Lighting system

Abstract

Provided is a lighting system capable of implementing dynamic light distribution control synchronized with music reproduction. The present invention is provided with: a lighting device (1) that can control the light distribution state of light emitted from a light source; and a control device 300 that reproduces music data, and that, so as to dynamically control the light distribution state of the lighting device (1), transmits, to the lighting device (1), light distribution data synchronized with the time series variation in the music data. The control device 300 starts to reproduce the music data at a second time (RT3+DTPS) that is obtained by adding, to a first time (RT3) acquired by the lighting device (1), the transmission delay time (DTPS) of transmission from the lighting device (1) to the control device 300. The lighting device (1) starts to control the light distribution state at a third time (RT3+DTPS) that is obtained by adding the transmission delay time (DTPS) to the first time (RT3).

Description

lighting system

[0001] The present invention relates to a lighting system.

[0002] Conventionally, there have been lighting fixtures that combine a light source such as an LED with a thin lens engraved with a prism pattern, and change the spread of light (hereinafter also referred to as "light distribution") by changing the distance between the light source and the thin lens. For example, a lighting fixture has been disclosed in which the front of a transparent light bulb is covered with a liquid crystal dimming element and the transmittance of the liquid crystal layer is changed to switch between direct light and scattered light (see, for example, Patent Document 1). Also, a lighting control device has been disclosed that changes the brightness of lighting over time to create a flickering light like a candle flame (see, for example, Patent Document 2).

[0003] Japanese Patent Laid-Open No. 2-65001 Japanese Patent Laid-Open No. 2009-004329

[0004] 1 / f fluctuations, which are a harmonious blend of regularity and irregularity, are a phenomenon commonly seen in nature, such as candle flames and the murmuring of a river, and can provide psychological comfort. The psychological effects of such fluctuations are also observed in audio signals, such as music. For example, it is desirable to be able to create fluctuations in audio signals in lighting devices with controllable light distribution. In such systems that create fluctuations in audio signals, there is a possibility that synchronization errors may occur between the device that plays the music and the lighting device that controls the light distribution.

[0005] An object of the present invention is to provide a lighting system that can realize dynamic light distribution control synchronized with music playback.

[0006] A lighting system according to one aspect of the present disclosure includes a lighting device capable of controlling the light distribution state of light emitted from a light source, and a control device that plays music data and transmits light distribution data synchronized with time-series changes in the music data to the lighting device to dynamically control the light distribution state of the lighting device, wherein the control device starts playing the music data at a second time obtained by adding a transmission delay time from the lighting device to the lighting device to a first time acquired by the lighting device, and the lighting device starts controlling the light distribution state at a third time obtained by adding the transmission delay time to the first time.

[0007] A lighting system according to one aspect of the present disclosure includes a lighting device capable of controlling the light distribution state of light emitted from a light source, and a control device that plays music data and transmits light distribution data synchronized with time-series changes in the music data to the lighting device, thereby dynamically controlling the light distribution state of the lighting device, wherein the control device starts playing the music data at a second time obtained by adding a transmission delay time from the control device to the lighting device to a first time acquired by the lighting device, and the lighting device starts controlling the light distribution state at a third time obtained by adding the transmission delay time to the first time.

[0008] FIG. 1A is a side view showing an example of an illumination device according to an embodiment. FIG. 1B is a perspective view showing an example of an optical element according to an embodiment. FIG. 2 is a schematic plan view of a first substrate as viewed from the Dz direction. FIG. 3 is a schematic plan view of a second substrate as viewed from the Dz direction. FIG. 4 is a perspective view of a liquid crystal cell in which a first substrate and a second substrate are stacked in the Dz direction. FIG. 5 is a cross-sectional view taken along the line AA′ shown in FIG. 4. FIG. 6A is a diagram showing the alignment direction of an alignment film on a first substrate. FIG. 6B is a diagram showing the alignment direction of an alignment film on a second substrate. FIG. 7 is a diagram showing a layered structure of an optical element according to an embodiment. FIG. 8A is a conceptual diagram for explaining a change in the shape of light caused by an optical element according to an embodiment. FIG. 8B is a conceptual diagram for explaining a change in the shape of light caused by an optical element according to an embodiment. FIG. 8C is a conceptual diagram for explaining a change in the shape of light caused by an optical element according to an embodiment. FIG. 8D is a conceptual diagram for explaining a change in the shape of light caused by an optical element according to an embodiment. FIG. 9 is a conceptual diagram for conceptually explaining light distribution control by an illumination device according to an embodiment. FIG. 10 is a diagram showing a schematic configuration of an illumination system according to an embodiment. FIG. 11 is a block diagram showing an example of a lighting device according to an embodiment. FIG. 12 is a block diagram showing an example of a control device according to an embodiment. FIG. 13 is a conceptual diagram showing an example of music data. FIG. 14 is a flowchart showing an example of light distribution data generation processing. FIG. 15 is a flowchart showing an example of light distribution control processing according to the first embodiment. FIG. 16 is a sub-flowchart showing an example of initial synchronization processing in the control device for light distribution control processing according to the first embodiment. FIG. 17 is a sub-flowchart showing an example of initial synchronization processing in the lighting device for light distribution control processing according to the first embodiment. FIG. 18 is a sequence diagram showing an example of initial synchronization processing in the light distribution control processing according to the first embodiment. FIG. 19 is a sub-flowchart showing an example of synchronization control processing in the control device for light distribution control processing according to the first embodiment. FIG. 20 is a sub-flowchart showing an example of synchronization control processing in the lighting device for light distribution control processing according to the first embodiment. FIG. 21 is a sequence diagram showing an example of synchronization control processing in the light distribution control processing according to the first embodiment. FIG. 22 is a sub-flowchart showing an example of re-synchronization processing in the control device for light distribution control processing according to the first embodiment.FIG. 23 is a sub-flowchart showing an example of resynchronization processing in a lighting device in light distribution control processing according to embodiment 1. FIG. 24 is a sequence diagram showing an example of resynchronization processing in light distribution control processing according to embodiment 1. FIG. 25A is a conceptual diagram showing an example of operations in synchronization control processing according to embodiment 1. FIG. 25B is a conceptual diagram showing an example of operations in synchronization control processing according to embodiment 1. FIG. 26 is a flowchart showing an example of light distribution control processing according to a modified example of embodiment 1. FIG. 27 is a sub-flowchart showing an example of initial synchronization processing in a control device in light distribution control processing according to a modified example of embodiment 1. FIG. 28 is a sub-flowchart showing an example of initial synchronization processing in a lighting device in light distribution control processing according to a modified example of embodiment 1. FIG. 29 is a sequence diagram showing an example of initial synchronization processing in light distribution control processing according to a modified example of embodiment 1. FIG. 30 is a sub-flowchart showing an example of synchronization control processing in a control device in light distribution control processing according to a modified example of embodiment 1. FIG. 31 is a sub-flowchart showing an example of synchronization control processing in a lighting device in light distribution control processing according to a modified example of embodiment 1. FIG. 32 is a sequence diagram showing an example of synchronization control processing of light distribution control processing according to a modified example of the first embodiment. FIG. 33 is a sub-flowchart showing an example of resynchronization processing in a control device of light distribution control processing according to a modified example of the first embodiment. FIG. 34 is a sub-flowchart showing an example of resynchronization processing in a lighting device of light distribution control processing according to a modified example of the first embodiment. FIG. 35 is a sequence diagram showing an example of resynchronization processing in light distribution control processing according to a modified example of the first embodiment. FIG. 36 is a flowchart showing an example of light distribution control processing according to the second embodiment. FIG. 37 is a sub-flowchart showing an example of resynchronization processing in a control device of light distribution control processing according to the second embodiment. FIG. 38 is a sub-flowchart showing an example of resynchronization processing in a lighting device of light distribution control processing according to the second embodiment. FIG. 39 is a sequence diagram showing an example of resynchronization processing in light distribution control processing according to the second embodiment. FIG. 40 is a flowchart showing an example of light distribution control processing according to a modified example of the second embodiment. FIG. 41 is a sub-flowchart showing an example of resynchronization processing in a control device of light distribution control processing according to a modified example of the second embodiment.FIG. 42 is a sub-flowchart showing an example of resynchronization processing in a lighting device in light distribution control processing according to a modification of the second embodiment. FIG. 43 is a sequence diagram showing an example of resynchronization processing in light distribution control processing according to a modification of the second embodiment. FIG. 44 is a flowchart showing an example of light distribution control processing according to the third embodiment. FIG. 45 is a sub-flowchart showing an example of processing in a control device in light distribution control processing according to the third embodiment. FIG. 46 is a sub-flowchart showing an example of processing in a lighting device in light distribution control processing according to the third embodiment. FIG. 47 is a sequence diagram showing an example of light distribution control processing according to the third embodiment. FIG. 48 is a flowchart showing an example of light distribution control processing according to a modification of the third embodiment. FIG. 49 is a sub-flowchart showing an example of processing in a control device in light distribution control processing according to a modification of the third embodiment. FIG. 50 is a sub-flowchart showing an example of processing in a lighting device in light distribution control processing according to a modification of the third embodiment. FIG. 51 is a sequence diagram showing an example of light distribution control processing according to a modification of the third embodiment. FIG. 52 is a diagram showing a schematic configuration of a lighting system according to a modification of an embodiment. FIG. 53 is a block diagram showing an example of a control device according to a modification of an embodiment. FIG. 54 is a block diagram illustrating an example of a speaker device according to a modified example of the embodiment.

[0009] Modes for carrying out the invention (embodiments) will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. The disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the invention are naturally included within the scope of the present invention. Furthermore, for clarity of explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present invention. Furthermore, in this specification and each figure, elements similar to those described above with reference to the previous figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0010] FIG. 1A is a side view showing an example of an illumination device according to an embodiment. FIG. 1B is a perspective view showing an example of an optical element according to an embodiment. As shown in FIG. 1A, the illumination device 1 includes a light source 4, a reflector 4a, and an optical element 100. As shown in FIG. 1B, the optical element 100 includes a first liquid crystal cell 2_1, a second liquid crystal cell 2_2, a third liquid crystal cell 2_3, and a fourth liquid crystal cell 2_4. The light source 4 is formed of, for example, a light-emitting diode (LED). The reflector 4a is a component that collects light from the light source 4 onto the optical element 100.

[0011] In FIG. 1B , the Dz direction indicates the emission direction of light from the light source 4 and the reflector 4 a. The optical element 100 is configured by stacking a first liquid crystal cell 2_1, a second liquid crystal cell 2_2, a third liquid crystal cell 2_3, and a fourth liquid crystal cell 2_4 in the Dz direction. In the present disclosure, the optical element 100 is configured by stacking the first liquid crystal cell 2_1, the second liquid crystal cell 2_2, the third liquid crystal cell 2_3, and the fourth liquid crystal cell 2_4 in this order from the light source 4 side (the lower side of FIG. 1B ). In FIG. 1B , one direction of a plane parallel to the stacking plane of the first liquid crystal cell 2_1, the second liquid crystal cell 2_2, the third liquid crystal cell 2_3, and the fourth liquid crystal cell 2_4, which is perpendicular to the Dz direction, is defined as the Dx direction (first direction), and a direction perpendicular to both the Dx direction and the Dz direction is defined as the Dy direction (second direction).

[0012] The first liquid crystal cell 2_1, the second liquid crystal cell 2_2, the third liquid crystal cell 2_3, and the fourth liquid crystal cell 2_4 each have the same configuration. In the present disclosure, the first liquid crystal cell 2_1 and the fourth liquid crystal cell 2_4 are liquid crystal cells for p-wave polarization. Furthermore, the second liquid crystal cell 2_2 and the third liquid crystal cell 2_3 are liquid crystal cells for s-wave polarization. Hereinafter, the first liquid crystal cell 2_1, the second liquid crystal cell 2_2, the third liquid crystal cell 2_3, and the fourth liquid crystal cell 2_4 will also be collectively referred to as "liquid crystal cells 2."

