JP7358840B2 - optical components - Google Patents

Description

Embodiments of the present disclosure relate to optical members.

2. Description of the Related Art Techniques for optical members that limit transmission of light incident from the outside have been known (for example, Patent Document 1).
The optical member of Patent Document 1 has a plurality of light transmitting portions and light absorbing portions arranged alternately, and among the light incident on the optical member, in the arrangement direction of the light transmitting portions, the light incident from the front direction is not transmitted. However, the obliquely incident light is absorbed by the light absorption part and blocked.

Japanese Patent Application Publication No. 2018-87899

However, conventional optical members may absorb too much incident light, resulting in an insufficient amount of transmitted light, depending on the intended use.
Furthermore, there has been a desire to restrict the incidence of light from a specific oblique direction (angular range) to an optical member, and to allow light to be transmitted from other directions. However, for example, in the louver film described in Patent Document 1, in the arrangement direction of the light shielding parts, light from the front direction is transmitted, but light from an oblique direction is blocked, and light from one side of the light from the oblique direction is transmitted. It is not possible to transmit the incident light and block the incident light from the other side.

Therefore, the inventors of the present application disclosed in Japanese Patent Application No. 2019-044799 an optical member in which the cross-sectional shape of the light shielding portion is a wedge-shaped asymmetrical in the arrangement direction.
In optical components having such light-shielding parts, the thickness of the light-shielding parts (dimensions in the arrangement direction) differs in the depth direction (thickness direction of the optical member). When used as a part-forming material, the light absorption rate of the light-shielding part-forming material cannot be increased because even thick parts are sufficiently cured by light. Therefore, in the thin part of the light shielding part, the light absorption rate decreases and light cannot be absorbed sufficiently, causing light to pass through the light absorbing part, resulting in a problem that the light control function of the optical member is reduced. Ta.

An object of the embodiments of the present disclosure is to provide an optical member that can block light incident from a specific direction, transmit much of the light incident from other directions, and has a high light control function. It is.

The present invention solves the above problems by the following solving means. Note that, in order to facilitate understanding, the description will be given with reference numerals corresponding to the embodiments of the present invention, but the present invention is not limited thereto.
The first disclosed embodiment is an optical member that blocks incident light from a specific angular range, has light transparency, and has a unit optical shape (21, 221) on one surface. A plurality of optical shape layers (20, 220) arranged in (20a, 220a), and a light shielding part (30, 230) provided between the adjacent unit optical shapes to shield incident light, In a cross section parallel to the arrangement direction of the unit optical shapes and parallel to the thickness direction of the optical member, the light shielding portion includes a first portion (33) extending along the thickness direction, and one of the first portions. a second portion (34) extending from the surface side end portion to one side in the arrangement direction, and a point on the one side of the tip portion of the first portion and the one side of the tip portion of the second portion. These are optical members (1, 2) in which the unit optical shape protrudes toward the light shielding part from a virtual straight line (S2) passing through a point on the opposite side to the surface side.
In a second disclosed embodiment, in the optical member according to the first disclosed embodiment, a dimension at a portion where the dimension in the arrangement direction of the unit optical shapes (21, 221) is the smallest in the first portion (33) is provided. is d1 [μm], and the dimension of the optical member in the second portion (34) where the dimension in the thickness direction is the smallest is d2 [μm], then d1≦d2, and the OD value at the dimension d1 is 0.5 or more and 2 or less, and the OD value in dimension d2 is 1 or more and 3 or less.
A third disclosed embodiment is the optical member according to the first disclosed embodiment or the second disclosed embodiment, in which the base layer (10) has a light transmittance of 20% or more and 80% in the thickness direction. The optical members (1, 2) are as follows.
In a fourth disclosed embodiment, in any of the optical members from the first disclosed embodiment to the third disclosed embodiment, the unit optical shape (21, 221) is an array of the unit optical shapes. The cross-sectional shape in a cross section parallel to the direction and parallel to the thickness direction of the optical member is a polygonal shape, and the light passing through the optical member is located on the one surface (20a, 220a) and enters or exits. a first surface (22) that forms an angle that is parallel or can be considered parallel to the thickness direction of the optical member, and whose edge on the one surface side coincides with one end of the first surface. a surface (23), and three surfaces located on the other side of the first surface and forming a folded surface facing the second surface, which are located on the rearmost side and are inclined with respect to the thickness direction. a third surface (24) that is located on the one side of the third surface and that forms an angle that is parallel or can be considered parallel to the sheet surface; a fifth surface (26) located on the one surface side of the optical member and inclined with respect to the thickness direction of the optical member, the other end (22a) of the first surface of the unit optical shape and the The first angle (θ4) formed by the straight line (S) passing through the edge (23a) of the second surface on the opposite side to the one surface side with the thickness direction of the optical member is the first angle (θ4) in the unit optical shape. an edge (24a) of the third surface on the opposite side to the one surface in the thickness direction of the optical member, and an end of the fourth surface on the fifth surface side, which is smaller than the critical angle. The optical members (1, 2) are such that the straight line (S2) passing through the edge (25a) is smaller than the second angle (θ3) made with the thickness direction of the optical member.
In a fifth disclosed embodiment, in the optical member according to the fourth disclosed embodiment, the first angle (θ4) is constant in the arrangement direction of the unit optical shapes, and the unit optical shapes ( The arrangement pitch (P) of the light shielding parts (230) in the arrangement direction of the optical member (221) is not constant.
In a sixth disclosed embodiment, in any of the optical members from the first disclosed embodiment to the fifth disclosed embodiment, the light shielding portion (30, 230) is configured such that the unit optical shape (21, The optical members (1, 2) have a larger refractive index than the optical members (221).
The seventh disclosed embodiment is a window (120) comprising any of the optical members (1, 2) from the first disclosed embodiment to the sixth disclosed embodiment.

According to embodiments of the present disclosure, it is possible to provide an optical member that can block light incident from a specific direction, transmit much of the light incident from other directions, and has a high light control function. I can do it.

It is a figure showing an example of the use state of optical member 1 of a 1st embodiment. It is a figure explaining optical member 1 of a 1st embodiment. FIG. 3 is a diagram showing the state of light incident on the optical member 1 of the first embodiment. It is a figure explaining the optical member 2 of 2nd Embodiment. It is a figure which shows the deformation form of an optical member. It is a figure which shows the deformation form of an optical member. It is a figure which shows the deformation form of an optical member. It is a figure explaining the optical member 9 of a comparative example.

Embodiments of the present disclosure will be described below with reference to the drawings and the like. Note that each figure shown below, including FIG. 1, is a schematic diagram, and the size and shape of each part are appropriately exaggerated for easy understanding.
In this specification, terms that specify shapes or geometrical conditions, such as terms such as parallel and orthogonal, do not have a strict meaning, but also have a similar optical function and are used to the extent that they can be considered parallel or orthogonal. This also includes states with errors.
In addition, in this specification, numerical values such as dimensions and material names of each member described are an example of an embodiment, and are not limited to these, and may be appropriately selected and used.

In this specification, words such as plate and sheet are used. Generally, these are used in the order of thickness: plate, sheet, and film, and this specification is also used accordingly. However, since there is no technical meaning in these different uses, these words can be replaced as appropriate.
In addition, in this specification, the sheet surface refers to the surface that is the plane direction of the sheet when the sheet is viewed as a whole, and the same term is used in this specification and in the claims. It is used as a definition.

(First embodiment)
FIG. 1 is a diagram showing an example of a usage state of the optical member 1 of the first embodiment.
FIG. 2 is a diagram illustrating the optical member 1 of the first embodiment. In FIG. 2, a part of a cross section parallel to the thickness direction (Z direction) of the optical member 1 and parallel to the arrangement direction (X direction) of the unit optical shapes 21 is shown in an enlarged manner.
Here, in order to facilitate understanding, an XYZ orthogonal coordinate system is appropriately provided in each of the figures shown below, including FIGS. 1 and 2. In this coordinate system, the thickness direction of the optical member 1 is defined as the Z direction, and among the directions perpendicular to the Z direction, the arrangement direction of the unit optical shapes 21 to be described later is defined as the X direction, and the thickness direction of the optical member 1 is defined as the direction perpendicular to the X direction and the Z direction. The width direction of is the Y direction. Further, in the thickness direction (Z direction), the +Z side is the front side of the optical member 1, and the -Z side is the back side of the optical member 1.

