Illumination device

Abstract

This illumination device comprises a light source and a panel unit disposed in the optical axis of the light source. The panel unit has a plurality of liquid crystal panels laminated in a first direction along the optical axis, and an effective region in at least one of the plurality of liquid crystal panels includes a plurality of sub-regions. Each of the plurality of sub-regions is provided so as to be capable of switching between light transmission and light diffusion.

Description

lighting equipment

[0001] The present disclosure relates to a lighting device.

[0002] Conventionally, there has been a lighting device that combines a light source such as an LED with a thin lens engraved with a prism pattern, and changes 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 device that changes the brightness of the lighting over time to achieve a flickering light like a candle flame has been disclosed (see, for example, Patent Document 1).

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

[0004] The lighting device disclosed in Patent Document 1 has a complex configuration because it includes a dimming signal generation unit that issues dimming operation instructions for parameters including dimming output, flickering lighting cycle, and color tone.

[0005] An object of the present disclosure is to provide a lighting device that can achieve dynamic light distribution control using fluctuations with a simpler configuration.

[0006] An illumination device according to one aspect of the present disclosure includes a light source and a panel unit arranged on an optical axis of the light source, the panel unit having a plurality of liquid crystal panels stacked in a first direction along the optical axis, and an effective area of ​​at least one of the plurality of liquid crystal panels includes a plurality of partial areas, each of which is switchable between transmitting light and diffusing light.

[0007] FIG. 1 is a schematic diagram showing an illumination device according to a first embodiment. FIG. 2 is a perspective view showing a panel unit according to the first embodiment. FIG. 3 is a schematic diagram showing a cross section of a liquid crystal panel. FIG. 4 is a schematic diagram showing a first substrate as viewed from the Z direction. FIG. 5 is a schematic diagram showing a second substrate as viewed from the Z direction. FIG. 6 is a schematic diagram showing a liquid crystal panel as viewed from the Z direction. FIG. 7A is a diagram showing the alignment direction of an alignment film of a first substrate as viewed from the Z direction. FIG. 7B is a diagram showing the alignment direction of an alignment film of a second substrate as viewed from the Z direction. FIG. 8 is a conceptual diagram showing changes in the state of light passing through a panel unit according to the first embodiment. FIG. 9 is a conceptual diagram showing changes in the state of light passing through a panel unit according to the first embodiment. FIG. 10 is a block diagram of an illumination device according to the first embodiment. FIG. 11 is a schematic diagram showing four liquid crystal panels stacked in the Z direction. FIG. 12 is a schematic diagram showing how an image illuminated by a panel unit changes over time. FIG. 13 is a schematic diagram showing a liquid crystal panel according to a second embodiment. FIG. 14 is a schematic diagram of the first substrate viewed from the Z direction. FIG. 15 is a schematic diagram of the second substrate viewed from the Z direction. FIG. 16 is a schematic diagram showing four liquid crystal panels stacked in the Z direction. FIG. 17 is a schematic diagram showing how an image projected by a panel unit changes over time. FIG. 18 is a schematic diagram showing a liquid crystal panel according to a third embodiment. FIG. 19 is a schematic diagram of the first substrate viewed from the Z direction. FIG. 20 is a schematic diagram of the second substrate viewed from the Z direction. FIG. 21 is a schematic diagram showing a panel unit according to a fourth embodiment. FIG. 22 is a schematic diagram showing a panel unit according to a fifth embodiment. FIG. 23 is a schematic diagram showing a panel unit according to a sixth embodiment. FIG. 24 is a schematic diagram showing four liquid crystal panels stacked in the Z direction in a first modified example. FIG. 25 is a schematic diagram showing four liquid crystal panels stacked in the Z direction in a second modified example.

[0008] A detailed description of embodiments of the present invention will be given with reference to the drawings. The present invention is not limited to the following embodiments. The components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. 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 make while maintaining the gist of the invention are naturally included within the scope of the present invention. The drawings may also show schematic representations of the width, thickness, shape, etc. of each component compared to the actual embodiment for clarity. However, these are merely examples and are not intended to limit the interpretation of the present invention. In this specification and the drawings, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions may be omitted as appropriate. In the drawings, the Z direction is the stacking direction of the liquid crystal panel and the direction of the optical axis of the light source. The X direction is perpendicular to (intersects) the Z direction. The Y direction is perpendicular to (intersects) the Z direction and the X direction. The Z direction is also referred to as a first direction, and the Y direction is also referred to as a second direction.

[0009] First Embodiment First, a first embodiment will be described. Fig. 1 is a schematic diagram showing an illumination device according to the first embodiment. Fig. 2 is a perspective view showing a panel unit according to the first embodiment.

[0010] 1, the lighting device 1 includes a light source 33, a reflector 34, and a panel unit 100. The panel unit 100 is disposed on the optical axis of the light source 33. The optical axis extends along the Z direction (first direction).