[0013] The liquid crystal cell 2 includes a first substrate 5 and a second substrate 6. FIG. 2 is a schematic plan view of the first substrate as viewed from the Dz direction. FIG. 3 is a schematic plan view of the second substrate as viewed from the Dz direction. In FIG. 3, the drive electrodes are visible through the substrates, but the drive electrodes and wiring are shown with solid lines for clarity. FIG. 4 is a perspective view of a liquid crystal cell in which the first and second substrates are stacked in the Dz direction. In FIG. 4, the drive electrodes and wiring on the second substrate side are shown with solid lines, and the drive electrodes and wiring on the first substrate side are shown with dotted lines for clarity. FIG. 5 is a cross-sectional view taken along line A-A' in FIG. 4. Note that FIGS. 2, 3, 4, and 5 illustrate a third liquid crystal cell 2_3 and a fourth liquid crystal cell 2_4 in which the drive electrodes 10a and 10b of the first substrate 5 extend in the Dx direction and the drive electrodes 13a and 13b of the second substrate 6 extend in the Dy direction.

[0014] As shown in FIG. 5, the liquid crystal cell 2 includes a liquid crystal layer 8 between a first substrate 5 and a second substrate 6, the periphery of which is sealed with a sealing material 7.

[0015] The liquid crystal layer 8 modulates light passing through the liquid crystal layer 8 according to the state of the electric field. Positive nematic liquid crystal is used as the liquid crystal molecules, but other liquid crystals having a similar effect may also be used.

[0016] As shown in FIG. 2 , the liquid crystal layer 8 side of the base material 9 of the first substrate 5 is provided with a plurality of drive electrodes 10a, 10b, a plurality of metal wirings 11a, 11b that supply drive voltages to the drive electrodes 10a, 10b, and a plurality of metal wirings 11c, 11d that supply drive voltages to a plurality of drive electrodes 13a, 13b (see FIG. 3 ) provided on the second substrate 6, which will be described later. The metal wirings 11a, 11b, 11c, and 11d are provided in a wiring layer on the first substrate 5. The metal wirings 11a, 11b, 11c, and 11d are provided at intervals in the wiring layer on the first substrate 5. Hereinafter, the plurality of drive electrodes 10a, 10b may be simply referred to as "drive electrodes 10." Furthermore, the plurality of metal wirings 11a, 11b, 11c, and 11d may be referred to as "first metal wirings 11." 2, in the third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4, the drive electrodes 10 on the first substrate 5 extend in the Dx direction. Note that in the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2, the drive electrodes 10 on the first substrate 5 extend in the Dy direction.

[0017] As shown in FIG. 3 , the liquid crystal layer 8 side of the base material 12 of the second substrate 6 shown in FIG. 5 includes multiple drive electrodes 13a and 13b and multiple metal wirings 14a and 14b that supply drive voltages to these drive electrodes 13. The metal wirings 14a and 14b are provided in the wiring layer of the second substrate 6. The metal wirings 14a and 14b are provided at intervals in the wiring layer on the second substrate 6. Hereinafter, the multiple drive electrodes 13a and 13b may be simply referred to as "drive electrodes 13." The multiple metal wirings 14a and 14b may be referred to as "second metal wirings 14." As shown in FIG. 3 , in the third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4, the drive electrodes 13 on the second substrate 6 extend in the Dy direction. Note that, in the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2, the drive electrodes 13 on the second substrate 6 extend in the Dx direction.

[0018] The driving electrodes 10 and 13 are translucent electrodes formed of a translucent conductive material (translucent conductive oxide) such as ITO (indium tin oxide). The first substrate 5 and the second substrate 6 are translucent substrates such as glass or resin. The first metal wiring 11 and the second metal wiring 14 are formed of at least one metal material selected from aluminum (Al), copper (Cu), silver (Ag), molybdenum (Mo), and alloys thereof. The first metal wiring 11 and the second metal wiring 14 may also be formed as a laminated body in which a plurality of layers are stacked using one or more of these metal materials. At least one metal material selected from aluminum (Al), copper (Cu), silver (Ag), molybdenum (Mo), and alloys thereof has lower resistance than a translucent conductive oxide such as ITO.

[0019] The metal wiring 11c of the first substrate 5 and the metal wiring 14a of the second substrate 6 are connected by a conductive portion 15a made of, for example, conductive paste, etc. The metal wiring 11d of the first substrate 5 and the metal wiring 14b of the second substrate 6 are connected by a conductive portion 15b made of, for example, conductive paste, etc.

[0020] Furthermore, connection (Flex-on-Board) terminal portions 16a and 16b to be connected to a flexible printed circuit (FPC) (not shown) are provided in an area on the first substrate 5 that does not overlap with the second substrate 6 in the Dz direction. The connection terminal portions 16a and 16b each include four connection terminals corresponding to the metal wirings 11a, 11b, 11c, and 11d.

[0021] The connection terminals 16a and 16b are provided on the wiring layer of the first substrate 5. A drive voltage is supplied to the liquid crystal cell 2 from the FPC connected to the connection terminal 16a or the connection terminal 16b to be applied to the drive electrodes 10a and 10b on the first substrate 5 and the drive electrodes 13a and 13b on the second substrate 6. Hereinafter, the connection terminals 16a and 16b may be simply referred to as "connection terminals 16."

[0022] As shown in FIG. 4 , the liquid crystal cell 2 has the first substrate 5 and the second substrate 6 overlapping in the Dz direction (light irradiation direction), and the plurality of drive electrodes 10 on the first substrate 5 intersect with the plurality of drive electrodes 13 on the second substrate 6 as viewed from the Dz direction. In the liquid crystal cell 2 configured in this manner, the alignment direction of the liquid crystal molecules 17 in the liquid crystal layer 8 can be controlled by supplying drive voltages to the plurality of drive electrodes 10 on the first substrate 5 and the plurality of drive electrodes 13 on the second substrate 6, respectively. The region in which the alignment direction of the liquid crystal molecules 17 in the liquid crystal layer 8 can be controlled is referred to as the "effective area AA." In the effective area AA, the refractive index distribution of the liquid crystal layer 8 changes, thereby enabling control of the degree of diffusion of light passing through the effective area AA of the liquid crystal cell 2. The region outside the effective area AA, where the liquid crystal layer 8 is sealed with the sealant 7, is referred to as the "peripheral area GA" (see FIG. 5 ).

[0023] 5, in the effective area AA of the first substrate 5, the drive electrode 10 (drive electrode 10a in FIG. 5) is covered with an alignment film 18. In addition, in the effective area AA of the second substrate 6, the drive electrode 13 (drive electrodes 13a and 13b in FIG. 5) is covered with an alignment film 19. The alignment directions of the liquid crystal molecules in the alignment film 18 and the alignment film 19 are different.

[0024] 6A and 6B are diagrams showing the alignment directions of the alignment film on the first and second substrates, respectively.

[0025] As shown in Figures 6A and 6B, the alignment direction of the alignment film 18 on the first substrate 5 and the alignment direction of the alignment film 19 on the second substrate 6 intersect with each other in a plan view. Specifically, as shown by the solid arrow in Figure 6A, the alignment direction of the alignment film 18 on the first substrate 5 is perpendicular to the extension direction of the drive electrodes 10a and 10b shown by the dashed arrow in Figure 6A. Furthermore, as shown by the solid arrow in Figure 6B, the alignment direction of the alignment film 19 on the second substrate 6 is perpendicular to the extension direction of the drive electrodes 13a and 13b shown by the dashed arrow in Figure 6B. In the following description, the extension direction of each of the drive electrodes 10 and 13 and the alignment direction of the alignment films 18 and 19 covering them are described as being perpendicular to each other, but they may also intersect at an angle other than perpendicular, for example, an angle in the range of 85° to 90°. Furthermore, it is preferable that the drive electrodes 10 on the first substrate 5 side and the drive electrodes 13 on the second substrate 6 side are perpendicular to each other, but they may intersect at an angle ranging from 85° to 90°, for example. The alignment direction of the alignment films 18 and 19 is formed by a rubbing treatment or a photo-alignment treatment.

[0026] Here, the mechanism by which the shape of light is changed by each liquid crystal cell 2 (first liquid crystal cell 2_1, second liquid crystal cell 2_2, third liquid crystal cell 2_3, and fourth liquid crystal cell 2_4) will be described. FIG. 7 is a diagram showing the layered structure of the optical element according to the embodiment. FIGS. 8A, 8B, 8C, and 8D are conceptual diagrams for explaining the change in the shape of light by the optical element according to the embodiment. FIGS. 8A, 8B, 8C, and 8D show an example in which a potential difference is generated between each drive electrode of the shaded substrate of each liquid crystal cell 2.

[0027] 7, the optical element 100 is provided on the optical axis of the light source 4, indicated by the dashed line, and as described above, the first liquid crystal cell 2_1, the second liquid crystal cell 2_2, the third liquid crystal cell 2_3, and the fourth liquid crystal cell 2_4 are stacked in this order from the light source 4 side (the lower side in FIG. 7). The third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4 are stacked in a state rotated by 90° with respect to the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2.

[0028] 6A and 6B , in each liquid crystal cell 2, the alignment direction of the alignment film intersects between the first substrate 5 side and the second substrate 6 side. As a result, the orientation of the liquid crystal molecules in the liquid crystal layer 8 gradually changes from the Dx direction to the Dy direction (or from the Dy direction to the Dx direction) as it moves from the first substrate 5 side to the second substrate 6 side, and the polarization component of the transmitted light rotates along this change. That is, in the liquid crystal cell 2, the polarization component that was a p-polarized component on the first substrate 5 side changes to an s-polarized component as it moves toward the second substrate 6 side, and the polarization component that was an s-polarized component on the first substrate 5 side changes to a p-polarized component as it moves toward the second substrate 6 side. This rotation of the polarization component may be referred to as optical rotation.

[0029] 8A shows a state in which no potential is generated between the adjacent electrodes of each liquid crystal cell 2. In this case, only optical rotation occurs in each liquid crystal cell 2, and none of the polarized light components are diffused.

[0030] 8B , for example, by generating a potential difference between the drive electrodes 10 a and 10 b on the first substrate 5 side of the first liquid crystal cell 2_1, the liquid crystal molecules are oriented in an arc shape between the electrodes, thereby forming a refractive index distribution along the Dx direction in the liquid crystal layer 8. When light from the light source 4 passes through in this state, the refractive index distribution acts on the polarized light component parallel to the Dx direction (the p-polarized component in FIG. 8B ), causing the p-polarized light component to diffuse in the Dx direction.

[0031] Furthermore, when a potential difference is also generated between the drive electrodes 13 a and 13 b on the second substrate 6 side of the first liquid crystal cell 2_1, a refractive index distribution in the Dy direction is formed on the second substrate 6 side, which causes the s-polarized component to diffuse in the Dy direction on the second substrate 6 side. That is, the polarized component that changed from a p-polarized component to an s-polarized component while passing through the liquid crystal layer 8 of the first liquid crystal cell 2_1 now diffuses in the Dy direction as well. On the other hand, the s-polarized component when incident on the first liquid crystal cell 2_1 undergoes optical rotation while passing through the liquid crystal layer 8, but becomes a polarized component that intersects with both refractive index distributions, and therefore passes through the first liquid crystal cell 2_1 with only optical rotation without being diffused.

[0032] The s-polarized light component that enters the first liquid crystal cell 2_1 is converted to a p-polarized light component after passing through the first liquid crystal cell 2_1, and the second liquid crystal cell 2_2 acts on the p-polarized light component. That is, as shown in FIGS. 8A and 8B , the first liquid crystal cell 2_1 acts on the p-polarized light component of the light that enters the optical element 100, and the second liquid crystal cell 2_2 acts on the s-polarized light component. The third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4 are rotated 90° relative to the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2, so that the polarization components that act on them are also swapped by 90°. That is, the third liquid crystal cell 2_3 acts on the s-polarized light component that enters the optical element 100, and the fourth liquid crystal cell 2_4 acts on the p-polarized light component that enters the optical element 100.

[0033] 8C , in the optical element, by applying a potential difference between the drive electrodes extending in the Dy direction for each liquid crystal cell 2 (between the drive electrodes 10 a and 10 b on the first substrate 5 for the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2, and between the drive electrodes 13 a and 13 b on the second substrate 6 for the third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4), the p-polarized light component can be acted upon, and the shape of the light can be enlarged mainly in the Dx direction. This effect may be referred to as lateral diffusion.

