesive tape NO.405 (manufactured by Nichiban Co., Ltd.) having a characteristic as a half-wave plate is stretched on the back surface (lower surface in FIG. 11) of the first element 101e in a stretching direction 45 with respect to the rubbing direction of the first element 101e. ° Attached so that it is tilted. This cellophane adhesive tape is the half-wave plate 19.

Then, the optical element 1E was manufactured by fixing the front surface of the second element 102e to the back surface of the first element 101e (lower surface in FIG. 11) via the cellophane adhesive tape. With the second element 102e fixed to the first element 101e, the rubbing direction of the first alignment film 13B in the first element 101e is parallel to and the same direction as the rubbing direction of the first alignment film 13B in the second element 102e. did.

Using the optical element 1E thus produced, the incident angle dependence of the transmittance in the direction parallel to the rubbing direction of the first alignment film 13B and the second alignment film 15B in the first element 101e and the second element 102e is determined. It was measured. The rubbing direction of the first element 101f and the second element 102f was set to the minus direction.

FIG. 12B shows the result of the above measurement. In FIG. 12B, the horizontal axis represents the incident angle and the vertical axis represents the transmittance. As shown in FIG. 12B, the optical element 1E is asymmetric because the transmittance for the incident light having an incident angle of −30 ° is 35% and the transmittance for the incident light having an incident angle of + 30 ° is 18%. It has an incident angle dependence of the transmittance.

Note that FIG. 13 is a diagram showing an example of a modification of the fifth embodiment. Among the optical elements 1E shown in FIG. 11, the optical element 1Eb according to this modification is the second substrate 17 of the first element 101e, the first substrate 11 of the second element 102e, the first adhesive layer 20, and the second adhesive. Layer 21 is omitted. According to the optical element 1Eb of such a modification, the number of parts is reduced, so that the manufacturing cost is low. The structure, action, and effect of the other optical elements 1Eb are the same as those of the optical element 1E.

[Embodiment 6]
The optical element 1F according to the sixth embodiment of the present invention will be described with reference to FIG. 14A. FIG. 14A is a cross-sectional view showing the first state of the optical element 1F.

The optical element 1F according to the present embodiment also has anisotropy regarding the absorption rate by changing the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 existing in the liquid crystal layer 14 depending on the presence or absence of voltage application. It switches between the first state and the second state, which has no anisotropy with respect to absorption.

The optical element 1F has a first element 101f, a half-wave plate 19, and a second element 102f in this order from the front surface (first surface) to the back surface (second surface).

The first element 101f has a first substrate 11, a first electrode 12, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, a second electrode 16, and a second substrate 17 in this order from the front surface to the back surface. Has. The structure of the first element 101f is the same as that of the optical element 1 of the first embodiment. Therefore, the first element 101f has the same operation and effect as the optical element 1.

Further, the second element 102f has a first substrate 11, a first electrode 12, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, a second electrode 16, and a second electrode in this order from the front surface to the back surface. It has a substrate 17. The structure of the second element 102e is also the same as that of the optical element 1 of the first embodiment. Therefore, the second element 102f has the same operation and effect as the optical element 1.

The half-wave plate 19 is provided between the first element 101f and the second element 102f, and is the same as the half-wave plate 19 of the optical element 1E in the fifth embodiment. The front surface of the half-wave plate 19 is fixed to the back surface of the first element 101f via the first adhesive layer 20. The back surface of the half-wave plate 19 is fixed to the surface of the second element 102f via the second adhesive layer 21.

In the case of this embodiment as well, similarly to the optical element 1E of the fifth embodiment, in the first state of the optical element 1F, the incident light L incident on the optical element 1F from the + side with respect to the incident angle in FIG. 14A (for example, not only P-wave of the incident light _{L 1)} of FIG. 14A, can absorb the S wave.

(Example 1 according to the sixth embodiment)
Hereinafter, Example 1 relating to the optical element 1F according to the above-described 6th embodiment will be described.

Next, a first thin film made of polyimide SE04811 (manufactured by Nissan Chemical Industries, Ltd.), which is a vertical alignment film material, was formed on the surface of the first electrode 12 formed on the first substrate 11. The thickness of the first thin film was 100 nm.

Further, a second thin film made of a horizontally oriented polyimide film material was formed on the surface of the second electrode 16 formed on the second substrate 17. The thickness of the second thin film was 100 nm.

Next, the surface of the first thin film formed on the first substrate 11 was subjected to a rubbing treatment, which is an alignment treatment of the liquid crystal material, to form the first alignment film 13. Further, the surface of the second thin film formed on the second substrate 17 was subjected to a rubbing treatment so that the pretilt angle of the liquid crystal molecules 141 and the dichroic dye 142 was 6 ° to form the second alignment film 15. ..

Next, silica spacers having a diameter of 5 μm are dispersed and arranged between the vicinity of the outer edge of the surface facing the second substrate 17 on the first substrate 11 and the vicinity of the outer edge of the surface facing the first substrate 11 on the second substrate 17. The first substrate 11 and the second substrate 17 were fixed by applying the adhesive. With the first substrate 11 and the second substrate 17 fixed, the distance between the first alignment film 13 and the second alignment film 15 was set to 5 μm.

Next, with the first substrate 11 and the second substrate 17 fixed, a liquid crystal composition was injected between the first alignment film 13 and the second alignment film 15 by utilizing the capillary phenomenon. .. As the liquid crystal composition, a liquid crystal composition in which 1 wt% of a bicolor black dye NKX-4173 (manufactured by Hayashibara Co., Ltd.) was added to the nematic liquid crystal material ZLI-4792 (manufactured by Merck) was used.

The first element 101f and the second element 102f were manufactured by the above method. Next, a cellophane adhesive tape NO.405 (manufactured by Nichiban Co., Ltd.) having a characteristic as a half-wave plate is placed on the back surface (lower surface in FIG. 14A) of the first element 101f in a stretching direction 45 with respect to the rubbing direction of the first element 101f. ° Attached so that it is tilted. This cellophane adhesive tape is the half-wave plate 19.

Then, the optical element 1F was manufactured by fixing the front surface of the second element 102f to the back surface of the first element 101f (lower surface in FIG. 14A) via the cellophane adhesive tape. With the second element 102f fixed to the first element 101f, the rubbing direction of the first alignment film 13 in the first element 101f is parallel to and in the same direction as the rubbing direction of the first alignment film 13 in the second element 102f. be.

Using the optical element 1F thus produced, the incident angle dependence of the transmittance in the direction parallel to the rubbing direction of the first alignment film 13 and the second alignment film 15 in the first element 101f and the second element 102f is determined. It was measured (hereinafter, this measurement is referred to as measurement 1). The rubbing direction of the first element 101f and the second element 102f is set to the minus direction.

FIG. 14B shows the result of the above measurement 1. In FIG. 14B, the horizontal axis represents the incident angle and the vertical axis represents the transmittance. As shown in FIG. 14B, the optical element 1F is asymmetric because the transmittance for the incident light having an incident angle of −45 ° is 35% and the transmittance for the incident light having an incident angle of + 45 ° is 20%. It has an incident angle dependence of the transmittance.