[0011] As shown in FIG. 2 , the panel unit 100 includes a first liquid crystal panel 21, a second liquid crystal panel 22, a third liquid crystal panel 23, and a fourth liquid crystal panel 24. The first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 each have the same configuration. In the panel unit 100, the first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 are stacked in this order in the Z direction (first direction) from the Z2 side toward the Z1 side. In each liquid crystal panel, a second substrate 6 is stacked on the Z1 side (one side in the first direction) of the first substrate 5. Hereinafter, the first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 will be collectively referred to as the "liquid crystal panels 2."

[0012] The light source 33 is, for example, a light emitting diode (LED). The reflector 34 focuses the light from the light source 33 onto the panel unit 100. As described above, the Z direction (first direction) indicates the direction in which the optical axis of the light source 33 extends.

[0013] 3 is a schematic diagram showing a cross section of a liquid crystal panel 2. The liquid crystal panel 2 includes a first substrate 5, a second substrate 6, a liquid crystal layer 32, and a sealant 31. That is, the liquid crystal panel 2 includes the liquid crystal layer 32 between the first substrate 5 and the second substrate 6, the periphery of which is sealed with the sealant 31.

[0014] The liquid crystal layer 32 modulates light passing through the liquid crystal layer 32 according to the state of the electric field. Positive nematic liquid crystal is used as the liquid crystal molecules 35, but other liquid crystals having a similar effect may also be used.

[0015] 3 , the first substrate 5 is provided with a drive electrode 10a extending in the X direction and wirings 11c, 11f, 11i, and 11l extending in the Y direction. In an effective area AA of the first substrate 5, the drive electrode 10a is covered with an alignment film 36. The second substrate 6 is provided with drive electrodes 13a and 13b extending in the Y direction. In the effective area AA of the second substrate 6, the drive electrodes 13a and 13b are covered with an alignment film 37.

[0016] Fig. 4 is a schematic view of the first substrate as viewed from the Z direction, Fig. 5 is a schematic view of the second substrate as viewed from the Z direction, and Fig. 6 is a schematic view of the liquid crystal panel as viewed from the Z direction.

[0017] 4 , first substrate 5 is provided with connection terminal groups 16 and 17. Connection terminal group 16 is arranged at the end on both the X1 and Y1 sides, and connection terminal group 17 is arranged at the end on both the X2 and Y1 sides. Connection terminal group 16 includes terminals 161, 162, 163, 164, 165, and 166. Connection terminal group 17 includes terminals 171, 172, 173, 174, 175, and 176.

[0018] The first substrate 5 is provided with a driving electrode 10. The driving electrode 10 extends in the X direction. The driving electrode 10 includes driving electrodes 10a, 10b, 10c, 10d, 10e, and 10f. The driving electrodes 10a, 10b, 10c, 10d, 10e, and 10f are arranged in this order from the Y2 side to the Y1 side. The driving electrode 10a is connected to a terminal 163 via a wiring 11c. The driving electrode 10b is connected to a terminal 173 via a wiring 11i. The driving electrode 10c is connected to a terminal 162 via a wiring 11b. The driving electrode 10d is connected to a terminal 172 via a wiring 11h. The driving electrode 10e is connected to a terminal 161 via a wiring 11a. The driving electrode 10f is connected to a terminal 171 via a wiring 11g.

[0019] An end of the wiring 11f is provided with a conductive portion 41, an end of the wiring 11e is provided with a conductive portion 42, and an end of the wiring 11d is provided with a conductive portion 43. In addition, an end of the wiring 11j is provided with a conductive portion 44, an end of the wiring 11k is provided with a conductive portion 45, and an end of the wiring 11l is provided with a conductive portion 46.

[0020] As shown in FIG. 5 , drive electrodes 13 are provided on the second substrate 6. The drive electrodes 13 extend in the Y direction. The drive electrodes 13 include drive electrodes 13a, 13b, 13c, 13d, 13e, and 13f. The drive electrodes 13a and 13b are arranged alternately in the X direction. The drive electrodes 13a and 13b are arranged in the same row along the X direction. The drive electrodes 13c and 13d are arranged alternately in the X direction. The drive electrodes 13c and 13d are arranged in the same row along the X direction. The drive electrodes 13c and 13d are adjacent to the drive electrodes 13a and 13b on the Y1 side. The drive electrodes 13e and 13f are arranged alternately in the X direction. The drive electrodes 13e and 13f are arranged in the same row along the X direction. The driving electrodes 13e and 13f are adjacent to the driving electrodes 13c and 13d on the Y1 side.