[0034] 8D , by applying a potential difference between the drive electrodes extending in the Dx direction for each liquid crystal cell 2 (between the drive electrodes 13 a and 13 b on the second substrate 6 in the first liquid crystal cell 2_1 and the second liquid crystal cell 2_2, and between the drive electrodes 10 a and 10 b on the first substrate 5 in the third liquid crystal cell 2_3 and the fourth liquid crystal cell 2_4), the s-polarized light component can be affected, and the shape of the light can be enlarged mainly in the Dy direction. This effect may be called vertical diffusion.

[0035] The degree of light diffusion in each direction depends on the potential difference between adjacent drive electrodes 10a and 10b (or between drive electrodes 13a and 13b). If the potential difference between drive electrodes 10a and 10b (or between drive electrodes 13a and 13b) is set to a predetermined maximum potential difference (e.g., 30 V), the light diffusion in that direction will be maximum (100%). If no potential difference is generated, no light diffusion will occur in that direction (0%). Alternatively, if the potential difference between drive electrodes 10a and 10b (or between drive electrodes 13a and 13b) is set to 50% of the maximum potential difference (e.g., 15 V), the light diffusion in that direction will be 50%. Note that if the relationship between the voltage difference and the light diffusion is not linear, a potential difference other than 15 V can be used.

[0036] The distance (also called the cell gap) between the substrates (between the first substrate 5 and the second substrate 6) of each liquid crystal cell 2 is wide, about 30 μm to 50 μm, which minimizes the influence of the electric field formed on one substrate on the other substrate. Furthermore, the drive voltage that generates a potential difference between adjacent drive electrodes 10 a, 10 b (or drive electrodes 13 a, 13 b) is a so-called AC rectangular wave, which, needless to say, prevents image sticking of the liquid crystal molecules.

[0037] In addition, the orientation direction of each orientation film, the extension direction of the drive electrodes of each substrate, and the angle between them can be changed as appropriate for the entire optical element 100 or for each liquid crystal cell 2 depending on the characteristics of the liquid crystal used and the optical properties desired to be achieved.

[0038] In this embodiment, the optical element 100 is described as having a configuration in which four liquid crystal cells, a first liquid crystal cell 2_1, a second liquid crystal cell 2_2, a third liquid crystal cell 2_3, and a fourth liquid crystal cell 2_4, are stacked together. However, this configuration is not limited to this, and it is also possible to use a configuration in which, for example, two or three liquid crystal cells 2 are stacked together, or a configuration in which five or more liquid crystal cells 2 are stacked together.

[0039] In the present disclosure, in the lighting device 1 configured as described above, the light incident on the optical element from the light source 4 is controlled in two directions, the Dx direction (the direction of horizontal diffusion) and the Dy direction (the direction of vertical diffusion), by controlling the drive voltage of each liquid crystal cell 2. The vertical and horizontal diffusions may be collectively referred to as light diffusion. This changes the shape of the light emitted from the optical element. The light shape refers to the shape of the light that appears on a plane parallel to the exit surface of the optical element, and may also be referred to as the light distribution shape. The control of the degree of light diffusion in the present disclosure will now be described with reference to FIG. 9 .

[0040] 9 is a conceptual diagram for explaining the control of the degree of light diffusion by the lighting device according to the embodiment. Fig. 9 shows the light illumination range on a virtual plane xy perpendicular to the Dz direction. Note that the outline of the actual illumination range may be slightly unclear due to factors such as the distance from the light source 4 and the light diffraction phenomenon.

[0041] As described above, the alignment direction of the liquid crystal molecules 17 in the liquid crystal layer 8 is controlled by supplying a drive voltage to each of the drive electrodes 10, 13 of each liquid crystal cell 2 of the optical element 100 provided on the optical axis of the light source 4. This controls the light distribution shape of the light emitted from the optical element 100.

[0042] Specifically, for example, as described above, the light distribution shape in the Dx direction changes depending on the drive voltage applied to the drive electrodes 10 or 13 extending in the Dy direction in each liquid crystal cell 2. Such diffusion of light in the Dx direction may be referred to as horizontal diffusion. Furthermore, the light distribution shape in the Dy direction changes depending on the drive voltage applied to the drive electrodes 10 or 13 extending in the Dx direction in the first to fourth liquid crystal cells. Such diffusion of light in the Dy direction may be referred to as vertical diffusion.

[0043] In the present disclosure, the minimum diffusivity of the horizontal and vertical diffusion is 0%, and the maximum diffusivity is 100%. More specifically, when the horizontal diffusivity is 0%, the drive electrodes that function to widen the light distribution in the Dx direction (e.g., the drive electrodes 10 extending in the Dy direction on the first substrate 5 of the first liquid crystal cell 2_1) do not affect the refractive index distribution of the liquid crystal layer 8. In this case, there is no potential difference between adjacent drive electrodes 10a, 10b, or no potential is supplied to the electrodes. On the other hand, when the horizontal diffusivity is 100%, the drive electrodes that function to widen the light distribution in the Dx direction (e.g., the drive electrodes 10 extending in the Dy direction on the first substrate 5 of the first liquid crystal cell 2_1) have the maximum effect on the refractive index distribution of the liquid crystal layer 8. In this case, the potential difference between adjacent drive electrodes 10a, 10b is set to the maximum potential difference (e.g., 30 V) in the optical element 100. When the horizontal diffusion degree is greater than 0% but less than 100%, a potential adjusted so that the potential difference between the adjacent drive electrodes 10a and 10b is greater than 0 V but less than the maximum potential difference (e.g., 30 V) is applied to the electrodes. The same applies to the vertical diffusion degree.

[0044] The outline a in Fig. 9 illustrates an illumination range when the horizontal diffusion rate and the vertical diffusion rate are both 100%. The outline b in Fig. 9 illustrates an illumination range when the horizontal diffusion rate is 100% and the vertical diffusion rate is 0%. The outline c in Fig. 9 illustrates an illumination range when the horizontal diffusion rate is 0% and the vertical diffusion rate is 100%. The outline d in Fig. 9 illustrates an illumination range when the horizontal diffusion rate and the vertical diffusion rate are both 0%. That is, the outline d shows the light distribution state when light from the light source 4 is emitted without being controlled by the optical element 100 (i.e., transmitted through the optical element 100 as is).

[0045] In this way, in the lighting device 1 configured as described above, the horizontal and vertical diffusivities of the light emitted from the optical element 100 can be controlled by controlling the drive voltage of each liquid crystal cell 2. This makes it possible to change the light distribution shape of the light emitted from the lighting device 1. Hereinafter, the control that changes the light distribution shape of the light emitted from the lighting device 1 will also be referred to as "light distribution control."

[0046] In this disclosure, an illumination device 1 capable of controlling light distribution in two directions, the Dx direction and the Dy direction, is exemplified, but the controllable parameters of the illumination device 1 are not limited to light distribution (spread of light). For example, the illumination device 1 may be capable of dimming control. In this case, the controllable parameters of the illumination device 1 may include dimming (brightness).

[0047] Hereinafter, a description will be given of the configuration and operation of a lighting device 1 capable of controlling light distribution in two directions, the Dx direction and the Dy direction, in synchronization with music playback, in which the light distribution state in two directions, the Dx direction and the Dy direction, can be dynamically controlled. In this disclosure, "dynamic light distribution control synchronized with music playback" refers to control in which the light distribution shape changes over time in synchronization with changes in the signal level of the music data. Hereinafter, the process of executing this control will also be simply referred to as "light distribution control process."

[0048] Fig. 10 is a diagram showing a schematic configuration of a lighting system 200 according to an embodiment. As shown in Fig. 10, the lighting system 200 according to the embodiment includes a lighting device 1 and a control device 300. The control device 300 is, for example, a portable communication terminal device such as a smartphone or a tablet. In the present disclosure, the lighting device 1 includes the optical element 100 described above, and is configured to be capable of controlling light distribution in two directions, the Dx direction and the Dy direction.

[0049] Data and various command signals are transmitted and received between the control device 300 and the lighting device 1 via a communication means. In the present disclosure, the communication means is, for example, a wireless communication means such as Bluetooth (registered trademark) or Wi-Fi (registered trademark). The control device 300 and the lighting device 1 may communicate wirelessly via a predetermined network such as a mobile communication network. Alternatively, the control device 300 and the lighting device 1 may be connected via a wired connection and communicate via a wired connection.

[0050] In the present disclosure, the control device 300 has a function of generating light distribution data for the lighting device 1 from music data. The control device 300 also has a function of playing back the music data and transmitting the light distribution data generated from the music data to the lighting device 1.

[0051] The configuration required to perform light distribution control in the lighting system 200 according to the embodiment will be described below.

[0052] Fig. 11 is a block diagram showing an example of the lighting device 1 according to the embodiment. As shown in Fig. 11, the lighting device 1 according to the embodiment includes an electrode driving circuit 112, a memory circuit 113, a processing circuit 114, and a communication circuit 115 in addition to the optical element 100.

[0053] The memory circuit 113 is composed of, for example, a RAM, an EEPROM, a ROM, etc. The processing circuit 114 is composed of, for example, a microcomputer, etc. The communication circuit 115 receives light distribution data transmitted from the control device 300. The processing circuit 114 converts the light distribution data received by the communication circuit 115 into a predetermined gradation value. The electrode driving circuit 112 supplies a driving voltage corresponding to the gradation value converted by the processing circuit 114 to each of the driving electrodes 10, 13 of each liquid crystal cell 2 of the optical element 100. In addition to the above, the components that make up the lighting device 1 may also include various interface circuits, such as a power button and a mode selection switch.

[0054] Fig. 12 is a block diagram showing an example of a control device 300 according to an embodiment. As shown in Fig. 12, the control device 300 according to an embodiment includes a display panel 20, a touch sensor 30, a processing circuit 310, a detection circuit 311, a memory circuit 323, a communication circuit 325, a display control circuit 331, a speaker 401, and an amplifier circuit 402. The control device 300 according to an embodiment may also include a power button and a mode selection switch.

[0055] The display control circuit 331 is a circuit that executes display control processing for the display panel 20. The detection circuit 311 is a circuit that detects whether or not the touch sensor 30 has been touched, based on detection signals output from each detection element 31 of the touch sensor 30. The detection circuit 311 is configured with, for example, a detection IC. Alternatively, the detection circuit 311 and the display control circuit 331 may be mounted on the display panel 20 as a single display IC.

[0056] The processing circuit 310 is configured, for example, with a CPU, RAM, EEPROM, ROM, etc., of a smartphone, tablet, etc., that constitutes the control device 300. The display control circuit 331 may be a display IC mounted on the display panel 20 as described above, and may further be configured to include, for example, a GPU, etc., of a smartphone, tablet, etc., that constitutes the control device 300.

[0057] The processing circuit 310 controls the operation of the lighting device 1 based on the touch position detected by the detection circuit 311. In this embodiment, the processing circuit 310 has a function of executing control software for starting or stopping the light distribution control process. The processing circuit 310 is a component realized by, for example, a CPU of a smartphone, tablet, or the like that constitutes the control device 300.

[0058] The memory circuit 323 is composed of, for example, RAM, EEPROM, ROM, etc. of a smartphone, tablet, or the like that constitutes the control device 300.

[0059] In the present disclosure, music data is pre-stored in the memory circuit 323. In the present disclosure, the music data is exemplified by, but not limited to, uncompressed audio data such as WAV (RIFF waveform Audio Format). The music data may also be compressed audio data such as MP3 (MPEG-1 Audio Layer-3). The music data is format-converted into uncompressed PCM (pulse code modulation) data in the light distribution data generation process described below.

[0060] The processing circuit 310 converts the music data stored in the memory circuit 323 into a signal that conforms to the input format of the amplifier circuit 402. The amplifier circuit 402 amplifies the signal converted by the processing circuit 310 and supplies it to the speaker 401.

[0061] In addition, in the present disclosure, the memory circuitry 323 stores light distribution data generated in a light distribution data generation process described below.

[0062] The communication circuit 325 is configured, for example, by a wireless communication module of a smartphone, tablet, or the like that constitutes the control device 300. The communication circuit 325 transmits light distribution data to the lighting device 1.

[0063] In the present disclosure, the change range of the light distribution data corresponding to the music data is set, for example, linearly with respect to the music data.