(Example 2 according to the sixth embodiment)
Next, Example 2 regarding the optical element 1F according to the sixth embodiment will be described.

(Manufacturing of optical elements)
The optical element 1F was produced by the same method as in Example 1 described above, except that the concentration of the dichroic dye with respect to the liquid crystal composition ZLI-4792 was set to 3 wt%. Then, using the optical element 1F, the incident angle dependence of the transmittance in the direction parallel to the rubbing direction of the first alignment film 13 and the second alignment film 15 in the first element 101f and the second element 102f was measured (hereinafter,). , This measurement is referred to as measurement 2-1).

FIG. 14B shows the result of the above measurement 2-1. As shown in FIG. 14B, the transmittance for incident light having an incident angle of −45 ° is 19%, and the transmittance for incident light having an incident angle of + 45 ° is 6%. Therefore, the optical element 1F of this example also has a transmittance of 6%. , Has an asymmetric transmittance incident angle dependence.

Further, when the applied voltage applied to the optical element 1F of this example is 0V, 1V, 3V, 5V, 10V, the first alignment film 13 and the second alignment film 15 in the first element 101f and the second element 102f The incident angle dependence of the transmittance in the direction parallel to the rubbing direction was measured (hereinafter, this measurement is referred to as measurement 2-2). FIG. 14C shows the result of the above measurement 2-2. By applying a voltage, the incident angle dependence of the transmittance in the optical element 1F disappears, and the asymmetry is lost.

(Example 3 according to the sixth embodiment)
Next, Example 3 regarding the optical element 1F according to the sixth embodiment will be described.

(Manufacturing of optical elements)
The optical element 1F was produced by the same method as in Example 1 described above, except that the concentration of the dichroic dye with respect to the liquid crystal composition ZLI-4792 was set to 5 wt%. Then, using the optical element 1F, the incident angle dependence of the transmittance in the direction parallel to the rubbing direction of the first alignment film 13 and the second alignment film 15 in the first element 101f and the second element 102f was measured (hereinafter,). , This measurement is referred to as measurement 3).

FIG. 14B shows the result of the above measurement 3. As shown in FIG. 14B, the transmittance for incident light having an incident angle of −45 ° is 7%, and the transmittance for incident light having an incident angle of + 45 ° is 1%. Therefore, the optical element 1F of this example also has a transmittance of 1%. , Has an asymmetric transmittance incident angle dependence.

Note that FIG. 15 is a diagram showing an example of a modification of the sixth embodiment. Among the optical elements 1F shown in FIG. 14A, the optical element 1Fb according to this modification is the second substrate 17 of the first element 101f, the first substrate 11 of the second element 102f, the first adhesive layer 20, and the second adhesive. Layer 21 is omitted. According to the optical element 1Fb of such a modification, the number of parts is reduced, so that the manufacturing cost is low. The structure, action, and effect of the other optical elements 1Fb are the same as those of the optical element 1F.

[Embodiment 7]
The optical element 1G according to the seventh embodiment of the present invention will be described with reference to FIG. FIG. 16 is a cross-sectional view of the optical element 1G.

In the case of the present embodiment, the optical element 1G does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the liquid crystal layer 14 of the optical element 1G is always in the same orientation state.

The optical element 1G has a structure in which the first electrode 12 and the second electrode 16 are omitted from the optical element 1 of the first embodiment. Specifically, the optical element 1G has a first substrate 11, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, and a second substrate 17 in this order from the front surface to the back surface.

The first substrate 11, the first alignment film 13, the liquid crystal layer 14, the second alignment film 15, and the second substrate 17 of the optical element 1G are the first substrate 11, the first alignment film 13 in the optical element 1 of the first embodiment. , The liquid crystal layer 14, the second alignment film 15, and the second substrate 17.

The orientation state of the liquid crystal layer 14 in the optical element 1G having the above configuration is the same as the orientation state of the liquid crystal layer 14 in the first state of the optical element 1 of the first embodiment. Therefore, the optical element 1G has the same operation and effect as the first state of the optical element 1 of the first embodiment.

[Embodiment 8]
The optical element 1H according to the eighth embodiment of the present invention will be described with reference to FIG. FIG. 17 is a cross-sectional view of the optical element 1H.

In the case of the present embodiment, the optical element 1H does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the liquid crystal layer 14B of the optical element 1H is always in the same orientation state.

The optical element 1H has a structure in which the first electrode 12 and the second electrode 16 are omitted from the optical element 1B of the second embodiment. Specifically, the optical element 1H has the first substrate 11, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the like in order from the front surface (first surface) to the back surface (second surface). It has a second substrate 17.

The first substrate 11, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17 of the optical element 1H are the first substrate 11, the first alignment film 13B in the optical element 1B of the second embodiment. , The liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17.

The orientation state of the liquid crystal layer 14B of the optical element 1H having the above configuration is the same as the orientation state of the liquid crystal layer 14B in the first state of the optical element 1B of the second embodiment. Therefore, the optical element 1H has the same operation and effect as the first state of the optical element 1B of the second embodiment.

[Embodiment 9]
The optical element 1J according to the ninth embodiment of the present invention will be described with reference to FIG. FIG. 18 is a cross-sectional view of the optical element 1J.

In the case of this embodiment, the optical element 1J does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the liquid crystal layer 14B of the optical element 1J is always in the same orientation state.

The optical element 1J has a structure in which the first electrode 12 and the second electrode 16 are omitted from each of the first element 101e and the second element 102e in the optical element 1E of the fifth embodiment.

Specifically, the optical element 1J has a first element 101j, a half-wave plate 19, and a second element 102j in this order from the front surface (first surface) to the back surface (second surface).

The first element 101j has a first substrate 11, a first alignment film 13B, a liquid crystal layer 14B, a second alignment film 15B, and a second substrate 17 in this order from the front surface to the back surface.

The first substrate 11, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17 of the first element 101j are the first substrate 11, the first orientation of the first element 101e in the fifth embodiment. This is the same as the film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17.

The orientation state of the liquid crystal layer 14B in the first element 101j is always the same as the orientation state of the liquid crystal layer 14B in the first state of the first element 101e of the fifth embodiment. Therefore, the first element 101j has the same operation and effect as the first state of the first element 101e of the fifth embodiment.

Further, the second element 102j has a first substrate 11, a first alignment film 13B, a liquid crystal layer 14B, a second alignment film 15B, and a second substrate 17 in this order from the front surface to the back surface.

The first substrate 11, the first alignment film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17 of the second element 102j are the first substrate 11, the first orientation of the second element 102e in the fifth embodiment. This is the same as the film 13B, the liquid crystal layer 14B, the second alignment film 15B, and the second substrate 17.

The orientation state of the liquid crystal layer 14B in the second element 102j is always the same as the orientation state of the liquid crystal layer 14B in the first state of the second element 102e of the fifth embodiment. Therefore, the second element 102j has the same operation and effect as the first state of the second element 102e of the fifth embodiment.

The half-wave plate 19 is the same as the half-wave plate 19 of the optical element 1E in the fifth embodiment.

The orientation state of the liquid crystal layer 14B in the optical element 1J having the above configuration is the same as the orientation state of the liquid crystal layer 14B in the first state of the optical element 1E according to the fifth embodiment. Therefore, the optical element 1J has the same operation and effect as the first state of the optical element 1E of the fifth embodiment.