The optical member 1 is a sheet-like member that has a function of blocking light incident from a predetermined direction (angular range). The sheet surface of the optical member 1 is parallel to the XY plane.
As shown in FIG. 2, the optical member 1 includes a base material layer 10, an optical shape layer 20, a light shielding part 30, a bonding layer 40, and a second base material layer 50, which are laminated in order from the back side (-Z side). There is.

In this embodiment, the optical member 1 is formed in a rectangular shape when viewed from a direction parallel to its thickness direction, and is provided in a skylight 120 of a roof 110 of a building 100, as shown in FIG. Among outside light such as sunlight, light that enters from a specific angle range is blocked to prevent it from entering the room as much as possible. For example, by manufacturing the optical member 1 so that it can block only the western sunlight (light entering from the west side) and placing it in the skylight 120, the incidence of western sunlight into the room can be restricted and the indoor environment can be improved. Can be maintained comfortably.
In this embodiment, an example will be described in which the optical member 1 is a member that blocks light that obliquely enters from the +X side to the -X side in the cross section shown in FIG.

In this embodiment, the optical member 1 is used by being attached to the inside (indoor side) of the skylight 120 with a transparent adhesive (not shown), with the surface (+Z side surface) facing the skylight 120. Although the description will be given by way of example, the present invention is not limited to this, and may be used by being attached to the outdoor side of the skylight 120 with the back surface (-Z side surface) facing the skylight 120 side.
Furthermore, the optical member 1 is not limited to being placed in the building 100, but may also be used in a window of a vehicle, a partition, or the like.

The base layer 10 is a sheet-like member having optical transparency, and an optically shaped layer 20 is integrally formed on its surface (+Z side surface). The base material layer 10 is a layer that serves as a base material for forming the optically shaped layer 20.
The base material layer 10 is made of, for example, polyester resin such as PET (polyethylene terephthalate) having high light transmittance, acrylic resin, styrene resin, acrylic styrene resin, PC (polycarbonate) resin, alicyclic polyolefin resin, TAC (triacetyl resin), etc. Cellulose) resin, etc.
Further, the thickness of the base layer 10 can be changed depending on the intended use of the optical member 1, and the thickness in this embodiment is approximately 250 μm.

The base material layer 10 of this embodiment has a light attenuation effect, and has a light transmittance of 50% in the thickness direction (Z direction). When the base layer 10 has a light attenuation effect, the transmittance of the base layer 10 in the thickness direction (Z direction) is preferably 20 to 80%.
In addition, the base layer 10 that exhibits such a light attenuation effect has the resin material forming the aforementioned base layer 10 containing dark-colored particles such as gray or black, dark-colored dyes, pigments, etc. , carbon black, graphite, a metal salt such as black iron oxide, etc., as a coloring agent.
By using such a base material layer 10, the intensity of transmitted light can be adjusted by appropriately weakening the intensity of light transmitted through the optical member 1, and the light that should be blocked can be made to pass through the light shielding part 30. If a small amount of light leaks out, the light can be weakened and the light blocking performance can be improved.
In addition, in this embodiment, although the base material layer 10 showed the example which has a light attenuation effect, the base material layer 10 may not have a light attenuation effect not only this but.

The optical shape layer 20 is a layer having optical transparency formed on the surface (+Z side surface) of the base material layer 10, and has a plurality of unit optical shapes 21 arranged in the X direction.
The optically shaped layer 20 is made of ultraviolet curable resin such as urethane acrylate, polyester acrylate, epoxy acrylate, polyether acrylate, polythiol, butadiene acrylate, etc., which has high light transmittance. The optical shape layer 20 of this embodiment is formed of urethane acrylate resin (refractive index n1=1.52) that is cured by ultraviolet rays.
Note that the resin constituting the optically shaped layer 20 is not limited to the above-mentioned ultraviolet curable resin, but may be formed from other ionizing radiation curable resins such as electron beam curable resins, or thermoplastic resins. It's okay.

The unit optical shape 21 has a polygonal cross-sectional shape, and as shown in FIG. a third surface 24, a fourth surface 25, and a fifth surface 26 provided on the +X side of the first surface 22 and facing the second surface 23; have.

The first surface 22 is located on one surface 20a of the optically shaped layer 20 in the cross section of the optical member 1 shown in FIG. is provided between the surface 23 and the fifth surface 26.
The first surface 22 is a surface on which light passing through the optical member 1 enters or exits, and in this embodiment, the light entering from the front surface side (+Z side) of the optical member 1 is directed into the unit optical shape 21. It is a transparent surface. The first surfaces 22 of the plurality of unit optical shapes 21 arranged are all located on one surface 20a of the optical shape layer 20, and the position in the thickness direction (Z direction) is constant.
Since the first surface 22 is parallel to the sheet surface of the optical member 1, the inclination angle θ1 [°] of the first surface 22 with respect to the sheet surface is θ1=0°. In FIG. 2, since θ1=0°, the angle θ1 is not shown.
The dimension of the first surface 22 in the arrangement direction (X direction) of the unit optical shapes 21 is a.

The second surface 23 is a surface provided on the -X side of the unit optical shape 21 in the arrangement direction (X direction) of the unit optical shape 21, and the edge on the surface side (+Z side) is the first surface. It coincides with the edge of surface 22 on the -X side. The second surface 23 is in contact with the light shielding portion 30 adjacent to the unit optical shape 21 on the -X side.

The second surface 23 is a surface parallel or substantially parallel to the thickness direction (Z direction). Substantially parallel to the thickness direction means a state in which the second surface 23 forms an angle that can be considered parallel to the thickness direction (Z direction). Parallel or substantially parallel to the thickness direction means that the angle θ2 [°] that the second surface 23 makes with the thickness direction satisfies 0°≦θ2≦5°. If the angle θ2 satisfies this angle range, the second surface 23 is inclined so that the edge on the front side (+Z side) is located on the +X side rather than the edge on the back side (-Z side). (that is, inclined toward the +X side) or may be inclined so as to be located on the −X side (that is, inclined toward the −X side). Here, tilting to the -X side refers to a state in which the tilt is negative in the XZ coordinate system shown in Figure 2, etc., and tilting to the +X side refers to a state in which the tilt is negative (negative) in the XZ coordinate system shown in Figure 2, etc. This refers to a state where the slope is plus (positive) in the XZ coordinate system shown.
The second surface 23 of this embodiment is formed parallel to the thickness direction (Z direction), that is, θ2=0°. In FIG. 2, since θ2=0°, the angle θ2 is not shown.

The third surface 24, the fourth surface 25, and the fifth surface 26 are surfaces forming a folded surface provided on the +X side of the unit optical shape 21 in the arrangement direction (X direction) of the unit optical shape 21. and faces the second surface 23 described above. The third surface 24 , fourth surface 25 , and fifth surface 26 are in contact with the light shielding section 30 adjacent to the +X side of the unit optical shape 21 .

The third surface 24 is a surface that contacts a first portion 33 of the light shielding part 30 (described later) from the -X side, and is located on the back side (-Z side) of the fourth surface 25 and the fifth surface 26. ing.
The fourth surface 25 is a surface that contacts a second portion 34 (described later) of the light shielding section 30 from the back surface side (-Z side), and is parallel or substantially parallel to the sheet surface (XY plane). "Substantially parallel to the sheet surface" refers to a state in which the fourth surface 25 is inclined at an angle small enough to be considered parallel to the sheet surface (XY plane). Note that when the fourth surface 25 is inclined with respect to the seat surface, the edge on the third surface 24 side (+X side) is closer to the back surface than the edge on the fifth surface 26 side (-X side). It is preferable to be inclined so as to be located on the -Z side. In this embodiment, the fourth surface 25 is parallel to the sheet surface.
The fifth surface 26 is a surface that contacts a second portion 34, which will be described later, from the −X side. The edge of the fifth surface 26 on the front side (+Z side) coincides with the edge of the first surface 22 on the −X side.