[0064] Alternatively, if the range of change in the music data is small, or if the installation location of the lighting device 1 is large and the range of light irradiation by the lighting device 1 is relatively narrow, the range of change in the light distribution data may be set to be larger (for example, twice as large) than the range of change in the music data.

[0065] Furthermore, if the installation location of the lighting device 1 is small, the range of change of the light distribution data may be set to be smaller than the range of change of the music data (for example, 1 / 2).

[0066] Furthermore, the light distribution data may be the same in both the Dx direction and the Dy direction, or may be different data in the Dx direction and the Dy direction. Specifically, for example, the range of change of the light distribution data in the Dx direction may be set linearly with respect to the full-scale value of the music data, and the range of change of the light distribution data in the Dy direction may be set larger (or smaller) than the range of change of the music data, or the range of change of the light distribution data in the Dx direction may be set larger (or smaller) than the range of change of the music data, and the range of change of the light distribution data in the Dy direction may be set linearly with respect to the full-scale value of the music data.

[0067] Furthermore, if the music data is a stereo sound source, it is also possible to generate light distribution data in the Dx direction based on right audio data (or left audio data), and generate light distribution data in the Dy direction based on left audio data (or right audio data).

[0068] For ease of explanation, the following describes an example in which music data used to generate light distribution data is a monaural sound source, and light distribution data common to two directions, the Dx direction and the Dy direction, is generated from the monaural sound source.

[0069] Fig. 13 is a conceptual diagram showing an example of music data. Here, an example of generating light distribution data from uncompressed sound source data (binary data) is described. In Fig. 13, the horizontal axis represents time, and the vertical axis represents the data value (binary data) of the music data.

[0070] In the present disclosure, the processing circuit 310 of the control device 300 divides music data into multiple time-series music data and generates time-series light distribution data corresponding to the multiple time-series music data based on statistical values ​​of each time-series music data. Examples of the statistical values ​​of each time-series music data include an average value, maximum value, minimum value, etc. of binary data included in each time-series music data.

[0071] In the example shown in FIG. 13 , music data with a playback time (length of music) T is divided into N parts, and the application period of each piece of time-series light distribution data corresponding to the plurality of pieces of time-series music data is Tn (n is a natural number from 1 to N). Hereinafter, n pieces of time-series music data included in the music data will also be referred to as "nth time-series music data An." Furthermore, n pieces of time-series light distribution data corresponding to the nth time-series music data An will also be referred to as "nth time-series light distribution data Dn." Furthermore, each application period Tn of the nth time-series light distribution data Dn applied in the light distribution control of the lighting device 1 will also be referred to as "nth time-series light distribution data application period Tn." The total number of time-series light distribution data is equal to the division number N of the music data. The total number of time-series light distribution data is equal to the division number N of the music data.

[0072] 14 is a flowchart showing an example of the light distribution data generation process. In the present disclosure, the light distribution data generation process is executed by audio editing software running on the control device 300.

[0073] The processing circuit 310 reads music data from the storage circuit 323 (step S001) and performs format conversion of the read music data (step S002). Specifically, the music data is converted into 8-bit / 6-kHz sampling monaural uncompressed PCM data. The present disclosure is not limited to this format conversion process.

[0074] Processing circuitry 310 sets an n-th time-series light distribution data application period Tn for the music data after the format conversion process (step S003), and stores the n-th time-series light distribution data application period Tn in memory circuitry 323. As a method for setting the n-th time-series light distribution data application period Tn, for example, it may be possible to divide the music data into n pieces of n-th time-series music data An of a predetermined length (for example, 1 s) and set the n-th time-series light distribution data application period Tn, or it may be possible to detect interbeats based on the periodicity of the music data (for example, beats, rhythm, tempo, etc.), divide the data into n pieces of n-th time-series music data An, and set the n-th time-series light distribution data application period Tn.

[0075] Setting n=0 (step S004), and then setting n=n+1 (step S005), processing circuitry 310 calculates a statistical value BinAn of the multiple binary data included in the n-th time-series music data An (step S006), converts it into n-th time-series light distribution data Dn (step S007), and stores it in memory circuitry 323. In the present disclosure, the n-th time-series light distribution data Dn is stored in memory circuitry 323 in association with the n-th time-series light distribution data application period Tn.

[0076] Processing circuitry 310 then determines whether n = N (step S008). If n = N is not true (step S008; No), processing circuitry 310 returns to step S005 and repeatedly executes the processing up to step S008. If n = N is true (step S008; Yes), processing circuitry 310 terminates the light distribution data generation processing shown in FIG. 13.

[0077] (Embodiment 1) A specific example of light distribution control processing according to embodiment 1 will be described below. Fig. 15 is a flowchart showing an example of light distribution control processing according to embodiment 1. In the present disclosure, it is assumed that the system times of the control device 300 and the lighting device 1 are the same.

[0078] 15 is started in lighting system 200, control device 300 transmits light distribution data to lighting device 1 in synchronization with music data being played by the control device 300. Specifically, in the first embodiment, control device 300 sequentially reads out n-th time-series light distribution data Dn stored in memory circuit 323 together with n-th time-series light distribution data application period Tn, and transmits these to lighting device 1.

[0079] In the first embodiment, the light distribution control process is started by, for example, control software running on the control device 300. Specifically, the light distribution control process may be started by selecting an object provided on the display screen of the control software, or may be started by a timer or the like.

[0080] When the light distribution control process shown in Fig. 15 starts, the lighting system 200 executes initial synchronization processing between the control device 300 and the lighting device 1 (step S100). Fig. 16 is a sub-flowchart showing an example of the initial synchronization processing in the control device 300 of the light distribution control process according to embodiment 1. Fig. 17 is a sub-flowchart showing an example of the initial synchronization processing in the lighting device 1 of the light distribution control process according to embodiment 1. Fig. 18 is a sequence diagram showing an example of the initial synchronization processing of the light distribution control process according to embodiment 1.

[0081] In the initial synchronization process (step S100), first, the control device 300 transmits an initial synchronization start flag IS to the lighting device 1 (step S101). The lighting device 1 determines whether or not it has received the initial synchronization start flag IS (step S102), and if it has not received the flag IS (step S102; No), it repeats the process of step S102.

[0082] When the initial synchronization start flag IS is received (Step S102; Yes), the lighting device 1 transmits ACK data indicating that the initial synchronization start flag IS has been received, together with the current time RT1 (Step S103).

[0083] The control device 300 determines whether or not ACK data with the time RT1 attached has been received (step S104), and if not (step S104; No), repeats the process of step S104.

[0084] Upon receiving the ACK data with the time RT1 attached (step S104; Yes), the control device 300 stores the time RT1 in the memory circuitry 323, and also attaches a first transmission delay time DTPS indicating the transmission delay time from the lighting device 1 to the control device 300 to the first time-series light distribution data D1 and the first time-series light distribution data application period T1, and transmits them to the lighting device 1 (step S105). In the first embodiment, the first transmission delay time DTPS can be expressed by the following equation (1), where RT2 is the current time at which the control device 300 transmits the first transmission delay time DTPS. The first transmission delay time DTPS may also be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (1).

[0085] DTPS=RT2-RT1...(1)

[0086] The lighting device 1 determines whether or not it has received the first time-series light distribution data D1 with the first transmission delay time DTPS and the first time-series light distribution data application period T1 (step S106), and if it has not received them (step S106; No), it repeatedly executes the processing of step S106.

[0087] Upon receiving the first time-series light distribution data D1 with the first transmission delay time DTPS and the first time-series light distribution data application period T1 (step S106; Yes), the lighting device 1 stores the first time-series light distribution data D1, the first time-series light distribution data application period T1, and the first transmission delay time DTPS in the memory circuitry 113, and also transmits ACK data indicating that the first time-series light distribution data D1 with the first transmission delay time DTPS and the first time-series light distribution data application period T1 have been received to the control device 300, along with the current time RT3 (first time) (step S107).The lighting device 1 then starts light distribution control applying the first time-series light distribution data D1 at time DT1 (third time) obtained by adding the first transmission delay time DTPS to the current time RT3 (first time) (step S108).

[0088] The control device 300 determines whether or not ACK data marked with time RT3 (first time) has been received (step S109), and if not (step S109; No), repeats the processing of step S109.

[0089] When ACK data with time RT3 (first time) is received (step S109; Yes), the control device 300 stores time RT3 (first time) in the memory circuit 323 and starts playing the music at time DT1 (second time), which is time RT3 (first time) plus the first transmission delay time DTPS (step S110).

[0090] In the light distribution control process according to the first embodiment, the time DT1 (second time) at which music playback starts in the control device 300 and the time DT1 (third time) at which light distribution control starts in the lighting device 1 are substantially the same time. This makes it possible to synchronize the music playback start time in the control device 300 and the light distribution control start time in the lighting device 1.

[0091] Returning to the light distribution control process shown in Fig. 15 , a synchronization control process is executed between the control device 300 and the lighting device 1 to perform light distribution control synchronized with music playback (step S200). Fig. 19 is a sub-flowchart showing an example of the synchronization control process in the control device 300 for the light distribution control process according to embodiment 1. Fig. 20 is a sub-flowchart showing an example of the synchronization control process in the lighting device 1 for the light distribution control process according to embodiment 1. Fig. 21 is a sequence diagram showing an example of the synchronization control process for the light distribution control process according to embodiment 1.

[0092] When the synchronization control process is started, the lighting device 1 resets the synchronization control timer Ts (Ts = 0, step S201). As a result, when the synchronization control process is executed after the initial synchronization process (step S100), the synchronization control timer Ts is started from the time when light distribution control is started by applying the first time-series light distribution data D1. Furthermore, when the synchronization control process is executed after the re-synchronization process (step S300) described later, the synchronization control timer Ts is started from the time when light distribution control is started by applying the p-th time-series light distribution data Dp.

[0093] Furthermore, the lighting device 1 resets the light distribution application timer Td (Td=0, step S202), thereby starting the light distribution application timer Td, which starts from the time when light distribution control is started by applying the n-th time-series light distribution data Dn.

[0094] Meanwhile, control device 300 increments the value of n (step S203), and transmits the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn to lighting device 1 (step S204).

[0095] The lighting device 1 determines whether or not the n-th time-series light distribution data Dn and the n-th time-series light distribution data application period Tn have been received (step S205), and if they have not been received (step S205; No), repeats the processing of step S205.

[0096] When the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn are received (step S205; Yes), the lighting device 1 stores the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn in the memory circuitry 113, and also acquires a light distribution application timer Td (step S206). The lighting device 1 determines whether the (n-1)th time-series light distribution data application period Tn-1 has elapsed (step S207). If the (n-1)th time-series light distribution data application period Tn-1 has not elapsed (Td<Tn-1; step S207; No), the lighting device 1 repeatedly executes the processes of steps S206 and S207.

[0097] When the application period Tn-1 of the (n-1)th time-series light distribution data has elapsed (Td≧Tn-1, step S207; Yes), the lighting device 1 performs light distribution control by applying the nth time-series light distribution data Dn (step S208), and transmits ACK data to the control device 300 indicating that light distribution control applying the nth time-series light distribution data Dn has started (step S209).

[0098] Next, the lighting device 1 calculates a cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts = 0 (step S201) to the (n-1)th time-series light distribution data Dn-1 (step S210). The cumulative application period ΣTi when the synchronization control process is performed after the initial synchronization process (step S100) can be expressed by the following formula (2). The cumulative application period ΣTi when the synchronization control process is performed after the resynchronization process (step S300) described later can be expressed by the following formula (3).

[0099] ΣTi=T1+...+Tn-1...(2)

[0100] ΣTi=Tp+...+Tn-1...(3)

[0101] Then, the lighting device 1 acquires a synchronous control timer Ts (step S211), and determines whether the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts=0 (step S201) to the (n-1)th time-series light distribution data Dn-1 has elapsed (step S212).

[0102] If the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts=0 (step S201) to the (n-1)th time-series light distribution data Dn-1 has not been exceeded (Ts≦ΣTi, step S212; No), the lighting device 1 repeatedly executes the processes from step S202 onwards.

[0103] If the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts = 0 (step S201) to the (n-1)th time-series light distribution data Dn-1 is exceeded (Ts > ΣTi, step S212; Yes), this indicates that a delay has occurred in the light distribution control for the music data. In this case, the lighting device 1 transmits a resynchronization request to the control device 300 (step S213), returns to the light distribution control process shown in FIG. 15 , and executes resynchronization processing between the music playback and the light distribution control between the control device 300 and the lighting device 1 (step S300).

