JP2021004907A - Control device of light distribution device, light distribution system and light distribution control method - Google Patents

Abstract

To provide a control device of a light distribution device capable of enhancing security.SOLUTION: A control device 10 of a light distribution device 100 includes: an acquisition part 20 for acquiring time information showing time; and a control part 22 for controlling the light distribution device 100 provided with a light distribution layer 130 for distributing incident light on the basis of the time information. The light distribution layer 130 includes an irregularity layer 131 having a plurality of protrusions 133, and a variable refractive index layer 132 arranged so as to fill spaces among the protrusions 133 to change a refractive index according to a given electric field. The control part 22 has a first mode for generating a first reflective index difference in an interface between the plurality of protrusions 133 and the variable refractive index layer 132, and a second mode for generating a second refractive index difference larger than the first refractive index difference in the interface between the plurality of protrusions 133 and the variable refractive index layer 132, and executes the second mode in the case where a time shown by the time information is included in a night time.SELECTED DRAWING: Figure 1

Description

The present invention relates to a control device for a light distribution device, a light distribution control system, and a light distribution control method.

Conventionally, an optical device capable of changing the transmission state of incident light is known.

For example, Patent Document 1 describes a liquid crystal optical element having a pair of transparent substrates, a pair of transparent electrodes formed on each of the pair of transparent substrates, and a prism layer and a liquid crystal layer sandwiched between the pair of transparent electrodes. It is disclosed. The liquid crystal optical element changes the refractive index of the liquid crystal layer by a voltage applied to the pair of transparent electrodes, and changes the refraction angle of light passing through the interface between the slope of the prism and the liquid crystal layer.

Japanese Unexamined Patent Publication No. 2012-173534

The conventional liquid crystal optical element may be applied to, for example, a window. For this reason, it is expected that the liquid crystal optical element will be in a highly secure state in which the inside cannot be seen from the outside in consideration of privacy as well as daylighting.

Therefore, an object of the present invention is to provide a control device for a light distribution device, a light distribution control system, and a light distribution control method that can enhance security.

In order to achieve the above object, the control device of the light distribution device according to one aspect of the present invention includes an acquisition unit that acquires time information indicating the time and a light distribution that distributes incident light based on the time information. The light distribution layer includes a control unit that controls a light distribution device including the layer, and the light distribution layer is arranged so as to fill between the uneven layer having a plurality of convex portions and the plurality of convex portions, and responds to an applied electric field. The control unit includes a first mode in which a first refractive index difference is generated at an interface between the plurality of convex portions and the variable refractive index layer, and the plurality of said control units. When the interface between the convex portion and the variable refractive index layer has a second mode in which a second refractive index difference larger than the first refractive index difference is generated and the time indicated by the time information is included at night, the said Execute the second mode.

Further, the light distribution control system according to one aspect of the present invention includes the control device for the light distribution device and the light distribution device.

Further, the light distribution control method according to one aspect of the present invention includes a light distribution device including an acquisition step for acquiring time information indicating a time and a light distribution layer for distributing incident light based on the time information. The light distribution layer includes a control step for controlling, and the light distribution layer is arranged so as to fill between the uneven layer having a plurality of convex portions and the plurality of convex portions, and the refractive index changes according to an applied electric field. A first mode in which a variable index layer is provided and a first refractive index difference is generated at the interface between the plurality of convex portions and the variable refractive index layer, and the plurality of convex portions and the variable refractive index are provided. When the second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface with the layer is selectively executed and the time indicated by the time information is included at night, the second mode is performed. Execute.

Further, one aspect of the present invention can be realized as a program for causing a computer to execute the above light distribution control method. Alternatively, it can be realized as a computer-readable recording medium in which the program is stored.

According to the present invention, it is possible to provide a control device for a light distribution device, a light distribution control system, and a light distribution control method that can enhance security.

It is a block diagram which shows the structure of the light distribution control system which concerns on Embodiment 1. FIG. It is sectional drawing of the light distribution device which concerns on Embodiment 1. FIG. It is an enlarged sectional view of the light distribution device which concerns on Embodiment 1. FIG. It is an enlarged sectional view for demonstrating the lighting mode of the light distribution device which concerns on Embodiment 1. FIG. It is an enlarged sectional view for demonstrating the transparent mode of the light distribution device which concerns on Embodiment 1. FIG. It is an enlarged sectional view for demonstrating the security mode of the light distribution device which concerns on Embodiment 1. FIG. It is a flowchart which shows the control method of the light distribution device which concerns on Embodiment 1. FIG. It is a block diagram which shows the structure of the light distribution control system which concerns on Embodiment 2. It is a flowchart which shows the control method of the light distribution device which concerns on Embodiment 2. It is a block diagram which shows the structure of the light distribution control system which concerns on Embodiment 3. It is a flowchart which shows the control method of the light distribution device which concerns on Embodiment 3. It is a block diagram which shows the structure of the light distribution control system which concerns on Embodiment 4. FIG. It is a flowchart which shows the control method of the light distribution device which concerns on Embodiment 4. It is sectional drawing of the light distribution device which concerns on Embodiment 5. FIG. 5 is an enlarged cross-sectional view of the light distribution device according to the fifth embodiment. It is an enlarged sectional view for demonstrating the lighting mode of the light distribution device which concerns on Embodiment 5. It is an enlarged sectional view for demonstrating the transparent mode of the light distribution device which concerns on Embodiment 5. It is an enlarged sectional view for demonstrating the security mode of the light distribution device which concerns on Embodiment 5.

Hereinafter, the control device, the light distribution control system, and the light distribution control method of the light distribution device according to the embodiment of the present invention will be described in detail with reference to the drawings. In addition, all the embodiments described below show a specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement and connection forms of the components, steps, the order of steps, etc. shown in the following embodiments are examples, and are not intended to limit the present invention. Therefore, among the components in the following embodiments, the components not described in the independent claims indicating the highest level concept of the present invention will be described as arbitrary components.

Further, each figure is a schematic view and is not necessarily exactly illustrated. Therefore, for example, the scales and the like do not always match in each figure. Further, in each figure, substantially the same configuration is designated by the same reference numerals, and duplicate description will be omitted or simplified.

Further, in the present specification and the drawings, the x-axis, the y-axis, and the z-axis indicate the three axes of the three-dimensional Cartesian coordinate system. In each embodiment, the z-axis direction is the vertical direction, and the direction perpendicular to the z-axis (the direction parallel to the xy plane) is the horizontal direction. The positive direction of the z-axis is vertically above. Further, in the present specification, the "thickness direction" means the thickness direction of the optical device, and is the direction perpendicular to the main surfaces of the first substrate and the second substrate, and the "planar view" is the first. It means when viewed from the direction perpendicular to the main surface of the 1st substrate or the 2nd substrate.

(Embodiment 1)
[Light distribution control system]
First, the configuration of the light distribution control system 1 according to the present embodiment will be described with reference to FIG.

FIG. 1 is a block diagram showing a configuration of a light distribution control system 1 according to the present embodiment. As shown in FIG. 1, the light distribution control system 1 includes a control device 10, a clock unit 30, and a light distribution device 100.

The control device 10 acquires time information from the clock unit 30, and controls the light distribution device 100 based on the acquired time information. The light distribution device 100 is an optical device that controls the light distribution of the light incident on the light distribution device 100. Specifically, the light distribution device 100 can change the traveling direction of the light incident on the light distribution device 100 and emit it.

For example, the light distribution device 100 is applied to a window of a building or the like. The light distribution device 100 emits sunlight incident from diagonally above the outdoor side toward diagonally upward indoors. As a result, the light distribution device 100 can illuminate the ceiling surface and the like indoors with the sunlight taken in indoors, and can brighten the interior. Energy saving can be realized by using natural light such as sunlight.

As shown in FIG. 1, the control device 10 includes an acquisition unit 20 and a control unit 22.

The acquisition unit 20 includes a time acquisition unit 21. The time acquisition unit 21 acquires time information indicating the time. The time acquisition unit 21 is realized by an input interface or the like that receives the time information output by the clock unit 30. The time information indicates the time at the time of output by the clock unit 30 or the time of acquisition by the time acquisition unit 21, specifically, the current time. Time information is shown, for example, in units of hours, minutes, and seconds, but is not limited to this. The time information may further include a date.

The control unit 22 controls the light distribution device 100 based on the time information acquired by the time acquisition unit 21. Specifically, the control unit 22 determines whether or not the time indicated by the time information is included in the nighttime.

Nighttime is the period from sunset to sunrise. Specifically, nighttime is a predetermined fixed period. The nighttime is, for example, a period from 6:00 pm to 7:00 am the next morning, but is not limited to this.

Sunset and sunrise vary depending on the season and region. Therefore, the night may be a period that varies depending on the day, month, or season. For example, the control unit 22 may acquire the time of sunset and the time of sunrise for each day, and may determine the nighttime according to the acquired time. The nighttime may be determined based on the monthly average value, or may be determined based on the average value every several months (seasons). Further, at night, the value may be different for each region. The control unit 22 may acquire the latitude and longitude of the position where the light distribution device 100 is installed, and may acquire the time of sunset and the time of sunrise at the acquired latitude and longitude.