Note that FIG. 19 is a diagram showing an example of a modification of the ninth embodiment. Among the optical elements 1J shown in FIG. 18, the optical element 1Jb according to this modification is the second substrate 17 of the first element 101j, the first substrate 11 of the second element 102j, the first adhesive layer 20, and the second adhesive. Layer 21 is omitted. According to the optical element 1Jb of such a modification, the number of parts is reduced, so that the manufacturing cost is low. The structure, action, and effect of the other optical elements 1Jb are the same as those of the optical element 1J.

[Embodiment 10]
The optical element 1K according to the tenth embodiment of the present invention will be described with reference to FIG. 20. FIG. 20 is a cross-sectional view of the optical element 1K.

In the case of this embodiment, the optical element 1K does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the liquid crystal layer 14 of the optical element 1K is always in the same orientation state.

The optical element 1K has a structure in which the first electrode 12 and the second electrode 16 are omitted from each of the first element 101f and the second element 102f in the optical element 1F of the sixth embodiment.

Specifically, the optical element 1K has a first element 101k, a half-wave plate 19, and a second element 102k in order from the front surface (first surface) to the back surface (second surface).

The first element 101k has a first substrate 11, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, and a second substrate 17 in this order from the front surface to the back surface.

The first substrate 11, the first alignment film 13, the liquid crystal layer 14, the second alignment film 15, and the second substrate 17 of the first element 101k are the first substrate 11, the first orientation of the first element 101f in the sixth embodiment. This is the same as the film 13, the liquid crystal layer 14, the second alignment film 15, and the second substrate 17.

The orientation state of the liquid crystal layer 14 in the first element 101k is always the same as the orientation state of the liquid crystal layer 14 in the first state of the first element 101f of the sixth embodiment. Therefore, the first element 101k has the same operation and effect as the first state of the first element 101f of the sixth embodiment.

Further, the second element 102k has a first substrate 11, a first alignment film 13, a liquid crystal layer 14, a second alignment film 15, and a second substrate 17 in this order from the front surface to the back surface.

The first substrate 11, the first alignment film 13, the liquid crystal layer 14, the second alignment film 15, and the second substrate 17 of the second element 102k are the first substrate 11, the first orientation of the second element 102f in the sixth embodiment. This is the same as the film 13, the liquid crystal layer 14, the second alignment film 15, and the second substrate 17.

The orientation state of the liquid crystal layer 14 in the second element 102k is always the same as the orientation state of the liquid crystal layer 14 in the first state of the second element 102k of the sixth embodiment. Therefore, the second element 102k has the same operation and effect as the first state of the second element 102f of the 68th embodiment.

The half-wave plate 19 is the same as the half-wave plate 19 of the optical element 1F in the sixth embodiment.

The orientation state of the liquid crystal layer 14 in the optical element 1K having the above configuration is the same as the orientation state of the liquid crystal layer 14 in the first state of the optical element 1F according to the sixth embodiment. Therefore, the optical element 1K has the same operation and effect as the first state of the optical element 1F of the fifth embodiment.

Note that FIG. 21 is a diagram showing an example of a modification of the tenth embodiment. In the optical element 1Kb according to this modification, among the optical elements 1K shown in FIG. 20, the second substrate 17 of the first element 101k and the first substrate 11 of the second element 102k are omitted. According to the optical element 1Kb of such a modification, the number of parts is reduced, so that the manufacturing cost is low. The structure, action, and effect of the other optical elements 1Kb are the same as those of the optical element 1K.

[Embodiment 11]
The optical element 1L according to the eleventh embodiment of the present invention will be described with reference to FIG. 22. FIG. 22 is a cross-sectional view of the optical element 1L.

In the case of this embodiment, the optical element 1L does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the first liquid crystal layer 14L1 and the second liquid crystal layer 14L2 of the optical element 1L are always in the same orientation state.

The optical element 1L has a first substrate 11, a first alignment film 13L, a first liquid crystal layer 14L1, a half-wave plate 19, and a second liquid crystal layer 14L2 in order from the front surface (first surface) to the back surface (second surface). , A second alignment film 15L, and a second substrate 17.

The first substrate 11 and the second substrate 17 of the optical element 1L are the same as those in the first embodiment.

(First alignment film and second alignment film)
The first alignment film 13L is a so-called horizontal alignment film, so that the major axis of the liquid crystal molecules 141 in contact with or adjacent to the first alignment film 13L is parallel to or substantially parallel to the surface of the first liquid crystal layer 14L1. , Controls the orientation state of the liquid crystal molecule 141.

The second alignment film 15L is a so-called horizontal alignment film, so that the major axis of the liquid crystal molecules 141 in contact with or adjacent to the second alignment film 15L is parallel to or substantially parallel to the back surface of the second liquid crystal layer 14L2. , Controls the orientation state of the liquid crystal molecule 141.

(First liquid crystal layer and second liquid crystal layer)
The first liquid crystal layer 14L1 has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142. The shape and properties of the liquid crystal molecule 141 and the dichroic dye 142 are the same as those of the liquid crystal molecule 141 and the dichroic dye 142 of the first embodiment.

In the case of the present embodiment, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the first liquid crystal layer 14L1 does not always change.

The liquid crystal molecules 141 and the dichroic dye 142 present in the entire region of the first liquid crystal layer 14L1 each exist in a state of being inclined with respect to the plane direction of the first liquid crystal layer 14L1.

In this embodiment, in the first liquid crystal layer 14L1, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is continuously increased from the first region R ₁ increases toward the second region R _2. In other words, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first liquid crystal layer 14L1 approaches 90 ° toward the half-wave plate 19 described later.

Specifically, the inclination angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first region _{R 1} of the first liquid crystal layer 14L1 is + theta _1.

Hereinafter, the tilt angle + φ ₁ may be referred to as the pre-tilt angle + φ _{1 of the first liquid crystal layer 14L1.} In the case of this embodiment, the absolute value of the _{pretilt angle + φ 1 is 5 °.} The absolute value of the pretilt angle + φ ₁ is preferably 5 ° or more. The absolute value of the pretilt angle φ ₁ is more preferably 10 ° or more.

The tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second region _{R 2} of the first liquid crystal layer 14L1 is + phi _2.

Hereinafter, the inclination angle + phi _2, also referred to as a tilt angle + phi ₂ of the first liquid crystal layer 14L1. In this embodiment, the tilt angle phi ₂ is + 90 °.

Generally, it is known that at the air interface where the liquid crystal is in contact with air, the liquid crystal molecules 141 have the property of spontaneously arranging in the 90 ° direction with respect to the interface. Utilizing such a property, it is possible to orient the pretilt angle of the liquid crystal molecule 141 in the second region R2 to 90 ° in the absence of the vertical alignment film.

Further, by using a liquid crystal molecule having a polymerizable group as the liquid crystal molecule 141 and polymerizing after forming the hybrid orientation as described above, the liquid crystal molecule 141 and the dichroic dye 142 are solidified or filmed while preserving the state. It is possible to make it.

Further, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} of the first liquid crystal layer 14L1 is + phi _3.