The third surface 24 and the fifth surface 26 are inclined toward the −X side in the cross section of the optical member 1 shown in FIG. The third surface 24 and the fifth surface 26 may or may not be parallel.
The unit optical shape 21 has a cross-sectional shape shown in FIG. 2 extending in the width direction (Y direction).

The light shielding portion 30 is a portion that shields incident light, and is provided in a valley between adjacent unit optical shapes 21 . The light shielding part 30 of this embodiment is provided so as to fill the valley between the unit optical shapes 21, and includes a first part 33 extending toward the back surface side (-Z side) along the thickness direction (Z direction), It has a second portion 34 extending from the surface side (+Z side) of the portion 33 toward the −X side, and has a so-called L-shape in the cross section of the optical member 1 shown in FIG.

The surface 31 of the light shielding portion 30 closest to the surface (+Z side) forms the same plane as the first surface 22 of the unit optical shape 21 . In the arrangement direction of the unit optical shape 21 and the light shielding part 30, the dimension of the surface 31 of the light shielding part 30 is defined as b.
Further, the light shielding portion 30 has a flat portion 32 at the tip portion on the back surface side (-Z side) of the first portion 33. This flat portion 32 is parallel to the sheet surface in the cross section shown in FIG. 2, and the angle θ5 [°] that the flat portion 32 makes with respect to the sheet surface is θ5=0°. In FIG. 2, since θ5=0°, the angle θ5 is not shown.

Next, the width (dimension in the X direction) of the first portion 33 of the light shielding portion 30 will be explained. In this embodiment, the first portion 33 has a so-called wedge-shaped cross-sectional shape as shown in FIG. The wedge-shaped shape means a shape that is wide at one end and gradually narrows toward the other end, and includes shapes such as a triangular shape and a trapezoidal shape. The dimension of the first portion 33 in the arrangement direction (X direction) of the light shielding portions 30 is large on the front side (+Z side) and becomes smaller toward the back side (−Z side). In the first portion 33, the width of the flat portion 32 having the smallest width (dimension in the X direction) is defined as a dimension d1. Note that the first portion 33 may have a rectangular cross-sectional shape as shown in FIG. 2 .
Further, the thickness (dimension in the Z direction) of the second portion 34 of the light shielding portion 30 is defined as a dimension d2.

In the cross section shown in FIG. 2, the unit optical shape 21 is located at the tip of the back surface side (-Z side) of the first portion 33 of the light shielding part 30 and at the -X side (the most back surface side of the third surface 24). -Z side)) and a point 25a that is the tip of the -X side of the second portion 34 and the back side (coinciding with point 25a that is the -X side edge of the fourth surface 25). It has a shape that protrudes toward the light shielding part 30 side adjacent to the +X side, rather than a straight line passing through (that is, a straight line S2 shown by a dashed line in FIG. 2). That is, the light shielding part 30 has a concave shape on the -X side.
The light shielding part 30 has a cross-sectional shape shown in FIG. 2 extending in the width direction (Y direction).

Moreover, the light shielding part 30 of this embodiment is colored with particles such as gray or black, or coloring materials such as dyes and pigments, and has light absorbing properties. Thereby, the light shielding part 30 absorbs the light that is incident on the light shielding part 30 out of the light that is incident on the optical member 1, and blocks the light.
The base material of the light shielding part 30 may be the same material as the optically shaped layer 20 described above, for example, an ultraviolet curing type such as urethane acrylate, polyester acrylate, epoxy acrylate, polyether acrylate, polythiol, or butadiene acrylate. Resin etc. are suitable. Further, as the base material of the light shielding part 30, a photoreactive resin that hardens in response to other light may be used.
In addition, examples of the coloring material used in the light shielding part 30 include dark-colored particles such as gray and black, dark-colored dyes and pigments, and metal salts such as carbon black, graphite, and black iron oxide. .

In the light shielding part 30, both the first part 33 and the second part 34 are formed of the same resin, and the OD (Optical Density) value changes depending on the thickness (width) of each part. The light shielding portion 30 has an OD value of 0.5 or more and 2 or less at a portion having a thickness of dimension d1 (near the flat portion 32), and an OD value of 0.5 or more and 2 or less at a portion having a thickness of dimension d2 (second portion 34). It is preferable that the value is 1 or more and 3 or less from the viewpoint of sufficiently absorbing light.
If the OD value is smaller than the above range, when light enters the light shielding part 30, the light will not be absorbed sufficiently by the light shielding part 30, and the light will not be absorbed by the light shielding part 30, especially in the part where the width (thickness) of the light shielding part is thin. This is not desirable because it allows the light to pass through. Furthermore, the higher the OD value, the higher the light absorption rate; however, when a photoreactive resin that hardens in response to light, such as an ultraviolet curable resin, is used as the base material of the resin material forming the light shielding part 30, If the OD value is larger than the above range, light is absorbed by the resin material and the resin material is not sufficiently cured when forming the light shielding part 30, which is not preferable.

The dimensions d1 and d2 satisfy d2≧d1, and in this embodiment, it is preferable that the dimension d1 is a numerical value within the range of 3 to 100 μm, and the dimension d2 is a numerical value within the range of 5 to 200 μm.
Further, in the present embodiment, the OD value at a portion having a thickness of dimension d1 (near the flat portion 32) is 1, and the OD value at a portion having a thickness of dimension d2 (second portion 34) is 2. It is.
Since the light to be blocked obliquely enters the first portion 33, even if the thickness (dimension d1) of the first portion 33 is small, the distance through which the light passes becomes long. Therefore, even if the OD value at the thinnest portion of the first portion 33 is small (even if the dimension d1 is small), light can be sufficiently absorbed. On the other hand, since light also enters the second portion 34 from the front direction, the light will not be absorbed and will leak unless the OD value is large (if the dimension d2 is not large enough). Therefore, the size relationship and OD value of the dimensions d1 and d2 are as described above.

It is desirable that the refractive index n2 of the light shielding portion 30 is greater than or equal to the refractive index n1 of the optically shaped layer 20 (n2≧n1). Thereby, among the light that passes through the unit optical shape 21, the light that is incident on the second surface 23, etc. can be made to enter the light shielding section 30 without being totally reflected, and can be reliably absorbed by the light shielding section 30.
As described above, when the light shielding part 30 is formed of a base material containing a coloring material, the refractive index n2 of the base material is set to be equal to or higher than the refractive index n1 of the optically shaped layer 20. It is possible to significantly suppress the total reflection of light incident on the surface 23 etc. of the light shielding part 30 at the interface between the base material of the light shielding part 30 and the unit optical shape 21, and the coloring material contained in the base material It is possible to reliably absorb the light incident on the surface 23 of No. 2, etc.

The light shielding part 30 of this embodiment uses a urethane acrylate-based ultraviolet curable resin (refractive index n2 = 1.53) as a base material, similar to the optically shaped layer 20, and black particles with an average particle size of about 3 μm as a coloring agent. It is formed using as.
Note that if the difference between the refractive index n1 of the optically shaped layer 20 and the refractive index n2 of the light shielding part 30 is too large, reflection at the refractive index interface will increase even if total reflection does not occur, so the difference should be 0.1 or less. It is desirable that there be. That is, it is desirable that the difference Δn (=n2−n1) between the refractive index n1 of the optically shaped layer 20 and the refractive index n2 of the light shielding part 30 satisfies 0≦Δn≦0.1.

The joining layer 40 is a part that joins the above-mentioned optically shaped layer 20 and light shielding part 30 to the second base layer 50, and is formed of a resin material having optical transparency. For the bonding layer 40, for example, the same material as the optical shape layer 20 described above can be used.
The second base material layer 50 is a sheet-like base material that forms the front side (+Z side) of the optical member 1, and is made of, for example, polyester resin such as PET (polyethylene terephthalate) having high light transmittance, acrylic resin, It is formed from styrene resin, acrylic styrene resin, PC (polycarbonate) resin, alicyclic polyolefin resin, TAC (triacetyl cellulose) resin, etc.