In the present embodiment, the control unit 22 has a plurality of drive modes. The plurality of drive modes include a lighting mode, a transparent mode and a security mode. The control unit 22 selects one from a plurality of drive modes based on the time information, and operates the light distribution device 100 in the selected drive mode. Details of the plurality of modes will be described later.

When the time indicated by the time information is included in the nighttime, the control unit 22 selects and executes the security mode as the drive mode of the light distribution device 100. When the time indicated by the time information is not included in the nighttime, the control unit 22 selects and executes the lighting mode or the transparent mode as the driving mode of the light distribution device 100. Which of the lighting mode and the transparent mode should be selected is predetermined by, for example, a user's instruction.

The control unit 22 controls the electric field applied to the light distribution layer 130 (see FIG. 2) of the light distribution device 100 based on the selected drive mode. Specifically, the control unit 22 controls the voltage applied between the first electrode layer 140 and the second electrode layer 150 of the light distribution device 100.

The control unit 22 is realized by a power supply circuit, a signal processing circuit, and the like. The power supply circuit receives electric power from, for example, a commercial power source, converts the received electric power into a predetermined voltage, and applies the electric power between the first electrode layer 140 and the second electrode layer 150. The signal processing circuit is realized, for example, by a non-volatile memory in which a program is stored, a volatile memory which is a temporary storage area for executing a program, an input / output port, a processor in which the program is executed, and the like.

The clock unit 30 is a timer for timing. For example, the clock unit 30 outputs time information indicating the current time to the control device 10.

[Light distribution device]
Hereinafter, the configuration of the light distribution device 100 will be described with reference to FIGS. 2 and 3. FIG. 2 is a cross-sectional view of the light distribution device 100 according to the present embodiment. FIG. 3 is an enlarged cross-sectional view of the light distribution device 100 according to the present embodiment, and is an enlarged cross-sectional view of the region III surrounded by the alternate long and short dash line in FIG.

As shown in FIGS. 2 and 3, the light distribution device 100 includes a first substrate 110, a second substrate 120, a light distribution layer 130, a first electrode layer 140, and a second electrode layer 150. The light distribution device 100 is configured to transmit incident light.

An adhesion layer for adhering the first electrode layer 140 and the uneven layer 131 of the light distribution layer 130 may be provided on the surface of the first electrode layer 140 on the light distribution layer 130 side. The adhesion layer is, for example, a translucent adhesive sheet, a resin material generally called a primer, or the like.

In the light distribution device 100, the first electrode layer 140, the light distribution layer 130, and the second electrode layer 150 are arranged between the paired first substrate 110 and the second substrate 120 in this order along the thickness direction. It is a composition. In order to maintain the distance between the first substrate 110 and the second substrate 120, a plurality of particulate spacers may be dispersed in the plane, or a columnar structure may be formed.

[First board and second board]
The first substrate 110 and the second substrate 120 are translucent base materials having translucency. As the first substrate 110 and the second substrate 120, for example, a glass substrate or a resin substrate can be used.

Examples of the material of the glass substrate include soda glass, non-alkali glass, and high refractive index glass. Examples of the material of the resin substrate include resin materials such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), acrylic (PMMA), and epoxy. The glass substrate has the advantages of high light transmittance and low moisture transmittance. On the other hand, the resin substrate has an advantage that it is less scattered at the time of destruction.

The first substrate 110 and the second substrate 120 may be made of the same material, or may be made of different materials. Further, the first substrate 110 and the second substrate 120 are not limited to the rigid substrate, and may be a flexible substrate having flexibility. In the present embodiment, the first substrate 110 and the second substrate 120 are transparent resin substrates made of PET resin.

The second substrate 120 is an opposing substrate facing the first substrate 110, and is arranged at a position facing the first substrate 110. The first substrate 110 and the second substrate 120 are arranged in parallel with a predetermined distance of, for example, 10 μm to 30 μm. The first substrate 110 and the second substrate 120 are adhered to each other by a sealing resin such as an adhesive formed in a frame shape on the outer periphery of each end.

The plan-view shape of the first substrate 110 and the second substrate 120 is, for example, a rectangular shape such as a square or a rectangle, but is not limited to this, and may be a polygon other than a circle or a quadrangle. Any shape can be adopted.

[Light distribution layer]
As shown in FIGS. 2 and 3, the light distribution layer 130 is arranged between the first electrode layer 140 and the second electrode layer 150. The light distribution layer 130 has a translucent property and transmits incident light. Further, the light distribution layer 130 distributes the incident light. That is, the light distribution layer 130 changes the traveling direction of the light when the light passes through the light distribution layer 130.

The light distribution layer 130 has an uneven layer 131 and a variable refractive index layer 132.

The uneven layer 131 is a fine-shaped layer provided to make the surface of the variable refractive index layer 132 uneven. As shown in FIG. 3, the uneven layer 131 has a plurality of convex portions 133 and a plurality of concave portions 134. Specifically, the concavo-convex layer 131 is a concavo-convex structure composed of a plurality of micro-order-sized convex portions 133. Between the plurality of convex portions 133, there are a plurality of concave portions 134. That is, one concave portion 134 is between the two adjacent convex portions 133.

The plurality of convex portions 133 are a plurality of convex portions arranged side by side in the z-axis direction parallel to the main surface of the first substrate 110 (specifically, the surface on which the first electrode layer 140 is provided). That is, in the present embodiment, the z-axis direction is the arrangement direction of the plurality of convex portions 133.

In the present embodiment, the plurality of convex portions 133 are long convex stripes extending in a direction orthogonal to the arrangement direction thereof. Specifically, the plurality of convex portions 133 are formed in a striped shape extending in the x-axis direction. Each of the plurality of convex portions 133 extends linearly along the x-axis direction. For example, each of the plurality of convex portions 133 is a triangular prism arranged sideways with respect to the first electrode layer 140. The plurality of convex portions 133 may extend while meandering along the x-axis direction. For example, the plurality of convex portions 133 may be formed in a wavy line stripe shape.

The plurality of convex portions 133 are arranged at equal intervals, for example, along the z-axis direction. The shapes and sizes of the plurality of convex portions 133 are the same as each other, but may be different from each other.

Each of the plurality of convex portions 133 has a shape that tapers from the root to the tip. Specifically, the cross-sectional shape of each of the plurality of convex portions 133 is a tapered shape that tapers along the direction from the first substrate 110 to the second substrate 120 (that is, the positive direction of the y-axis). Specifically, the cross-sectional shape of the convex portion 133 on the yz plane is triangular, but is not limited to this. The cross-sectional shape of the convex portion 133 may be a trapezoid, another polygon, or a polygon including a curve.

Specifically, as shown in FIG. 3, each of the plurality of convex portions 133 has a side surface 133a and a side surface 133b. Both the side surface 133a and the side surface 133b are in contact with the variable refractive index layer 132. That is, the side surface 133a and the side surface 133b are interfaces between the convex portion 133 and the variable refractive index layer 132.

The side surface 133a and the side surface 133b are surfaces that intersect in the z-axis direction, which is the arrangement direction of the convex portions 133. The side surface 133a and the side surface 133b are inclined surfaces that are inclined at a predetermined inclination angle with respect to the y-axis direction, which is the thickness direction, respectively. The distance between the side surface 133a and the side surface 133b gradually decreases toward the positive side of the y-axis.

In the present embodiment, the light distribution device 100 is installed in a window of a building or the like so that the z-axis is parallel to the vertical direction. For example, the light distribution device 100 is arranged so that the first substrate 110 is on the outdoor side and the second substrate 120 is on the indoor side.

The side surface 133a is, for example, a surface located vertically above the side surface 133b. The side surface 133a is a reflecting surface (total reflection surface) that reflects (specifically, total reflection) the incident light incident on the light distribution device 100. The side surface 133b is, for example, a surface located vertically below the side surface 133a. The side surface 133b is a refracting surface that refracts the incident light incident on the light distribution device 100.

The height (length in the y-axis direction) of each of the plurality of convex portions 133 is, for example, 2 μm to 100 μm, but is not limited to this. The width (length in the z-axis direction) of the plurality of convex portions 133 is, for example, 1 μm to 20 μm, preferably 10 μm or less, but is not limited to this. Further, the distance between the two adjacent convex portions 133 is, for example, 0 μm to 100 μm, but is not limited to this. The two adjacent convex portions 133 may be in contact with each other, or may be arranged at a predetermined interval.

As the material of the convex portion 133, a resin material having light transmittance such as acrylic resin, epoxy resin or silicone resin can be used. The convex portion 133 is formed from, for example, an ultraviolet curable resin material, and can be formed by molding, nanoimprinting, or the like.

The concavo-convex layer 131 can form, for example, an concavo-convex structure having a triangular cross section by mold embossing using an acrylic resin having a refractive index of 1.5. The height of the convex portions 133 is, for example, 10 μm, and the plurality of convex portions 133 are arranged at equal intervals of 2 μm in the z-axis direction. The width of the base of the convex portion 133 is, for example, 5 μm. The distance between the roots of the adjacent convex portions 133 can take a value of, for example, 0 μm to 5 μm.

