Lighting system

Abstract

The lighting system includes: a light source; a liquid crystal cell that changes a light distribution angle of light emitted from the light source; and a control device for controlling the gradation of the light distribution angle, the liquid crystal cell comprising: a first substrate on which first transparent electrodes and second transparent electrodes respectively extending in a first direction are alternately provided; a second substrate alternately provided with third and fourth transparent electrodes extending in a second direction intersecting the first direction, respectively; and a liquid crystal layer between the first substrate and the second substrate, the control device comprising: a communication unit that receives gradation information of the light distribution angle from an information communication terminal; a storage unit that stores a weighting coefficient that associates the amount of change in the light distribution angle with the change in the gradation of the light distribution angle; and a control section that calculates first to fourth voltages input to the first to fourth transparent electrodes on the basis of the gradation information and the weighting coefficient.

Description

Technical Field

[0001] One embodiment of the present invention relates to a lighting system that controls a light distribution angle of light emitted from a light source using liquid crystal. Background Art

[0002] In the control of light distribution of lighting devices, a method of adjusting the lens position by combining lenses or a method of adjusting the focus position by a motor has been proposed (for example, see Patent Document 1). On the other hand, in recent years, the development of lighting devices using an optical element, a so-called liquid crystal lens, which uses the principle of changing the refractive index of liquid crystal by adjusting the voltage applied to the liquid crystal has been underway (for example, see Technical Document 2).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-39026

[0006] Patent Document 2: Japanese Patent Application Publication No. 2012-69409 Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] In a lighting device using a liquid crystal lens, light distribution is controlled by applying a voltage to the liquid crystal. However, since the refractive index of the liquid crystal does not change constantly with respect to the voltage, it is difficult to control light distribution and this does not match the user's operating sense.

[0009] In view of the above problems, one object of one embodiment of the present invention is to provide a lighting system capable of controlling light distribution in accordance with a user's operational sense.

[0010] Solutions for solving technical problems

[0011] An illumination system according to one embodiment of the present invention includes: a light source; a liquid crystal unit that changes the light distribution angle of light emitted from the light source; and a control device that controls the grayscale of the light distribution angle, wherein the liquid crystal unit includes: a first substrate that is alternately provided with first transparent electrodes and second transparent electrodes that extend in a first direction, respectively; a second substrate that is alternately provided with third transparent electrodes and fourth transparent electrodes that extend in a second direction that intersects the first direction, respectively; and a liquid crystal layer between the first substrate and the second substrate, and the control device includes: a communication unit that receives grayscale information of the light distribution angle from an information communication terminal; a storage unit that stores a weighting coefficient that associates a change in the light distribution angle with a change in the grayscale of the light distribution angle; and a control unit that calculates a first voltage input to the first transparent electrode, a second voltage input to the second transparent electrode, a third voltage input to the third transparent electrode, and a fourth voltage input to the fourth transparent electrode based on the grayscale information and the weighting coefficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram showing the structure of a lighting system involved in one embodiment of the present invention.

[0013] Figure 2 This is a block diagram showing the configuration of a lighting system according to an embodiment of the present invention.

[0014] Figure 3A It is a schematic cross-sectional view showing the structure of a lighting system according to an embodiment of the present invention.

[0015] Figure 3B It is a schematic cross-sectional view showing the structure of a lighting system according to an embodiment of the present invention.

[0016] Figure 4A This is a schematic plan view showing an electrode pattern of a liquid crystal cell included in an optical element of an illumination system according to an embodiment of the present invention.

[0017] Figure 4B This is a schematic plan view showing an electrode pattern of a liquid crystal cell included in an optical element of an illumination system according to an embodiment of the present invention.

[0018] Figure 5A It is a schematic diagram for explaining the optical characteristics of a liquid crystal cell included in the optical element of the illumination system according to one embodiment of the present invention.

[0019] Figure 5B It is a schematic diagram for explaining the optical characteristics of a liquid crystal cell included in the optical element of the illumination system according to one embodiment of the present invention.

[0020] Fig. 6AThis is a timing chart of signals input to transparent electrodes of an optical element in order to control a light distribution shape in the lighting system according to one embodiment of the present invention.

[0021] Figure 6B This is a timing chart of signals input to transparent electrodes of an optical element in order to control a light distribution shape in the lighting system according to one embodiment of the present invention.

[0022] Figure 6C This is a timing chart of signals input to transparent electrodes of an optical element in order to control a light distribution shape in the lighting system according to one embodiment of the present invention.

[0023] Fig. 7A It is a schematic diagram for explaining the definition of the luminous intensity distribution angle and the half width at half maximum in the lighting system according to one embodiment of the present invention.

[0024] Figure 7B It is a schematic diagram for explaining the definition of the light distribution angle and the half width at half maximum in the lighting system according to one embodiment of the present invention.

[0025] Figure 8 This is a graph showing the correlation between the voltage applied to the transparent electrode of the optical element and the half width at half maximum in the lighting system according to one embodiment of the present invention.

[0026] Fig. 9 This is a flowchart illustrating grayscale control processing in a lighting system according to an embodiment of the present invention.

[0027] Fig. 10A This is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=1 in the lighting system according to the embodiment of the present invention.

[0028] Fig. 10B This is a graph showing the correlation between the grayscale and the voltage applied to the transparent electrode when the weighting coefficient b=1 in the lighting system according to the embodiment of the present invention.

[0029] Fig.11A This is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=2 in the lighting system according to the embodiment of the present invention.

[0030] Fig. 11B This is a graph showing the correlation between grayscale and voltage applied to a transparent electrode when the weighting coefficient b=2 in the lighting system according to the embodiment of the present invention.

[0031] Fig. 12AThis is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=3 in the lighting system according to the embodiment of the present invention.

[0032] Fig. 12B This is a graph showing the correlation between grayscale and voltage applied to the transparent electrode when the weighting coefficient b=3 in the lighting system according to the embodiment of the present invention.

[0033] Fig.13 This is a block diagram illustrating a lighting system according to an embodiment of the present invention.

[0034] Fig.14 This is a block diagram illustrating a lighting system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] Hereinafter, each embodiment of the present invention will be described with reference to the drawings, etc. However, the present invention can be implemented in various forms within the scope of the gist of the technical concept, and is not to be construed as being limited to the description of the following exemplary embodiments.

[0036] In order to make the description clearer, the drawings sometimes schematically show the width, thickness, shape, etc. of each part compared to the actual form, but this is only an example, and the shape of the drawings itself does not limit the interpretation of the present invention. In addition, in the drawings, for elements having the same function as the elements described in the drawings that have appeared in the specification, even in other drawings, the same reference numerals are sometimes marked and repeated descriptions are omitted.