[0021] The driving electrode 13a is connected to the wiring 12a. The driving electrode 13b is connected to the wiring 12d. The driving electrode 13c is connected to the wiring 12b. The driving electrode 13d is connected to the wiring 12e. The driving electrode 13e is connected to the wiring 12c. The driving electrode 13f is connected to the wiring 12f.

[0022] A conductive portion 41A is provided at the end of wiring 12c, a conductive portion 42A is provided at the end of wiring 12b, and a conductive portion 43A is provided at the end of wiring 12a. In addition, a conductive portion 44A is provided at the end of wiring 12d, a conductive portion 45A is provided at the end of wiring 12e, and a conductive portion 46A is provided at the end of wiring 12f.

[0023] Here, conductive portion 41 and conductive portion 41A are electrically connected via a conductive pillar not shown, conductive portion 42 and conductive portion 42A are electrically connected via a conductive pillar not shown, conductive portion 43 and conductive portion 43A are electrically connected via a conductive pillar not shown, conductive portion 44 and conductive portion 44A are electrically connected via a conductive pillar not shown, conductive portion 45 and conductive portion 45A are electrically connected via a conductive pillar not shown, and conductive portion 46 and conductive portion 46A are electrically connected via a conductive pillar not shown.

[0024] 6, in the liquid crystal panel 2, the effective area AA is divided into three partial areas, a first area A1, a second area A2, and a third area A3, when viewed from the Z direction. That is, when viewed from the Z direction, the driving electrodes 10 and 13 intersect to form the effective area AA, but the effective area AA is divided into three.

[0025] When viewed from the Z direction, the first region A1 is a partial region where the drive electrodes 10a, 10b intersect with the drive electrodes 13a, 13b. The second region A2 is a partial region where the drive electrodes 10c, 10d intersect with the drive electrodes 13c, 13d. The third region A3 is a partial region where the drive electrodes 10e, 10f intersect with the drive electrodes 13e, 13f. When viewed from the Z direction, each of the three partial regions is a rectangle that is longer in the X direction. The three rectangles have approximately the same area. The three regions are aligned in the Y direction. Specifically, the second region A2 is adjacent to the first region A1 on the Y1 side. The third region A3 is adjacent to the second region A2 on the Y1 side. The combined effective area AA of the three partial regions has a substantially square shape when viewed from the Z direction. As described above, in the first embodiment, in the liquid crystal panel 2, one effective area AA is divided into three partial regions along the Y direction.

[0026] As described above, the liquid crystal panel 2 has the first substrate 5 and the second substrate 6 overlapping in the Z direction (stacking direction, light irradiation direction), and the plurality of drive electrodes 10 on the first substrate 5 and the plurality of drive electrodes 13 on the second substrate 6 intersect as viewed from the Z direction. The liquid crystal panel 2 configured in this manner can control the alignment direction of the liquid crystal molecules 35 in the liquid crystal layer 32 by supplying 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 where the alignment direction of the liquid crystal molecules 35 can be controlled is the aforementioned effective area AA (see FIG. 3 ). By changing the refractive index distribution of the liquid crystal layer 32 in this effective area AA, the degree of diffusion of light passing through the effective area AA of the liquid crystal panel 2 can be controlled. The region outside the effective area AA, where the liquid crystal layer 32 is sealed with the sealant 31, is the peripheral area GA (see FIG. 3 ).

[0027] In this embodiment, the alignment direction of the liquid crystal molecules 35 can be controlled individually in each of the first region A1, the second region A2, and the third region A3. For example, when a voltage is supplied only to the drive electrodes in the first region A1 (the drive electrodes 10a, 10b and the drive electrodes 13a, 13b in each of the four liquid crystal panels 2), the alignment direction of the liquid crystal molecules 35 in the liquid crystal layer 32 in the first region A1 is controlled, but the alignment direction of the liquid crystal molecules 35 in the liquid crystal layer 32 in the second region A2 and the third region A3 is not controlled. In other words, the multiple partial regions each have the drive electrodes 10a, 10b and the drive electrodes 13a, 13b that are provided so that the voltage supplied thereto can be individually controlled.

[0028] 6 , when a voltage is supplied to drive electrode 10a via terminal 163, a voltage is supplied to drive electrode 10b via terminal 173, a voltage is supplied to drive electrode 13a via terminal 164, and a voltage is supplied to drive electrode 13b via terminal 174, the alignment direction of the liquid crystal molecules 35 of the liquid crystal layer 32 in the first region A1 is controlled. Also, for example, when a voltage is supplied only to the drive electrodes in the second region A2 (drive electrodes 10c, 10d and drive electrodes 13c, 13d in each of the four liquid crystal panels 2), the alignment direction of the liquid crystal molecules 35 of the liquid crystal layer 32 in the second region A2 is controlled, but the alignment direction of the liquid crystal molecules 35 of the liquid crystal layer 32 in the first region A1 and the third region A3 is not controlled.