The variable refractive index layer 132 is arranged so as to fill the space between the plurality of convex portions 133 (that is, the concave portion 134) of the concave-convex layer 131. The variable refractive index layer 132 is arranged so as to fill the gap formed between the first electrode layer 140 and the second electrode layer 150. For example, as shown in FIG. 3, since the convex portion 133 and the second electrode layer 150 are separated from each other, the refractive index variable layer 132 fills the gap between the convex portion 133 and the second electrode layer 150. Be placed. The convex portion 133 and the second electrode layer 150 may be in contact with each other. In this case, the variable refractive index layer 132 may be provided separately for each concave portion 134.

The refractive index of the variable refractive index layer 132 changes according to the applied electric field. The electric field changes according to the voltage applied between the first electrode layer 140 and the second electrode layer 150. Specifically, the variable refractive index layer 132 functions as a refractive index adjusting layer in which the refractive index in the visible light region can be adjusted by applying an electric field.

For example, the variable refractive index layer 132 is composed of a liquid crystal having liquid crystal molecules 135 having electric field responsiveness. When an electric field is applied to the light distribution layer 130, the orientation state of the liquid crystal molecules 135 changes and the refractive index of the refractive index variable layer 132 changes.

The birefringent material of the variable refractive index layer 132 is, for example, a liquid crystal containing liquid crystal molecules 135 having birefringence. As such a liquid crystal, for example, a nematic liquid crystal in which the liquid crystal molecule 135 is a rod-shaped molecule, a smectic liquid crystal, a cholesteric liquid crystal, or the like can be used. For example, when the refractive index of the convex portion 133 is 1.5, the material of the variable refractive index layer 132 has an ordinary light refractive index (no) of 1.5 and an abnormal light refractive index (ne) of 1.7. A positive type liquid crystal can be used.

The variable refractive index layer 132 seals the outer periphery of each end of, for example, the first substrate 110 on which the first electrode layer 140 and the uneven layer 131 are formed, and the second substrate 120 on which the second electrode layer 150 is formed. It is formed by injecting a liquid crystal material by a vacuum injection method in a state of being sealed with a resin. Alternatively, the variable refractive index layer 132 is formed by dropping the liquid crystal material onto the first electrode layer 140 and the uneven layer 131 of the first substrate 110 and then laminating the second substrate 120.

Note that FIG. 3 shows a state in which no voltage is applied and no electric field is applied. In this case, the liquid crystal molecules 135 are oriented so that the major axis is substantially parallel to the x-axis. When a voltage is applied between the first electrode layer 140 and the second electrode layer 150, the liquid crystal molecules 135 are oriented so that the major axis is substantially parallel to the y axis (see FIG. 4B described later). ..

Further, an electric field may be applied to the variable refractive index layer 132 by AC power, or an electric field may be applied by DC power. In the case of AC power, the voltage waveform may be a sine wave or a square wave.

[1st electrode layer and 2nd electrode layer]
The first electrode layer 140 and the second electrode layer 150 are electrically paired and are configured to be able to apply an electric field to the light distribution layer 130. The first electrode layer 140 and the second electrode layer 150 are paired not only electrically but also in terms of arrangement, and are arranged between the first substrate 110 and the second substrate 120 so as to face each other. ing. Specifically, the first electrode layer 140 and the second electrode layer 150 are arranged so as to sandwich the light distribution layer 130.

The first electrode layer 140 and the second electrode layer 150 have translucency and transmit incident light. The first electrode layer 140 and the second electrode layer 150 are, for example, transparent conductive layers. The material of the transparent conductive layer is a conductor-containing resin made of a transparent metal oxide such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide), a resin containing a conductor such as silver nanowires or conductive particles, or a conductor-containing resin. , A metal thin film such as a silver thin film can be used. The first electrode layer 140 and the second electrode layer 150 may have a single layer structure thereof, or may have a laminated structure thereof (for example, a laminated structure of a transparent metal oxide and a metal thin film). In the present embodiment, the first electrode layer 140 and the second electrode layer 150 are each ITO having a thickness of 100 nm.

The first electrode layer 140 is arranged between the first substrate 110 and the uneven layer 131. Specifically, the first electrode layer 140 is formed on the surface of the first substrate 110 on the light distribution layer 130 side.

On the other hand, the second electrode layer 150 is arranged between the variable refractive index layer 132 and the second substrate 120. Specifically, the second electrode layer 150 is formed on the surface of the second substrate 120 on the light distribution layer 130 side.

The first electrode layer 140 and the second electrode layer 150 are configured so as to enable electrical connection with, for example, the control device 10. For example, an electrode pad or the like for connecting to the control device 10 may be drawn out from each of the first electrode layer 140 and the second electrode layer 150 and formed on the first substrate 110 and the second substrate 120.

The first electrode layer 140 and the second electrode layer 150 are formed by, for example, vapor deposition, sputtering, or the like, respectively. The first electrode layer 140 and the second electrode layer 150 are each formed by forming a transparent conductive film such as ITO.

[Drive mode]
Subsequently, the details of the three drive modes executed by the control device 10 will be described.

<Daylighting mode>
First, the lighting mode will be described with reference to FIG. 4A. FIG. 4A is an enlarged cross-sectional view for explaining the lighting mode of the light distribution device 100 according to the present embodiment.

The daylighting mode is a daylighting mode in which the traveling direction of the light incident on the light distribution device 100 is bent and emitted in a direction different from the incident direction. The daylighting mode is specifically executed in the daytime if the current time is not included in the nighttime. The lighting mode is a first mode in which a first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 132.

When the light distribution device 100 is operated in the lighting mode, the control unit 22 applies a predetermined first voltage between the first electrode layer 140 and the second electrode layer 150. Specifically, the control unit 22 applies an in-plane uniform first voltage between the first electrode layer 140 and the second electrode layer 150. As a result, the electric field applied to the variable refractive index layer 132 becomes substantially uniform in the plane, and the refractive index of the variable refractive index layer 132 can be made substantially uniform in the plane.

The magnitude of the first voltage applied in the daylighting mode is determined, for example, based on the incident angle of sunlight. The angle of incidence of sunlight changes throughout the day due to the diurnal motion of the sun. Therefore, for example, the control unit 22 adjusts the magnitude of the first voltage applied based on the solar altitude within a predetermined range. The larger the magnitude of the first voltage, the closer the light distribution device 100 is to the state of being driven in the transparent mode. The smaller the magnitude of the first voltage, the closer the light distribution device 100 is to the state of being driven in the security mode. The refractive index of the variable refractive index layer 132 changes in the range of 1.5 to 1.7 depending on the orientation state of the liquid crystal molecules 135.

For example, in FIG. 4A, the liquid crystal molecule 135 shows a state in which its major axis direction is obliquely oriented in the xy plane. At this time, the S polarization component of the light L incident from the outdoor side receives the refractive index of the liquid crystal molecule 135 in the oblique direction. The refractive index of the variable refractive index layer 132 at this time is, for example, 1.6.

Due to the difference in refractive index at the interface between the convex portion 133 and the variable refractive index layer 132, as shown in FIG. 4A, the light L incident from the outdoor side is refracted by the side surface 133b and then reflected by the side surface 133a (total). (Reflected). As a result, the light L such as sunlight incident obliquely downward is bent in the traveling direction by the light distribution device 100 and is irradiated to the ceiling surface or the like indoors. The direction of the light L emitted from the light distribution device 100 changes depending on the difference in the refractive index at the interface between the convex portion 133 and the variable refractive index layer 132. Therefore, the control unit 22 adjusts the electric field applied to the variable refractive index layer 132, that is, the magnitude of the first voltage applied to the first electrode layer 140 and the second electrode layer 150 from the light distribution device 100. The direction of the emitted light L can be changed.

Since the P-polarized light component of the light L receives the refractive index of the liquid crystal molecule 135 in the minor axis direction, it passes through the light distribution device 100 as it is. That is, the P-polarized light component of the light L is not bent in the traveling direction and is not distributed.

Further, the light L actually enters the first substrate 110, exits from the second substrate 120, passes through the interface between the first substrate 110 and the first electrode layer 140, and the second It is refracted when it passes through the interface between the electrode layer 150 and the second substrate 120, and when the passing medium changes, but it is not shown in FIG. 4A. In FIG. 4A, only refraction and reflection (total reflection) at the interface between the convex portion 133 and the variable refractive index layer 132 are shown. The same applies to FIGS. 4B and 4C, which will be described later, and FIGS. 14A to 14C.

<Transparent mode>
Next, the transparent mode will be described with reference to FIG. 4B. FIG. 4B is an enlarged cross-sectional view for explaining the transparent mode of the light distribution device 100 according to the present embodiment.

The transparent mode is a mode in which the light incident on the light distribution device 100 is transmitted as it is. The transparent mode is an example of a third mode in which the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132 is substantially zero. The transparent mode is specifically executed during the day if the current time is not included at night.

When the light distribution device 100 is operated in the transparent mode, the control unit 22 applies a predetermined second voltage between the first electrode layer 140 and the second electrode layer 150. Specifically, the control unit 22 applies an in-plane uniform second voltage between the first electrode layer 140 and the second electrode layer 150. As a result, the electric field applied to the variable refractive index layer 132 becomes substantially uniform in the plane, and the refractive index of the variable refractive index layer 132 can be made substantially uniform in the plane.