[0037] When a certain film is processed to form a plurality of structures, each structure may have different functions and effects, and each structure may have different bases. However, the plurality of structures are derived from films formed as the same layer in the same process and have the same material. Therefore, the plurality of films are defined as existing in the same layer.

[0038] When expressing a form in which another structure is arranged on a certain structure, when it is simply expressed as "on", unless otherwise specified, it includes both a case in which the other structure is arranged directly above the certain structure and a case in which the other structure is arranged above the certain structure further separated from the other structure.

[0039] <First Embodiment>

[0040] Reference Figure 1 to Figure 12B , a lighting system 1 according to an embodiment of the present invention is described.

[0041] [1. Structure of lighting system 1]

[0042] Figure 1 Schematic diagram showing the structure of a lighting system 1 according to an embodiment of the present invention. Figure 1 As shown, the lighting system 1 includes an optical element 10 , a light source 20 , a control device 30 and an information communication terminal 40 .

[0043] The optical element 10 includes four liquid crystal cells 100 (a first liquid crystal cell 100-1, a second liquid crystal cell 100-2, a third liquid crystal cell 100-3, and a fourth liquid crystal cell 100-4). In the optical element 10, the first liquid crystal cell 100-1, the second liquid crystal cell 100-2, the third liquid crystal cell 100-3, and the fourth liquid crystal cell 100-4 are stacked in sequence along the z-axis direction from the side close to the light source 20. In addition, the structure of the optical element 10 including four liquid crystal cells 100 is described below, but the number of liquid crystal cells 100 included in the optical element 10 is not limited to four. The optical element 10 only needs to include at least two liquid crystal cells 100. The details of the structure of the optical element 10 are described later.

[0044] The light source 20 emits light to the optical element 10. The light emitted from the light source 20 is incident on the first liquid crystal unit 100-1 and emitted from the fourth liquid crystal unit 100-4. In the lighting system 1, the diffusion and polarization of light are controlled by the four liquid crystal units included in the optical element 10, so that the diffusion (light distribution) of the light emitted from the fourth liquid crystal unit 100-4 can be changed. As the light source 20, for example, light emitting diodes (LEDs) can be used, but it is not limited to this. The light source 20 can be any element or device that can emit light.

[0045] The control device 30 is connected to the optical element 10 and the light source 20 to control the optical element 10 and the light source 20. The control device 30 includes, for example, a central processing unit (CPU), a microprocessor (MPU), an integrated circuit (IC), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a random access memory (RAM). The details of the structure of the control device 30 will be described later.

[0046] The information communication terminal 40 is, for example, a mobile phone, a smart phone, a tablet computer, or a personal computer, but is not limited thereto. The information communication terminal 40 is connected to the control device 30 via a network NW so as to be able to communicate. The network NW can be wired or wireless. However, in the case where the information communication terminal 40 is a portable terminal, the network NW is preferably wireless. The network NW is a LAN (Local Area Network) or the Internet, but is not limited thereto. In addition, the network NW may also be a network via a communication base station managed by a communication operator. In addition, the details of the structure of the information communication terminal 40 are described later.

[0047] The user can set the light distribution of light emitted from the light source 20 using the information communication terminal 40. That is, in the lighting system 1, based on the user input information from the information communication terminal 40, the control device 30 can control the optical element 10 and the light source 20 to change the light distribution of light emitted from the light source 20.

[0048] Figure 2 1 is a block diagram showing the structure of a lighting system 1 according to an embodiment of the present invention. Figure 2 As shown, the control device 30 includes a communication unit 310, a light source control unit 320, an optical element control unit 330, and a storage unit 340. In addition, the information communication terminal 40 includes a communication unit 410, a display unit 420, and an input unit 430.

[0049] The communication unit 310 is a communication interface capable of transmitting and receiving data or information. The communication unit 310 is, for example, a LAN module or a Wi-Fi (registered trademark) module.

[0050] The light source control unit 320 controls the operation of the light source 20. The control device 30 can make the light source control unit 320 function by executing a predetermined program. For example, the light source control unit 320 controls the on / off of the power of the light source 20 based on the user input information sent from the information communication terminal 40. In addition, the light source control unit 320 adjusts the light amount or color temperature of the light source 20 based on the user input information.

[0051] The optical element control unit 330 controls the optical element 10 to change the grayscale of the lighting mode, the light distribution shape, and the light distribution angle. The control device 30 can make the optical element control unit 330 function by executing a predetermined program. For example, the optical element control unit 330 calculates the voltage for controlling the optical element 10 based on the user input information sent from the information communication terminal 40, and inputs a signal including the calculated voltage to the liquid crystal unit 100. In the lighting system 1, the grayscale of the light distribution can be changed according to the lighting mode. In addition, the diffusion degree of the emitted light in the lighting system is referred to as grayscale for explanation below. For this grayscale, the grayscale can be set in multiple levels from the case where the expansion of the emitted light is the smallest (there is no expansion of the emitted light, or the emitted light from the light source is directly emitted) to the case where the maximum is the largest. The grayscale can be set to 8 levels, 16 levels, 32 levels, 64 levels, 128 levels, or 256 levels, etc. Alternatively, a configuration may be applied in which the light spreading state is set to 0% (a state where there is no light spreading or a state where light from a light source is directly irradiated) to 100% (a state where light spreading is maximal) instead of grayscale.

[0052] The lighting mode may be, for example, a wide-angle lighting mode that illuminates a wide range like a downlight, or an angle lighting mode that illuminates a narrow range like a spotlight, but is not limited thereto. Details of the grayscale control of light distribution by the optical element control unit 330 will be described later.

[0053] The storage unit 340 is a memory capable of storing data or information. The storage unit 340 is, for example, a hard disk drive (HDD), a solid state drive (SSD), a read only memory (ROM), a random access memory (RAM), or a flash memory. The storage unit 340 stores a plurality of weighting coefficients 341 corresponding to a plurality of lighting modes.

[0054] Since the communication unit 410 has the same configuration as the communication unit 310 , the description thereof will be omitted.

[0055] The display unit 420 includes a screen and is a display interface capable of displaying images on the screen, etc. The display unit is, for example, a liquid crystal display device or an OLED display device.

[0056] The input unit 430 is a user interface that allows the user to input data or information. The input unit 430 is, for example, a button, a keyboard, or a mouse that can accept user operations. In addition, the input unit 430 can generate user input information based on the user operation. The user input information is, for example, lighting mode information including the lighting mode selected by the user, and grayscale information including the grayscale selected by the user. In addition, the input unit 430 can also be a touch screen integrated with the display unit 420.

[0057] [2. Structure of the optical element 10]

[0058] Figure 3A as well as Figure 3B Each of them is a schematic cross-sectional view showing the structure of a lighting system 1 according to an embodiment of the present invention. Specifically, Figure 3A So Figure 1 A cross-sectional view of the optical element 10 cut along the line A1-A2, Figure 3B So Figure 1 A cross-sectional view of the optical element 10 taken along line B1 - B2.