[0104] Fig. 22 is a sub-flowchart showing an example of resynchronization processing in the control device 300 of the light distribution control processing according to embodiment 1. Fig. 23 is a sub-flowchart showing an example of resynchronization processing in the lighting device 1 of the light distribution control processing according to embodiment 1. Fig. 24 is a sequence diagram showing an example of resynchronization processing in the light distribution control processing according to embodiment 1.

[0105] When the control device 300 receives a resynchronization request transmitted from the lighting device 1 in the synchronization control process (step S200) (step S301), the control device 300 attaches the current time Rt1 to a resynchronization start flag RS and transmits the flag to the lighting device 1 (step S302).

[0106] The lighting device 1 determines whether or not it has received a resynchronization start flag RS with the time Rt1 attached (step S303), and if it has not received the flag (step S303; No), it repeats the processing of step S303.

[0107] When the resynchronization start flag RS with the time Rt1 attached (step S303; Yes), the lighting device 1 transmits ACK data indicating that the resynchronization start flag RS with the time Rt1 attached, together with a second transmission delay time DTSP indicating the transmission delay time from the control device 300 to the lighting device 1 (step S304). In the first embodiment, the second transmission delay time DTSP can be expressed by the following equation (4), where Rt2 is the current time at which the lighting device 1 transmits the second transmission delay time DTSP. The second transmission delay time DTSP may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (4).

[0108] DTSP=Rt2-Rt1...(4)

[0109] The control device 300 determines whether or not ACK data with the second transmission delay time DTSP attached has been received (step S305), and if not (step S305; No), repeats the processing of step S305.

[0110] Upon receiving the ACK data with the second transmission delay time DTSP (step S305; Yes), the control device 300 stores the second transmission delay time DTSP in the memory circuitry 113 and acquires the elapsed playback time tr of the current music data (step S306). The control device 300 also sets the p-th time-series light distribution data Dp to be applied in the light distribution control of the lighting device 1 upon resynchronization and calculates the light distribution control start timing DTp based on the p-th time-series light distribution data Dp (step S307). In the first embodiment, the light distribution control start timing DTp can be expressed by the following equation (5):

[0111] DTp=ΣTi(i=1→p)>tr+DTSP...(5)

[0112] Then, control device 300 sets the pth time-series light distribution data Dp set in step S307 as the nth time-series light distribution data Dn, sets the pth time-series light distribution data application period Tp as the nth time-series light distribution data application period Tn, attaches the light distribution control start timing DTp calculated in step S307 to the nth time-series light distribution data Dn, and transmits them to lighting device 1 (step S308).

[0113] The lighting device 1 determines whether or not it has received the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn, each having the light distribution control start timing DTp (step S309). If it has not received the data (step S309; ​​No), it repeatedly executes the processing of step S309.

[0114] Upon receiving the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn accompanied by the light distribution control start timing DTp (step S309; ​​Yes), the lighting device 1 stores the nth time-series light distribution data Dn, the nth time-series light distribution data application period Tn, and the light distribution control start timing DTp in the memory circuitry 113, and transmits ACK data indicating that the nth time-series light distribution data Dn accompanied by the light distribution control start timing DTp and the nth time-series light distribution data application period Tn have been received (step S310), and resumes light distribution control by applying the nth time-series light distribution data Dn (pth time-series light distribution data Dp) at the light distribution control start timing DTp (step S311).

[0115] The control device 300 determines whether or not ACK data has been received (step S312). If ACK data has not been received (step S312; No), the control device 300 repeats the processing of step S312. If ACK data has been received (step S312; Yes), the control device 300 returns to the light distribution control processing shown in FIG. 15 and executes synchronization control processing between the control device 300 and the lighting device 1 to perform light distribution control synchronized with music playback (step S200).

[0116] In the synchronization control process in the control device 300 shown in FIG. 19, the control device 300 determines whether or not ACK data indicating that light distribution control using the nth time-series light distribution data Dn has started has been received (step S214), and if ACK data has not been received (step S214; No), it repeatedly executes the process of step S214.

[0117] When ACK data is received (step S214; Yes), control device 300 determines whether the value of n matches the total number N of time-series light distribution data (step S215), and if the value of n is less than the total number N of time-series light distribution data (n<N, step S215; No), it repeats the processing from step S203 onwards. When the value of n matches the total number N of time-series light distribution data (n=N, step S215; Yes), it ends the synchronization control processing, and the light distribution control processing according to the first embodiment ends.

[0118] 25A and 25B are conceptual diagrams showing an example of the operation in the synchronization control process (step S200) according to embodiment 1. Fig. 25A and 25B show an example in which light distribution control is started (restarted) by applying the pth time-series light distribution data in the re-synchronization process (step S300).

[0119] More specifically, in the light distribution control process according to the first embodiment, in the resynchronization process of the lighting device 1 (see FIG. 23 ), after the lighting device 1 starts (resumes) light distribution control (step S311), the process returns to the synchronization control process (step S200) and resets the synchronization control timer Ts (Ts=0, step S201).

[0120] After repeating the processes from step S202 onward a plurality of times, the lighting device 1 receives the q-th time-series light distribution data Dq (step S205; Yes), calculates the cumulative application period ΣTi (i=p→q−1) from the p-th time-series light distribution data Dp applied at the time when Ts=0 (step S201) to the q−1-th time-series light distribution data Dq−1 (step S210), acquires a synchronization control timer Ts (step S211), and determines whether the time from the time when Ts=0 (step S201) to the current time has exceeded the cumulative application period ΣTi from the p-th time-series light distribution data Dp applied at the time when Ts=0 (step S201) to the q−1-th time-series light distribution data Dq−1 (step S212).

[0121] 25A shows an example in which the time from the time Ts = 0 (step S201) to the current time matches the cumulative application period ΣTi from the pth time-series light distribution data Dp to the q-1st time-series light distribution data Dq-1 applied at the time Ts = 0 (step S201) (step S212; No). If a delay in light distribution control for music data occurs, as shown in FIG. 25B, the time from the time Ts = 0 (step S201) to the current time exceeds the cumulative application period ΣTi from the pth time-series light distribution data Dp to the q-1st time-series light distribution data Dq-1 applied at the time Ts = 0 (step S201) (step S212; Yes). In the first embodiment, if a delay in light distribution control for music data occurs (step S212; Yes), a resynchronization request is sent to the control device 300 (step S213), and resynchronization processing (step S300) is executed. This makes it possible to recover from delays in light distribution control for music data.

[0122] (Modification) A specific example of light distribution control processing according to a modification of embodiment 1 will be described below. Fig. 26 is a flowchart showing an example of light distribution control processing according to a modification of embodiment 1.

[0123] In the first embodiment, a configuration has been described in which, in the synchronization control process of the lighting device 1 (see FIG. 20 ), a delay in light distribution control for music data is detected (step S212; Yes), a resynchronization request is sent to the control device 300 (step S213), and the resynchronization process (step S300) is executed. However, in a modified example of the first embodiment, a configuration will be described in which, in the synchronization control process of the control device 300, a delay in light distribution control for music data is detected and the resynchronization process (step S300a) is executed.

[0124] When the light distribution control process shown in Fig. 26 starts, the lighting system 200 executes initial synchronization processing between the control device 300 and the lighting device 1 (step S100a). Fig. 27 is a sub-flowchart showing an example of the initial synchronization processing in the control device 300 of the light distribution control process according to the modified example of the first embodiment. Fig. 28 is a sub-flowchart showing an example of the initial synchronization processing in the lighting device 1 of the light distribution control process according to the modified example of the first embodiment. Fig. 29 is a sequence diagram showing an example of the initial synchronization processing of the light distribution control process according to the modified example of the first embodiment.

[0125] In the initial synchronization process (step S100a), first, the control device 300 attaches the current time RT1 to an initial synchronization start flag IS and transmits it (step S101a) to the lighting device 1. The lighting device 1 determines whether or not it has received the initial synchronization start flag IS with the time RT1 attached (step S102a), and if it has not received it (step S102a; No), it repeatedly executes the process of step S102a.

[0126] When the lighting device 1 receives the initial synchronization start flag IS with the time RT1 attached (step S102a; Yes), the lighting device 1 stores the time RT1 in the memory circuit 113 and transmits ACK data indicating the reception of the initial synchronization start flag IS with the time RT1 attached, together with a first transmission delay time DTSP1 indicating the transmission delay time from the control device 300 to the lighting device 1 (step S103a). In a modification of the first embodiment, the first transmission delay time DTSP1 can be expressed by the following equation (6), where RT2 is the current time at which the lighting device 1 transmits the first transmission delay time DTSP1. The first transmission delay time DTSP1 may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (6).

[0127] DTSP1=RT2-RT1...(6)

[0128] The control device 300 determines whether or not ACK data with the first transmission delay time DTSP1 has been received (step S104a), and if not (step S104a; No), repeats the processing of step S104a.

[0129] When the control device 300 receives the ACK data with the first transmission delay time DTSP1 attached (step S104a; Yes), it stores the first transmission delay time DTSP1 in the memory circuitry 323, attaches the current time RT3 (first time) to the first time-series light distribution data D1 and the first time-series light distribution data application period T1, and transmits them to the lighting device 1 (step S105a), and starts music playback at time DT1 (second time) obtained by adding the first transmission delay time DTSP1 to time RT3 (first time) (step S106a).

[0130] The lighting device 1 determines whether or not it has received the first time-series light distribution data D1 marked with time RT3 (first time) and the first time-series light distribution data application period T1 (step S107a), and if it has not received them (step S107a; No), it repeatedly executes the processing of step S107a.

[0131] Upon receiving the first time-series light distribution data D1 with the time RT3 (first time) and the first time-series light distribution data application period T1 (step S107a; Yes), the lighting device 1 stores the first time-series light distribution data D1, the first time-series light distribution data application period T1, and the time RT3 (first time) in the memory circuitry 113, and starts light distribution control applying the first time-series light distribution data D1 at the time DT1 (third time) obtained by adding the first transmission delay time DTSP1 to the time RT3 (first time) (step S108a).

[0132] In the light distribution control process according to the modification of the first embodiment, the time DT1 (second time) at which music playback starts in the control device 300 and the time DT1 (third time) at which light distribution control starts in the lighting device 1 are substantially the same time. This makes it possible to synchronize the music playback start time in the control device 300 and the light distribution control start time in the lighting device 1.

[0133] Returning to the light distribution control process shown in Fig. 26 , synchronization control process is executed to perform light distribution control synchronized with music playback between the control device 300 and the lighting device 1 (step S200a). Fig. 30 is a sub-flowchart showing an example of synchronization control process in the control device 300 for light distribution control process according to a modification of embodiment 1. Fig. 31 is a sub-flowchart showing an example of synchronization control process in the lighting device 1 for light distribution control process according to a modification of embodiment 1. Fig. 32 is a sequence diagram showing an example of synchronization control process in the light distribution control process according to a modification of embodiment 1.

[0134] When the synchronization control process is started, the control device 300 resets the synchronization control timer Ts (Ts = 0, step S201a). As a result, when the synchronization control process is executed after the initial synchronization process (step S100a), the synchronization control timer Ts is started from the time when the first time-series light distribution data D1 is applied and light distribution control is started. Furthermore, when the synchronization control process is executed after the resynchronization process (step S300a) described later, the synchronization control timer Ts is started from the time when the p-th time-series light distribution data Dp is applied and light distribution control is started.

[0135] Furthermore, control device 300 increments the value of n (step S202a), and transmits the n-th time-series light distribution data Dn and the n-th time-series light distribution data application period Tn to lighting device 1 (step S203a).

[0136] Meanwhile, the lighting device 1 resets the light distribution application timer Td (Td=0, step S204a), thereby starting the light distribution application timer Td, which starts from the time when light distribution control is started by applying the n-th time-series light distribution data Dn.

[0137] The lighting device 1 determines whether or not the n-th time-series light distribution data Dn and the n-th time-series light distribution data application period Tn have been received (step S205a), and if they have not been received (step S205a; No), repeats the processing of step S205a.