[0029] For example, when a voltage is supplied only to the drive electrodes in the third region A3 (drive electrodes 10e, 10f and drive electrodes 13e, 13f in each of the four liquid crystal panels 2), the alignment direction of the liquid crystal molecules 35 in the liquid crystal layer 32 in the third region A3 is controlled, but the alignment direction of the liquid crystal molecules 35 in the liquid crystal layer 32 in the first region A1 and the second region A2 is not controlled.

[0030] Furthermore, by repeating the cycle of supplying a voltage to the drive electrodes of the first region A1, then supplying a voltage to the drive electrodes of the second region A2, then supplying a voltage to the drive electrodes of the third region A3, and then again supplying a voltage to the drive electrodes of the first region A1, it is possible to produce a fluctuation in light distribution that harmonizes regularity and irregularity. In this way, each of the multiple partial regions is configured to be able to switch between translucency and light diffusion. Note that, in the fluctuation of light distribution, 1 / f fluctuation can be realized when the amplitude of the oscillation is inversely proportional to a frequency f in a finite range greater than 0. Light distribution controlled by 1 / f fluctuation is expected to have a calming and comfortable effect on people.

[0031] 7A and 7B are diagrams showing the alignment direction of the alignment film of the first substrate as viewed from the Z direction, respectively, and Fig. 7B is a diagram showing the alignment direction of the alignment film of the second substrate as viewed from the Z direction.

[0032] As shown in Figures 7A and 7B, the orientation direction of the orientation film 36 (see Figure 3) of the first substrate 5 and the orientation direction of the orientation film 37 (see Figure 3) of the second substrate 6 are perpendicular (intersecting) to each other in a planar view from the Z direction.

[0033] Specifically, in Fig. 7A, the alignment direction of the alignment film 18 of the first substrate 5 is indicated by a thick solid arrow. The alignment direction of the alignment film 36 is the Y direction. Also in Fig. 7A, the extension direction of the drive electrodes 10 is indicated by a dashed arrow. The extension direction of the drive electrodes 10 is the X direction. The alignment direction of the alignment film 36 is perpendicular to (intersects) the extension direction of the drive electrodes 10.

[0034] In FIG. 7B , the orientation direction of the orientation film 37 of the second substrate 6 is indicated by a thick solid arrow. The orientation direction of the orientation film 37 is the X direction. Also in FIG. 7B , the extension direction of the drive electrodes 13 is indicated by a dashed arrow. The extension direction of the drive electrodes 13 is the Y direction. The orientation direction of the orientation film 37 is perpendicular (intersecting) to the extension direction of the drive electrodes 13. In this way, the orientation direction of the orientation film 36 of the first substrate 5 and the orientation direction of the orientation film 37 of the second substrate 6 are perpendicular (intersecting) to each other in a plan view seen from the Z direction. As a result, the orientation of the liquid crystal molecules 35 of the liquid crystal layer 32 gradually changes from the X direction to the Y direction (or from the Y direction to the X 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 panel 2, the p-polarized light component (hereinafter referred to as p-wave) on the first substrate 5 side changes to an s-polarized light component (hereinafter referred to as s-wave) as it moves toward the second substrate 6 side, and the s-wave on the first substrate 5 side changes to a p-wave as it moves toward the second substrate 6 side. This rotation of the polarized light component is called optical rotation.

[0035] 8 and 9 are conceptual diagrams showing changes in the state of light passing through the panel unit according to the first embodiment. As described above, the effective area AA of the panel unit 100 is divided into three partial areas. Below, the changes in the state of light passing through the first partial area A1 will be described using the first partial area A1 as an example.

[0036] 8 illustrates a state in which no potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2. Specifically, in the first region A1, there is no potential difference between drive electrodes 10a and 10b on the first substrate 5, and there is no potential difference between drive electrodes 13a and 13b on the second substrate 6. In this case, only optical rotation occurs in each liquid crystal panel 2, and none of the polarization components are diffused. That is, as shown in FIG. 8 , light (p-wave) emitted from the light source 33 becomes an s-wave in the first liquid crystal panel 21 as it travels from the first substrate 5 to the second substrate 6. Thereafter, the light is rotated from an s-wave to a p-wave in the second liquid crystal panel 22, rotated from a p-wave to an s-wave in the third liquid crystal panel 23, and rotated from an s-wave to a p-wave in the fourth liquid crystal panel 24, and the p-wave is then emitted from the panel unit 100. In this way, when no potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2, light incident on the panel unit 100 passes through without being diffused and is emitted from the panel unit 100.

[0037] 9 shows a state in which a potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2. Specifically, there is a potential difference between drive electrodes 10a and 10b on the first substrate 5 side, and there is a potential difference between drive electrodes 13a and 13b on the second substrate 6 side. In FIG. 9, dotted hatching is used to indicate diffused areas.