[0059] like Figure 3A as well as Figure 3B As shown, the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4 respectively include a first substrate 110-1, a second substrate 110-2, a plurality of first transparent electrodes 120-1, a plurality of second transparent electrodes 120-2, a plurality of third transparent electrodes 120-3, a plurality of fourth transparent electrodes 120-4, a first alignment film 130-1, a second alignment film 130-2, a sealing material 140 and a liquid crystal layer 150. The first transparent electrodes 120-1 and the second transparent electrodes 120-2 are alternately arranged on the first substrate 110-1. That is, the plurality of first transparent electrodes 120-1 and the plurality of second transparent electrodes 120-2 are arranged in a comb-tooth shape. In addition, the first alignment film 130-1 is arranged on the first substrate 110-1 in a manner of covering the first transparent electrode 120-1 and the second transparent electrode 120-2. The third transparent electrode 120-3 and the fourth transparent electrode 120-4 are alternately arranged on the second substrate 110-2. That is, the plurality of third transparent electrodes 120-1 and the plurality of fourth transparent electrodes 120-4 are arranged in a comb-tooth shape. In addition, the second orientation film 130-2 is provided on the second substrate 110-2 in a manner covering the third transparent electrode 120-3 and the fourth transparent electrode 120-4. The first substrate 110-1 and the second substrate 110-2 are arranged in a manner that the first transparent electrode 120-1 and the second transparent electrode 120-2 are opposite to the third transparent electrode 120-3 and the fourth transparent electrode 120-4, and are bonded via a sealing material 140 provided at the periphery of the first substrate 110-1 and the second substrate 110-2. Liquid crystal is sealed in a space surrounded by the first substrate 110-1 (more specifically, the first orientation film 130-1), the second substrate 110-2 (more specifically, the second orientation film 130-2), and the sealing material 140, and a liquid crystal layer 150 is provided between the first substrate 110-1 and the second substrate 110-2.

[0060] An optical elastic resin layer 160 is provided between the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2. Similarly, an optical elastic resin layer 160 is provided between the second liquid crystal cell 100-2 and the third liquid crystal cell 100-3, and between the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4. As the optical elastic resin layer 160, for example, an adhesive including a light-transmitting acrylic resin can be used. That is, the optical elastic resin layer 160 can adhere and fix two adjacent liquid crystal cells 100.

[0061] As the first substrate 110-1 and the second substrate 110-2, a glass substrate, a quartz substrate, a sapphire substrate or other light-transmitting rigid substrates are used, respectively. In addition, as the first substrate 110-1 and the second substrate 110-2, a polyimide resin substrate, an acrylic resin substrate, a siloxane resin substrate, a fluororesin substrate or other light-transmitting flexible substrates are used, respectively.

[0062] The first transparent electrode 120-1, the second transparent electrode 120-2, the third transparent electrode 120-3, and the fourth transparent electrode 120-4 function as electrodes for forming an electric field in the liquid crystal layer 150. For example, transparent conductive materials such as indium tin oxide (ITO) or indium zinc oxide (IZO) are used as the first transparent electrode 120-1, the second transparent electrode 120-2, the third transparent electrode 120-3, and the fourth transparent electrode 120-4.

[0063] In the first liquid crystal unit 100-1 and the second liquid crystal unit 100-2, the first transparent electrode 120-1 and the second transparent electrode 120-2 extend along the x-axis direction, and the third transparent electrode 120-3 and the fourth transparent electrode 120-4 extend along the y-axis direction. In addition, in the third liquid crystal unit 100-3 and the fourth liquid crystal unit 100-4, the first transparent electrode 120-1 and the second transparent electrode 120-2 extend along the y-axis direction, and the third transparent electrode 120-3 and the fourth transparent electrode 120-4 extend along the x-axis direction.

[0064] In addition, below, when the first to fourth transparent electrodes 120 - 1 to 120 - 4 are not particularly distinguished, they may be described as the transparent electrode 120 .

[0065] The first alignment film 130-1 and the second alignment film 130-2 respectively align the liquid crystal molecules in the liquid crystal layer 150 in a predetermined direction. As the first alignment film 130-1 and the second alignment film 130-2, polyimide resin or the like is used respectively. In addition, the first alignment film 130-1 and the second alignment film 130-2 can each be given an alignment characteristic by an alignment treatment such as a rubbing method or a photo-alignment method. The rubbing method is a method of rubbing the surface of the alignment film in one direction. In addition, the photo-alignment method is a method of irradiating the alignment film with linearly polarized ultraviolet rays.

[0066] The first alignment film 130-1 is aligned in such a way that the liquid crystal molecules on the first substrate 110-1 side of the liquid crystal layer 150 are aligned in a direction perpendicular to the extension direction of the first transparent electrode 120-1 and the second transparent electrode 120-2. In addition, the second alignment film 130-2 is aligned in such a way that the liquid crystal molecules on the second substrate 110-2 side of the liquid crystal layer 150 are aligned in a direction perpendicular to the extension direction of the third transparent electrode 120-3 and the fourth transparent electrode 120-4. Therefore, in the first liquid crystal unit 100-1 and the second liquid crystal unit 100-2, the long axes of the liquid crystal molecules on the first substrate 110-1 side are aligned in the y-axis direction, and the long axes of the liquid crystal molecules on the second substrate 110-2 side are aligned in the x-axis direction. In addition, in the third liquid crystal unit 100-3 and the fourth liquid crystal unit 100-4, the long axes of the liquid crystal molecules on the first substrate 110-1 side are aligned in the x-axis direction, and the long axes of the liquid crystal molecules on the second substrate 110-2 side are aligned in the y-axis direction. Furthermore, in the above description, the alignment direction of the liquid crystal molecules is orthogonal to the extension direction of the transparent electrode 120 , but the alignment direction of the liquid crystal molecules and the extension direction of the transparent electrode 120 may intersect at an angle other than orthogonal, for example, an angle greater than 85 degrees and less than 90 degrees.

[0067] An adhesive material such as epoxy resin or acrylic resin is used as the sealing material 140. The adhesive material may be an ultraviolet curing type or a thermosetting type.

[0068] The liquid crystal layer 150 can refract the transmitted light or change the polarization state of the transmitted light according to the orientation state of the liquid crystal molecules. As the liquid crystal of the liquid crystal layer 150, nematic liquid crystal or the like is used. The liquid crystal described in this embodiment is a positive type, but a negative type structure can also be applied by changing the orientation direction of the liquid crystal molecules in a state where no voltage is applied to the transparent electrode 120. In addition, it is preferable that a chiral agent that imparts twist to the liquid crystal molecules is contained in the liquid crystal.