The magnitude of the second voltage applied in the transparent mode is such that a plurality of liquid crystal molecules 135 contained in the variable refractive index layer 132 can be sufficiently oriented. Specifically, when the transparent mode is executed, the control unit 22 applies a voltage having a value larger than the voltage applied in either the lighting mode or the security mode.

In this case, as shown in FIG. 4B, the liquid crystal molecule 135 is oriented so that its major axis direction is along the thickness direction (y-axis direction) of the light distribution device 100. Therefore, the light L incident from the outdoor side receives the refractive index of the liquid crystal molecule 135 in the minor axis direction. In the transparent mode, both the P-polarizing component and the S-polarizing component of the light L receive the refractive index of the liquid crystal molecule 135 in the minor axis direction.

The refractive index in the minor axis direction is the normal light refractive index (no), which is equal to the refractive index of 1.5 of the convex portion 133. Therefore, the difference in refractive index at the interface between the convex portion 133 and the variable refractive index layer 132 becomes substantially zero.

Therefore, as shown in FIG. 4B, the light L such as sunlight incident obliquely downward passes through the light distribution device 100 as it is and irradiates the indoor floor or the like.

<Security mode>
Next, the security mode will be described with reference to FIG. 4C. FIG. 4C is an enlarged cross-sectional view for explaining the security mode of the light distribution device 100 according to the present embodiment.

The security mode is a mode in which the light passing through the light distribution device 100 from the second substrate 120 to the first substrate 110 is scattered. The security mode is an example of a second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 132. That is, in the security mode, a refractive index difference larger than the refractive index difference generated in the lighting mode is generated. Security mode is executed when the current time is included at night.

The second refractive index difference is, for example, the maximum value of the refractive index difference that can occur at the interface between the plurality of convex portions 133 and the refractive index variable layer 132. The second refractive index difference does not have to be the maximum value, but the larger the value, the higher the light scattering effect.

In the security mode, the control unit 22 does not apply a voltage between the first electrode layer 140 and the second electrode layer 150. That is, no electric field is applied to the variable refractive index layer 132.

In this case, as shown in FIG. 4C, the liquid crystal molecules 135 are oriented in the major axis direction along the alignment direction of the convex portions 133. Therefore, the S polarization component of the light L incident from the indoor side receives the refractive index in the long axis direction of the liquid crystal molecule 135. The refractive index in the major axis direction is an abnormal light refractive index (ne), specifically 1.7. Therefore, the difference between the refractive index 1.7 of the variable refractive index layer 132 and the refractive index 1.5 of the convex portion 133 becomes the maximum value at 0.2.

Therefore, as shown in FIG. 4C, the light L incident on the second substrate 120 in the horizontal direction from the indoor side is reflected (totally reflected) by the side surfaces 133a and 133b of the convex portion 133 and scattered in various directions. ..

Since the P-polarized light component of the light L receives the refractive index of the liquid crystal molecule 135 in the minor axis direction, it passes through the light distribution device 100 as it is, as in the transparent mode.

As described above, when an attempt is made to look indoors from the outdoor side via the light distribution device 100, the S polarization component of the light L from the indoors is scattered in the security mode. Therefore, the light distribution device 100 functions like frosted glass, and the indoor state can be obscured from the outside. The larger the difference in refractive index between the convex portion 133 and the variable refractive index layer 132, the higher the scattering effect, and therefore the higher the security effect.

[motion]
Subsequently, the operation of the control device 10 of the light distribution control system 1 according to the present embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing a control method of the light distribution device 100 according to the present embodiment.

As shown in FIG. 5, first, the time acquisition unit 21 acquires time information from the clock unit 30 (S10). The time information specifically indicates the current time.

Next, the control unit 22 determines whether or not the current time is included in the nighttime (S11). When the current time is included in the nighttime (Yes in S11), the control unit 22 executes the security mode (S12). Specifically, the control unit 22 maximizes the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132.

When the current time is not included in the nighttime (No in S11), the control unit 22 executes the lighting mode or the transparent mode (S13). For example, the control unit 22 executes the lighting mode when there is no instruction from the user. The control unit 22 may switch from the lighting mode to the transparent mode when receiving an instruction from the user.

When the control unit 22 does not end the control of the light distribution device 100 (No in S14), the control unit 22 returns to step S11 and repeats the above-described processing. When the control of the light distribution device 100 is terminated by an instruction from a user or the like (Yes in S14), the control unit 22 terminates the control of the light distribution device 100. At the end, for example, the drive mode being executed in step S12 or step S13 is maintained. Alternatively, the control unit 22 may operate the light distribution device 100 in a predetermined drive mode, or may stop the electric field applied to the light distribution layer 130.

[Effects, etc.]
As described above, the light distribution control system 1 according to the present embodiment includes the control device 10 of the light distribution device 100 and the light distribution device 100. The control device 10 of the light distribution device 100 according to the present embodiment includes a light distribution layer 20 that acquires time information indicating a time and a light distribution layer 130 that distributes incident light based on the time information. It includes a control unit 22 that controls the device 100. The light distribution layer 130 includes a concavo-convex layer 131 having a plurality of convex portions 133 and a refractive index variable layer 132 arranged so as to fill the space between the plurality of convex portions 133 and whose refractive index changes according to an applied electric field. Be prepared. The control unit 22 includes a light collection mode, which is an example of a first mode in which a first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 132, and the plurality of convex portions 133 and the variable refractive index layer 132. It has a security mode which is an example of a second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface with. The control unit 22 executes the security mode when the time indicated by the time information is included in the nighttime.

As a result, in the security mode, the difference in refractive index becomes larger than in the lighting mode, so that the light scattering effect can be enhanced. When it is brighter indoors than outdoors, such as at night, the light distribution device 100 can scatter light from indoors. Therefore, when the inside is viewed from the outside through the light distribution device 100, the light from the inside is scattered, which makes it difficult to see the inside. As described above, according to the present embodiment, security can be enhanced.

Further, for example, the second refractive index difference is the maximum value of the refractive index difference that can occur at the interface between the plurality of convex portions 133 and the refractive index variable layer 132.

As a result, the scattering effect of the light distribution device 100 can be maximized, so that the security can be sufficiently enhanced.

Further, for example, the control unit 22 further has a transparent mode which is an example of a third mode in which the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132 is substantially zero.

As a result, the light distribution device 100 can function as a window.

Further, for example, the light distribution control method according to the present embodiment is a light distribution device including an acquisition step of acquiring time information indicating a time and a light distribution layer 130 that distributes incident light based on the time information. Includes a control step to control 100. In the control step, a light collection mode in which a first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 132, and a first refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132. A security mode that generates a second refractive index difference larger than the difference is selectively executed. If the time indicated by the time information is included at night, the security mode is executed. Further, for example, the program according to the present embodiment is a program for causing a computer to execute the above light distribution control method.

As a result, security can be enhanced as in the control device 10.

(Embodiment 2)
Subsequently, the light distribution control system according to the second embodiment will be described.

[Constitution]
FIG. 6 is a block diagram showing a configuration of the light distribution control system 2 according to the present embodiment. As shown in FIG. 6, the light distribution control system 2 is newly provided with the control device 10a instead of the control device 10 as compared with the light distribution control system 1 according to the first embodiment shown in FIG. The difference is that the outdoor illuminance meter 31 is provided. In the following, the differences from the first embodiment will be mainly described, and the common points will be omitted or simplified.

The control device 10a controls the light distribution device 100 based not only on the time information but also on the outdoor illuminance detected by the outdoor illuminance meter 31. As shown in FIG. 6, the control device 10a includes an acquisition unit 20a and a control unit 22a.

The acquisition unit 20a includes a time acquisition unit 21 and an outdoor illuminance acquisition unit 21a. The time acquisition unit 21 is the same as that of the first embodiment.

The outdoor illuminance acquisition unit 21a acquires outdoor illuminance information indicating outdoor illuminance. The outdoor illuminance acquisition unit 21a is realized by an input interface or the like that receives the outdoor illuminance information output by the outdoor illuminance meter 31. The outdoor illuminance information indicates, for example, the outdoor illuminance at the position where the light distribution device 100 is installed.

In addition to the operation of the control unit 22, the control unit 22a executes the security mode when the illuminance indicated by the outdoor illuminance information is equal to or less than a predetermined threshold value. For example, the control unit 22a compares the illuminance indicated by the outdoor illuminance information with the threshold value when the current time is not included in the nighttime. When the illuminance indicated by the outdoor illuminance information is equal to or less than the threshold value, specifically when the outdoors are dark, the control unit 22a executes the security mode. The threshold value here is, for example, 1000 Lux.

The outdoor illuminometer 31 is an illuminometer arranged on the outdoor side of the light distribution device 100. For example, the outdoor illuminance meter 31 may be attached to the outdoor side surface of the first substrate 110 of the light distribution device 100. The outdoor illuminance meter 31 detects the illuminance of light incident on the light distribution device 100 from the outside such as sunlight, and outputs outdoor illuminance information indicating the detected illuminance.