Hereinafter, the inclination angle + phi _3, also referred to as a tilt angle + phi ₃ of the first liquid crystal layer 14L1. If the first liquid crystal layer 14L1 of FIG. 22, the tilt angle phi ₃ is a + 45 °.

The second liquid crystal layer 14L2 has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142. The shape and properties of the liquid crystal molecule 141 and the dichroic dye 142 are the same as those of the liquid crystal molecule 141 and the dichroic dye 142 of the first embodiment.

In the case of this embodiment, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the second liquid crystal layer 14L2 does not always change.

The liquid crystal molecules 141 and the dichroic dye 142 present in the entire region of the second liquid crystal layer 14L2 each exist in a state of being tilted with respect to the plane direction of the second liquid crystal layer 14L2.

In this embodiment, in the second liquid crystal layer 14L2, the inclination angle of the major axis of the liquid crystal molecules 141 and the dichroic dye 142 decreases from the first region R ₁ increases toward the second region R _2. In other words, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second liquid crystal layer 14L2 approaches 90 ° toward the half-wave plate 19.

Specifically, the inclination angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first region _{R 1} of the second liquid crystal layer 14L2 is + phi _1.

Hereinafter, the inclination angle + phi _1, also referred to as a tilt angle + phi ₁ of the second liquid crystal layer 14L2. In the case of this embodiment, the tilt angle φ ₁ is + 90 °.

The tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second region _{R 2} of the second liquid crystal layer 14L2 is + phi _2.

Hereinafter, the inclination angle + φ ₂ may be referred to as _{the pretilt angle + φ 2 of} the liquid crystal molecule 141 and the dichroic dye 142 present in the second region R _2. In the case of this embodiment, the absolute value of the _{pretilt angle + φ 2 is 5 °.} The absolute value of the pretilt angle + φ ₂ is preferably 5 ° or more. The absolute value of the pretilt angle phi ₂ is more preferably a 10 ° or more.

Further, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} of the second liquid crystal layer 14L2 is + phi _3.

Hereinafter, the inclination angle + phi _3, also referred to as a tilt angle + phi ₃ of the second liquid crystal layer 14L2. If the second liquid crystal layer 14L2 of FIG. 22, the tilt angle phi ₃ of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} is + 45 °.

(Half-wave plate)
The half-wave plate 19 is provided between the first liquid crystal layer 14L1 and the second liquid crystal layer 14L2. The front surface of the half-wave plate 19 is fixed to the back surface of the first liquid crystal layer 14L1 via the first adhesive layer 20.

The back surface of the half-wave plate 19 is fixed to the surface of the second liquid crystal layer 14L2 via the second adhesive layer 21. The configuration of the other half-wave plate 19 is the same as the configuration of the half-wave plate 19 of the fifth embodiment.

The action and effect of the optical element 1L having the above configuration is the same as the action and effect of the optical element 1F of the sixth embodiment. According to the optical element 1L of the present embodiment as described above, the number of parts is reduced, so that the manufacturing cost is low.

[Embodiment 12]
The optical element 1M according to the twelfth embodiment of the present invention will be described with reference to FIG. 23. FIG. 23 is a cross-sectional view of the optical element 1M.

In the case of this embodiment, the optical element 1M does not have a function of switching the state depending on whether or not a voltage is applied. Therefore, the first liquid crystal layer 14M1 and the second liquid crystal layer 14M2 of the optical element 1M are always in the same orientation state.

The optical element 1M has a first liquid crystal layer 14L1, a first alignment film 13M, a half-wave plate 19, a second alignment film 15M, and a second liquid crystal in order from the front surface (first surface) to the back surface (second surface). It has a layer 14L2.

(First alignment film and second alignment film)
The first alignment film 13M is fixed to the back surface of the first liquid crystal layer 14M1. The first alignment film 13M is a so-called horizontal alignment film, and the major axis of the liquid crystal molecule 141 in contact with or in the vicinity of the first alignment film 13M is parallel to or substantially parallel to the back surface of the first liquid crystal layer 14M1. , The orientation state of the liquid crystal molecule 141 in the first liquid crystal layer 14L1 is controlled.

The second alignment film 15M is fixed to the surface of the second liquid crystal layer 14M2. The second alignment film 15M is a so-called horizontal alignment film, so that the major axis of the liquid crystal molecules 141 in contact with or adjacent to the second alignment film 15M is parallel to or substantially parallel to the surface of the second liquid crystal layer 14M2. , The orientation state of the liquid crystal molecule 141 in the second liquid crystal layer 14M2 is controlled.

(First liquid crystal layer and second liquid crystal layer)
The first liquid crystal layer 14M1 has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142. The shape and properties of the liquid crystal molecule 141 and the dichroic dye 142 are the same as those of the liquid crystal molecule 141 and the dichroic dye 142 of the first embodiment.

In the case of this embodiment, the surface (first surface) of the first liquid crystal layer 14M1 is not fixed to other members. In other words, the surface of the first liquid crystal layer 14M1 is exposed to the outside in a state of being exposed to the outside air.

In the case of this embodiment, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the first liquid crystal layer 14M1 does not change at all times.

The liquid crystal molecules 141 and the dichroic dye 142 present in the entire region of the first liquid crystal layer 14M1 each exist in a state of being tilted with respect to the plane direction of the first liquid crystal layer 14M1.

In this embodiment, in the first liquid crystal layer 14M1, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142, from the first region R ₁ increases toward the second region R _2, successively smaller. In other words, the tilt angle of the liquid crystal molecule 141 and the dichroic dye 142 approaches 90 ° toward the surface of the first liquid crystal layer 14M1 (that is, the boundary between the first liquid crystal layer 14M1 and the outside air).

Specifically, the inclination angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first region _{R 1} of the first liquid crystal layer 14M1 is + phi _1.

Hereinafter, the inclination angle + phi _1, also referred to as a tilt angle + phi ₁ of the first liquid crystal layer 14M1. In the case of this embodiment, the tilt angle φ ₁ is + 90 °.

The tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second region _{R 2} of the first liquid crystal layer 14M1 is + phi _2.

In the case of this embodiment, the tilt angle + φ ₂ is the pretilt angle. In the case of this embodiment, the absolute value of the _{pretilt angle + φ 2 is 5 °.} The absolute value of the pretilt angle + φ ₂ is preferably 5 ° or more. The absolute value of the pretilt angle phi ₂ is more preferably a 10 ° or more.

Further, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} of the first liquid crystal layer 14M1 is + phi _3.

Hereinafter, the inclination angle + φ ₃ may be referred to as a _{tilt angle + φ 3 of} the liquid crystal molecule 141 and the dichroic dye 142 existing in the intermediate region R _3. In this embodiment, the tilt angle phi ₃ is a + 45 °.

The second liquid crystal layer 14M2 has a plurality of liquid crystal molecules 141 and a plurality of dichroic dyes 142. The shape and properties of the liquid crystal molecule 141 and the dichroic dye 142 are the same as those of the liquid crystal molecule 141 and the dichroic dye 142 of the first embodiment.

In the case of this embodiment, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the second liquid crystal layer 14M2 does not always change.