[0069] [3. Electrode Pattern of Liquid Crystal Cell 100]

[0070] Figure 4A as well as Figure 4BEach of them is a schematic top view showing an electrode pattern of a liquid crystal unit 100 included in an optical element 10 of an illumination system 1 according to an embodiment of the present invention. Specifically, Figure 4A is a top view showing an electrode pattern formed on the first substrate 110 - 1 of the first liquid crystal unit 100 - 1, Figure 4B 1 is a plan view showing an electrode pattern formed on the second substrate 110 - 2 of the first liquid crystal cell 100 - 1 .

[0071] like Figure 4A As shown, a first connection pad 121-1 and a second connection pad 121-2 are provided on the first substrate 110-1. A plurality of first transparent electrodes 120-1 are electrically connected to the first connection pad 121-1. A plurality of second transparent electrodes 120-2 are electrically connected to the second connection pad 121-2.

[0072] like Figure 4B As shown, a third connection pad 121-3, a fourth connection pad 121-4, a first terminal 122-1, a second terminal 122-2, a third terminal 122-3 and a fourth terminal 122-4 are provided on the second substrate 110-2. A plurality of third transparent electrodes 120-3 are electrically connected to the third terminal 122-3. A plurality of fourth transparent electrodes 120-4 are electrically connected to the fourth terminal 122-4. In addition, the third connection pad 121-3 is electrically connected to the first terminal 122-1. The fourth connection pad 121-4 is electrically connected to the second terminal 122-2.

[0073] When the first substrate 110-1 and the second substrate 110-2 are bonded to each other, the first connection pad 121-1 and the second connection pad 121-2 overlap with the third connection pad 121-3 and the fourth connection pad 121-4, respectively. A conductive material such as silver paste is provided between the first connection pad 121-1 and the third connection pad 121-3, and the first connection pad 121-1 and the third connection pad 121-3 are electrically connected via the conductive material. Similarly, a conductive material is also provided between the second connection pad 121-2 and the fourth connection pad 121-4, and the second connection pad 121-2 and the fourth connection pad 121-4 are electrically connected via the conductive material. Thus, the first transparent electrode 120-1 and the second transparent electrode 120-2 on the first substrate 110-1 are electrically connected to the first terminal 122-1 and the second terminal 122-2, respectively.

[0074] The electrode pattern of the second liquid crystal cell 100-2 is the same as that of the first liquid crystal cell 100-1. The electrode pattern structures of the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4 are the same as that of the first liquid crystal cell 100-1 except that the extending direction of the transparent electrode 120 is rotated 90 degrees.

[0075] In the liquid crystal cell 100, the first terminal 122-1 to the fourth terminal 122-4 on the second substrate 110-2 are exposed from the first substrate 110-1. In each of the first liquid crystal cells 100-1 to the fourth liquid crystal cells 100-4, a flexible printed circuit (FPCs) 170 (see Figure 1 ). The FPCs 170 are electrically connected to the control device 30. Therefore, the control device 30 can input signals to the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of the liquid crystal unit 100 through the FPCs 170, respectively, to control the optical element 10.

[0076] [4. Optical Characteristics of Liquid Crystal Cell 100]

[0077] Figure 5A as well as Figure 5B Each of them is a schematic diagram for explaining the optical characteristics of the liquid crystal unit 100 included in the optical element 10 of the lighting system 1 according to one embodiment of the present invention. Specifically, Figure 5A 1 shows the liquid crystal cell 100 in a state where no voltage is applied to the transparent electrode 120. Figure 5B The liquid crystal cell 100 is shown in a state where a voltage is applied to the transparent electrode 120 .

[0078] like Figure 5A As shown, the liquid crystal molecules on the first substrate 110-1 side of the liquid crystal layer 150 are oriented in the y-axis direction, and the liquid crystal molecules on the second substrate 110-2 side of the liquid crystal layer 150 are oriented in the x-axis direction. Therefore, in a state where no voltage is applied to the first transparent electrode 120-1 to the fourth transparent electrode 120-4, the liquid crystal molecules in the liquid crystal layer 150 are oriented in a manner of twisting 90° in the c-axis direction as they move from the first substrate 110-1 toward the second substrate 110-2. In addition, the light passing through the liquid crystal layer 150 rotates the polarization plane (polarization axis or direction of polarized light component) by 90° according to the orientation of the liquid crystal molecules. More specifically, the P-polarized light component incident on the liquid crystal unit 100 becomes the S-polarized light component through the liquid crystal layer 150 of the liquid crystal unit 100, and the S-polarized light component incident on the liquid crystal unit 100 becomes the P-polarized light component. Such a phenomenon of polarized light component migration can be called optical rotation.

[0079] On the other hand, when a voltage is applied so as to generate a potential difference between two adjacent transparent electrodes 120, an electric field (hereinafter referred to as a "lateral electric field") is generated between the two adjacent transparent electrodes 120, and the orientation of the liquid crystal molecules changes. Figure 5BAs shown, the liquid crystal molecules in the liquid crystal layer 150 are oriented in a manner of twisting 90° in the c-axis direction as they move from the first substrate 110-1 toward the second substrate 110-2, and the liquid crystal molecules near the first substrate 110-1 side are arranged in a convex arc shape relative to the first substrate 110-1 by the lateral electric field between the first transparent electrode 120-1 and the second transparent electrode 120-2, and the liquid crystal molecules near the second substrate 110-2 side are arranged in a convex arc shape relative to the second substrate 110-2 by the lateral electric field between the third transparent electrode 120-3 and the fourth transparent electrode 120-4. The liquid crystal molecules arranged in a convex arc shape have a refractive index distribution, and light having the same polarization direction as the orientation direction of the liquid crystal molecules is diffused. In addition, since the interval between the first substrate 110-1 and the second substrate 110-2, that is, the cell gap d, is sufficiently larger than the distance between two adjacent transparent electrodes (for example, 10μm≤d≤30μm), the orientation of the liquid crystal molecules located near the center between the first substrate 110-1 and the second substrate 110-2 is almost unchanged.

[0080] The light emitted from the light source 20 includes a polarized light component in the x-axis direction (hereinafter referred to as the "P-polarized light component") and a polarized light component in the y-axis direction (hereinafter referred to as the "S-polarized light component"), but for convenience, the light emitted from the light source 20 is divided into a first light 1000-1 having a P-polarized light component and a second light 1000-2 having an S-polarized light component for explanation below.

[0081] Since the P-polarized light component of the first light 1000-1 incident from the first substrate 110-1 side is different from the alignment direction of the liquid crystal molecules on the first substrate 110-1 side, the first light 1000-1 is not diffused (refer to Figure 5B In addition, the first light 1000-1 undergoes optical rotation while passing through the liquid crystal layer 150, and the polarized light component changes from the P polarized light component to the S polarized light component. Since the S polarized light component of the first light 1000-1 is different from the orientation direction of the liquid crystal molecules on the second substrate 110-2 side, the first light 1000-1 does not diffuse (refer to Figure 5B (2) in the figure).