[0138] When the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn are received (step S205a; Yes), the lighting device 1 stores the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn in the memory circuitry 113, and also acquires a light distribution application timer Td (step S206a). The lighting device 1 determines whether the (n-1)th time-series light distribution data application period Tn-1 has elapsed (step S207a). If the (n-1)th time-series light distribution data application period Tn-1 has not elapsed (Td<Tn-1; step S207a; No), the lighting device 1 repeatedly executes the processes of steps S206a and S207a.

[0139] When the application period Tn-1 of the (n-1)th time-series light distribution data has elapsed (Td≧Tn-1, step S207a; Yes), the lighting device 1 performs light distribution control by applying the nth time-series light distribution data Dn (step S208a), transmits ACK data to the control device 300 indicating that light distribution control applying the nth time-series light distribution data Dn has started (step S209a), and repeatedly executes the processes from step S204a onwards.

[0140] The control device 300 determines whether or not ACK data indicating that light distribution control using the nth time-series light distribution data Dn has started has been received (step S210a), and if ACK data has not been received (step S210a; No), repeats the processing of step S210a.

[0141] When ACK data indicating that light distribution control applying the nth time-series light distribution data Dn has started (step S210a; Yes), control device 300 calculates a cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts = 0 (step S201a) to the (n-1)th time-series light distribution data Dn-1 (step S211a). The cumulative application period ΣTi when synchronization control processing is performed after initial synchronization processing (step S100a) can be expressed by the following equation (7). The cumulative application period ΣTi when synchronization control processing is performed after resynchronization processing (step S300a), which will be described later, can be expressed by the following equation (8).

[0142] ΣTi=T1+...+Tn-1...(7)

[0143] ΣTi=Tp+...+Tn-1...(8)

[0144] Then, the control device 300 acquires the synchronous control timer Ts (step S212a), and determines whether the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts=0 (step S201a) to the (n-1)th time-series light distribution data Dn-1 has elapsed (step S213a).

[0145] If the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts = 0 (step S201a) to the (n-1)th time-series light distribution data Dn-1 has been exceeded (Ts > ΣTi, step S213a; Yes), this indicates that a delay has occurred in the light distribution control for the music data. In this case, the process returns to the light distribution control process shown in Fig. 26 , and a process of resynchronizing music playback and light distribution control is performed between the control device 300 and the lighting device 1 (step S300a).

[0146] Fig. 33 is a sub-flowchart showing an example of resynchronization processing in the control device 300 of the light distribution control processing according to the modified example of embodiment 1. Fig. 34 is a sub-flowchart showing an example of resynchronization processing in the lighting device 1 of the light distribution control processing according to the modified example of embodiment 1. Fig. 35 is a sequence diagram showing an example of resynchronization processing in the light distribution control processing according to the modified example of embodiment 1.

[0147] When the process proceeds to the resynchronization process (step S300a), the control device 300 attaches the current time Rt1 to the resynchronization start flag RS and transmits it to the lighting device 1 (step S301a).

[0148] The lighting device 1 determines whether or not it has received a resynchronization start flag RS with the time Rt1 attached (step S302a), and if it has not received the flag (step S302a; No), it repeats the processing of step S302a.

[0149] When the resynchronization start flag RS with the time Rt1 attached (step S302a; Yes), the lighting device 1 stores the time Rt1 in the memory circuit 113, and transmits ACK data indicating the reception of the resynchronization start flag RS with the time Rt1 attached, together with a second transmission delay time DTSP2 indicating the transmission delay time from the control device 300 to the lighting device 1 (step S303a). In a modification of the first embodiment, the second transmission delay time DTSP2 can be expressed by the following equation (9), where Rt2 is the current time at which the lighting device 1 transmits the second transmission delay time DTSP2. The second transmission delay time DTSP2 may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (9).

[0150] DTSP2=Rt2-Rt1...(9)

[0151] The control device 300 determines whether or not ACK data with the second transmission delay time DTSP2 has been received (step S304a), and if not (step S304a; No), repeats the processing of step S304a.

[0152] When the control device 300 receives the ACK data with the second transmission delay time DTSP2 attached (step S304a; Yes), it stores the second transmission delay time DTSP2 in the memory circuitry 323, acquires the elapsed playback time tr of the current music data (step S305a), sets the p-th time-series light distribution data Dp to be applied in the light distribution control of the lighting device 1 upon resynchronization, and calculates the light distribution control start timing DTp based on the p-th time-series light distribution data Dp (step S306a). In the modified example of the first embodiment, the light distribution control start timing DTp can be expressed by the following equation (10):

[0153] DTp=ΣTi(i=1→p)>tr+DTSP2...(10)

[0154] Then, the control device 300 sets the pth time-series light distribution data Dp set in step S306a as the nth time-series light distribution data Dn, sets the pth time-series light distribution data application period Tp as the nth time-series light distribution data application period Tn, attaches the light distribution control start timing DTp calculated in step S306a to the nth time-series light distribution data Dn, and transmits them to the lighting device 1 (step S307a).

[0155] The lighting device 1 determines whether or not it has received the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn, each having the light distribution control start timing DTp (step S308a), and if it has not received them (step S308a; No), it repeatedly executes the processing of step S308a.

[0156] Upon receiving the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn accompanied by the light distribution control start timing DTp (step S308a; Yes), the lighting device 1 stores the nth time-series light distribution data Dn, the nth time-series light distribution data application period Tn, and the light distribution control start timing DTp in the memory circuitry 113, and transmits ACK data indicating that the nth time-series light distribution data Dn accompanied by the light distribution control start timing DTp and the nth time-series light distribution data application period Tn have been received (step S309a), and resumes light distribution control by applying the nth time-series light distribution data Dn (pth time-series light distribution data Dp) at the light distribution control start timing DTp (step S310a).

[0157] The control device 300 determines whether or not ACK data has been received (step S311a). If ACK data has not been received (step S311a; No), the control device 300 repeats the processing of step S311a. If ACK data has been received (step S311a; Yes), the control device 300 returns to the light distribution control processing shown in FIG. 26 and executes synchronization control processing between the control device 300 and the lighting device 1 to perform light distribution control synchronized with music playback (step S200a).

[0158] 30 , if the cumulative application period ΣTi from the time-series light distribution data applied at the time when Ts = 0 (step S201a) to the (n-1)th time-series light distribution data Dn-1 is not exceeded (Ts≦ΣTi, step S213a; No), control device 300 determines whether the value of n matches the total number N of time-series light distribution data (step S214a). If the value of n is less than the total number N of time-series light distribution data (n<N, step S214a; No), control device 300 repeatedly executes the processes from step S202a onward. If the value of n matches the total number N of time-series light distribution data (n=N, step S214a; Yes), the synchronization control process is terminated, and the light distribution control process according to the modification of embodiment 1 is terminated.

[0159] In the light distribution control process according to the modification of the first embodiment, in the resynchronization process of the lighting device 1 (see FIG. 34 ), after the lighting device 1 starts (resumes) light distribution control (step S310a), the process returns to the synchronization control process (step S200a), and the control device 300 resets the synchronization control timer Ts (Ts=0, step S201a).

[0160] After repeating the processes from step S202a onwards a plurality of times, the CPU 11 receives ACK data indicating that light distribution control applying the nth time-series light distribution data Dn from the lighting device 1 has started (step S210a; Yes), calculates the cumulative application period ΣTi (i=p→q−1) from the pth time-series light distribution data Dp applied at the time Ts=0 (step S201a) to the q−1th time-series light distribution data Dq−1 (step S211a), and determines whether the time from the time Ts=0 (step S201a) to the current time has exceeded the cumulative application period ΣTi from the pth time-series light distribution data Dp applied at the time Ts=0 (step S201a) to the q−1st time-series light distribution data Dq−1 (step S213a).

[0161] If a delay occurs in light distribution control for music data, the time from the time Ts = 0 (step S201a) to the current time will exceed the cumulative application period ΣTi from the pth time-series light distribution data Dp to the q-1st time-series light distribution data Dq-1 applied at the time Ts = 0 (step S201a) (step S213a; Yes). In a modification of the first embodiment, if a delay occurs in light distribution control for music data (step S213a; Yes), a resynchronization process (step S300a) is executed. This makes it possible to recover from the delay in light distribution control for music data.

[0162] Second Embodiment A specific example of the light distribution control process according to the second embodiment will be described below. Fig. 36 is a flowchart showing an example of the light distribution control process according to the second embodiment.

[0163] In the second embodiment, a case will be described in which, in the synchronization control process of the lighting device 1 (see FIG. 20 ), a delay in light distribution control for music data is detected (step S212; Yes), a resynchronization request is sent to the control device 300 (step S213), and the resynchronization process (step S300b) is executed, during which music playback is paused.

[0164] Fig. 37 is a sub-flowchart showing an example of resynchronization processing in the control device 300 for light distribution control processing according to embodiment 2. Fig. 38 is a sub-flowchart showing an example of resynchronization processing in the lighting device 1 for light distribution control processing according to embodiment 2. Fig. 39 is a sequence diagram showing an example of resynchronization processing for light distribution control processing according to embodiment 2.

[0165] When the control device 300 receives a resynchronization request transmitted from the lighting device 1 during the synchronization control process (step S200) (step S301b), it pauses the playback of the music data (step S302b), obtains the elapsed playback time ts at the time when the playback of the music data was paused (step S303b), and transmits a resynchronization start flag RS to the lighting device 1 (step S304b).

[0166] The lighting device 1 determines whether or not the resynchronization start flag RS has been received (step S305b), and if the resynchronization start flag RS has not been received (step S305b; No), the lighting device 1 repeatedly executes the processing of step S305b.

[0167] When the resynchronization start flag RS is received (step S305b; Yes), the lighting device 1 transmits ACK data indicating that the resynchronization start flag RS has been received, together with the current time Rt1 (step S306b).

[0168] The control device 300 determines whether or not ACK data with the time Rt1 attached has been received (step S307b), and if not (step S307b; No), repeats the process of step S307b.

[0169] Upon receiving the ACK data with time Rt1 attached (step S307b; Yes), the control device 300 stores time Rt1 in the storage circuit 323, sets the pth time-series light distribution data Dp to be applied in the light distribution control of the lighting device 1 upon resynchronization, and calculates the light distribution control start timing DTp based on the pth time-series light distribution data Dp (step S308b). The control device 300 then sets the pth time-series light distribution data Dp set in step S308b as the nth time-series light distribution data Dn and the pth time-series light distribution data application period Tp as the nth time-series light distribution data application period Tn, attaches a second transmission delay time DTPS2 indicating a transmission delay time from the lighting device 1 to the control device 300 to the nth time-series light distribution data Dn (pth time-series light distribution data Dp) and the nth time-series light distribution data application period Tn (pth time-series light distribution data application period Tp), and transmits them to the lighting device 1 (step S309b).

[0170] In the second embodiment, the second transmission delay time DTPS2 can be expressed by the following formula (11), where Rt2 is the current time at which the control device 300 transmits the nth time-series light distribution data Dn (pth time-series light distribution data Dp) with the light distribution control start timing DTp attached and the nth time-series light distribution data application period Tn (pth time-series light distribution data application period Tp). The second transmission delay time DTPS2 may be a value obtained by adding an arbitrary predetermined value ΔD to the following formula (11).

[0171] DTPS2=Rt2-Rt1...(11)

[0172] In the second embodiment, the light distribution control start timing DTp can be expressed by the following equation (12) using the second transmission delay time DTPS2.

[0173] DTp=ΣTi(i=1→p)>ts+DTPS2...(12)

[0174] The lighting device 1 determines whether or not it has received the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn, each having the second transmission delay time DTPS2 attached thereto (step S310b). If it has not received the data (step S310b; No), it repeatedly executes the processing of step S310b.

[0175] Upon receiving the nth time-series light distribution data Dn with the second transmission delay time DTPS2 and the nth time-series light distribution data application period Tn (step S310b; Yes), the lighting device 1 stores the nth time-series light distribution data Dn, the nth time-series light distribution data application period Tn, and the second transmission delay time DTPS2 in the memory circuitry 113, and also transmits ACK data indicating that the nth time-series light distribution data Dn with the second transmission delay time DTPS2 and the nth time-series light distribution data application period Tn have been received to the control device 300, along with the current time Rt3 (first time) (step S311b). At time Dt1 (third time) obtained by adding the second transmission delay time DTPS2 to the current time Rt3 (first time), the lighting device 1 resumes light distribution control by applying the nth time-series light distribution data Dn (pth time-series light distribution data Dp) (step S312b).