[motion]
Subsequently, the operation of the control device 10a of the light distribution control system 2 according to the present embodiment will be described with reference to FIG. 7. FIG. 7 is a flowchart showing a control method of the light distribution device 100 according to the present embodiment.

As shown in FIG. 7, first, the time acquisition unit 21 acquires time information from the clock unit 30 (S10). The time information specifically indicates the current time.

Next, the control unit 22a determines whether or not the current time is included in the nighttime (S11). When the current time is included in the nighttime (Yes in S11), the control unit 22a executes the security mode (S12). Specifically, the control unit 22a maximizes the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132.

When the current time is not included at night (No in S11), the outdoor illuminance acquisition unit 21a acquires outdoor illuminance information from the outdoor illuminance meter 31 (S20). Next, the control unit 22a compares the outdoor illuminance indicated by the outdoor illuminance information with a predetermined threshold value (S21).

When the outdoor illuminance is below the threshold value, that is, when the outdoors are dark (Yes in S21), the control unit 22a executes the security mode (S12). When the outdoor illuminance is larger than the threshold value, that is, when the outdoors are bright (No in S21), the control unit 22a executes the lighting mode or the transparent mode (S13). For example, the control unit 22a executes the lighting mode when there is no instruction from the user. The control unit 22a may switch from the lighting mode to the transparent mode when receiving an instruction from the user.

When the control unit 22a does not end the control of the light distribution device 100 (No in S14), the control unit 22a returns to step S11 and repeats the above-described processing. When the control of the light distribution device 100 is terminated by an instruction from a user or the like (Yes in S14), the control unit 22a ends the control of the light distribution device 100.

[Effects, etc.]
As described above, in the control device 10a of the light distribution device 100 according to the present embodiment, the acquisition unit 20a further acquires the outdoor illuminance information indicating the outdoor illuminance. The control unit 22a executes the security mode when the illuminance indicated by the outdoor illuminance information is equal to or less than a predetermined threshold value.

For example, even in the daytime, when the weather is cloudy or rainy and the outdoors are dark, if the indoors are bright, it becomes easier to see the indoor situation from the outdoors. According to this embodiment, the security mode can be executed when the outdoors are dark even if the current time is not included at night. Therefore, according to the present embodiment, the security of the light distribution device 100 can be further enhanced.

Further, regardless of the season or region, even when the nighttime setting is set to a fixed value, the security mode can be executed when the outdoors become dark. Therefore, for example, when the sunset is early such as in winter, the security mode can be executed even when the current time is not included in the nighttime. As described above, according to the present embodiment, the security of the light distribution device 100 can be further enhanced.

(Embodiment 3)
Subsequently, the light distribution control system according to the third embodiment will be described.

[Constitution]
FIG. 8 is a block diagram showing a configuration of the light distribution control system 3 according to the present embodiment. As shown in FIG. 8, the light distribution control system 3 is newly provided with the control device 10b instead of the control device 10a as compared with the light distribution control system 2 according to the second embodiment shown in FIG. The difference is that the indoor illuminance meter 32 is provided. In the following, the differences from the second embodiment will be mainly described, and the common points will be omitted or simplified.

The control device 10b controls the light distribution device 100 based not only on the time information but also on the outdoor and indoor illuminance detected by the outdoor illuminance meter 31 and the indoor illuminance meter 32. As shown in FIG. 8, the control device 10b includes an acquisition unit 20b and a control unit 22b.

The acquisition unit 20b includes a time acquisition unit 21, an outdoor illuminance acquisition unit 21a, and an indoor illuminance acquisition unit 21b. The time acquisition unit 21 is the same as that of the first embodiment. The outdoor illuminance acquisition unit 21a is the same as that of the second embodiment.

The indoor illuminance acquisition unit 21b acquires indoor illuminance information indicating indoor illuminance. The indoor illuminance acquisition unit 21b is realized by an input interface or the like that receives indoor illuminance information output by the indoor illuminance meter 32. The indoor illuminance information indicates, for example, the indoor illuminance of the building in which the light distribution device 100 is installed.

In addition to the operation of the control unit 22, the control unit 22b executes the security mode when the illuminance indicated by the indoor illuminance information is larger than the illuminance indicated by the outdoor illuminance information. For example, the control unit 22b compares the illuminance indicated by the indoor illuminance information with the illuminance indicated by the outdoor illuminance information when the current time is not included in the nighttime. The control unit 22b executes the security mode when the illuminance indicated by the indoor illuminance information is larger than the illuminance indicated by the outdoor illuminance information, specifically, when the indoor is brighter than the outdoor.

The indoor illuminometer 32 is an illuminometer arranged on the indoor side of the light distribution device 100. For example, the indoor illuminance meter 32 may be attached to the indoor side surface of the second substrate 120 of the light distribution device 100. The indoor illuminance meter 32 detects the illuminance of light emitted from a lighting device or the like arranged indoors and incident on the light distribution device 100, and outputs indoor illuminance information indicating the detected illuminance.

In the present embodiment, as in the second embodiment, the control unit 22b may execute the security mode when the outdoor illuminance is equal to or higher than the threshold value. That is, it may be determined whether or not to execute the security mode by using only the outdoor illuminance as well as the illuminance difference between the outdoor and the indoor.

[motion]
Subsequently, the operation of the control device 10b of the light distribution control system 3 according to the present embodiment will be described with reference to FIG. FIG. 9 is a flowchart showing a control method of the light distribution device 100 according to the present embodiment.

As shown in FIG. 9, first, the time acquisition unit 21 acquires time information from the clock unit 30 (S10). The time information specifically indicates the current time.

Next, the control unit 22b determines whether or not the current time is included in the nighttime (S11). When the current time is included in the nighttime (Yes in S11), the control unit 22b executes the security mode (S12). Specifically, the control unit 22b maximizes the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132.

When the current time is not included in the nighttime (No in S11), the indoor illuminance acquisition unit 21b acquires the indoor illuminance information from the indoor illuminance meter 32, and the outdoor illuminance acquisition unit 21a acquires the outdoor illuminance information from the outdoor illuminance meter 31. (S30). Next, the control unit 22b compares the indoor illuminance indicated by the indoor illuminance information with the outdoor illuminance indicated by the outdoor illuminance information (S31).

When the indoor illuminance is larger than the outdoor illuminance, that is, when the indoor illuminance is bright (Yes in S31), the control unit 22b executes the security mode (S12). When the indoor illuminance is equal to or less than the outdoor illuminance, that is, when the indoor illuminance is dark (No in S31), the control unit 22b executes the lighting mode or the transparent mode (S13). For example, the control unit 22b executes the lighting mode when there is no instruction from the user. The control unit 22b may switch from the lighting mode to the transparent mode when receiving an instruction from the user.

When the control unit 22b does not end the control of the light distribution device 100 (No in S14), the control unit 22b returns to step S11 and repeats the above-described processing. When the control of the light distribution device 100 is terminated by an instruction from a user or the like (Yes in S14), the control unit 22b ends the control of the light distribution device 100.

[Effects, etc.]
As described above, in the control device 10b of the light distribution device 100 according to the present embodiment, the acquisition unit 20b further acquires the outdoor illuminance information indicating the outdoor illuminance and the indoor illuminance information indicating the indoor illuminance. .. The control unit 22b executes the security mode when the illuminance indicated by the indoor illuminance information is larger than the illuminance indicated by the outdoor illuminance information.

For example, even in the daytime, when the weather is cloudy or rainy and the indoors are brighter than the outdoors, it becomes easier to see the indoors from the outdoors. According to this embodiment, the security mode can be executed when the indoor area is brighter than the outdoor area even if the current time is not included in the nighttime. Therefore, according to the present embodiment, the security of the light distribution device 100 can be further enhanced.

Further, regardless of the season or region, even when the nighttime setting is set to a fixed value, the security mode can be executed when the indoor area becomes brighter than the outdoor area. Therefore, for example, when the sunset is early such as in winter, the security mode can be executed even when the current time is not included in the nighttime. As described above, according to the present embodiment, the security of the light distribution device 100 can be further enhanced.

(Embodiment 4)
Subsequently, the light distribution control system according to the fourth embodiment will be described.

[Constitution]
FIG. 10 is a block diagram showing the configuration of the light distribution control system 4 according to the present embodiment. As shown in FIG. 10, the light distribution control system 4 is newly provided with the control device 10c instead of the control device 10 as compared with the light distribution control system 1 according to the first embodiment shown in FIG. The difference is that the terminal device 33 is provided. In the following, the differences from the first embodiment will be mainly described, and the common points will be omitted or simplified.

The control device 10c controls the light distribution device 100 based on not only the time information but also the operation information transmitted from the terminal device 33. As shown in FIG. 10, the control device 10c includes an acquisition unit 20c and a control unit 22c.

The acquisition unit 20c includes a time acquisition unit 21 and a reception unit 21c. The time acquisition unit 21 is the same as that of the first embodiment.

The receiving unit 21c acquires operation information from the terminal device 33. The receiving unit 21c is realized by a communication interface or an infrared receiver that receives the operation information output by the terminal device 33.

The operation information is information for selecting the drive mode of the light distribution device 100. Specifically, the operation information includes mode information for selecting a security mode. The operation information may include mode information for selecting each of the lighting mode and the transparent mode.