[0038] Here, because a potential difference is generated between drive electrodes 10a and 10b on the first substrate 5 side of first liquid crystal panel 21, liquid crystal molecules are oriented in an arc shape between the electrodes, thereby forming a refractive index distribution along the Y direction in liquid crystal layer 32. In this state, when light from light source 33 passes through the first substrate 5 side of first liquid crystal panel 21, the refractive index distribution acts on the polarized light component parallel to the Y direction (p-wave in FIG. 9 ), causing the p-wave to diffuse in the Y direction on the first substrate 5 side. In FIG. 9 , this is referred to as "p-diffusion," and the words "p-diffusion" are surrounded by dotted hatching.

[0039] Furthermore, because 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 panel 21, a refractive index distribution is formed in the X direction on the second substrate 6 side, which causes the s-waves to diffuse in the X direction on the second substrate 6 side. In other words, the polarized light components that have been optically rotated from p-waves to s-waves while passing through the liquid crystal layer 32 of the first liquid crystal panel 21 are now diffused in the X direction as well. In Figure 9, this is referred to as "s-diffusion," and the words "s-diffusion" are surrounded by dotted hatching.

[0040] On the other hand, when the s-wave enters the first liquid crystal panel 21, it rotates while passing through the liquid crystal layer 32, but becomes a polarization component that intersects with both refractive index distributions, so it only rotates without being diffused and becomes a p-wave, which transmits (passes through) the liquid crystal layer 32 of the first liquid crystal panel 21.

[0041] The p-waves incident on the second liquid crystal panel 22 are diffused on the first substrate 5 side, and are optically rotated from p-waves to s-waves while passing through the liquid crystal layer 32 of the second liquid crystal panel 22, and the s-waves are diffused on the second substrate 6 side. On the other hand, the s-waves incident on the second liquid crystal panel 22 are only optically rotated without being diffused, becoming p-waves, and pass through the liquid crystal layer 32 of the second liquid crystal panel 22.

[0042] The p-waves incident on the third liquid crystal panel 23 are diffused on the first substrate 5 side, and are optically rotated from p-waves to s-waves while passing through the liquid crystal layer 32 of the second liquid crystal panel 22, and the s-waves are diffused on the second substrate 6 side. On the other hand, the s-waves incident on the third liquid crystal panel 23 are only optically rotated without being diffused, becoming p-waves, and pass through the liquid crystal layer 32 of the third liquid crystal panel 23.

[0043] The p-waves incident on the fourth liquid crystal panel 24 are diffused on the first substrate 5 side, and are optically rotated from p-waves to s-waves while passing through the liquid crystal layer 32 of the fourth liquid crystal panel 24, and the s-waves are diffused on the second substrate 6 side. On the other hand, the s-waves incident on the fourth liquid crystal panel 24 are only optically rotated without being diffused, becoming p-waves and passing through the liquid crystal layer 32 of the fourth liquid crystal panel 24. In this way, when a potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2, the light incident on the panel unit 100 is diffused and emitted from the panel unit 100.

[0044] Next, a block diagram of the lighting device will be described. Fig. 10 is a block diagram of the lighting device according to the first embodiment. As shown in Fig. 10, the lighting device 1 according to the first embodiment includes an electrode driving circuit 112, a memory circuit 113, and a processing circuit 114 as a control block for controlling the panel unit 100 described above. The processing circuit 114 is configured with a microcomputer for executing light distribution control and dimming control of the lighting device 1.

[0045] The electrode driving circuit 112 supplies voltage to each of the driving electrodes 10, 13 of each liquid crystal panel 2 of the panel unit 100 based on the processing result in the processing circuit 114. The processing in the processing circuit 114 will be described later.

[0046] The storage circuitry 113 includes, for example, an internal memory implemented in a microcomputer that constitutes the processing circuitry 114. In a storage area of ​​the storage circuitry 113, intermediate data of processing in the processing circuitry 114 is temporarily stored.

[0047] The memory circuit 113 also includes a setting circuit 1131. The setting circuit 1131 sets various setting items such as the order in which voltages are supplied to the partial areas of the effective area AA, whether fluctuation control is enabled or disabled, and the fluctuation width that defines the range of change in the light distribution value due to fluctuation control.

[0048] The order of voltage supply will be briefly explained. The partial areas of the effective area AA are, for example, the first area A1, the second area A2, and the third area A3 described above. When supplying voltage, for example, voltage is supplied to the first area A1 followed by the second area A2, then to the second area A2 followed by the third area A3, and then again to the first area A1, repeating this cycle. The order of voltage supply is preset in the setting circuit 1131, and this order is stored in the memory circuit 113. That is, the setting circuit 1131 determines which of the multiple partial areas are to be transparent and which are to be diffused. The setting circuit 1131 may be, for example, a DIP switch (Dual In-line Package switch) capable of setting each setting item. In this case, the setting circuit 1131 may be configured to include multiple two-state switch circuits, for example, "0" and "1."