The second base layer 50, like the base layer 10 described above, is formed of a resin containing dark-colored pigments, dyes, particles, etc. such as gray or black as a coloring material, and has a light attenuation effect. It may have. In that case, the light transmittance of the second base layer 50 in the thickness direction (Z direction) is preferably 20 to 80%.
By adopting such a configuration, similar to the case where the base material layer 10 has a light attenuation effect described above, the transmitted light intensity can be adjusted, and when a small amount of light that should be blocked leaks, it can be , the effect of weakening such light and improving light shielding performance can be obtained.

In this embodiment, an example will be described in which the second base layer 50 does not have a light attenuation effect and only the base layer 10 has a light attenuation effect, but the present invention is not limited to this. The base layer 10 and the second base layer 50 may both have a light attenuation effect, or may have no light attenuation effect, or the second base layer 50 may have a light attenuation effect. It may have a light attenuation effect and the base layer 10 may have no light attenuation effect.
Further, the back surface of the base material layer 10 (-Z side surface) and the surface of the second base material layer 50 (+Z side surface) are coated with a hard coat layer or the like to prevent scratches, respectively. It may be provided as appropriate depending on the environment and the like. The hard coat layer is formed, for example, by applying an ultraviolet curable resin (for example, urethane acrylate) having a hard coat function.

Here, the unit optical shape 21 and the light shielding section 30 will be explained in more detail.
In the cross section of the unit optical shape 21 shown in FIG. As shown in FIG. 2, a straight line passing through the +X side of the first surface 22 closest to the +X side (straight line S2 shown by a dashed line in FIG. 7) is a point 25a that is the edge of the fourth surface 25 on the −X side (coinciding with the intersection of the fourth surface 25 and the fifth surface 26). The angle (second angle) that the straight line S2 makes with the thickness direction (Z direction) is defined as an angle θ3 [°].
The angles that the third surface 24 and the fifth surface 26 make with the thickness direction (Z direction) are both equal to or less than this angle θ3. Further, the angle θ3 is larger than the above-mentioned angle θ2.

It is desirable that the angle θ3 satisfies the relationship of formula (1) below, where n1 is the refractive index of the optical shape layer 20 (unit optical shape 21).
Formula (1) arcsin(1/n1)-5°≦θ3≦arcsin(1/n1)+5°
If the angle θ3 is smaller than the lower limit of equation (1), if light that is largely inclined toward the -X side when viewed from the optical member 1 is incident on the optical member 1, the third surface 24 or the fifth surface 26 and is absorbed by the light shielding part 30, which is undesirable because the amount of light transmitted through the optical member 1 decreases.

Further, when the angle θ3 is larger than the upper limit of equation (1), when attempting to form the unit optical shape 21 while maintaining the dimension h in the thickness direction (Z direction) of the second surface 23 or the angle θ4 described later In addition, the dimensions of the light shielding portions 30 in the arrangement direction (X direction) become large, and the area of the first surface 22 on the surface 20a of the optically shaped layer 20 becomes too small compared to the area of the surface 31 of the light shielding portion 30. . This is undesirable because the optical member 1 has a narrow opening through which light passes, and much of the light incident on the optical member 1 is blocked by the light shielding portion 30, reducing the amount of transmitted light.
From the above, it is desirable that the angle θ3 satisfies the above formula (1).

Next, in the cross section of the unit optical shape 21 shown in FIG. The angle (corresponding point) made with the thickness direction by a straight line (straight line S shown by a dashed-dotted line in FIG. 1 angle) is set to θ4 [°].
The angle θ4 is smaller than the critical angle of the unit optical shape 21 (optical shape layer 20) and smaller than the above-mentioned angle θ3 (θ4<θ3).
This angle θ4 is appropriately set depending on the incident angle of the light to be blocked and the refractive index n1 of the optically shaped layer 20.

Next, in the cross section of the optical member 1 shown in FIG. When b is the dimension in the arrangement direction of the surface 31 of the light shielding part 230 on the most surface side (+Z side) (contacting through the surface 23 of P becomes P=a+b.
In this embodiment, the arrangement pitch P of the light shielding parts 30 is constant. In this embodiment, the arrangement pitch P is preferably a value within the range of 50 to 1500 μm. Further, the dimension a is preferably a value within the range of 15 to 450 μm.

FIG. 3 is a diagram showing how light enters the optical member 1 of the first embodiment. 3, similar to FIG. 2, a part of the cross section parallel to the arrangement direction (X direction) of the unit optical shapes 21 and the thickness direction (Z direction) of the optical member 1 is shown in an enlarged manner. This shows the state of light at . Further, in FIG. 3, in order to facilitate understanding, it is assumed that there is no difference in refractive index at the interface between each layer in the optical member 1.

As shown in FIG. 1 described above, the optical member 1 of the present embodiment is provided in a skylight 120 of a building 100, and receives external light such as sunlight that enters from the skylight 120 from a specific angle. Block outside light. In this embodiment, an example is arranged such that the thickness direction (Z direction) of the optical member 1 corresponds to the vertical direction of the building 100, and the sheet surface (XY plane) of the optical member 1 corresponds to the horizontal direction. I will list and explain.
Further, the optical member 1 of the present embodiment is arranged such that the base layer 10 is located on the vertically lower side (−Z side), and light incident from a specific direction inclined toward the +X side when viewed from the optical member 1 In order to block the lights L6 to L8 shown in FIG. It is arranged so as to be located on the +X side.

Of the external light incident on the optical member 1, the light L1, which is a part of the light that is parallel or approximately parallel to the thickness direction (Z direction) of the optical member 1, is transmitted to the second base layer 50 and The light passes through the bonding layer 40 and enters the first surface 22 of the unit optical shape 21 of the optical shape layer 20 . Then, the light passes through the unit optical shape 21 and the base material layer 10 and is emitted toward the indoor side (-Z side).
On the other hand, among the lights parallel or substantially parallel to the thickness direction (Z direction) of the optical member 1, light L2 other than L1 passes through the second base layer 50 and the bonding layer 40, and is transmitted through the light shielding part 30. The light enters the surface 31 and is absorbed by the light shielding part 30.

Next, out of the external light that enters the optical member 1, lights L3 and L4, which are part of the light that enters from a direction tilted toward the −X side when viewed from the optical member 1, are used as the second The light passes through the base material layer 50 and the bonding layer 40 and enters the first surface 22 . It is assumed that the light L4 has a larger incident angle than the light L3.
The unit optical shape 21 protrudes toward the light shielding part 30 adjacent to the +X side of the straight line S2 forming an angle θ3 in the thickness direction (that is, the -X side surface of the light shielding part 30 is recessed toward the +X side of the straight line S2). Since this straight line S2 is inclined in the same direction as the lights L3 and L4, and the angle θ3 satisfies the above-mentioned formula (1), the lights L3 and L4 are composed of the third surface 24, etc. The light passes through the unit optical shape 21 and the base material layer 10 without entering the folded surface, and is emitted toward the indoor side (-Z side).
Further, among the light incident from a direction inclined to the -X side when viewed from the optical member 1, light L5, which is light other than light L3 and light L4, passes through the second base layer 50 and the bonding layer 40, The light enters the surface 31 of the light shielding section 30 and is absorbed by the light shielding section 30 .

Next, among the external light that enters the optical member 1, light L6, L7, and L8 that are part of the light that enters from a direction inclined to the +X side when viewed from the optical member 1 are transmitted to the second base layer 50 and The light passes through the bonding layer 40 and enters the first surface 22 . It is assumed that the incident angle of each light increases in the order of light L6, light L7, and light L8.
Here, for the lights L6 to L8, the angle between the direction in which they travel in the optically shaped layer 20 and the thickness direction is larger than the angle θ4, and the angle θ2 that the second surface 23 of the unit optical shape 21 makes with the thickness direction is the angle θ3. In this embodiment, the angle θ2=0°. Therefore, the lights L6 to L8 pass through the unit optical shape 21, enter the second surface 23, and are absorbed by the light shielding part 30.