The liquid crystal molecules 141 and the dichroic dye 142 present in the entire region of the second liquid crystal layer 14M2 each exist in a state of being tilted with respect to the plane direction of the second liquid crystal layer 14M2.

In this embodiment, in the second liquid crystal layer 14M2, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is increased from the first region R ₁ increases toward the second region R _2. In other words, the inclination angle of the liquid crystal molecule 141 and the dichroic dye 142 approaches 90 ° toward the back surface of the second liquid crystal layer 14M2 (that is, the boundary between the second liquid crystal layer 14M2 and the outside air).

Specifically, the inclination angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the first region _{R 1} of the second liquid crystal layer 14M2 is + phi _1.

In the case of this embodiment, the inclination angle + φ ₁ is the pretilt angle. In the case of this embodiment, the absolute value of the _{pretilt angle + φ 1 is 5 °.} The absolute value of the pretilt angle + φ ₁ is preferably 5 ° or more. The absolute value of the pretilt angle φ ₁ is more preferably 10 ° or more.

The tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 present in the second region _{R 2} of the second liquid crystal layer 14M2 is + phi _2. Hereinafter, the inclination angle + phi _2, also referred to as a tilt angle + phi ₂ of the second liquid crystal layer 14M2. In this embodiment, the tilt angle phi ₂ is + 90 °.

Further, the tilt angle of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} of the second liquid crystal layer 14M2 is + phi _3.

Hereinafter, the inclination angle + φ ₃ may be referred to as a _{tilt angle + φ 3 of} the liquid crystal molecule 141 and the dichroic dye 142 existing in the intermediate region R _3. If the second liquid crystal layer 14M2 shown in FIG. 23, the tilt angle phi ₃ of the liquid crystal molecules 141 and the dichroic dye 142 is present in the intermediate region _{R 3} is + 45 °.

(Half-wave plate)
The half-wave plate 19 is provided between the first alignment film 13M and the second alignment film 15M. The configuration of the other half-wave plate 19 is the same as the configuration of the half-wave plate 19 of the fifth embodiment.

The action and effect of the optical element 1M having the above configuration is the same as the action and effect of the optical element 1F of the sixth embodiment. According to the optical element 1L of the present embodiment as described above, the number of parts is reduced, so that the manufacturing cost is low.

[Embodiment 13]
The electronic eyeglasses 5 according to the thirteenth embodiment of the present invention will be described with reference to FIGS. 24 to 28. FIG. 24 is a perspective view showing an example of the configuration of the electronic eyeglasses 5. FIG. 25 is a front view of the lens 51. FIG. 26 is a sectional view taken along the line CC of FIG. 25.

The electronic eyeglasses 5 have a frame 50, a pair of lenses 51,

control units

55a and 55b,

detection units

54a and 54b, and

power supplies

56a and 56b.

(flame)
The frame 50 has a front 501 and a pair of

temples

502a, 502b. Hereinafter, the portion where the front 501 is arranged is referred to as the front (front) of the electronic glasses 5.

The front end (first end) of each of the pair of

temples

502a and 502b is supported by the front 501. The pair of

temples

502a and 502b hold

detection units

54a and 54b,

control units

55a and 55b, and

power supplies

56a and 56b, respectively.

The user (wearer) of the electronic eyeglasses 5 operates (for example, a touch operation) the detection unit 54a provided on one of the temples 502a to obtain the optical characteristics (for example, transmittance) of the first optical element 52 in the lens 51. ) Is switched.

When the detection unit 54a is operated by the user, the control unit 55a switches between a state in which a voltage is applied to the first optical element 52 and a state in which a voltage is not applied, based on the operation.

Further, the user (wearer) of the electronic eyeglasses 5 operates (for example, a touch operation) the detection unit 54b provided on the other temple 502b to obtain the optical characteristics (for example, for example) of the second optical element 53 of the lens 51. Transparency) is switched. In the case of the present embodiment, the second optical element 53 is the optical element 1B of the second embodiment described above. The second optical element 53 is provided on the upper surface (Z direction + side) of the first optical element 52.

(lens)
Hereinafter, in explaining the configuration of the lens 51, the Cartesian coordinate system (X, Y, Z) shown in FIGS. 25 to 26 will be used for convenience of explanation. The Cartesian coordinate system (X, Y, Z) shown in FIGS. 25 to 26 corresponds to the Cartesian coordinate system (X, Y, Z) shown in each figure used in the description of the first to twelfth embodiments. ing.

In the case of this embodiment, the lens 51 is curved in a convex shape toward the + side in the Z direction. However, in FIG. 26, the curvature of the lens 51 is shown as zero.

The pair of lenses 51 are formed so as to be symmetrical when the electronic spectacles 5 are viewed from the front, and have the same components as each other. Therefore, in the following description, the lens 51 for the right eye of the electronic eyeglasses 5 will be described, and the description of the lens 51 for the left eye will be omitted.

The lens 51 corresponds to an example of an electrically active lens whose state changes according to the application of a voltage, and has a first optical element 52 and a second optical element 53. The first optical element 52 and the second optical element 53 are laminated in the Z direction.

(First optical element)
The first optical element 52 has a liquid crystal lens unit 521 and a normal lens unit 522 which is a portion other than the liquid crystal lens unit 521.

(LCD lens part)
The focal length (power) of the liquid crystal lens unit 521 can be switched by a voltage. As shown in FIG. 26, the liquid crystal lens unit 521 includes a first substrate 523, a first electrode 524, a liquid crystal layer 525, a second electrode 526, and a second substrate 527 in this order from the rear side (Z direction − side). Have. The first electrode 524, the liquid crystal layer 525, and the second electrode 526 constitute an electric element.

(Normal lens part)
The normal lens portion 522 has a first substrate 523, a first electrode 524, an adhesive layer 528, a second electrode 526, and a second substrate 527 in this order from the rear side. The liquid crystal lens unit 521 and the normal lens unit 522 share a first substrate 523, a first electrode 524, a second electrode 526, and a second substrate 527. The components of the liquid crystal lens unit 521 and the normal lens unit 522 each have translucency with respect to visible light.

(First board)
The first substrate 523 has a plate shape that curves convexly toward the + side in the Z direction (upper side in FIG. 26). The surface of the first substrate 523 (the surface on the + side in the Z direction) is a convex curved surface that curves convexly toward the + side in the Z direction. Further, the back surface (the surface on the Z direction − side) of the first substrate 523 is a concave curved surface that curves concavely toward the + side in the Z direction.

The first substrate 523 has a diffraction region 523a in a portion of the surface corresponding to the liquid crystal lens portion 521. The diffraction region 523a has a hemispherical convex portion 523b arranged in the central portion and a plurality of annular first convex portions 523c arranged on a concentric circle centered on the convex portion 523b.

An example of the shape of the convex portion 523b and the first convex strip 523c is a Fresnel lens shape. A part of the convex portion 523b and the first convex strip 523c may have a Fresnel lens shape, or all of them may have a Fresnel lens shape.