[0049] Fig. 11 is a schematic diagram showing four liquid crystal panels stacked in the Z direction, and Fig. 12 is a schematic diagram showing how an image projected by a panel unit changes over time.

[0050] 2, the panel unit 100 is formed by stacking a first liquid crystal panel 21, a second liquid crystal panel 22, a third liquid crystal panel 23, and a fourth liquid crystal panel 24 in the Z direction. As shown in Fig. 11, the first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 have the same structure. Specifically, the first liquid crystal panel 21 to the fourth liquid crystal panel 24 have the same configuration as the liquid crystal panel 2 in which the effective area AA is divided into three partial areas, a first area A1, a second area A2, and a third area A3, as shown in Fig. 6.

[0051] Then, the first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 are stacked in this order from the Z2 side toward the Z1 side. Therefore, the first regions A1 of the first liquid crystal panel 21, the second liquid crystal panel 22, the third liquid crystal panel 23, and the fourth liquid crystal panel 24 overlap when viewed from the Z direction, and the second regions A2 and the third regions A3 also overlap when viewed from the Z direction. Note that, in a plan view of the panel unit 100 viewed from the Z direction, as shown at the right end of FIG. 11 , the first region A1 is located on the Y2 side, the third region A3 is located on the Y1 side, and the second region A2 is located toward the center in the Y direction.

[0052] Next, the movement of the projection image by the panel unit will be described with reference to FIG.

[0053] First, in the first step C1 shown on the left side of Fig. 12, a voltage is supplied to all of the first region A1, second region A2, and third region A3 in the panel unit 100. That is, a potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2 in all of the first region A1, second region A2, and third region A3. Therefore, in the first step C1, all of the first region A1, second region A2, and third region A3 in the panel unit 100 become diffusion sections indicated by normal hatching, as shown in Fig. 12. Here, the diffusion sections refer to the regions that emit diffused light, as described in Fig. 9.

[0054] Therefore, in the first step C1, the light emitted from the light source 33 enters the panel unit 100, undergoes optical rotation and diffusion within the panel unit 100, and is emitted as diffused light 420 from all of the first area A1, the second area A2, and the third area A3. Therefore, the entire irradiation image 400 becomes the diffused light irradiation area B1.

[0055] Next, in the second step C2 shown in the center of Fig. 12, a voltage is supplied only to the second region A2 in the panel unit 100. That is, a potential difference occurs between adjacent drive electrodes in each liquid crystal panel 2 only in the second region A2. Therefore, in the second step C2, the second region A2 in the panel unit 100 becomes a diffusion portion indicated by normal hatching as shown in Fig. 12, and the first region A1 and the third region A3 become transmissive portions that transmit light without being supplied with voltage.

[0056] Therefore, in the second step C2, the light emitted from the light source 33 enters the panel unit 100, undergoes optical rotation and diffusion in the second region A2, and is emitted from the panel unit 100 as diffused light 420. Furthermore, the light that passes through the first region A1 and the third region A3 is transmitted without being diffused. Therefore, of the irradiation image 400, both the left and right sides become transmitted light irradiation areas B2, and the left and right center portion becomes diffused light irradiation area B1.

[0057] Next, in the third step C3 shown on the right side of Fig. 12, a voltage is supplied to the first region A1 and the third region A3 of the panel unit 100. That is, in the first region A1 and the third region A3, a potential difference occurs between adjacent drive electrodes of each liquid crystal panel 2. Therefore, in the third step C3, the first region A1 and the third region A3 of the panel unit 100 become diffusion regions indicated by normal hatching, as shown in Fig. 12, and the second region A2 becomes a transmissive region to which no voltage is supplied.

[0058] Therefore, in the third step C3, the light emitted from the light source 33 enters the panel unit 100, undergoes optical rotation and diffusion in the first region A1 and the third region A3, and then exits the panel unit 100 as diffused light 420. Furthermore, the light that passes through the second region A2 is only optically rotated and transmits without being diffused. Therefore, the left and right sides of the irradiation image 400 become diffused light irradiation areas B1, and the left and right central portion becomes transmitted light irradiation area B2.

[0059] After the third step C3, the process returns to the first step C1, and then the process moves again from the second step C2 to the third step C3. In this way, in the first embodiment, the cycle of the first step C1, the second step C2, and the third step C3 is repeated.

[0060] As described above, the lighting device 1 according to the first embodiment includes the light source 33 and the panel unit 100. The effective area AA of at least one of the plurality of liquid crystal panels 2 includes a first area A1 to a third area A3, which are divided into a plurality of partial areas when viewed from the Z direction. Each of the plurality of partial areas is provided so as to be switchable between transmitting light and diffusing light.