[0176] The control device 300 determines whether ACK data marked with time Rt3 (first time) has been received (step S313b; No). If not (step S313b; No), it repeats the process of step S313b. If ACK data marked with time Rt3 (first time) has been received (step S313b; Yes), it stores time Rt3 (first time) in the memory circuit 323 and resumes playback of the music data at time Dt1 (second time) obtained by adding the second transmission delay time DTPS2 to the current time Rt3 (first time) (step S314b). Then, the process returns to the light distribution control process shown in FIG. 36 , and executes synchronization control process (step S200) to perform light distribution control between the control device 300 and the lighting device 1 in synchronization with music playback.

[0177] (Modification) A specific example of light distribution control processing according to a modification of embodiment 2 will be described below. Fig. 40 is a flowchart showing an example of light distribution control processing according to a modification of embodiment 2.

[0178] In the second embodiment, a mode in which music playback is paused during the synchronization control process of the lighting device 1 (see FIG. 20 ) is detected when a delay in light distribution control for music data is detected (step S212; Yes), a resynchronization request is sent to the control device 300 (step S213), and the resynchronization process (step S300b) is executed, has been described. However, in a modified example of the second embodiment, a mode in which music playback is paused during the synchronization control process of the control device 300 (see FIG. 30 ) is detected when a delay in light distribution control for music data is detected (step S213a; Yes), and the resynchronization process (step S300c) is executed, will be described.

[0179] Fig. 41 is a sub-flowchart showing an example of resynchronization processing in the control device 300 of the light distribution control processing according to the modified example of embodiment 2. Fig. 42 is a sub-flowchart showing an example of resynchronization processing in the lighting device 1 of the light distribution control processing according to the modified example of embodiment 2. Fig. 43 is a sequence diagram showing an example of resynchronization processing in the light distribution control processing according to the modified example of embodiment 2.

[0180] When the resynchronization process (step S300c) begins, the control device 300 temporarily suspends playback of the music data (step S301c), acquires the elapsed playback time ts at the time playback of the music data was paused (step S302c), and sends the resynchronization start flag RS with the current time Rt1 attached to it to the lighting device 1 (step S303c).

[0181] The lighting device 1 determines whether or not it has received a resynchronization start flag RS with the time Rt1 attached (step S304c), and if it has not received the flag (step S304c; No), it repeats the processing of step S304c.

[0182] When the resynchronization start flag RS with the time Rt1 attached (step S304c; Yes), the lighting device 1 stores the time Rt1 in the memory circuit 113, and transmits ACK data indicating the reception of the resynchronization start flag RS with the time Rt1 attached, together with a second transmission delay time DTSP2 indicating the transmission delay time from the control device 300 to the lighting device 1 (step S305c). In the second embodiment, the second transmission delay time DTSP2 can be expressed by the following equation (13), where Rt2 is the current time at which the lighting device 1 transmits the second transmission delay time DTSP2. The second transmission delay time DTSP2 may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (13).

[0183] DTSP2=Rt2-Rt1...(13)

[0184] The control device 300 determines whether or not ACK data with the second transmission delay time DTSP2 has been received (step S306c), and if not (step S306c; No), repeats the processing of step S306c.

[0185] When the control device 300 receives the ACK data with the second transmission delay time DTSP2 attached (step S306c; Yes), it stores the second transmission delay time DTSP2 in the memory circuit 323, sets the p-th time-series light distribution data Dp to be applied in the light distribution control of the lighting device 1 upon resynchronization, and calculates the light distribution control start timing DTp based on the p-th time-series light distribution data Dp (step S307c).

[0186] In the modified example of the second embodiment, the light distribution control start timing DTp can be expressed by the following equation (14) using the second transmission delay time DTSP2.

[0187] DTp=ΣTi(i=1→p)>ts+DTSP2...(14)

[0188] Then, the control device 300 sets the pth time-series light distribution data Dp set in step S307c as the nth time-series light distribution data Dn and the pth time-series light distribution data application period Tp as the nth time-series light distribution data application period Tn, appends the current time Rt3 (first time) to the nth time-series light distribution data Dn (pth time-series light distribution data Dp) and the nth time-series light distribution data application period Tn (pth time-series light distribution data application period Tp), and transmits them to the lighting device 1 (step S308c), and resumes music playback at time Dt1 (second time) obtained by adding the second transmission delay time DTSP2 to time Rt3 (first time) (step S309c).

[0189] The lighting device 1 determines whether or not it has received the nth time-series light distribution data Dn marked with time Rt3 (first time) and the nth time-series light distribution data application period Tn (step S310c), and if it has not received them (step S310c; No), it repeatedly executes the processing of step S310c.

[0190] Upon receiving the nth time-series light distribution data Dn and the nth time-series light distribution data application period Tn, each marked with time Rt3 (first time) (step S310c; Yes), the lighting device 1 stores the nth time-series light distribution data Dn, the nth time-series light distribution data application period Tn, and time Rt3 (first time) in the memory circuitry 113, and resumes light distribution control by applying the nth time-series light distribution data Dn (the pth time-series light distribution data Dp) at time Dt1 (third time) obtained by adding the second transmission delay time DTSP2 to time Rt3 (first time) (step S311c). The process then returns to the light distribution control process shown in FIG. 40 , where the lighting device 1 and the control device 300 execute synchronization control processing to perform light distribution control synchronized with music playback (step S200a).

[0191] (Embodiment 3) A specific example of light distribution control processing according to embodiment 3 will be described below. Fig. 44 is a flowchart showing an example of light distribution control processing according to embodiment 3. Fig. 45 is a sub-flowchart showing an example of processing in the control device 300 for light distribution control processing according to embodiment 3. Fig. 46 is a sub-flowchart showing an example of processing in the lighting device 1 for light distribution control processing according to embodiment 3. Fig. 47 is a sequence diagram showing an example of light distribution control processing according to embodiment 3.

[0192] In the third embodiment, the n-th time-series light distribution data Dn is associated with the n-th time-series light distribution data application period Tn corresponding to the n-th time-series light distribution data Dn and is stored in advance in the storage circuit 113 of the lighting device 1.

[0193] In the light distribution control process (step S400) according to the third embodiment, first, the control device 300 transmits a synchronization start flag SY to the lighting device 1 (step S401). The lighting device 1 determines whether or not it has received the synchronization start flag SY (step S402), and if it has not received the flag (step S402; No), it repeatedly executes the process of step S402.

[0194] When the synchronization start flag SY is received (step S402; Yes), the lighting device 1 transmits ACK data indicating that the synchronization start flag SY has been received, together with the current time RT1 (step S403).

[0195] The control device 300 determines whether or not ACK data with the time RT1 attached has been received (step S404), and if not (step S404; No), repeats the process of step S404.

[0196] When the control device 300 receives the ACK data with the time RT1 attached (step S404; Yes), the control device 300 stores the time RT1 in the memory circuitry 323 and transmits a transmission delay time DTPS indicating the transmission delay time from the lighting device 1 to the control device 300 to the lighting device 1 (step S405). In the third embodiment, the transmission delay time DTPS can be expressed by the following equation (15) where RT2 is the current time when the control device 300 transmits the transmission delay time DTPS. The transmission delay time DTPS may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (15).

[0197] DTPS=RT2-RT1...(15)

[0198] The lighting device 1 determines whether or not the transmission delay time DTPS has been received (step S406), and if not (step S406; No), repeats the process of step S406.

[0199] When the transmission delay time DTPS is received (step S406; Yes), the lighting device 1 stores the transmission delay time DTPS in the memory circuit 113 and transmits ACK data indicating that the transmission delay time DTPS has been received to the control device 300 together with the current time RT3 (first time) (step S407).

[0200] The control device 300 determines whether or not ACK data marked with time RT3 (first time) has been received (step S408), and if not (step S408; No), repeats the processing of step S408.

[0201] When ACK data with time RT3 (first time) is received (step S408; Yes), the control device 300 stores time RT3 (first time) in the memory circuit 323 and determines whether the time obtained by adding the transmission delay time DTPS to time RT3 (first time) (second time) has arrived (step S409). If the time obtained by adding the transmission delay time DTPS to time RT3 (first time) (second time) has not arrived (step S409; No), the control device 300 repeats the process of step S409.

[0202] When the time RT3 (first time) plus the transmission delay time DTPS (second time) arrives (step S409; Yes), the control device 300 resets the synchronization control timer Ts (Ts=0, step S410) and starts music playback (step S411). This starts the synchronization control timer Ts, which starts from the time RT3 plus the transmission delay time DTPS (second time).

[0203] When music playback is started in step S411, the control device 300 determines whether the music data playback time T has elapsed from the time set as the starting point (Ts=0) in step S410 (step S412). If the music data playback time T has not elapsed (step S412; No), the process of step S412 is repeated. If the music data playback time T has elapsed (step S412; Yes), playback of the music data is stopped (step S413).

[0204] During the playback time T of the music data, the lighting device 1 sequentially reads out the nth time-series light distribution data Dn stored in the memory circuit 113 together with the nth time-series light distribution data application period Tn, and performs dynamic light distribution control synchronized with the music data.

[0205] Specifically, after transmitting ACK data with time RT3 (first time) to the control device 300 in step S407, the lighting device 1 determines whether the time obtained by adding the transmission delay time DTPS to the time RT3 (first time) (third time) has arrived (step S414). If the time obtained by adding the transmission delay time DTPS to the time RT3 (first time) (third time) has not arrived (step S414; No), the lighting device 1 repeatedly executes the processing of step S414.

[0206] When the time reaches the third time obtained by adding the transmission delay time DTPS to the time RT3 (first time) (step S414; Yes), the lighting device 1 resets the light distribution application timer Td (Td = 0, step S415), thereby starting the light distribution application timer Td, which starts from the time when light distribution control is started by applying the n-th time-series light distribution data Dn.

[0207] Then, the lighting device 1 increments the value of n (step S416), acquires a light distribution application timer Td (step S417), and determines whether the (n-1)th time-series light distribution data application period Tn-1 has elapsed (step S418). If the (n-1)th time-series light distribution data application period Tn-1 has not elapsed (Td<Tn-1; step S418; No), it repeatedly executes the processes of steps S417 and S418.

[0208] When the (n-1)th time-series light distribution data application period Tn-1 has elapsed (Td≧Tn-1, step S418; Yes), the lighting device 1 applies the nth time-series light distribution data Dn to perform light distribution control (step S419).

[0209] The lighting device 1 then determines whether the value of n matches the total number N of time-series light distribution data (step S420), and if the value of n is less than the total number N of time-series light distribution data (n<N, step S420; No), it repeats the processing from step S415 onwards. If the value of n matches the total number N of time-series light distribution data (n=N, step S420; Yes), it ends the synchronization processing and the light distribution control processing according to the third embodiment.

[0210] In the light distribution control process according to the third embodiment described above, the time (second time) at which music playback starts in the control device 300 and the time (third time) at which light distribution control starts in the lighting device 1 are substantially the same time. This makes it possible to synchronize the music playback start time in the control device 300 and the light distribution control start time in the lighting device 1.

[0211] (Modification) A specific example of light distribution control processing according to a modification of embodiment 3 will be described below. Fig. 48 is a flowchart showing an example of light distribution control processing according to a modification of embodiment 3. Fig. 49 is a sub-flowchart showing an example of processing in control device 300 for light distribution control processing according to a modification of embodiment 3. Fig. 50 is a sub-flowchart showing an example of processing in lighting device 1 for light distribution control processing according to a modification of embodiment 3. Fig. 51 is a sequence diagram showing an example of light distribution control processing according to a modification of embodiment 3.

[0212] Similarly, in the modification of the third embodiment, the n-th time-series light distribution data Dn is associated with the n-th time-series light distribution data application period Tn corresponding to the n-th time-series light distribution data Dn and is stored in advance in memory circuitry 113 of lighting device 1.