On the other hand, light L9, which is a part of the light that is incident from a direction inclined to the +X side when viewed from the optical member 1 and has a smaller incident angle than the lights L6 to L8, is inside the optically shaped layer 20. The angle between the direction of travel and the thickness direction is smaller than the angle θ4. This light L9 passes through the optical shape layer 20 (unit optical shape 21) and the base material layer 10, and is emitted toward the indoor side (-Z side). Also, similar to the light L9, some of the light having a smaller incident angle than the lights L6 to L8 may be similar to the lights L6 to L8 depending on the incident position on the first surface 22, although not particularly shown. Then, the light enters the light shielding section 30 and is absorbed.
Further, among the light incident from a direction inclined to the +X side when viewed from the optical member 1, light other than the light L6 to L9 passes through the second base layer 50 and the bonding layer 40 and enters the light shielding part 30. The light L10 incident on the surface 31 is absorbed by the light shielding part 30.

Therefore, in the optical member 1, among the light incident on the optical member 1 from a direction inclined to the +X side, the direction in which the light travels within the unit optical shape 21 (the refraction angle into the optical shape layer 20) is larger than the angle θ4. Absorbs light (light L6 to L8) and blocks it.

From the above, the optical member 1 of the present embodiment allows light to enter from the front side (+Z side) in a plane (XZ plane) parallel to the arrangement direction of the unit optical shapes 21 and the light shielding parts 30 and the thickness direction of the optical member 1. Of the light, a part of the light incident from the thickness direction or the direction tilted to -X is absorbed (light L2 shown in FIG. 3), and the rest is transmitted (light L1, light L3, shown in FIG. 3). Light L4).
In addition, the optical member 1 has a specific direction for light incident from a direction inclined to the + Light incident from directions (angular range) (lights L6 to L8 shown in FIG. 3) is blocked, and light incident from directions other than a specific direction (angular range) is partially transmitted (light L9 shown in FIG. 3). ). Further, regardless of the incident angle, part of the light that enters the surface 31 from the direction inclined to the +X side is blocked (light L10 shown in FIG. 3). The light shielding part 30 of the optical member 1 of this embodiment has an OD value set optimally according to the dimensions d1 and d2, which are the thicknesses (widths) of the first part 33 and the second part, and the OD value is set optimally according to the thickness (width) of the first part 33 and the second part. The transmittance of light (lights L6 to L8 shown in FIG. 3) through the optical member 1 can be significantly suppressed.

Therefore, the optical member 1 can block light from a specific direction (angular range) and prevent it from being emitted indoors as much as possible, and can also transmit most of the light that enters from other directions. Therefore, the brightness in the room can be maintained.

Next, an example of a method for manufacturing the optical member 1 will be described. Note that the method for manufacturing the optical member 1 is not limited to the following manufacturing method.
First, the base material layer 10 is prepared, and a mold for shaping the unit optical shape 21 is laminated on one side with an ultraviolet curable resin filled therein, and the ultraviolet curable resin is cured by irradiating ultraviolet rays. The optically shaped layer 20 is formed by a UV molding method.

Next, on the formed optical shape layer 20, a resin material containing a coloring material to form the light shielding part 30 is applied, and by wiping (squeezing), the resin material is applied to the valleys of the adjacent unit optical shapes 21. At the same time, excess resin is removed. Then, by curing the filled resin material, a light shielding part 30 is formed between the valleys of adjacent unit optical shapes 21. In this embodiment, as the base material of the resin material, an ultraviolet curable resin similar to the unit optical shape 21 (optical shape layer 20) and having a refractive index 0.1 higher is used.

FIG. 8 is a diagram illustrating the optical member 9 of a comparative example. FIG. 8 shows an enlarged cross section of an optical member 9 of a comparative example, which corresponds to the cross section of the optical member 1 of the present embodiment shown in FIG. 2 described above.
The optical member 9 of the comparative example has the same form as the optical member 1 of the present embodiment, except that the cross-sectional shape of the light shielding part 930 is wedge-shaped. Therefore, the same reference numerals or the same suffixes are given to parts that perform the same functions, and redundant explanations are omitted as appropriate.
In the optical member 9 of the comparative example, the unit optical shape 921 has a second surface 923 on the -X side of the first surface 922, and a second surface 923 on the +X side of the first surface 922, which is inclined toward the -X side. 3 faces 924. The angle that the second surface 923 makes with the thickness direction is angle θ2, which is equal to angle θ2 in this embodiment. Since the angle θ2 is 0°, the angle θ2 is omitted in FIG. 8 . The angle that the third surface 924 makes with the thickness direction is angle θ3, which is equal to angle θ3 in this embodiment. This light shielding portion 930 has an asymmetric wedge shape.

The optical member 9 of this comparative example is an optical member that performs the same light control function as the optical member 1 of this embodiment in terms of optical design.
In the light shielding part 930 of the comparative example, when a photoreactive resin such as an ultraviolet curable resin containing a coloring material is used as the base material of the resin material forming the light shielding part 930, as in the present embodiment, the surface side ( Since there is a large difference in the thickness (dimension in the X direction) of the light shielding part 930 between the +Z side) and the back side (-Z side), increasing the OD value of the resin material will ensure sufficient hardening in the thicker part. This results in uneven curing, which deteriorates the quality of the optical member. Furthermore, if the OD value of the resin material is lowered, curing unevenness can be suppressed, but the light incident on the thinner part (the tip on the back side) is transmitted through the light shielding part 930 and emitted without being absorbed. Light blocking performance deteriorates.

On the other hand, in the present embodiment, the OD value is 1 in the portion of the light shielding portion 30 whose thickness is the dimension d1 (near the flat portion 32 of the first portion 33), and the OD value is 1 in the portion where the thickness is the dimension d2. The OD value at (second portion 34) is 2. Therefore, the light shielding portion 30 can be sufficiently cured, and the optical member 1 can absorb the incident light and sufficiently shield the light, thereby providing the optical member 1 with high light shielding performance.
Furthermore, since the light shielding part 30 of this embodiment has smaller changes in the thickness (width) of each part than the wedge-shaped light shielding part 930 shown in FIG. Quality can be improved.

Therefore, according to the present embodiment, when curing the resin material of the light shielding part 30 by irradiating ultraviolet rays, even if a resin material with a high OD value (light absorption rate) is used, it cannot be sufficiently cured. Even if light is incident on a thin portion, such as the tip of the back side (-Z side) of the first portion 33, the light can be sufficiently absorbed and the light control function can be enhanced. Furthermore, according to the present embodiment, it is possible to suppress curing unevenness due to thickness, facilitate formation of the light shielding portion 30, and provide a high-quality optical member 1.
Furthermore, at this time, the first surfaces 22 of the unit optical shapes 21 of this embodiment are at the same position in the thickness direction (Z direction) and are located on the same plane parallel to the XZ plane, so squeezing is easy. can be done.

Note that the light shielding portion 30 may be formed by repeating filling and curing the resin material into the valleys of adjacent unit optical shapes 21 multiple times. Thereby, even if a strain occurs on the surface of the light shielding part 30 during the curing process of the resin material, the strain can be further reduced.
Further, the light shielding part 30 may be cured by irradiating ultraviolet rays not only from one side of the optically shaped layer 20 but also from both sides (the +Z side surface and the -Z side surface). At this time, one side may be irradiated alternately, or both sides may be irradiated simultaneously. Thereby, the light shielding part 30 can be more fully cured.

Subsequently, the bonding material for the bonding layer 40 is applied to the surfaces of the unit optical shapes 21 and the light shielding portions 30, the second base layer 50 is bonded thereon, and the bonding material is cured to form an optical member. 1 is completed.
The bonding material used for the bonding layer 40 is preferably the same material as the optical shape layer 20 from the viewpoint of suppressing refraction of light between the unit optical shape 21 and the bonding layer 40.