[0061] As described above, the lighting control device according to Patent Document 1 includes a dimming signal generation unit that issues dimming operation instructions for parameters including dimming output, flickering lighting cycle, and color tone.

[0062] In contrast, in the first embodiment, the effective area AA includes a plurality of divided partial areas, and each of the plurality of partial areas has driving electrodes 10a, 10b, 10c, 10d, 10e, and 10f and driving electrodes 13a, 13b, 13c, 13d, 13e, and 13f, to which the voltage supplied can be individually controlled.

[0063] Specifically, which of the plurality of partial regions is to transmit light and which is to diffuse light is set in the setting circuit 1131. By supplying a voltage to the drive electrodes 10, 13 for each partial region, the refractive index distribution of the liquid crystal layer 32 changes, and the plurality of partial regions are switched between transmitting light and diffusing light according to the voltage of the drive electrodes.

[0064] Therefore, the lighting device 1 according to the first embodiment can achieve dynamic light distribution control by fluctuation with a simpler configuration than that of Patent Document 1.

[0065] In the first embodiment, the first to third regions A1 to A3, which are the plurality of partial regions, are arranged along the Y direction.

[0066] Therefore, compared to an arrangement in which a plurality of partial regions are arranged in both the X direction and the Y direction, for example, this arrangement is simpler, and as a result, dynamic light distribution control by fluctuation can be achieved with a simpler configuration.

[0067] [Second embodiment] Next, a second embodiment will be described. Fig. 13 is a schematic diagram showing a liquid crystal panel according to the second embodiment. Fig. 14 is a schematic diagram showing a first substrate viewed from the Z direction. Fig. 15 is a schematic diagram showing a second substrate viewed from the Z direction. Fig. 16 is a schematic diagram showing four liquid crystal panels stacked in the Z direction. Fig. 17 is a schematic diagram showing how an image projected by a panel unit changes over time.

[0068] In the first embodiment, the liquid crystal panel 2 divides one effective area AA into three partial areas along the Y direction. In contrast, in the second embodiment, the liquid crystal panel 2A divides one effective area AA into five partial areas along the Y direction. This will be explained in detail below.

[0069] 13, in the liquid crystal panel 2A according to the second embodiment, the effective area AA is divided into five partial areas, a first area A1, a second area A2, a third area A3, a fourth area A4, and a fifth area A5, when viewed from the Z direction. Specifically, the first area A1, the second area A2, the third area A3, the fourth area A4, and the fifth area A5 are arranged in this order from the Y2 side to the Y1 side.

[0070] As shown in FIG. 14 , the first substrate 5A includes drive electrodes 10a and 10b extending in the Y direction. For reference, the first region A1 is indicated by a two-dot chain line in FIG. 14 . The drive electrodes 10a and 10b are alternately arranged at intervals in the X direction. Drive electrodes 10a and 10b are provided corresponding to the first region A1 and are alternately arranged in the X direction. The Y-direction length of the drive electrodes 10a and 10b is approximately the same as the Y-direction length of the first region A1. Furthermore, the X-direction length of the drive electrodes 10a and 10b corresponding to the first region A1 is approximately the same as the X-direction length of the first region A1.

[0071] The second region A2 to the fifth region A5 also have the same configuration as the first region A1. That is, for example, the second region A2 also has drive electrodes 10a and drive electrodes 10b arranged alternately in the X direction, corresponding to the second region A2 shown in FIG. 13 . The Y-direction length of the drive electrodes 10a and drive electrodes 10b is approximately the same as the Y-direction length of the second region A2. The X-direction length of the drive electrodes 10a and drive electrodes 10b corresponding to the second region A2 is also approximately the same as the X-direction length of the second region A2.

[0072] In Figure 15, for reference, the first region A1 is indicated by a two-dot chain line. In the second substrate 6A shown in Figure 15, four drive electrodes 13a, 13b, 13a, 13b extending in the X direction are provided corresponding to the first region A1. Each of the drive electrodes 13a, 13b extends in the X direction. The drive electrodes 13a, 13b are aligned along the Y direction at intervals. That is, the drive electrodes 13a, 13b are alternately aligned along the Y direction at intervals, and the first region A1 includes four drive electrodes aligned adjacent to each other in the Y direction. In the second region A2 to the fifth region A5, four drive electrodes 13a, 13b, 13a, 13b extending in the X direction are also aligned along the Y direction.

[0073] As a result, in each of the first region A1 to the fifth region A5, the driving electrodes 10a and 10b and the driving electrodes 13a and 13b are orthogonal (intersect) with each other when viewed from the Z direction.