[0082] Since the S-polarized light component of the second light 1000-2 incident from the first substrate 110-1 side is aligned in the same direction as the liquid crystal molecules on the first substrate 110-1 side, the second light 1000-2 diffuses in the y-axis direction according to the refractive index distribution of the liquid crystal molecules (refer to Figure 5B(3) in FIG. 1 ). In addition, the second light 1000-2 undergoes optical rotation while passing through the liquid crystal layer 150, and the polarized light component changes from the S polarized light component to the P polarized light component. Since the P polarized light component of the second light 1000-2 is aligned in the same direction as the liquid crystal molecules on the second substrate 110-2 side, the second light 1000-2 diffuses in the x-axis direction according to the refractive index distribution of the liquid crystal molecules (refer to FIG. Figure 5B (4) in the figure).

[0083] [5.Light distribution control]

[0084] [5-10. Control of light distribution shape]

[0085] By controlling the voltage applied to the first to fourth transparent electrodes 120 - 1 , 120 - 4 of each of the first to fourth liquid crystal cells 100 - 1 , 100 - 4 , the light distribution shape of light passing through the optical element 10 can be changed.

[0086] Figure 6A to Figure 6C They are respectively timing diagrams of signals input to the transparent electrode 120 of the optical element 10 in order to control the light distribution shape in the lighting system 1 involved in one embodiment of the present invention. In the following, for convenience, the high voltage is set to +αV (or -βV), the low voltage is set to -αV (or βV), and the intermediate voltage is set to 0V for explanation. However, the high voltage, the low voltage and the intermediate voltage are not limited to this. The high voltage can be any voltage greater than the low voltage and the intermediate voltage. In addition, the intermediate voltage can be any voltage between the high voltage and the low voltage. For example, the high voltage, the low voltage and the intermediate voltage can be 30V, 0V and 15V, respectively.

[0087] The voltage included in the signal input to the transparent electrode 120 is a rectangular wave of repeated high voltage and low voltage, or a constant intermediate voltage, but is not limited thereto.

[0088] exist Figure 6A to Figure 6C1 and 2 show a first signal S1, a second signal S2, a third signal S3, and a fourth signal. The first signal S1 is input to the first transparent electrode 120-1 of the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2, and the third transparent electrode 120-3 of the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4. The second signal S2 is input to the second transparent electrode 120-2 of the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2, and the fourth transparent electrode 120-4 of the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4. The third signal S3 is input to the third transparent electrode 120-3 of the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2, and the first transparent electrode 120-1 of the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4. The fourth signal S4 is input to the fourth transparent electrodes 120 - 4 of the first and second liquid crystal cells 100 - 1 and 100 - 2 , and the second transparent electrodes 120 - 2 of the third and fourth liquid crystal cells 100 - 3 and 100 - 4 .

[0089] exist Fig. 6A In the case of the timing diagram shown in FIG. 1 , a lateral electric field is generated between two adjacent transparent electrodes 120 extending in the y-axis direction. In this case, the liquid crystal molecules whose long axes are oriented in the x-axis direction are arranged in a convex arc shape. Therefore, the light passing through the optical element 10 diffuses in the x-axis direction in each of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4. Fig. 6A In the timing chart shown, a linear light distribution extending in the x-axis direction can be obtained.

[0090] exist Figure 6B In the case of the timing diagram shown in FIG. 1 , a lateral electric field is generated between two adjacent transparent electrodes 120 extending in the x-axis direction. In this case, the liquid crystal molecules whose long axes are oriented in the y-axis direction are arranged in a convex arc shape. Therefore, the light passing through the optical element 10 diffuses in the y-axis direction in each of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4. Figure 6B In the timing chart shown, a linear light distribution extending in the y-axis direction can be obtained.

[0091] exist Figure 6CIn the case of the timing diagram shown, a lateral electric field is generated between two adjacent transparent electrodes 120 extending in the y-axis direction and between two adjacent transparent electrodes 120 extending in the x-axis direction. In this case, not only the liquid crystal molecules whose long axes are oriented in the x-axis direction on one substrate 110 side of the liquid crystal unit 100, but also the liquid crystal molecules whose long axes are oriented in the y-axis direction on the other substrate 110 side of the liquid crystal unit 100 are arranged in a convex arc shape. Therefore, the light passing through the optical element 10 diffuses in the x-axis direction and the y-axis direction in each of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4. Therefore, in Figure 6C In the timing diagram shown, when α=β, a circular light distribution can be obtained. When α<β, an elliptical light distribution with a major axis in the x-axis direction can be obtained. When β>α, an elliptical light distribution with a major axis in the y-axis direction can be obtained.

[0092] [5-2. Grayscale control of light distribution angle]

[0093] If the magnitude of the voltage applied to the transparent electrode 120 is changed, the degree of diffusion of light in the liquid crystal unit 100 can be changed. Therefore, by controlling the magnitude of the voltage applied to the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4, the grayscale of the light distribution angle of the light passing through the optical element 10 can be controlled. Fig. 7A as well as Figure 7B , the definition of the light distribution angle is explained.

[0094] Fig. 7A as well as Figure 7B Schematic diagram for explaining the definition of the light distribution angle and the half-width at half maximum in the lighting system 1 according to one embodiment of the present invention. More specifically, Figure 7B It means when viewed from the y-axis direction Fig. 7A In the case of a state, a graph is drawn in which the horizontal axis is set to the polar angle in the x-axis direction, the vertical axis is set to the illuminance of the surface S illuminated by the lighting system 1, and the illuminance changes with respect to the polar angle when the light source 20 is set at a polar angle of 0°.

[0095] The light emitted from the light source 20 is controlled by the optical element 10 to distribute the light, and the light having a predetermined distribution shape is projected onto the projection surface. The illuminance of the light on the projection surface is the largest at the center (directly below the light source 20), and decreases as it moves away from the center. The 1 / 2 illuminance angle is essentially defined as the angle between the line in the vertical direction of the light source 20 and the line connecting the point where the illuminance directly below the light source 20 is 50% of the illuminance directly below the light source 20, but Figure 7BIn the figure, it is the polar angle at which the illumination is 50% in the illumination diagram when the illumination directly below the light source 20 is set to 100%. In this specification, the light distribution angle is equal to the 1 / 2 illumination angle, and is sometimes referred to as the half-width at half maximum (Half Width at Half Maximum: HWHM). That is, the light distribution angle can be expressed as the half-width at half maximum θ°. Therefore, in the following, for convenience, the half-width at half maximum is sometimes used as an explanation of the light distribution angle. In addition, twice the half-width at half maximum is the full width at half maximum (Full Width at Half Maximum: FWHM).