From the above, according to this embodiment, the optical member 1 has the following effects.
(1) In the arrangement direction (X direction) of the unit optical shape 21 and the light shielding part 30, the optical member 1 transmits light in a specific direction (incidence angle range) among the incident light to the light shielding part 30 through the second surface 23. While blocking light, it is possible to transmit most of the light from other directions, including light incident from the opposite side.

(2) In the optical member 1, the light shielding part 30 has a first part 33 and a second part 34, and has a so-called L-shaped cross section, and a light shielding part having a wedge-shaped cross section (as shown in FIG. Compared to the light shielding part 430) of the comparative example, the change in dimensions (width) of each part is small. Therefore, an ultraviolet curable resin similar to that of the unit optical shape 21 (optical shape layer 20) is used as the resin material, and its OD value is 0.5 to 2 at the part where the thickness is the dimension d1, and the OD value is 0.5 to 2 at the part where the thickness is the dimension d2. Even when the thickness is increased from 1 to 3 in a certain portion, the light shielding part 30 can be sufficiently cured, uneven curing due to the difference in thickness can be suppressed, and the light shielding part 30 can be easily formed. In addition, since the OD value of the resin material can be increased, even if light is incident on thin parts such as the tip of the back side (-Z side) of the first part 33, it can sufficiently absorb the light and prevent leakage light. This can be significantly reduced and the light shielding performance can be improved.

(3) In the optical member 1, since the first surface 22 of the unit optical shape 21 and the surface 31 of the light shielding part 30 are at the same position in the thickness direction (Z direction), the formation of the light shielding part 30 is easy and mass production is possible. It is possible.

(4) In the optical member 1, the angle θ3 [°] satisfies arcsin(1/n1)-5°≦θ3≦arcsin(1/n1)+5°, where n1 is the refractive index of the optically shaped layer 20. , and for angle θ2, θ3>θ2 is satisfied. As a result, the optical member 1 blocks light incident from a specific direction, and the opposite side of the specific direction (in the arrangement direction), which was blocked by conventional optical members having a light blocking part with a rectangular cross-sectional shape or the like. It is possible to transmit light incident from an angular range corresponding to the opposite side), and the amount of transmitted light transmitted through the optical member 1 can be maintained appropriately.

(5) In the optical member 1, since the refractive index n2 of the light shielding part 30 is greater than or equal to the refractive index n1 of the optical shape layer 20 (unit optical shape 21), the second surface of the light transmitted through the unit optical shape 21 It is possible to reliably absorb the light incident on 23 etc. in the light shielding part 30 without causing total reflection.

(Second embodiment)
FIG. 4 is a diagram illustrating the optical member 2 of the second embodiment. FIG. 4 shows an enlarged view of a part of a cross section parallel to the thickness direction (Z direction) of the optical member 2 and parallel to the arrangement direction (X direction) of the unit optical shape 221 and the light shielding part 230. Note that in FIG. 4, only the optically shaped layer 220 is shown. The illustration of the base material layer 10, bonding layer 40, and second base material layer 50 that constitute the optical member 2 is omitted.
The optical member 2 of the second embodiment has the same form as the first embodiment described above, except that the forms of the optical shape layer (unit optical shape) and the light shielding part are different. Therefore, the same reference numerals or the same reference numerals at the end are given to parts that perform the same functions as those in the first embodiment described above, and redundant explanations will be omitted as appropriate.

In the cross section of the optical member 2 (optical shape layer 220) shown in FIG. 4, the unit optical shape 221 of this embodiment has a first surface 22 and a a second surface 23 located on the −X side of the first surface; and a third surface 24 forming a folded surface provided on the +X side of the first surface and opposite to the second surface 23. , a fourth surface 25, and a fifth surface 26.
As shown in FIG. 4, the plurality of arranged unit optical shapes 221 have similar cross-sectional shapes, but their sizes are not constant.

The light shielding part 230 is formed in a valley between adjacent unit optical shapes 221, and in the cross section of the optical member 2 shown in FIG. It has an L-shape including an extending first portion 33 and a second portion 34 extending from the surface side (+Z side) end of the first portion 33 toward the -X side.
As shown in FIG. 4, the plurality of arranged light shielding parts 30 have similar cross-sectional shapes, but their sizes are not constant.
Further, the light shielding portion 230 has OD values set at the dimensions d1 and d2, similarly to the first embodiment. In this embodiment, the sizes of the arranged light shielding parts 230 are not constant, so the dimensions d1 and d2 of each light shielding part 230 are different. Therefore, the OD value in the dimension d1 and the OD value in the dimension d2 are different for each light shielding part 230, but are appropriately set to satisfy the range of 0.5 to 2 and the range of 1 to 3, respectively.

Here, the unit optical shape 221 and the light shielding section 230 will be explained in more detail.
As described above, the arranged plurality of unit optical shapes 221 have similar cross-sectional shapes, and their sizes are not constant. Moreover, the plurality of light shielding parts 230 arranged in the array also have similar cross-sectional shapes, and their sizes are not constant.
Therefore, the angles θ1 and θ2 that the first surface 22 and the second surface 23 make with the thickness direction (Z direction) are constant in the arrangement direction (X direction) of the unit optical shapes 221 and the light shielding parts 230.

Also, in this embodiment, the angle θ4 is a straight line (shown by a dashed line in FIG. This is the angle that the straight line S) makes with the thickness direction (Z direction). This angle θ4 is constant in the arrangement direction of the unit optical shapes 221 and the light shielding portions 230, regardless of the sizes of the unit optical shapes 221 and the light shielding portions 230. Further, as in the first embodiment, the angle θ4 is smaller than the critical angle of the unit optical shape 221 (optical shape layer 220) and smaller than the angle θ3 (θ4<θ3).

Furthermore, since the angle θ4 in the arrangement direction (X direction) of the unit optical shapes 21 is constant, in the cross section of the optical member 2 shown in FIG. The ratio a/h between the dimension a of the unit optical shape 21 and the dimension h in the thickness direction (Z direction) of the light shielding part 230 adjacent to the second surface 23 side (-X side) of the unit optical shape 21 is also determined by the unit optical shape 221. is constant regardless of the size of the unit optical shape 221 and the light shielding part 230 in the arrangement direction. This ratio a/h has a value according to the angle θ4.

Further, in the cross section of the optical member 2 shown in FIG. 4, the dimension in the arrangement direction of the first surface 22 of the unit optical shape 221 is a, and the surface of the light shielding part 230 adjacent to the −X side of the unit optical shape 221 31 in the arrangement direction is b, and the arrangement pitch of the light shielding parts 230 (that is, the arrangement pitch of the unit optical shapes 221) P is P=a+b.
As described above, in this embodiment, the sizes of the cross-sectional shapes of the unit optical shapes 21 and the light shielding parts 230 are not constant, so the dimensions a and b are also not constant in the arrangement direction of the unit optical shapes 21 and the light shielding parts 230. . Therefore, the arrangement pitch P is not constant in the arrangement direction (X direction) of the light shielding parts 230 and the unit optical shapes 221.
In this embodiment, the arrangement pitch P is a value within the range of 50 to 1500 μm, and the dimension a is a value within the range of 15 to 450 μm.

In this way, in the arrangement direction of the optical member 1, although the arrangement pitch P of the light shielding parts 30 (the arrangement pitch of the unit optical shapes 221) is not constant, the angles θ2, θ3, and θ4 are constant, and the optical member 2 is The incident angle range of the light to be blocked can be kept constant in the arrangement direction while suppressing the diffraction phenomenon caused by the transmitted light.
Further, since the first surface 22 and the surface 31 are located on the same plane (on one surface 220a of the optically shaped layer 20) in the thickness direction (Z direction), the light control function of the optical member 2 varies in the arrangement direction. Never.