The first substrate 523 is made of inorganic glass or organic glass. The first substrate 523 is preferably made of organic glass. The organic glass is a thermosetting material made of thermosetting polyurethanes, polythiourethanes, polyepoxides, or polyepisulfides, a thermoplastic material made of poly (meth) acrylates, or a copolymer thereof. It is one of thermosetting (crosslinked) materials consisting of a mixture. However, the material of the first substrate 523 is not limited to these, and a known material used as a lens material can be adopted.

(1st electrode and 2nd electrode)
The first electrode 524 and the second electrode 526 are a pair of transparent electrodes having translucency. The first electrode 524 is arranged between the first substrate 523 and the liquid crystal layer 525. The second electrode 526 is arranged between the liquid crystal layer 525 and the second substrate 527.

The first electrode 524 and the second electrode 526 may be arranged at least over a range in which a voltage can be applied to the liquid crystal layer 525 (liquid crystal lens portion 521).

The materials of the first electrode 524 and the second electrode 526 are not particularly limited as long as they have the desired translucency and conductivity. Examples of the first electrode 524 and the second electrode 526 include indium tin oxide (ITO) and zinc oxide (ZnO). The materials of the first electrode 524 and the second electrode 526 may be the same as or different from each other.

(Liquid crystal layer)
The liquid crystal layer 525 is arranged between the first electrode 524 and the second electrode 526. The liquid crystal layer 525 is configured so that its refractive index changes depending on the presence or absence of application of a voltage.

The refractive index of the liquid crystal layer 525 is substantially the same as the refractive index of the first substrate 523 and the refractive index of the second substrate 527 in a state where no voltage is applied to the liquid crystal layer 525 (also referred to as the first state of the liquid crystal layer 525). Adjusted to be the same.

On the other hand, the refractive index of the liquid crystal layer 525 is the refractive index of the first substrate 523 and the refractive index of the second substrate 527 in a state where a voltage is applied to the liquid crystal layer 525 (also referred to as a second state of the liquid crystal layer 525). Adjusted to be different from.

The liquid crystal layer 525 contains a liquid crystal material. The orientation state of the liquid crystal molecules in the liquid crystal material when the voltage is applied and the orientation state of the liquid crystal molecules when the voltage is not applied are different from each other. The liquid crystal molecule can be appropriately selected depending on the refractive index of the first substrate 523 and the refractive index of the second substrate 527. For example, the liquid crystal material may be composed of a cholesteric liquid crystal, a nematic liquid crystal, or the like.

(Second board)
The second substrate 527 is arranged behind the first substrate 523 and facing the back surface of the first substrate 523. The second substrate 527 has a plate shape that curves convexly toward the front side. The surface of the second substrate 527 is a convex curved surface that curves convexly toward the + side in the Z direction. The back surface of the second substrate 527 is a concave curved surface that curves concavely toward the + side in the Z direction.

(Adhesive layer)
The adhesive layer 528 is usually arranged between the first substrate 523 and the second substrate 527 in the lens portion 522, and adheres the first substrate 523 and the second substrate 527. When the first electrode 524 and the second electrode 526 are also arranged in the normal lens portion 522, the adhesive layer 528 is arranged between the first electrode 524 and the second electrode 526. The adhesive layer 528 also has a function of sealing the liquid crystal material constituting the liquid crystal layer 525.

The first optical element 52 may further have other components having translucency, if necessary. Examples of such other components include insulating layers and alignment films.

The insulating layer prevents conduction between the first electrode 524 and the second electrode 526. For example, the insulating layer is arranged between the first electrode 524 and the liquid crystal layer 525, and between the liquid crystal layer 525 and the second electrode 526, respectively.

The alignment film controls the alignment state of the liquid crystal material in the liquid crystal layer 525. For example, the alignment film is arranged between the first electrode 524 and the liquid crystal layer 525, and between the liquid crystal layer 525 and the second electrode 526, respectively.

(Second optical element)
The second optical element 53 is the optical element 1B according to the second embodiment described above. The second optical element 53 is fixed to the first surface (the surface on the + side in the Z direction) of the first optical element 52 by a fixing means such as adhesion.

In the case of the present embodiment, the second optical element 53 is provided so that the right side (X direction + side) in FIG. 5 coincides with the upper side in FIG. 25. In other words, the second optical element 53 is provided so that the right side (X direction + side) in FIG. 5 coincides with the upper side of the lens 51 in the state of using the spectacles.

Therefore, in FIG. 1, the + side (+ θ side) with respect to the incident angle θ is the upper side of the lens 51 in the state of using the spectacles. On the other hand, in FIG. 1, the − side (−θ side) with respect to the incident angle θ is the lower side of the lens 51 in the state of using the spectacles.

As described above, in the optical element 1B according to the second embodiment, in the first state, the maximum absorption direction of each of the dichroic dyes 142 is on the + side with respect to the incident angle θ (specifically, the incident angle θ = +60). °) is included.

In such an optical element 1B, among the incident light L incident on the optical element 1B from the + side with respect to the incident angle, the amount of light emitted from the optical element 1B is incident on the optical element 1B from the-side with respect to the incident angle. Among the incident light L, the incident light L has a property (anisity regarding the absorption rate) that is smaller than the amount of the emitted light emitted from the optical element 1B.

Therefore, the second optical element 53 (optical element 1B) has an absorption rate with respect to the incident light L incident on the second optical element 53 (optical element 1B) from above in the state of using the glasses, and the second optical element 53 from below. It has a property (anisity regarding the absorption rate) that is larger than the absorption rate for the incident light L incident on the (optical element 1B).

(Detection unit)
Each of the

detection units

54a and 54b has, for example, a capacitance type detection pad. The detection pad may be a known detection pad that can be used as a touch sensor. When the user's finger touches the

detection units

54a and 54b, the

detection units

54a and 54b detect the change in capacitance caused by the contact, respectively.

The detection unit 54a is provided on one of the temples 502a. A part of the detection unit 54a is exposed to the outside from one of the temples 502a. The user touch-operates the portion exposed to the outside in the detection unit 54a.

The detection unit 54b is provided on the other temple 502b. A part of the detection unit 54b is exposed to the outside from the other temple 502b. The user touch-operates the portion exposed to the outside in the detection unit 54b.

(Control unit)
On the other hand, the control unit 55a switches between a state in which a voltage is applied to the first optical element 52 and a state in which the voltage is not applied, based on the operation of the user.

The control unit 55a is electrically connected to the detection pad of the detection unit 54a via the wiring 57a. Further, the control unit 55a is electrically connected to the first electrode 524 and the second electrode 526 of the first optical element 52 via the wiring 57a.

When the detection unit 54a detects the contact of the object, the control unit 55a applies a voltage to the first optical element 52 or stops applying the voltage to the first optical element 52 to obtain the first optical. The focal length (power) of the liquid crystal lens unit 521 in the element 52 is switched.

The other control unit 55b switches between a state in which a voltage is applied to the second optical element 53 (optical element 1B) and a state in which a voltage is not applied, based on the user's operation.

The control unit 55b is electrically connected to the detection pad of the detection unit 54b via the wiring 57b. Further, the control unit 55b is electrically connected to the first electrode 12 and the second electrode 16 (see FIG. 1) of the second optical element 53 (optical element 1B) via the wiring 57b.