[0096] Figure 8 : is a graph showing the correlation between the voltage applied to the transparent electrode 120 of the optical element 10 and the half width at half maximum in the lighting system 1 according to one embodiment of the present invention. Figure 8 The data measured in the manufactured lighting system 1 are shown in FIG. Figure 8 The black dots in the figure) and their approximate curves.

[0097] like Figure 8 As shown, the half-width at half maximum of the voltage applied to the transparent electrode 120 represents a complex curve. For example, Figure 8 The function f(x) of the approximate curve shown can be expressed by equation (1) as the sum of two sigmoid functions.

[0098]

[0099] In the formula (1), k1 and k2 are proportionality constants, and z is a predetermined coefficient.

[0100] In addition, formula (1) is an example, and the function f(x) for calculating the half-width at half maximum for the voltage x is not limited to formula (1). In particular, the constants of formula (1) can be changed according to the number of liquid crystal cells 100 included in the optical element 10 and the type of the light source 20. The function f(x) can be calculated based on the measured data as long as it is a function that represents the correlation between the voltage x applied to the transparent electrode 120 of the liquid crystal cell 100 and the half-width at half maximum.

[0101] In the grayscale control of the light distribution of the lighting system 1, the light distribution angle can be changed by user operation. Here, since the relationship between the light distribution angle and the voltage is as complicated as the above-mentioned function f(x), by simply equally distributing the voltage x to the grayscale level operated by the user, there are cases where the change in the light distribution angle is large or small depending on the grayscale level, and there are cases where it is inconsistent with the user's operation feeling. In addition, it is sometimes difficult to make a small adjustment of the light distribution angle according to the grayscale level. For this reason, in the lighting system 1, a function g(p) representing the correlation between the grayscale level p and the light distribution angle shown in formula (2) is introduced.

[0102]

[0103] In formula (2), a and c are arbitrary constants, and b is a weighting coefficient. Here, the constants a and c are a>0 and c>0, and the weighting coefficient b is b≥1. In the function g(p), the light distribution angle increases as the grayscale level p increases. The number of grayscale levels p, i.e., the number of grayscales, is, for example, 256 (grayscale levels 0 to 255), but is not limited to this. In addition, p max is the maximum number of grayscales set. When the grayscale level is 0~255, p max is 255. According to the grayscale number, p max For example, when the number of grayscales is 16, 32, and 64 (all of which include 0 as the smallest grayscale), p max 15, 31, and 63 are used respectively. In addition, when the minimum grayscale does not include 0, p max Depending on the respective grayscale numbers, of course, they are 16, 32, 64 or 256, etc.

[0104] When the orientation state is expressed as a percentage such as n%, g(n) can also be defined as in formula (3).

[0105]

[0106] As mentioned above, the luminous intensity distribution angle is the same as the half-width at half maximum. In order to unify the names, the term half-width at half maximum is used for explanation. That is, f(x) and g(p) are both formulas for calculating the half-width at half maximum. Therefore, if f(x) = g(p), the voltage x for the gray level p can be calculated. In addition, the constant c corresponds to the half-width at half maximum when the gray level is 0. That is, the constant c can be calculated based on the half-width at half maximum when the voltage x = 0V. In addition, if the maximum gray level p is used max And the maximum voltage x max Half-width at half maximum A max , it can be expressed as A max =a·(p max / 255) b +c. Therefore, if the weighting coefficient b is determined, the constant a can be calculated.

[0107] As can be seen from formula (2), the weighting coefficient b is a value that determines the ratio of the change in half-width at half maximum to the change in gray level p. If the weighting coefficient b becomes larger, the change in the light distribution angle at the lower gray level p becomes smaller, and the change in the light distribution angle at the upper gray level p becomes larger. In other words, when the weighting coefficient b becomes larger, the number of gray levels on the low gray level side increases. Therefore, in this case, fine adjustment of the smaller half-width at half maximum becomes easy. In the lighting system 1, when the lighting mode is an angle lighting mode, it is mostly used with a smaller light distribution angle rather than a larger light distribution angle. In this case, it is preferred that the weighting coefficient b is larger. In this way, in the lighting system 1, the weighting coefficient b can be changed according to the purpose (lighting mode) used. Therefore, the storage unit 340 includes a plurality of weighting coefficients 341 corresponding to a plurality of lighting modes. In addition, the weighting coefficient b is not limited to a natural number.

[0108] Fig. 9 This is a flowchart for explaining the grayscale control process in the lighting system 1 according to one embodiment of the present invention. Fig. 9 The flowchart shown includes steps S110 to S150 , but the grayscale control process may also include other steps.

[0109] In step S110, the communication unit 310 receives the lighting pattern information transmitted from the information communication terminal 40. The lighting pattern information is one of the user input information, and is generated when the user operates the input unit 430 of the information communication terminal 40.

[0110] In step S120 , the optical element control unit 330 determines the weighting coefficient b based on the illumination mode information. Specifically, the optical element control unit 330 determines the weighting coefficient b corresponding to the illumination mode information from among the plurality of weighting coefficients 341 stored in the storage unit 340 .

[0111] In step S130, the communication unit 310 receives the grayscale information transmitted from the information communication terminal 40. The grayscale information is one of the user input information, and is generated when the user operates the input unit 430 of the information communication terminal 40.

[0112] In step S140, the optical element control unit 330 calculates the voltage to be applied to the transparent electrode 120 based on the grayscale information. Specifically, the optical element control unit 330 determines the grayscale level p based on the grayscale information, and calculates the voltage x based on the determined grayscale level p and the relational expression f(x)=g(p).

[0113] In step S150 , the optical element control unit 330 inputs a signal including the calculated voltage x to the transparent electrode 120 of the liquid crystal cell 100 .

[0114] As described above, in the lighting system 1, the optical element control unit 330 can calculate the voltage input to the first to fourth transparent electrodes 120-1 to 120-4 of each of the first to fourth liquid crystal cells 100-1 to 100-4 based on the grayscale information and the weighting coefficient b.

[0115] [6. Difference in grayscale caused by difference in weighting coefficient b]

[0116] [6-1. Case where weighting coefficient b=1]

[0117] Fig. 10A : is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=1 in the lighting system 1 according to one embodiment of the present invention. Fig. 10B This is a graph showing the correlation between the grayscale and the voltage applied to the transparent electrode 120 when the weighting coefficient b=1 in the lighting system 1 according to the embodiment of the present invention.