In addition to the operation of the control unit 22, the control unit 22c executes the security mode when the acquisition unit 20c acquires the operation information. Specifically, the control unit 22c executes the drive mode indicated by the mode information included in the operation information received by the reception unit 21c. For example, the control unit 22c executes the security mode when the receiving unit 21c receives the mode information indicating the security mode when the current time is not included in the nighttime.

Further, for example, the control unit 22c executes the lighting mode when the receiving unit 21c receives the mode information indicating the lighting mode. Similarly, the control unit 22c executes the transparent mode when the receiving unit 21c receives the mode information indicating the transparent mode.

The terminal device 33 is an operation terminal for instructing the drive mode of the light distribution device 100. The terminal device 33 is, for example, an information processing terminal such as a smartphone, but may be a dedicated remote controller. The user can instruct the drive mode of the light distribution device 100 by operating the terminal device 33. The terminal device 33 transmits mode information indicating the drive mode instructed by the user to the control device 10c.

As a result, the user can operate the light distribution device 100 in an arbitrary drive mode at an arbitrary timing by operating the terminal device 33. For example, the light distribution device 100 can be operated in the security mode in the daytime. The user can also instruct the switching between the lighting mode and the transparent mode of the light distribution device 100. In addition, the light distribution device 100 can be operated in the transparent mode or the daylighting mode at night.

In the present embodiment, as in the second embodiment, the acquisition unit 20c may include the outdoor illuminance acquisition unit 21a. The control unit 22c may further execute the security mode when the outdoor illuminance is equal to or higher than the threshold value. That is, it may be determined whether or not to execute the security mode by using not only the operation information but also the outdoor illuminance.

Further, as in the third embodiment, the acquisition unit 20c may include an outdoor illuminance acquisition unit 21a and an indoor illuminance acquisition unit 21b. The control unit 22c may further execute the security mode when the indoor illuminance is larger than the outdoor illuminance. That is, it may be determined whether or not to execute the security mode by using not only the operation information but also the difference in illuminance between the outdoors and the operation.

As described above, the control unit 22c may execute the security mode when at least one of the plurality of conditions is satisfied. The plurality of conditions include (i) the current time is included at night, (ii) the outdoor illuminance is equal to or higher than the threshold value, (iii) the indoor illuminance is larger than the outdoor illuminance, and (iv). It includes the acquisition of operation information from the terminal device. For example, the control unit 22c executes the security mode when at least one of the conditions (i) to (iv) is satisfied.

[motion]
Subsequently, the operation of the control device 10c of the light distribution control system 4 according to the present embodiment will be described with reference to FIG. FIG. 11 is a flowchart showing a control method of the light distribution device 100 according to the present embodiment.

As shown in FIG. 11, first, the time acquisition unit 21 acquires time information from the clock unit 30 (S10). The time information specifically indicates the current time.

Next, the control unit 22c determines whether or not the current time is included in the nighttime (S11). When the current time is included in the nighttime (Yes in S11), the control unit 22c executes the security mode (S12). Specifically, the control unit 22c maximizes the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 132.

When the current time is not included in the nighttime (No in S11), when the receiving unit 21c acquires the operation information (Yes in S40), the control unit 22c executes the security mode (S12). Specifically, when the receiving unit 21c acquires the mode information indicating the security mode, the control unit 22c executes the security mode.

When the receiving unit 21c does not acquire the operation information (No in S40), the control unit 22c executes the lighting mode or the transparent mode (S13). For example, the control unit 22c executes the lighting mode when there is no instruction from the user. The control unit 22c may switch from the lighting mode to the transparent mode when receiving an instruction from the user.

When the control unit 22c does not end the control of the light distribution device 100 (No in S14), the control unit 22c returns to step S11 and repeats the above-described processing. When the control of the light distribution device 100 is terminated by an instruction from a user or the like (Yes in S14), the control unit 22c ends the control of the light distribution device 100.

Although not shown in FIG. 11, even when the current time is included at night, when the receiving unit 21c receives the mode information indicating the transparent mode or the lighting mode, the control unit 22c receives the mode. The drive mode indicated by the information may be executed.

[Effects, etc.]
As described above, in the control device 10c of the light distribution device 100 according to the present embodiment, the acquisition unit 20c further acquires the operation information for selecting the security mode from the terminal device 33. The control unit 22c executes the security mode when the acquisition unit 20c acquires the operation information.

As a result, the security mode can be executed at an arbitrary timing by operating the terminal device 33. Since the security mode can be executed when the user requests it regardless of the surrounding environment, the security of the light distribution device 100 can be further enhanced.

(Embodiment 5)
Subsequently, the light distribution control system according to the fifth embodiment will be described.

The light distribution control system according to the present embodiment includes a light distribution device different from the light distribution device 100 included in each of the light distribution control systems 1 to 4 according to the first to fourth embodiments. The operation of the control device that controls the light distribution device according to the present embodiment is the same as the operation described in the first to fourth embodiments. In the following, the configuration of the light distribution device according to this embodiment will be mainly described, and the description of common points with other embodiments will be omitted or simplified.

FIG. 12 is a cross-sectional view of the light distribution device 200 according to the present embodiment. FIG. 13 is an enlarged cross-sectional view of the light distribution device 200 according to the present embodiment, and is an enlarged cross-sectional view of the region XIII surrounded by the alternate long and short dash line in FIG.

As shown in FIGS. 12 and 13, the light distribution device 200 includes a first substrate 110, a second substrate 120, a light distribution layer 230, a first electrode layer 140, and a second electrode layer 150. The configuration other than the light distribution layer 230 is the same as that of the first embodiment.

The light distribution layer 230 is arranged between the first electrode layer 140 and the second electrode layer 150. The light distribution layer 230 has a translucent property and transmits incident light. Further, the light distribution layer 230 changes the traveling direction of the light when the light passes through the light distribution layer 230.

The light distribution layer 230 has an uneven layer 131 and a variable refractive index layer 232. The uneven layer 131 has the same configuration as the uneven layer 131 of the light distribution device 100.

As shown in FIG. 13, the variable refractive index layer 232 has an insulating liquid 235 and nanoparticles 236 contained in the insulating liquid 235. The variable refractive index layer 232 is a nanoparticle dispersion layer in which innumerable nanoparticles 236 are dispersed in an insulating liquid 235.

The insulating liquid 235 is a transparent liquid having an insulating property, and is a solvent that serves as a dispersion medium in which nanoparticles 236 are dispersed as a dispersoid. As the insulating liquid 235, for example, a material having a refractive index (solvent refractive index) of about 1.3 to about 1.5 can be used. In this embodiment, an insulating liquid 235 having a refractive index of about 1.4 is used.

The kinematic viscosity of the insulating liquid 235 is preferably about 100 mm ² / s. Further, the insulating liquid 235 has a low dielectric constant (for example, the dielectric constant of the uneven layer 131 or less), is non-flammable (for example, a high flash point having a flash point of 250 ° C. or higher), and has low volatility. Good. Specifically, the insulating liquid 235 is a hydrocarbon such as an aliphatic hydrocarbon, naphtha, and other petroleum-based solvents, a low molecular weight halogen-containing polymer, or a mixture thereof. As an example, the insulating liquid 235 is a halogenated carbon hydrogen such as fluorocarbon hydrogen. As the insulating liquid 235, silicone oil or the like can also be used.

A plurality of nanoparticles 236 are dispersed in the insulating liquid 235. The nanoparticles 236 are fine particles having a particle size of nanoorder size. Specifically, assuming that the wavelength of the incident light is λ, the particle size of the nanoparticles 236 is preferably λ / 4 or less. By making the particle size of the nanoparticles 236 λ / 4 or less, it is possible to reduce light scattering by the nanoparticles 236 and obtain an average refractive index between the nanoparticles 236 and the insulating liquid 235. The smaller the particle size of the nanoparticles 236, the better, preferably 100 nm or less, and more preferably several nm to several tens of nm.

The nanoparticles 236 are made of, for example, a high refractive index material. Specifically, the refractive index of the nanoparticles 236 is higher than that of the insulating liquid 235. In the present embodiment, the refractive index of the nanoparticles 236 is higher than the refractive index of the uneven layer 131.

As the nanoparticles 236, metal oxide fine particles can be used. Further, the nanoparticles 236 may be made of a material having a high transmittance. In the present embodiment, transparent zirconia particles having a refractive index of 2.1 and composed of zirconium oxide (ZrO ₂ ) are used as nanoparticles 236. The nanoparticles 236 are not limited to zirconium oxide, and may be made of titanium oxide or the like.

Further, the nanoparticles 236 are charged particles that are charged. For example, by modifying the surface of the nanoparticles 236, the nanoparticles 236 can be positively (plus) or negatively (minus) charged. In this embodiment, the nanoparticles 236 are positively charged.

In the variable refractive index layer 232 configured in this way, the charged nanoparticles 236 are dispersed throughout the insulating liquid 235. In the present embodiment, zirconia particles having a refractive index of 2.1 are used as nanoparticles 236, and nanoparticles 236 dispersed in an insulating liquid 235 having a refractive index of about 1.4 are used as a variable refractive index layer. It is set to 232.