In addition, in the cross section of the optical member 2 shown in FIG. The ratio a/b of 230 to the dimension b of the surface 31 is determined by the unit optical shape 221 and the light shielding part 230 because the unit optical shape 221 and the light shielding part 230 are similar in the arrangement direction of the unit optical shape 221 and the light shielding part 230, respectively. It is constant regardless of the size of the light shielding part 230.
As a result, the optical member 1 can maintain a constant light transmittance in the arrangement direction (X direction) of the unit optical shapes 21 and the light shielding parts 30, and can significantly reduce unevenness in brightness depending on the location on the optical member 1. can be suppressed to

From the above, according to the present embodiment, the optical member 2, like the optical member 1 of the first embodiment, blocks incident light from a specific direction (angular range) and blocks light from other directions. It is possible to transmit much of the light, and it is also possible to perform a high light control function. Further, according to the present embodiment, the optical member 2 can sufficiently harden the light shielding portion 230 and is easy to manufacture, similarly to the optical member 1 of the first embodiment.

Further, according to the present embodiment, the optical member 2 has a constant angle θ4 (ratio a/h) in the arrangement direction of the unit optical shape 221 and the light shielding parts 230, and the arrangement pitch P of the light shielding parts 230. is not constant, it is possible to suppress the diffraction phenomenon caused by light passing through the optical member 2. As a result, ghost images caused by diffraction phenomena can be suppressed, and when observing the other side (outside in this embodiment) through the optical member 2, the scenery does not blur or become blurred, providing comfortable visibility. be able to.

In conventional optical members equipped with light-shielding parts with rectangular cross-sectional shapes, when the arrangement pitch of the light-shielding parts is not constant in order to suppress diffraction phenomena, the angular range of light to be blocked changes as the arrangement pitch changes. However, variations in light control function occur and quality deteriorates. In addition, in conventional optical members, when the arrangement pitch of the light shielding parts is increased in order to suppress the diffraction phenomenon, it is necessary to increase the thickness direction of the light shielding parts in order to maintain the light control function. The thickness may increase, or the light shielding portion may appear streaky.

On the other hand, in the optical member 2, the arrangement pitch P of the light shielding parts 230 is not constant in the arrangement direction (X direction) of the unit optical shape 221 and the light shielding part 230, and the angle θ4 (ratio a/h) is Since it is constant, the angle of incidence of the light to be blocked can be kept constant in the arrangement direction of the light blocking portion 230 while suppressing the diffraction phenomenon, and the light control function of the optical member 2 will not vary in the arrangement direction. , can demonstrate high light control function.
In addition, the optical member 2 suppresses the diffraction phenomenon by making the arrangement pitch P of the light shielding parts 230 not constant, and in order to suppress the diffraction phenomenon while maintaining the light control function, the arrangement pitch P is changed. There is no need to increase the size of the light shielding part 230 in the thickness direction (Z direction) accordingly, and the thickness of the optical member 2 can be made thinner than that of the conventional one.

Further, according to the present embodiment, the optical member 2 has the dimension a of the first surface 222 and the second surface of the unit optical shape 221 in the arrangement direction (X direction) of the unit optical shape 221 and the light shielding part 230. Since the ratio a/b of the dimension b of the surface 31 of the light shielding part 230 adjacent to the 23 side (-X side) is constant, the optical member 2 can be The transmittance of the transmitted light is constant in the arrangement direction of the unit optical shapes 221 and the light shielding parts 230, and unevenness in brightness depending on the location on the optical member 2 can be significantly suppressed.

(Deformed form)
Various modifications and changes are possible without being limited to the embodiments described above, and these are also within the scope of the embodiments of the present disclosure.

(1) In each embodiment, an example has been shown in which the optically shaped layer and the base material layer are formed from separate members, but the invention is not limited to this, and the optically shaped layer and the base material layer are formed from the same member. They may be integrally formed. Thereby, a refractive index interface is formed between the base material layer and the optically shaped layer, and it is possible to avoid refraction of incident light between both layers.

(2) In each of the embodiments, the base material of the resin material forming the light-shielding portion has been described using an ultraviolet curable resin, but it is not limited to this, and examples include polyester resin such as PET, acrylic resin, styrene resin, Acrylic styrene resin, PC resin, alicyclic polyolefin resin, TAC resin, MS (methacrylic styrene) resin, MBS (methacrylic butadiene styrene) resin, etc. may be used. Even when such a resin is used, by forming the light shielding part in the shape of each embodiment, the light shielding part can be sufficiently cured, and the optical member can be manufactured easily.

(3) In each embodiment, the optical member 700 may be formed in the form of a laminated glass by sandwiching the optical member between two transparent base materials 70, 71, for example, glass substrates.
FIG. 5 is a diagram showing a modified form of the optical member. Similar to FIG. 1, etc., FIG. 5 shows a cross section of the optical member 700 (optical member 1) parallel to the XZ plane, the optical shape layer 20 is simplified, and the unit optical shape and the light shielding part are omitted. It shows.
In this case, transparent bonding materials 72 and 73 (for example, PVB, etc.) are provided between the optical member 1 and each transparent base material 70 and 71, and the optical member 1 and each transparent base material 70 and 71 are bonded together. be done.
Further, the base material layer 10 and the second base material layer 50 may each be replaced with a transparent base material (glass substrate) to form a laminated glass-like optical member. Thereby, the layer structure of the laminated glass-like optical member can be further simplified, manufacturing costs can be reduced, and manufacturing efficiency can be improved.
Here, an example is shown in which the optical member 1 of the first embodiment is sandwiched between the transparent base materials 70, 71 and the transparent bonding materials 72, 73, but the present invention is not limited to this, and optical members of other embodiments may be used. It's okay.

(4) In each embodiment, in a cross section (XZ plane) parallel to the arrangement direction and thickness direction of the unit optical shape and the light shielding part, the +X side surface of the unit optical shape opposite to the second surface is the third surface. Although the example is shown in which the folded surface is composed of a surface, a fourth surface, and a fifth surface, the unit optical shape is not limited to this, for example, the surface on the +X side opposite to the second surface is on the light shielding part side. It may also have a curved surface that is convex. In this case, the cross-sectional shape of the light shielding portion is concave on the −X side.
FIG. 6 is a diagram illustrating a modified form of the optical member. FIG. 6 shows a cross section parallel to the arrangement direction of the unit optical shape 321 and the light shielding part 330 and the thickness direction of the optical member 3. Here, a modification of the optical member 1 of the first embodiment will be described as an example, but a similar modification is possible for the optical member 2 of the second embodiment.
As shown in FIG. 6, in the modified optical member 3, the +X side of the unit optical shape 321 is a curved surface 327 that is convex toward the light shielding portion 330 adjacent to the +X side. Therefore, the light shielding part 330 has a concave shape on the -X side. Even with such a configuration, the same effects as in the first embodiment and the like described above can be achieved.

(5) In each embodiment, the light-shielding portion is separated from the second portion 34 from the surface side (+Z side) end of the first portion 33 in a cross section parallel to the unit optical shape and the arrangement direction and thickness direction of the light-shielding portion. It may have a convex portion that protrudes along the surface 20a toward the opposite side, that is, the +X side.
FIG. 7 is a diagram showing a modified form of the optical member. FIG. 7 shows a cross section parallel to the arrangement direction of the unit optical shape 21 and the light shielding part 430 and the thickness direction of the optical member 4. Here, a modification of the optical member 1 of the first embodiment will be described as an example, but a similar modification is possible for the optical member 2 of the second embodiment.

As shown in FIG. 7, the light shielding part 430 of the modified optical member 4 has a convex part 435. This convex portion 435 constitutes the surface 31 of the light shielding portion 430, and is convex toward the +X side along the surface 20a of the optically shaped layer 20. The convex portion 435 can absorb the light L40 that would otherwise be reflected at the interface between the light shielding portion 430 and the unit optical shape 421 (optical shape layer 20) and transmitted through the optical member 4. . Therefore, when light such as the light L40 passes through the optical member 4 and produces a ghost image, it is possible to prevent the scenery from blurring or becoming blurred when the other side is observed through the optical member 4.