The control unit 55b applies a voltage to the second optical element 53 (optical element 1B) or a voltage to the second optical element 53 (optical element 1B) when the detection unit 54b detects contact with the object. Is stopped, and the orientation state of the liquid crystal layer 14 in the second optical element 53 (optical element 1B) is switched.

Under the control of the control unit 55b, the second optical element 53 (optical element 1B) switches between the first state and the second state. The first state and the second state of the second optical element 53 (optical element 1B) are as described above.

(Power supply)
One power source 56a supplies electric power to the control unit 55a and the detection unit 54a. In the present embodiment, the power supply 56a is a rechargeable battery pack that is detachably held at the rear end portion (second end portion) of one temple 502a. The power source 56a may be, for example, a nickel-metal hydride rechargeable battery.

The other power source 56b supplies power to the control unit 55b and the detection unit 54b. In the present embodiment, the power supply 56b is a rechargeable battery pack that is detachably held at the rear end portion (second end portion) of the other temple 502b. The power source 56b may be, for example, a nickel-metal hydride rechargeable battery.

(Operation of electronic glasses)
An example of the operation of the electronic glasses 5 will be described. First, a state in which a voltage is not applied to the first optical element 52 of the electronic eyeglasses 5 (first off state) will be described.

In the first off state, in the first optical element 52, the refractive index of the liquid crystal layer 525 and the refractive index of the first substrate 523 and the second substrate 527 are almost the same. Therefore, in the first optical element 52, the lens effect caused by the liquid crystal layer 525 does not occur.

When one of the detection units 54a detects contact with an object (for example, a user's finger) which is a conductor in the first off state, the detection unit 54a sends detection information based on this contact to the control unit 55a. .. The control unit 55a applies a voltage to the first optical element 52 based on the acquired detection information of the detection unit 54a in the first off state.

As a result, the orientation state of the liquid crystal material in the liquid crystal layer 525 of the first optical element 52 changes, and the power (refractive index) of this liquid crystal layer changes. The state in which the voltage is applied to the first optical element 52 is referred to as the first on state of the electronic eyeglasses 5.

In the first on state, the refractive index of the liquid crystal layer 525 in the first optical element 52 and the refractive index of the first substrate 523 and the second substrate 527 are different from each other. Therefore, the lens effect caused by the liquid crystal layer 525 occurs in the first optical element 52. As a result, the power of the region corresponding to the liquid crystal layer 525 in the first optical element 52 changes.

Further, when one of the detection units 54a detects the contact of an object (for example, a user's finger) which is a conductor in the first ON state, the detection unit 54a outputs the detection information based on this contact to the control unit 55a. Send to. The control unit 55a stops applying the voltage to the first optical element 52 based on the acquired detection information of the detection unit 54a in the first on state. As a result, the state of the first optical element 52 becomes the first off state.

Further, the state in which the voltage is not applied to the second optical element 53 of the electronic eyeglasses 5 (second off state) corresponds to the first state of the optical element 1B described above.

As described above, in the second off state, the second optical element 53 (optical element 1B) has anisotropy regarding the absorptivity. Therefore, in the second off state, in the second optical element 53 (optical element 1B), the absorption rate of the incident light L incident on the second optical element 53 (optical element 1B) from above is incident on the optical element 1B from below. It is larger than the absorption rate for the incident light L.

When the other detection unit 54b detects contact with an object (for example, a user's finger) which is a conductor in the second off state, the detection unit 54b sends detection information based on this contact to the control unit 55b. .. The control unit 55b applies a voltage to the second optical element 53 (optical element 1B) based on the acquired detection information of the detection unit 54b in the second off state.

As a result, the orientation state of the liquid crystal molecules 141 and the dichroic dye 142 in the liquid crystal layer 14 (see FIG. 1) of the second optical element 53 (optical element 1B) changes. The state in which the voltage is applied to the second optical element 53 (optical element 1B) is referred to as the second on state of the electronic eyeglasses 5. The second on state corresponds to the second state of the optical element 1B.

As described above, the second optical element 53 (optical element 1B) does not have anisotropy regarding the absorptivity in the second on state. Therefore, in the second ON state, the second optical element 53 (optical element 1B) has the absorption rate for the incident light L incident on the second optical element 53 (optical element 1B) from above and the second optical element 53 from below. The absorption rate for the incident light L incident on (optical element 1B) is equal to or substantially equal to.

Further, when the detection unit 54b detects contact with an object (for example, a user's finger) which is a conductor in the second ON state, the detection unit 54b sends detection information based on this contact to the control unit 55b. .. The control unit 55b stops applying a voltage to the second optical element 53 (optical element 1B) based on the acquired detection information of the detection unit 54b in the second ON state. As a result, the state of the first optical element 52 becomes the first off state.

The state of the first optical element 52 (first off state and first on state) and the state of the second optical element 53 (optical element 1B) (second off state and second on state) are defined by the user. It may be realized by an appropriate combination based on the operation.

(About the forward tilt angle of the lens)
Here, the forward tilt angle of the lens 51 will be described. The lens 51 shown in FIG. 27 is provided so that the thickness direction of the lens 51 is parallel to the front-back direction (left-right direction in FIG. 27) of the user. _{The forward tilt angle δ 51} (see FIG. 28) of the lens 51 shown in FIG. 27 is 0 °.

Light incident on the lens 51 in a direction parallel (Z-direction) in the longitudinal direction of the user is the incident light L _1. Moreover, light incident obliquely from above of the user to the lens 51 is incident light L ₂ to be incident on the lens 51 from about the incident angle + side (+ theta side) in FIG. 27. Light incident obliquely from below of the user to the lens 51 is directed to the incident angle of 27 - an incident light L ₃ incident from the side (- [theta] side) lens 51.

FIG. 28 shows the lens 51 when the thickness direction of the lens 51 is tilted by 30 ° with respect to the user's front-back direction (left-right direction in FIG. 27). _{The forward tilt angle δ 51} of the lens 51 shown in FIG. 28 is 30 °. _{By changing the forward tilt angle δ 51} of the lens 51 in this way, it is possible to adjust the relationship between the incident angle of the lens 51 and the transmittance _{according to the forward tilt angle δ 51.} That is, by adjusting the forward tilt angle of the lens 51, the direction of the incident light L for which the absorption rate is desired to be increased (in other words, the transmittance is desired to be increased) can be adjusted.

According to the electronic glasses 5 as described above, the state having anisotropy regarding the absorption rate (first state) and the difference regarding the absorption rate depending on the application of the voltage to the second optical element 53 (optical element 1B). It is possible to switch between a state without anisotropy (second state) and a state without anisotropy.

In particular, in the second off state of the second optical element 53 (optical element 1B), the absorption rate for the incident light L incident on the lens 51 from above is larger than the absorption rate for the incident light L incident on the lens 51 from below. .. If the second off state is realized in the daytime when the position of the sun is high, the absorption rate for sunlight incident on the lens 51 from above can be increased. As a result, the visibility of the user can be improved.

(Supplementary note regarding this embodiment)
In the present embodiment, the case where the optical element 1B of the second embodiment is applied as the second optical element 53 has been described. However, the second optical element 53 is not limited to the optical element 1B of the second embodiment. The second optical element 53 may be any of the optical elements according to the first to twelfth embodiments.