[0118] exist Fig. 10A The graph of g(p)=ap+c with weighting factor b=1 in equation (2) is shown in FIG. Fig. 10A As shown in the graph, the change in half-width at half maximum is constant relative to the change in grayscale level p. However, the change in the area of ​​the light distribution shape in the projection surface is not constant. For example, when changing from grayscale level 15 to grayscale level 30, the change in half-width at half-maximum is 1.65°, and the area change rate of the light distribution shape is 1.95%. On the other hand, when changing from grayscale level 240 to grayscale level 255, the change in half-width at half-maximum is 1.65°, but the area change rate of the light distribution shape is 1.14%. That is, in the comparison based on the area change rate of the light distribution shape, the change at the lower grayscale level is larger than that at the upper grayscale level. This means that the increase in area in the lower grayscale level is greater than the increase in area in the upper grayscale level. Therefore, the user is more likely to feel the diffusion of lighting in the grayscale level that is lower than the upper grayscale level.

[0119] exist Fig. 10B In the figure, a relational expression indicating the correlation between the grayscale level p and the voltage x calculated as f(x)=g(p) when the weighting coefficient b=1 is shown as a graph. In the lighting system 1, the optical element control unit 330 can be based on Fig. 10B The relationship shown converts the grayscale level p into voltage x.

[0120] [6-2. Case where weighting coefficient b=2]

[0121] Fig.11A: is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=2 in the lighting system 1 according to one embodiment of the present invention. Fig. 11B This is a graph showing the correlation between the grayscale and the voltage applied to the transparent electrode 120 when the weighting coefficient b=2 in the lighting system 1 according to the embodiment of the present invention.

[0122] exist Fig.11A It is shown in the equation (2) that g(p)=ap with weighting factor b=2 2 +c chart. Fig.11A As shown in the graph, the change in the half-width at half maximum is not constant relative to the change in the grayscale level p. The change in the half-width at half maximum changes further at grayscale levels higher than the lower grayscale levels. However, the change in the area of ​​the light distribution shape in the projection surface is not as large as the change in the half-width at half maximum. For example, when changing from grayscale level 15 to grayscale level 30, the increase in the half-width at half maximum is 0.292°, and the area increase rate of the light distribution shape is 1.23%. On the other hand, when changing from grayscale level 240 to grayscale level 255, the increase in the half-width at half maximum is 3.106°, and the area increase rate of the light distribution shape is 1.30%. The area increase rate of the light distribution shape is the same at the lower grayscale level and the upper grayscale level. Therefore, the user can feel the same degree of expansion of lighting at the lower grayscale level and the upper grayscale level.

[0123] Fig. 11B The graph showing the relational expression of the correlation between the grayscale level p and the voltage x calculated as f(x)=g(x) when the weighting coefficient b=2 is shown. In the lighting system 1, the optical element control unit 330 can be based on Fig. 11B The relationship shown converts the grayscale level p into voltage x.

[0124] [6-3. Case where weighting coefficient b=3]

[0125] Fig. 12A : is a graph showing the correlation between grayscale and half width at half maximum when the weighting coefficient b=3 in the lighting system 1 according to one embodiment of the present invention. Fig. 12B This is a graph showing the correlation between the grayscale and the voltage applied to the transparent electrode 120 when the weighting coefficient b=3 in the lighting system 1 according to the embodiment of the present invention.

[0126] exist Fig. 12A It is shown in the equation (2) that g(p)=ap with weighting factor b=3 3 +c chart. Fig. 12AAs can be seen from the graph shown, the increase in half-width at half maximum is not constant with respect to the increase in gray level p. Compared with the case of b=2, in the case of b=3, the change in half-width at half maximum in the lower gray level is smaller, and the change in half-width at half maximum in the upper gray level is larger. Therefore, the user can adjust the slight expansion of the lighting in the lower gray level.

[0127] Fig. 12B The graph shows a relational expression representing the correlation between the grayscale level p and the voltage x calculated as f(x)=g(p) when the weighting coefficient b=3. Fig. 12B The relationship shown converts the grayscale level p into voltage x.

[0128] In the above, the correlation between the gray level p and the half-width at half maximum is described when the weight coefficient b is 1, 2, and 3. However, if the weight coefficient b is increased, the number of gray levels in the case of a smaller half-width at half maximum can be increased. For example, when the lighting mode is an angle lighting mode such as a spotlight, sometimes a larger half-width at half maximum is not required but a fine adjustment at a smaller half-width at half maximum is required. In this case, for example, by setting the weight coefficient b to 3, the gray level p is converted into a voltage x, the number of gray levels at a smaller half-width at half maximum increases, and the gray level of the light distribution can be finely adjusted.

[0129] As described above, in the lighting system 1 according to the present embodiment, formula (2) is introduced, and the optical element control unit 330 calculates the voltage x applied to the transparent electrode 120, thereby being able to control the grayscale based on the calculated voltage x so that the light distribution angle increases monotonically (or decreases monotonically). That is, the lighting system 1 can easily perform grayscale control of light distribution. In addition, formula (2) includes a weighting coefficient b, and by changing the weighting coefficient b, it is possible to perform grayscale control of light distribution that matches the purpose (lighting mode) used by the user. Therefore, in the lighting system 1, the grayscale of light distribution can be controlled in accordance with the lighting mode.

[0130] <Second Embodiment>

[0131] Reference Fig.13 , a lighting system 1A according to an embodiment of the present invention will be described. Hereinafter, when the configuration of the lighting system 1A is the same as the configuration of the lighting system 1, the description of the configuration of the lighting system 1A may be omitted.

[0132] Fig.131 is a block diagram for explaining a lighting system 1A according to an embodiment of the present invention. The control device 30 includes a communication unit 310, a light source control unit 320, an optical element control unit 330A, and a storage unit 340. The storage unit 340 stores a plurality of weighting coefficients 341 corresponding to a plurality of lighting modes. In addition, the storage unit 340 also stores a plurality of lookup tables (LUTs) 342A corresponding to the plurality of weighting coefficients 341.

[0133] In the lookup table 342A, the voltage x of the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4 at each gray level p calculated according to equations (1) and (2) is allocated. That is, in the lookup table 342A, the gray level of the light distribution angle, the weighting coefficient, and the voltage x of the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4 are associated.

[0134] The optical element control unit 330A can generate a signal for controlling the optical element 10 and input the generated signal to the first liquid crystal unit 100 - 1 to the fourth liquid crystal unit 100 - 4 , thereby controlling the shape and grayscale of light distribution.

[0135] Specifically, the optical element control section 330A determines the weight coefficient b corresponding to the illumination mode information from the plurality of weight coefficients 341 stored in the storage section 340 based on the illumination mode information transmitted from the information communication terminal 40. The optical element control section 330A determines the grayscale level based on the grayscale information transmitted from the information communication terminal 40. The optical element control section 330A obtains a lookup table corresponding to the weight coefficient b from the plurality of lookup tables 342A stored in the storage section 340. The optical element control section 330A obtains the voltage of the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of each of the first liquid crystal cell 100-1 to the fourth liquid crystal cell 100-4 corresponding to the grayscale level based on the obtained lookup table. The optical element control section 330A inputs a signal including the obtained voltage to the first transparent electrode 120-1 to the fourth transparent electrode 120-4 of each of the first liquid crystal cell 100-1 to the fourth liquid crystal cell 100-4. Thus, the light emitted from the light source 20 is controlled to have a light distribution having a grayscale desired by the user.