Further, the overall refractive index (average refractive index) of the variable refractive index layer 232 is set to be substantially the same as the refractive index of the concave-convex layer 131 in a state where the nanoparticles 236 are uniformly dispersed in the insulating liquid 235. In the present embodiment, it is about 1.5. The overall refractive index of the variable refractive index layer 232 can be changed by adjusting the concentration (amount) of the nanoparticles 236 dispersed in the insulating liquid 235. Although the details will be described later, the amount of nanoparticles 236 is, for example, such that the nanoparticles 134 are buried in the recesses 134 of the uneven layer 131. In this case, the concentration of nanoparticles 236 with respect to the insulating liquid 235 is about 10% to 30%.

The variable refractive index layer 232 is arranged between the uneven layer 131 and the second electrode layer 150. Specifically, the variable refractive index layer 232 is in contact with the uneven layer 131. That is, the contact surface of the variable refractive index layer 232 with the uneven surface of the uneven layer 131 is the interface between the variable refractive index layer 232 and the uneven surface of the uneven layer 131. Although the variable refractive index layer 232 is also in contact with the second electrode layer 150, another layer (film) may be interposed between the variable refractive index layer 232 and the second electrode layer 150.

Further, the refractive index of the variable refractive index layer 232 changes according to the applied electric field. The electric field changes according to the voltage applied between the first electrode layer 140 and the second electrode layer 150. Specifically, the variable refractive index layer 232 functions as a refractive index adjusting layer in which the refractive index in the visible light region can be adjusted by applying an electric field. For example, a DC voltage is applied between the first electrode layer 140 and the second electrode layer 150.

Since the nanoparticles 236 dispersed in the insulating liquid 235 are charged, when an electric field is applied to the refractive index variable layer 232, the nanoparticles 236 travel in the insulating liquid 235 according to the electric field distribution, and the insulating liquid It is unevenly distributed within 235. As a result, the particle distribution of the nanoparticles 236 in the variable refractive index layer 232 can be changed to have a concentration distribution of the nanoparticles 236 in the variable refractive index layer 232, so that the refractive index in the variable refractive index layer 232 can be provided. The distribution changes. That is, the refractive index of the variable refractive index layer 232 changes partially.

The thickness of the variable refractive index layer 232 is, for example, 1 μm to 100 μm, but is not limited to this. As an example, when the height of the convex portion 133 of the concave-convex layer 131 is 10 μm, the thickness of the refractive index variable layer 232 is, for example, 40 μm.

[Drive mode]
Subsequently, in the present embodiment, the details of the three drive modes executed by the control device 10 will be described.

<Daylighting mode>
First, the lighting mode will be described with reference to FIG. 14A. FIG. 14A is an enlarged cross-sectional view for explaining the lighting mode of the light distribution device 200 according to the present embodiment.

The daylighting mode is a daylighting mode in which the traveling direction of the light incident on the light distribution device 200 is bent and emitted in a direction different from the incident direction. The daylighting mode is specifically executed in the daytime if the current time is not included in the nighttime. The lighting mode is a first mode in which a first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 232.

When the light distribution device 200 is operated in the lighting mode, the control unit 22 applies a predetermined first voltage between the first electrode layer 140 and the second electrode layer 150. Specifically, the control unit 22 in-plane between the first electrode layer 140 and the second electrode layer 150 so that the potential of the second electrode layer 150 is higher than the potential of the first electrode layer 140. A uniform first voltage is applied. For example, the control unit 22 applies a positive potential to the second electrode layer 150 and a negative or zero potential to the first electrode layer 140. The first voltage is, for example, a DC voltage having a magnitude (potential difference) of several tens of volts.

The magnitude of the first voltage applied in the lighting mode is determined based on, for example, the incident angle of sunlight. For example, the control unit 22 adjusts the magnitude of the first voltage applied based on the solar altitude within a predetermined range. The smaller the magnitude of the first voltage, the closer the light distribution device 200 is to the state of being driven in the transparent mode. The larger the magnitude of the first voltage, the closer the light distribution device 200 is driven in the security mode. The refractive index of the variable refractive index layer 232 changes according to the uneven distribution state of the nanoparticles 236.

For example, as shown in FIG. 14A, since the nanoparticles 236 are positively charged, they migrate toward the first electrode layer 140 and are aggregated and unevenly distributed on the uneven layer 131 side in the refractive index variable layer 232. .. At this time, the nanoparticles 236 enter between the adjacent convex portions 133, that is, the concave portions 134 and accumulate.

As a result, as shown in FIG. 14A, a concentration distribution of nanoparticles 236 is formed in the variable refractive index layer 232. For example, in the first region 232a on the concave-convex layer 131 side, the concentration of nanoparticles 236 is high, and in the second region 232b on the second electrode layer 150 side, the concentration of nanoparticles 236 is low. Therefore, there is a difference in refractive index between the first region 232a and the second region 232b. In this embodiment, the refractive index of the nanoparticles 236 is higher than that of the insulating liquid 235. Therefore, the refractive index of the first region 232a having a high concentration of nanoparticles 236 is higher than the refractive index of the second region 232b having a low concentration of nanoparticles 236, that is, a large proportion of the insulating liquid 235. For example, the refractive index of the first region 232a is about 1.6 to about 1.8 depending on the concentration of nanoparticles 236. The refractive index of the second region 232b is about 1.4 to about 1.6 depending on the concentration of the nanoparticles 236.

In the present embodiment, since the refractive index of the convex portion 133 is 1.5, a refractive index difference (= about 0.1 to about 0.3) occurs at the interface between the convex portion 133 and the variable refractive index layer 232. .. As a result, as shown in FIG. 14A, the light L incident from the outdoor side is refracted by the side surface 133b and then reflected (totally reflected) by the side surface 133a. As a result, the light L such as sunlight incident obliquely downward is bent in the traveling direction by the light distribution device 200 and is irradiated to the ceiling surface or the like indoors. The direction of the light L emitted from the light distribution device 200 changes depending on the difference in the refractive index at the interface between the convex portion 133 and the variable refractive index layer 232. Therefore, the control unit 22 adjusts the electric field applied to the variable refractive index layer 232, that is, the magnitude of the first voltage applied to the first electrode layer 140 and the second electrode layer 150 from the light distribution device 200. The direction of the emitted light L can be changed. In this embodiment, all the light is distributed regardless of the polarization of the light L.

<Transparent mode>
Next, the transparent mode will be described with reference to FIG. 14B. FIG. 14B is an enlarged cross-sectional view for explaining the transparent mode of the light distribution device 200 according to the present embodiment.

The transparent mode is a mode in which the light incident on the light distribution device 200 is transmitted as it is. The transparent mode is an example of a third mode in which the difference in refractive index at the interface between the plurality of convex portions 133 and the variable refractive index layer 232 is substantially zero. The transparent mode is specifically executed during the day if the current time is not included at night.

When the light distribution device 200 is operated in the transparent mode, the control unit 22 does not apply a voltage between the first electrode layer 140 and the second electrode layer 150. Specifically, the control unit 22 does not apply an electric field to the variable refractive index layer 232 by making the first electrode layer 140 and the second electrode layer 150 have the same potential.

In this case, as shown in FIG. 14B, the nanoparticles 236 are substantially evenly dispersed throughout the insulating liquid 235. That is, the nanoparticles 236 are not unevenly distributed in the insulating liquid 235 and hardly form a concentration distribution. Therefore, the refractive index of the variable refractive index layer 232 becomes substantially uniform throughout the variable refractive index layer 232.

In the present embodiment, the refractive index of the variable refractive index layer 232 when the nanoparticles 236 are evenly dispersed in the insulating liquid 235 is equal to the refractive index of 1.5 of the convex portion 133. Therefore, the difference in refractive index at the interface between the convex portion 133 and the variable refractive index layer 232 becomes substantially zero.

Therefore, as shown in FIG. 14B, the light L such as sunlight incident obliquely downward passes through the light distribution device 100 as it is and irradiates the indoor floor or the like.

<Security mode>
Next, the security mode will be described with reference to FIG. 14C. FIG. 14C is an enlarged cross-sectional view for explaining the security mode of the light distribution device 200 according to the present embodiment.

The security mode is a mode in which the light passing through the light distribution device 200 from the second substrate 120 to the first substrate 110 is scattered. The security mode is an example of a second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface between the plurality of convex portions 133 and the variable refractive index layer 232. That is, in the security mode, a refractive index difference larger than the refractive index difference generated in the lighting mode is generated. Security mode is executed when the current time is included at night.

The second refractive index difference is, for example, the maximum value of the refractive index difference that can occur at the interface between the plurality of convex portions 133 and the refractive index variable layer 232. The second refractive index difference does not have to be the maximum value, but the larger the value, the higher the light scattering effect.

In the security mode, the control unit 22 applies a third voltage between the first electrode layer 140 and the second electrode layer 150, which is larger than the first voltage applied in the light distribution mode. Specifically, the third voltage is a DC voltage having the same polarity as the first voltage and a large magnitude (potential difference). The control unit 22 has a third in-plane uniform third voltage between the first electrode layer 140 and the second electrode layer 150 so that the potential of the second electrode layer 150 is higher than the potential of the first electrode layer 140. Is applied. Specifically, the magnitude of the third voltage is such that substantially all of the nanoparticles 236 dispersed in the insulating liquid 235 are aggregated on the uneven layer 131 side.