[0213] In the light distribution control process (step S400a) according to the modification of the third embodiment, first, the control device 300 assigns the current time RT1 to the synchronization start flag SY and transmits the flag (step S401a) to the lighting device 1. The lighting device 1 determines whether or not it has received the synchronization start flag SY with the time RT1 assigned (step S402a), and if it has not received the flag (step S402a; No), it repeatedly executes the process of step S402a.

[0214] When the synchronization start flag SY with the time RT1 attached is received (step S402a; Yes), the lighting device 1 stores the time RT1 in the memory circuit 113, and transmits ACK data indicating the reception of the synchronization start flag SY with the time RT1 attached, together with a transmission delay time DTSP indicating the transmission delay time from the control device 300 to the lighting device 1 (step S403a). In a modification of the third embodiment, the transmission delay time DTSP can be expressed by the following equation (16), where RT2 (first time) is the current time at which the lighting device 1 transmits the transmission delay time DTSP. The transmission delay time DTSP may be a value obtained by adding an arbitrary predetermined value ΔD to the following equation (16).

[0215] DTSP=RT2-RT1...(16)

[0216] The control device 300 determines whether or not ACK data with the transmission delay time DTSP attached has been received (step S404a), and if not (step S404a; No), repeats the process of step S404a.

[0217] When the control device 300 receives the ACK data with the transmission delay time DTSP attached (step S404a; Yes), it stores the transmission delay time DTSP in the memory circuit 323, transmits the current time RT3 (first time) to the lighting device 1 (step S405a), and determines whether the time obtained by adding the transmission delay time DTSP to the time RT3 (first time) (third time) has arrived (step S406a). If the time obtained by adding the transmission delay time DTSP to the time RT3 (first time) (third time) has not arrived (step S406a; No), it repeats the processing of step S406a.

[0218] When the time RT3 (first time) plus the transmission delay time DTSP arrives (third time) (step S406a; Yes), the control device 300 resets the synchronization control timer Ts (Ts=0, step S407a) and starts playing music (step S408a). This starts the synchronization control timer Ts, which starts from the time RT3 (first time) plus the transmission delay time DTSP (third time).

[0219] When music playback is started in step S408a, the control device 300 determines whether the music data playback time T has elapsed from the time set as the starting point (Ts=0) in step S407a (step S409a). If the music data playback time T has not elapsed (step S409a; No), the process of step S409a is repeated. If the music data playback time T has elapsed (step S409a; Yes), playback of the music data is stopped (step S410a).

[0220] During the playback time T of the music data, the lighting device 1 sequentially reads out the nth time-series light distribution data Dn stored in the memory circuit 113 together with the nth time-series light distribution data application period Tn, and performs dynamic light distribution control synchronized with the music data.

[0221] Specifically, the lighting device 1 determines whether or not it has received time RT3 (first time) (step S411a), and if it has not received time RT3 (step S411a; No), it repeats the process of step S411a.

[0222] When the lighting device 1 receives the time RT3 (first time) (step S411a; Yes), the lighting device 1 stores the time RT3 (first time) in the memory circuitry 113 and determines whether the time obtained by adding the transmission delay time DTSP to the time RT3 (first time) (second time) has arrived (step S412a). If the time obtained by adding the transmission delay time DTSP to the time RT3 (first time) (second time) has not arrived (step S412a; No), the lighting device 1 repeats the process of step S412a.

[0223] When the time reaches the second time obtained by adding the transmission delay time DTSP to time RT3 (first time) (step S412a; Yes), the lighting device 1 resets the light distribution application timer Td (Td=0, step S413a), thereby starting the light distribution application timer Td, which starts from the time when light distribution control is started by applying the n-th time-series light distribution data Dn.

[0224] Then, the lighting device 1 increments the value of n (step S414a), acquires a light distribution application timer Td (step S415a), and determines whether the (n-1)th time-series light distribution data application period Tn-1 has elapsed (step S416a). If the (n-1)th time-series light distribution data application period Tn-1 has not elapsed (Td<Tn-1; step S416a; No), it repeatedly executes the processes of steps S415a and S416a.

[0225] When the (n-1)th time-series light distribution data application period Tn-1 has elapsed (Td≧Tn-1, step S416a; Yes), the lighting device 1 applies the nth time-series light distribution data Dn to perform light distribution control (step S417a).

[0226] The lighting device 1 then determines whether the value of n matches the total number N of time-series light distribution data (step S418a), and if the value of n is less than the total number N of time-series light distribution data (n<N, step S418a; No), it repeatedly executes the processing from step S413a onwards. If the value of n matches the total number N of time-series light distribution data (n=N, step S418a; Yes), it ends the synchronization processing and terminates the light distribution control processing according to the modified example of embodiment 3.

[0227] In the light distribution control process according to the modification of the third embodiment described above, the time (second time) at which light distribution control is started in the lighting device 1 and the time (third time) at which music playback is started in the control device 300 are substantially the same time. This makes it possible to synchronize the music playback start time in the control device 300 and the light distribution control start time in the lighting device 1.

[0228] (Modification) Fig. 52 is a diagram showing a schematic configuration of a lighting system 200a according to a modification of the embodiment. Fig. 53 is a block diagram showing an example of a control device 300a according to a modification of the embodiment. Fig. 54 is a block diagram showing an example of a speaker device 400 according to a modification of the embodiment.

[0229] In a lighting system 200a according to a modified example of the embodiment, the control device 300a is configured by omitting the speaker 401 and the amplifier circuit 402 from the configuration of the control device 300 shown in FIG. 12, and is configured to include a speaker device 400 in addition to the lighting device 1 and the control device 300a.

[0230] The speaker device 400 includes a speaker 401, an amplifier circuit 402, a memory circuit 403, a processing circuit 404, and a communication circuit 405. The memory circuit 403 is configured with, for example, a RAM, an EEPROM, a ROM, etc. The processing circuit 404 is configured with, for example, a microcomputer, etc.

[0231] The communication circuit 405 receives music data transmitted from the control device 300a. The processing circuit 404 converts the music data received by the communication circuit 405 into a signal according to the input format of the amplifier circuit 402. The amplifier circuit 402 amplifies the signal converted by the processing circuit 404 and supplies it to the speaker 401. In addition to the above, the components constituting the speaker device 400 may also include various interface circuits such as a power button and a mode selection switch.

[0232] In the lighting system 200a according to the modified example of the embodiment, dynamic light distribution control synchronized with music playback can also be realized by the light distribution control process according to the above-described embodiments and their modified examples.

[0233] In the above-described embodiment, an example has been described in which music data used to generate light distribution data is a monaural sound source, and light distribution data common to the two directions, Dx and Dy, is generated from the monaural sound source, but as described above, it is also possible to generate light distribution data for the two directions, Dx and Dy, from a stereo sound source, and dynamically control the light distribution states in the two directions, Dx and Dy, independently. Alternatively, the range of change in the light distribution data in the Dx and Dy directions may be changed, or, for example, the directions of change in the light distribution data in the Dx and Dy directions may be reversed.

[0234] Furthermore, in the above-described embodiment, an example has been given of a configuration in which the light distribution control process is terminated after all of the light distribution data corresponding to one piece of music data has been applied, but the light distribution control process may also be terminated when the light distribution control process is stopped, for example, by control software running on the control devices 300, 300a, or by an interface circuit provided in the lighting device 1, the speaker device 400, or the lighting device 1.

[0235] Although preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible without departing from the spirit of the present disclosure. For example, if the lighting device of the present disclosure is capable of adjusting not only the light distribution shape but also the brightness and color of the light, a configuration for adjusting the brightness and color of the light using the configuration of the present disclosure can also be adopted. Appropriate modifications made without departing from the spirit of the present disclosure naturally fall within the technical scope of the present disclosure.

[0236] REFERENCE SIGNS LIST 1 lighting device 2 liquid crystal cell 2_1 first liquid crystal cell 2_2 second liquid crystal cell 2_3 third liquid crystal cell 2_4 fourth liquid crystal cell 4 light source 5 first substrate 6 second substrate 7 sealing material 8 liquid crystal layer 9 base material 10, 10a, 10b drive electrode 11 first metal wiring 11a, 11b, 11c, 11d metal wiring 12 base material 13, 13a, 13b drive electrode 14 second metal wiring 14a, 14b metal wiring 15a, 15b conductive portion 16a, 16b connection terminal portion 17 liquid crystal molecule 18 alignment film 19 alignment film 20 display panel 30 touch sensor 31 detection element 100 optical element 112 electrode drive circuit 113 memory circuit 114 processing circuit 115 communication circuit 200, 200a Lighting system 300, 300a Control device 310, 310a Processing circuit 311 Detection circuit 323 Memory circuit 325 Communication circuit 331 Display control circuit 400 Speaker device 401 Speaker 402 Amplifier circuit 403 Memory circuit 404 Processing circuit 405 Communication circuit AA Effective area GA Peripheral area

Claims

1. A lighting system comprising: a lighting device capable of controlling the light distribution state of light emitted from a light source; and a control device that plays music data and transmits light distribution data synchronized with time-series changes in the music data to the lighting device, thereby dynamically controlling the light distribution state of the lighting device, wherein the control device starts playing the music data at a second time obtained by adding a transmission delay time from the lighting device to the lighting device to a first time obtained by adding the transmission delay time to the first time, and the lighting device starts controlling the light distribution state at a third time obtained by adding the transmission delay time to the first time.

2. A lighting system comprising: a lighting device capable of controlling the light distribution state of light emitted from a light source; and a control device that plays music data and transmits light distribution data synchronized with time-series changes in the music data to the lighting device, thereby dynamically controlling the light distribution state of the lighting device, wherein the control device starts playing the music data at a second time obtained by adding a transmission delay time from the control device to the lighting device to a first time acquired by the control device, and the lighting device starts controlling the light distribution state at a third time obtained by adding the transmission delay time to the first time.

3. The lighting system according to claim 1 or 2, wherein the light distribution data includes a plurality of time-series light distribution data respectively corresponding to a plurality of time-series music data obtained by dividing the music data along a time series, and each of the plurality of time-series light distribution data has an application time set corresponding to a playback time of the time-series music data, and the control device transmits the plurality of time-series light distribution data to the lighting device sequentially along a time series.

4. The lighting system according to claim 3, wherein the lighting device transmits a resynchronization request to the control device when a period from the application timing of the pth time-series light distribution data to the application timing of the qth time-series light distribution data is longer than a cumulative application period from the pth time-series light distribution data to the q-1th time-series light distribution data.

5. The lighting system according to claim 4, wherein, when the control device receives the resynchronization request, the control device acquires the elapsed playback time of the music data, and transmits to the lighting device time-series light distribution data whose application timing is later than the time obtained by adding a transmission delay time from the control device to the lighting device to the elapsed playback time.

6. The lighting system according to claim 3, wherein the control device, when a period from the application timing of the pth time-series light distribution data to the application timing of the qth time-series light distribution data is longer than a cumulative application period from the pth time-series light distribution data to the q-1th time-series light distribution data, acquires an elapsed playback time of the music data, and transmits to the lighting device time-series light distribution data whose application timing is later than a time obtained by adding a transmission delay time from the control device to the lighting device to the elapsed playback time.

7. The lighting system according to claim 4, wherein, when the control device receives the resynchronization request, the control device pauses playback of the music data, acquires the elapsed playback time at the time when playback of the music data was paused, transmits to the lighting device time-series light distribution data whose application timing is later than the time obtained by adding a transmission delay time from the lighting device to the lighting device itself to the elapsed playback time, and resumes playback of the music data at a second time obtained by adding the transmission delay time from the lighting device to the lighting device itself to the first time acquired by the lighting device, and the lighting device resumes control of the light distribution state at a third time obtained by adding the transmission delay time to the first time.

8. The lighting system according to claim 3, wherein, when a period from the application timing of the pth time-series light distribution data to the application timing of the qth time-series light distribution data is longer than a cumulative application period from the pth time-series light distribution data to the q-1th time-series light distribution data, the control device temporarily suspends playback of the music data, acquires the elapsed playback time at the time when playback of the music data was paused, and transmits to the lighting device time-series light distribution data whose application timing is later than the time obtained by adding a transmission delay time from the control device to the lighting device to the elapsed playback time, and resumes playback of the music data at a second time obtained by adding the transmission delay time from the control device to the lighting device to the first time acquired in the control device, and the lighting device resumes control of the light distribution state at a third time obtained by adding the transmission delay time to the first time.

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