[0136] As described above, in the lighting system 1A involved in this embodiment, by storing a plurality of lookup tables 342A and obtaining a predetermined lookup table by the optical element control unit 330A, it is possible to control the grayscale based on the obtained lookup table so as to increase (or decrease) the light distribution angle. That is, the lighting system 1 can easily perform grayscale control of light distribution. In addition, the formula (2) includes a weighting coefficient b, and by changing the weighting coefficient b, it is possible to perform grayscale control of light distribution that matches the purpose (lighting mode) used by the user. Therefore, in the lighting system 1A, it is possible to control the lighting mode in accordance with the grayscale of light distribution.

[0137] <Third Embodiment>

[0138] Reference Fig.14 , a lighting system 1B according to an embodiment of the present invention will be described. Hereinafter, when the configuration of the lighting system 1B is the same as that of the lighting system 1, the description of the configuration of the lighting system 1B may be omitted.

[0139] Fig.14 1 is a block diagram illustrating a lighting system 1B according to an embodiment of the present invention. The control device 30 includes a communication unit 310, a light source control unit 320, and an optical element control unit 330B. In addition, the information communication terminal 40 includes a communication unit 410, a display unit 420, an input unit 430, a calculation unit 440B, and a storage unit 450B. The storage unit 450B stores weighting coefficients 451B corresponding to a plurality of lighting modes.

[0140] The operation unit 440B is, for example, a computer. The operation unit 440B can generate grayscale data required for controlling the optical element 10. Specifically, the operation unit 440B determines the weighting coefficient b corresponding to the illumination mode information from the plurality of weighting coefficients 451B stored in the storage unit 450B based on the illumination mode information generated by the input unit 430. The operation unit 440B determines the grayscale level based on the grayscale information generated by the input unit 430. The operation unit 440B calculates the voltage applied to the transparent electrode 120 based on the determined grayscale level and the relationship of f(x)=g(x). In addition, the voltage is calculated for all the first transparent electrodes 120-1 to the fourth transparent electrodes 120-4 of the first liquid crystal unit 100-1 to the fourth liquid crystal unit 100-4. The grayscale data including the calculated voltage is sent to the control device 30 via the communication unit 410.

[0141] The optical element control unit 330B can generate a signal for controlling the optical element 10 based on the transmitted grayscale data, and input the generated signal to the first liquid crystal unit 100 - 1 to the fourth liquid crystal unit 100 - 4 , thereby controlling the shape and grayscale of light distribution.

[0142] As described above, in the lighting system 1B according to the present embodiment, the program is installed in the user's information communication terminal 40, and the calculation unit 440B uses the formula (2) to calculate the voltage x applied to the transparent electrode 120. The calculated voltage x is sent to the control device 30, and the optical element control unit 330B can control the grayscale based on the sent voltage x so that the light distribution angle increases monotonically (or decreases monotonically). That is, the lighting system 1A can easily perform grayscale control of light distribution.

[0143] Within the scope of the concept of the present invention, as long as a person skilled in the art can think of various variations and modifications, these variations and modifications are also understood to belong to the scope of the present invention. For example, for each of the above-mentioned embodiments, a person skilled in the art appropriately adds, deletes or changes the design of the constituent elements, or adds, omits or changes the conditions of the processes, as long as they have the gist of the present invention, they are also included in the scope of the present invention.

[0144] In addition, other effects brought about by each embodiment that are clearly known from the description of this specification or that can be appropriately imagined by a person skilled in the art are naturally understood to be effects brought about by the present invention.

[0145] Description of Reference Numerals

[0146] 1, 1A, 1B: lighting system; 10: optical element; 20: light source; 30: control device; 40: information communication terminal; 100: liquid crystal unit; 110: substrate; 120: transparent electrode; 121: connecting pad; 122: terminal; 130: first orientation film; 140: sealing material; 150: liquid crystal layer; 160: optical elastic resin layer; 170: flexible printed substrate (FPCs); 310: communication unit; 320: light source control unit; 330, 330A: optical element control unit; 340: storage unit; 342A: lookup table; 410: communication unit; 420: display unit; 430: input unit; 440B: operation unit; 450B: storage unit; 1000-1: first light; 1000-2: second light.

Claims

1. A lighting system, comprising: light source; a liquid crystal unit that changes the light distribution angle of the light emitted from the light source; as well as A control device controls the grayscale of the light distribution angle, The liquid crystal unit comprises: A first substrate, alternately provided with first transparent electrodes and second transparent electrodes extending in a first direction respectively; A second substrate having third transparent electrodes and fourth transparent electrodes alternately arranged thereon and extending in a second direction intersecting the first direction, respectively; and A liquid crystal layer between the first substrate and the second substrate, The control device comprises: A communication unit, receiving the grayscale information of the light distribution angle from an information communication terminal; a storage unit storing a weighting coefficient associating the amount of change in the light distribution angle with a change in the grayscale of the light distribution angle; and The control unit calculates a first voltage input to the first transparent electrode, a second voltage input to the second transparent electrode, a third voltage input to the third transparent electrode, and a fourth voltage input to the fourth transparent electrode based on the grayscale information and the weighting coefficient.

2. The lighting system according to claim 1, wherein: The storage unit includes a plurality of the weighting coefficients corresponding to a plurality of lighting modes.

3. The lighting system according to claim 1, wherein: The storage unit includes a lookup table in which the grayscale level of the light distribution angle, the weighting coefficient, the first voltage, the second voltage, the third voltage, and the fourth voltage are associated with each other.

4. The lighting system according to claim 3, wherein: The storage unit includes a plurality of the lookup tables corresponding to a plurality of the weighting coefficients.

5. The lighting system according to claim 3, wherein: In the lookup table, a first function f(x) representing the correlation between the voltage x and the light distribution angle f calculated based on the measurement data and a second function g(p)=a(p / p) for converting the grayscale level p into the light distribution angle g are used. max ) b +c, based on the fact that the light distribution angle g determined according to the second function g(p) is consistent with the light distribution angle f determined according to the first function f(x), that is, g(x)=f(x), the voltage x corresponding to the gray level p is associated, wherein a and c are arbitrary constants, b is the weighting coefficient, and p max It is the maximum value among the set grayscale levels.

6. The lighting system according to claim 5, wherein: The weighting coefficient b is greater than or equal to 1.

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