In this case, as shown in FIG. 14C, the refractive index variable layer 232 includes the first region 232a in which the nanoparticles 236 are aggregated and the second region 232b in which the nanoparticles 236 are hardly contained, as in the lighting mode. Is formed. The concentration of nanoparticles 236 in the first region 232a in the security mode is higher than the concentration of nanoparticles 236 in the first region 232a in the lighting mode. The refractive index of the first region 232a in the security mode is the maximum value of the refractive index that can occur in the variable refractive index layer 232. Specifically, the refractive index of the first region 232a is substantially equal to the refractive index 2.1 of the nanoparticles 236. As a result, the difference between the refractive index 2.1 of the first region 232a of the variable refractive index layer 232 and the refractive index 1.5 of the convex portion 133 becomes a maximum value of 0.6.

Therefore, as shown in FIG. 14C, the light L incident on the second substrate 120 in the horizontal direction from the indoor side is reflected (totally reflected) by the side surfaces 133a and 133b of the convex portion 133 and scattered in various directions. ..

As described above, when an attempt is made to look indoors from the outdoor side via the light distribution device 200, the light L from the indoors is scattered in the security mode. Therefore, the light distribution device 200 functions like frosted glass, and the indoor appearance can be obscured from the outside. The larger the difference in refractive index between the convex portion 133 and the variable refractive index layer 232, the higher the scattering effect, and therefore the higher the security effect. In this embodiment, all the light is scattered regardless of the polarization of the light L.

(Other)
The control device, the light distribution control system, and the light distribution control method of the light distribution device according to the present invention have been described above based on the above-described embodiment, but the present invention is limited to the above-described embodiment. is not.

For example, the liquid crystal molecule 135 may be a negative type liquid crystal molecule. Further, for example, the refractive index of the nanoparticles 236 may be lower than the refractive index of the insulating liquid 235. The lighting mode, the transparency mode, and the security mode can be realized by appropriately adjusting the applied voltage according to the refractive index and polarity of the liquid crystal molecules or nanoparticles.

Further, for example, in the above embodiment, the nanoparticles 236 are positively charged, but the present invention is not limited to this. That is, the nanoparticles 236 may be negatively charged. In this case, a positive potential is applied to the first electrode layer 140 and a negative potential is applied to the second electrode layer 150 to apply a DC voltage between the first electrode layer 140 and the second electrode layer 150. It is good to do.

Further, the plurality of nanoparticles 236 may include a plurality of types of nanoparticles having different optical characteristics. For example, it may contain positively charged transparent first nanoparticles and negatively charged opaque (such as black) second nanoparticles. For example, the light distribution device 100 or 200 may have a light-shielding function by aggregating and unevenly distributing the second nanoparticles.

Further, in the above embodiment, the convex portion 133 constituting the concave-convex layer 131 is a long triangular prism having a triangular cross-sectional shape, but the present invention is not limited to this. For example, the convex portion 133 may be an elongated substantially quadrangular prism having a substantially trapezoidal cross section. Further, the cross-sectional shape of the side surface of the convex portion 133 is not limited to a straight line, but may be a curved line or a saw shape. Further, each of the plurality of convex portions 133 is not limited to one elongated member extending in the x-axis direction, and may be partially divided in the x-axis direction. That is, the plurality of convex portions 133 may be provided so as to be dispersed in a dot shape.

Further, in the above embodiment, the heights of the plurality of convex portions 133 are constant, but the height is not limited to this. For example, the heights of the plurality of convex portions 133 may be randomly different. Alternatively, the spacing between the protrusions 133 may be randomly different, or both the height and the spacing may be random.

Further, in the above embodiment, sunlight is exemplified as the light incident on the light distribution device 100, but the present invention is not limited to this. For example, the light incident on the light distribution device 100 may be the light emitted by a light emitting device such as a lighting fixture.

Further, in the above embodiment, the light distribution device 100 or 200 is arranged on the window so that the longitudinal direction of the convex portion 133 is the x-axis direction, but the present invention is not limited to this. For example, the light distribution device 100 or 200 may be arranged in the window so that the longitudinal direction of the convex portion 133 is the z-axis direction.

Further, in the above embodiment, the light distribution device 100 or 200 is attached to the window, but the light distribution device 100 or 200 may be used as the window itself of the building. Further, the light distribution device 100 or 200 is not limited to the case where it is installed in a window of a building, and may be installed in, for example, a window of a car.

Further, in the above embodiment, all or a part of the components such as the control unit may be configured by dedicated hardware, or may be realized by executing a software program suitable for each component. May be good. Each component may be realized by a program execution unit such as a CPU (Central Processing Unit) or a processor reading and executing a software program recorded on a recording medium such as an HDD (Hard Disk Drive) or a semiconductor memory. Good.

Further, a component such as a control unit may be composed of one or a plurality of electronic circuits. The one or more electronic circuits may be general-purpose circuits or dedicated circuits, respectively.

The one or more electronic circuits may include, for example, a semiconductor device, an IC (Integrated Circuit), an LSI (Large Scale Integration), or the like. The IC or LSI may be integrated on one chip or may be integrated on a plurality of chips. Here, it is called IC or LSI, but the name changes depending on the degree of integration, and it may be called system LSI, VLSI (Very Large Scale Integration), or ULSI (Ultra Large Scale Integration). An FPGA (Field Programmable Gate Array) programmed after the LSI is manufactured can also be used for the same purpose.

In addition, general or specific aspects of the present invention may be realized in a system, device, method, integrated circuit or computer program. Alternatively, it may be realized by a computer-readable non-temporary recording medium such as an optical disk, HDD or semiconductor memory in which the computer program is stored. Further, it may be realized by any combination of a system, an apparatus, a method, an integrated circuit, a computer program and a recording medium.

In addition, it is realized by arbitrarily combining the components and functions in each embodiment within the range obtained by applying various modifications to each embodiment and the gist of the present invention. Forms are also included in the present invention.

1, 2, 3, 4 Light distribution control system 10, 10a, 10b, 10c Control device 20, 20a, 20b, 20c Acquisition unit 22, 22a, 22b, 22c Control unit 100, 200 Light distribution device 130, 230 Light distribution layer 131 Concavo-convex layer 132, 232 Variable refractive index layer 133 Convex portion 133a, 133b Side surface (interface)
134 recess

Claims (9)

An acquisition unit that acquires time information indicating the time,
A control unit that controls a light distribution device including a light distribution layer that distributes incident light based on the time information is provided.
The light distribution layer is
Concavo-convex layer with multiple convex parts,
It is provided with a variable refractive index layer which is arranged so as to fill the space between the plurality of convex portions and whose refractive index changes according to an applied electric field.
The control unit
A first mode in which a first refractive index difference is generated at an interface between the plurality of convex portions and the variable refractive index layer,
It has a second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface between the plurality of convex portions and the variable refractive index layer.
A control device for a light distribution device that executes the second mode when the time indicated by the time information is included in the nighttime. The control device for a light distribution device according to claim 1, wherein the second refractive index difference is the maximum value of the refractive index difference that can occur at the interface between the plurality of convex portions and the variable refractive index layer. The control of the light distribution device according to claim 1 or 2, wherein the control unit further has a third mode in which the difference in refractive index at the interface between the plurality of convex portions and the variable refractive index layer is substantially zero. apparatus. The acquisition unit further acquires outdoor illuminance information indicating outdoor illuminance, and obtains outdoor illuminance information.
The control device for a light distribution device according to any one of claims 1 to 3, wherein the control unit executes the second mode when the illuminance indicated by the outdoor illuminance information is equal to or less than a predetermined threshold value. The acquisition unit further acquires outdoor illuminance information indicating outdoor illuminance and indoor illuminance information indicating indoor illuminance.
The light distribution device according to any one of claims 1 to 3, wherein the control unit executes the second mode when the illuminance indicated by the indoor illuminance information is larger than the illuminance indicated by the outdoor illuminance information. Control device. The acquisition unit further acquires operation information for selecting the second mode from the terminal device.
The control device for a light distribution device according to any one of claims 1 to 5, wherein the control unit executes the second mode when the acquisition unit acquires the operation information. The control device for the light distribution device according to any one of claims 1 to 6,
A light distribution control system including the light distribution device. The acquisition step to acquire the time information indicating the time, and
A control step for controlling a light distribution device including a light distribution layer that distributes incident light based on the time information is included.
The light distribution layer is
Concavo-convex layer with multiple convex parts,
It is provided with a variable refractive index layer which is arranged so as to fill the space between the plurality of convex portions and whose refractive index changes according to an applied electric field.
In the control step
A first mode in which a first refractive index difference is generated at an interface between the plurality of convex portions and the variable refractive index layer,
A second mode in which a second refractive index difference larger than the first refractive index difference is generated at the interface between the plurality of convex portions and the variable refractive index layer is selectively executed.
A light distribution control method for executing the second mode when the time indicated by the time information is included at night. A program for causing a computer to execute the light distribution control method according to claim 8.

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