Further, in the present embodiment, the second optical element 53 (optical element 1B) includes a direction including the maximum absorption direction of each of the dichroic dyes 142 of the second optical element 53 (optical element 1B) (in the case of the present embodiment). , The + side with respect to the incident angle θ) is arranged so as to coincide with the upper side of the lens 51 in the state of use of the spectacles.

However, the arrangement of the second optical element 53 (optical element 1B) is not limited to this. For example, when it is desired to increase the absorption rate of the incident light incident on the lens 51 from the right direction of the lens 51 in the use state of the spectacles, the maximum absorption direction of each of the dichroic dyes 142 of the second optical element 53 is included. The second optical element 53 may be arranged so that the direction (in the case of the present embodiment, the + side with respect to the incident angle θ) coincides with the right side of the lens 51 in the state of using the spectacles. The arrangement mode of the second optical element 53 may be different between the left and right lenses 51.

[Embodiment 14]
The electronic eyeglasses 5B according to the fourteenth embodiment of the present invention will be described with reference to FIG. 29. FIG. 29 is a schematic diagram of the electronic eyeglasses 5B.

The electronic eyeglasses 5B of the present embodiment are different from the electronic eyeglasses 5 of the thirteenth embodiment in that the first optical element 52 and the second optical element 53 are independently provided. The other configurations of the first optical element 52 and the configuration of the second optical element 53 are the same as those of the thirteenth embodiment.

Further, the electronic eyeglasses 5B of the present embodiment has a forward tilt angle adjusting mechanism 7 for adjusting the forward tilt angle of the second optical element 53. The forward tilt angle adjusting mechanism 7 is provided on the frame 50, and has a first support portion 71, a second support portion 72, and a connection portion 73 connecting the first support portion 71 and the second support portion 72. Have.

The first support portion 71 supports the first optical element 52 in a non-swingable state. Further, the second support portion 72 supports the second optical element 53 in a swingable state. The user can adjust the forward tilt angle of the second optical element 53 by swinging the second optical element 53.

The chain double-dashed line in FIG. 29 shows the second optical element 53 in the reference state where the forward tilt angle is 0 °. The user, for example, when to the second rotating optical element 53 30 ° in the direction indicated by the arrow A ₁ in FIG. 29, the forward inclination of the second optical element 53 becomes the 30 ° as shown in Figure 28.

The user can adjust the direction of the incident light L for which the absorption rate is desired to be increased (in other words, the transmittance is desired to be increased) by adjusting the forward tilt angle of the second optical element 53.

(Additional note)
As described above, in the 13th and 14th embodiments, the case where the application target of the optical element according to the present invention is electronic eyeglasses has been described. However, the application target of the optical element according to the present invention is not limited to electronic eyeglasses. The optical element according to the present invention can be applied to various eyewear.

For example, the optical element according to the present invention can also be applied to smart glasses having a lens having an information display function. By applying the optical element according to the present invention to such smart glasses, it is possible to increase the absorption rate for incident light incident on the lens from a specific direction. As a result, it is possible to improve the visibility of the information displayed on the portion of the lens corresponding to the specific direction. In addition, the optical element according to the present invention can also be applied to VR (Virtual Reality) glass and the like.

The disclosures of the specification, drawings and abstract contained in the Japanese application of Japanese Patent Application No. 2020-104044 filed on June 16, 2020 are all incorporated herein by reference.

The optical element according to the present invention can be applied to various eyewear.

1,1B, 1C, 1D, 1E, 1Eb,

1F Optical element

1G, 1H, 1J, 1Jb, 1K, 1Kb, 1L,

1M Optical element

101e, 101f, 101j,

101k First element

102e, 102f, 102j, 102k Two elements 11 First substrate 12

First electrode

13, 13B, 13L, 13M

First alignment film

14, 14B Liquid crystal layer 14L1, 14M1 First liquid crystal layer 14L2, 14M2 Second liquid crystal layer 141 Liquid crystal molecule 142 Bicolor dye R ₁ 1st region R ₂ 2nd region R ₃ Intermediate region 15, 15B, 15L 2nd alignment film 16 2nd electrode 17 2nd substrate 18 Polarizing plate 19 Half wave plate 20 1st adhesive layer 21 2nd adhesive layer 5 Electronic optics 50 Frame 501 Front 502a, 502b Temple 51 Lens 52 First optical element 521 Liquid crystal lens part 522 Normal lens part 523 First substrate 523a Diffraction area 523b Convex part 523c First convex strip 524 First electrode 525 Liquid crystal layer 526 Second electrode 527 Two boards 528 Adhesive layer 53 Second

optical element

54a,

54b Detection part

55a,

55b Control part

56a,

56b Power supply

57a, 57b Wiring 7 Forward tilt angle adjustment mechanism 71 First support part 72 Second support part 73 Connection part

Claims

A liquid crystal cell containing a liquid crystal molecule and a dichroic dye and having a facing first surface and a second surface is provided.
The pretilt angle, which is the inclination angle of the dichroic dye in contact with at least one of the first surface and the second surface, with respect to the one surface is 5 ° or more.
Optical element.
The optical element according to claim 1, further comprising a polarizing plate fixed to the first surface or the second surface.
A pair of transparent electrodes that sandwich the liquid crystal cell are further provided.
The optical element according to claim 1 or 2, wherein the liquid crystal molecule changes its orientation state based on the application of a voltage to the pair of transparent electrodes.
The optical element according to claim 1, wherein the pretilt angle is 10 ° or more.
The first liquid crystal cell and the second liquid crystal cell, which are the liquid crystal cells, respectively,
The optical element according to claim 1, further comprising a half-wave plate provided between the first liquid crystal cell and the second liquid crystal cell.
Each of the first liquid crystal cell and the second liquid crystal cell is an intermediate provided between a first region containing the liquid crystal molecules in contact with the first surface and a second region containing the liquid crystal molecules in contact with the second surface. The optical element according to claim 5, wherein the region includes the liquid crystal molecule having a tilt angle of 40 ° or more and 70 ° or less, which is an inclination angle with respect to the first surface.
A pair of first transparent electrodes that sandwich the first liquid crystal cell and a pair of second transparent electrodes that sandwich the second liquid crystal cell are further provided.
In the first liquid crystal cell, the orientation of the liquid crystal molecules is changed by applying a voltage to the pair of first transparent electrodes, and the orientation of the liquid crystal molecules is changed.
The optical element according to claim 5 or 6, wherein the second liquid crystal cell changes the orientation of liquid crystal molecules by applying a voltage to the pair of second transparent electrodes.
The optical element according to any one of claims 5 to 7, wherein the orientation of the liquid crystal molecules in the first liquid crystal cell and the second liquid crystal cell is a hybrid orientation, respectively.
In the first liquid crystal cell, the alignment state of the liquid crystal molecules is controlled by a pair of first diagonal alignment films sandwiching the first liquid crystal cell.
The optical element according to any one of claims 5 to 7, wherein the second liquid crystal cell is controlled by a pair of second diagonally aligned films sandwiching the second liquid crystal cell in an orientation state of liquid crystal molecules.
Eyewear provided with an electrically active lens having the optical element according to any one of claims 1 to 9.