When having such a convex portion 435, it is particularly preferable that the light shielding portion 430 uses dark-colored particles such as gray or black as a coloring material, but is not limited to this, and dyes shown in each embodiment are used. Other coloring materials such as pigments and pigments may also be used.
Although the convex portion 435 has a triangular cross-sectional shape in the cross-section of the optical member 4 shown in FIG. The convex portion 435 may have a circular shape or the like, or the convex portion 435 may have a shape in which the back surface side (-Z side) is formed by a curved surface.

(6) In each embodiment, the second surface 23 may be a rough surface having fine irregularities. By adopting such a configuration, it is possible to prevent a portion of the light that is incident on the light shielding portion and is desired to be blocked from being reflected by the second surface 23 and transmitted through the optical member, thereby suppressing the deterioration of the light control function.

(7) In each embodiment, one layer having necessary functions such as antireflection function, ultraviolet absorption function, antifouling function, antistatic function, etc. is provided depending on the usage environment and purpose of the optical member. Alternatively, a plurality of them may be selected and provided on the optical member.

(8) In each embodiment, the light shielding part has a light reflection property on its surface side (+Z side, opposite side to the base material layer 10), and has a light absorption property on a surface in contact with the unit optical shape. You can do it like this. In other words, the light-shielding part has a structure in which a light-reflecting part having a light-reflecting property and a light-absorbing part having a light-absorbing property are laminated in order from the front side (+Z side), and the surface on the front side of the light-shielding part has a light-reflecting part. Most of the surface of the light shielding section that is in contact with the unit optical shape may be formed of the light absorption section. Note that in the case of a light shielding part having a flat part, the flat part is formed by a light absorbing part.

With this, for example, when sunlight is incident on the surface of the optical member, the sunlight can be reflected by the light reflecting section located on the surface side (+Z side) of the light shielding section, and the sunlight can be reflected by the light shielding section. heating of the optical member can be significantly suppressed, and the durability of the optical member against heat can be improved.
Such a light shielding portion can be formed, for example, as follows.
First, a resin material forming a light absorbing portion is filled in the valley between the unit optical shapes 21 by wiping or the like, and is hardened. At this time, the resin material forming the light absorbing portion is filled up to both edges of the valley, but is filled so as to form a depression in the center of the surface between the edges.

Next, a resin material for forming a light reflecting portion is filled into this depression by wiping or the like, and is cured. In addition, the resin containing the light reflecting material described in the above-mentioned modification (1) can be used as appropriate for the light reflecting portion. Through the above steps, the light shielding section 30 in which the light reflecting section and the light absorbing section are laminated in order from the front side is manufactured.

(9) In the first embodiment, the angles θ1, θ2, θ3, and θ4 are each constant over the entire surface of the optical member 1, but the angles are not limited to this, and vary depending on the position in the arrangement direction. may be set at different angles.
Furthermore, in the second embodiment, the angles θ1, θ2, and θ3 are each constant over the entire surface of the optical member 2. It may be set at an angle. Furthermore, in the second embodiment, the angle θ4 may be changed for each area on the optical member 2 depending on the usage purpose, usage environment, etc. of the optical member 2. For example, the angle θ4 of a certain region A (not shown) on the optical member 2 is different from the angle θ4 of a region B (not shown) adjacent to that region, but the angle θ4 in each region is the arrangement of the unit optical shapes 221. It may be constant in the direction (X direction). With this configuration, when the direction (incidence angle) of the light to be blocked differs depending on the area on the optical member 2, the transmission of the incident light can be appropriately restricted.

(10) In the second embodiment, a group consisting of a plurality of unit optical shapes 221 and light shielding parts 230 may be arranged repeatedly. In this case, the width of one group in the arrangement direction, that is, the arrangement pitch of the groups, is preferably 0.5 mm or more from the viewpoint of suppressing the diffraction phenomenon. If the arrangement pitch of the groups is less than 0.5 mm, it is not preferable because a diffraction phenomenon tends to occur.
By adopting such a configuration, the mold for the optically shaped layer 220 can be easily manufactured, and the optical member 1 can be manufactured more easily.

(11) In each embodiment, the optical member has been described using an example in which the second base layer 50 side is the light incident side in the thickness direction (Z direction); It may also be used as the incident side. Even if the optical member is used in this form, similar light control effects can be obtained.

In addition, although each embodiment and modification can also be used in combination suitably, detailed description is abbreviate|omitted. Furthermore, the present invention is not limited to the embodiments described above.

1, 2 Optical member 10 Base material layer 20, 220 Optical shape layer 20a, 220a One surface 21, 221 Unit optical shape 22 First surface 23 Second surface 24 Third surface 25 Fourth surface 26 Fifth surface Surface 30, 230 Light shielding portion 31 Surface 32 Flat portion 33 First portion 34 Second portion 40 Bonding layer 50 Second base layer 100 Building 120 Skylight

Claims (8)

An optical member that blocks incident light from a specific angle range,
an optical shape layer having optical transparency and having a plurality of unit optical shapes arranged on one surface;
a light shielding section provided between the adjacent unit optical shapes and shielding incident light;
Equipped with
In a cross section parallel to the arrangement direction of the unit optical shapes and parallel to the thickness direction of the optical member,
The light shielding part has a first part extending along the thickness direction, and a second part extending from the one surface side end of the first part to one side in the arrangement direction, and the second part extends in the arrangement direction. It has an asymmetrical shape,
The unit optical shape is closer to the light shielding part than a virtual straight line passing through a point on the one side of the tip of the first part and a point on the opposite side of the one surface of the tip of the second part. It stands out,
In the first part, the dimension at the part where the dimension in the arrangement direction of the unit optical shapes is the smallest is d1 [μm], and in the said second part, the dimension at the part where the dimension in the thickness direction of the optical member is the smallest is d2 When [μm], d1≦d2, the OD value at dimension d1 is 0.5 or more and 2 or less, and the OD value at dimension d2 is 1 or more and 3 or less.
Optical components. The optical member according to claim 1 ,
The base material layer is an optical member having a light transmittance of 20% or more and 80% or less in the thickness direction. The optical member according to claim 1 or 2 ,
The unit optical shape is
A cross-sectional shape in a cross section parallel to the arrangement direction of the unit optical shapes and parallel to the thickness direction of the optical member is a polygonal shape,
a first surface located on the one surface, into which light passing through the optical member enters or exits;
a second surface that forms an angle that is parallel or can be considered parallel to the thickness direction of the optical member, and whose edge on the one surface side coincides with one end of the first surface;
three surfaces located on the other side of the first surface and forming a folded surface facing the second surface, a third surface located on the back side and inclined with respect to the thickness direction; , a fourth surface located on the one surface side of the third surface and forming an angle that is parallel or can be considered parallel to the sheet surface; and a fourth surface located on the one surface side of the fourth surface, the optical a fifth surface inclined with respect to the thickness direction of the member;
The first angle that a straight line passing through the other end of the first surface of the unit optical shape and the edge of the second surface opposite to the one surface side makes with the thickness direction of the optical member is ,
smaller than the critical angle in the unit optical shape,
A straight line passing through the edge of the third surface on the opposite side to the one surface in the thickness direction of the optical member and the edge of the fourth surface on the fifth surface side is the optical member. An optical member that is smaller than the second angle formed with the thickness direction of the optical member. The optical member according to claim 3 ,
the first angle is constant in the arrangement direction of the unit optical shapes, and
An optical member in which the arrangement pitch of the light shielding parts in the arrangement direction of the unit optical shapes is not constant. The optical member according to claim 3 or 4,
When the second angle is θ3 and the refractive index of the unit optical shape is n1,
arcsin(1/n1)-5°≦θ3≦arcsin(1/n1)+5°
satisfies the formula
Optical components. The optical member according to any one of claims 1 to 5,
The light shielding portion is an optical member having a larger refractive index than the unit optical shape. The optical member according to any one of claims 1 to 6,
The light shielding part has a light reflecting part having a light reflecting property on a surface on the one side, and a light absorbing part having a light absorbing property on a surface in contact with the unit optical shape, and these parts are arranged in the thickness direction. Laminated form
Optical components. A window comprising the optical member according to any one of claims 1 to 7 .

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