[0074] 16, the first liquid crystal panel 21A, the second liquid crystal panel 22A, the third liquid crystal panel 23A, and the fourth liquid crystal panel 24A are stacked in this order from the Z2 side to the Z1 side to form the panel unit 100A. Therefore, the first regions A1 of the first liquid crystal panel 21A, the second liquid crystal panel 22A, the third liquid crystal panel 23A, and the fourth liquid crystal panel 24A overlap when viewed from the Z direction, and the second regions A2 to the fifth regions A5 also overlap when viewed from the Z direction.

[0075] Next, the movement of the projection image by the panel unit will be described with reference to FIG.

[0076] 17, voltage is supplied to all of the first area A1, second area A2, third area A3, fourth area A4, and fifth area A5 of the panel unit 100A. Therefore, in the first step C11, all of the first area A1 to fifth area A5 of the panel unit 100A become diffusion areas.

[0077] Therefore, in the first step C11, the light emitted from the light source 33 enters the panel unit 100A, undergoes optical rotation and diffusion within the panel unit 100, and is emitted as diffused light 420 from all of the first area A1 to the fifth area A5. Therefore, the entire irradiation image 400 becomes the diffused light irradiation area B1.

[0078] Next, in a second step C12, a voltage is supplied to the areas of the panel unit 100A other than the second area A2. Therefore, the second area A2 becomes a transmissive area, and the first area A1 and the third area A3 to the fifth area A5 become diffusion areas.

[0079] Therefore, in the second step C12, the light emitted from the light source 33 enters the panel unit 100, undergoes optical rotation and diffusion in the areas other than the second area A2, and is emitted from the panel unit 100 as diffused light 420. Furthermore, the light that passes through the second area A2 is only optically rotated and is emitted from the panel unit 100 without being diffused. Therefore, in the irradiation image 400, the portion corresponding to the second area A2 becomes the transmitted light irradiation area B2, and the portion corresponding to the area other than the second area A2 becomes the diffused light irradiation area B1.

[0080] Similarly, in the third step C13, the fourth region A4 becomes the transmission portion, and the region other than the fourth region A4 becomes the diffusion portion. Therefore, in the irradiation image 400, the portion corresponding to the fourth region A4 becomes the transmitted light irradiation area B2, and the portion other than the fourth region A4 becomes the diffusion light irradiation area B1.

[0081] In the fourth step C14, the first region A1 and the fifth region A5 become the transmission portion, and the region other than the first region A1 and the fifth region A5 becomes the diffusion portion. Therefore, in the irradiation image 400, the portion corresponding to the first region A1 and the fifth region A5 becomes the transmitted light irradiation area B2, and the portion corresponding to the region other than the first region A1 and the fifth region A5 becomes the diffusion light irradiation area B1.

[0082] In the fifth step C15, the third region A3 becomes the transmission portion, and the region other than the third region A3 becomes the diffusion portion. Therefore, in the irradiation image 400, the portion corresponding to the third region A3 becomes the transmitted light irradiation area B2, and the portion other than the third region A3 becomes the diffusion light irradiation area B1.

[0083] After the fifth step C15, the process returns to the first step C11, and then proceeds again to the second step C12, the third step C13, the fourth step C14, and the fifth step C15. In this way, in the second embodiment, the cycle from the first step C1 to the fifth step C15 is repeated.

[0084] As described above, in the lighting device according to the second embodiment, the liquid crystal panel 2A divides one effective area AA into five partial areas along the Y direction, and each of the five partial areas is provided so as to be switchable between transmitting light and diffusing light. Specifically, by supplying a voltage to the drive electrodes 10, 13 for each partial area, the refractive index distribution of the liquid crystal layer 32 changes, and light passing through the liquid crystal panel 2 is diffused independently for each partial area.

[0085] Therefore, similar to the first embodiment, the lighting device according to the second embodiment can achieve dynamic light distribution control by fluctuation with a simpler configuration than the lighting device according to Patent Document 1.

[0086] [Third Embodiment] Next, a third embodiment will be described. Fig. 18 is a schematic diagram showing a liquid crystal panel according to the third embodiment. Fig. 19 is a schematic diagram of a first substrate viewed from the Z direction. Fig. 20 is a schematic diagram of a second substrate viewed from the Z direction.

[0087] In the liquid crystal panel 2A according to the second embodiment, one effective area AA is divided into five partial areas along the Y direction. In contrast, in the third embodiment, each of the first area A1 to the fifth area A5 of the liquid crystal panel 2A according to the second embodiment is divided into two areas. This will be explained in detail below.

[0088] As shown in FIG. 18 , the liquid crystal panel 2B according to the third embodiment has an effective area AA divided into ten regions when viewed from the Z direction. Specifically, the regions corresponding to the first region A1 to the fifth region A5 of the liquid crystal panel 2A according to the second embodiment are divided into two regions, a sixth region A11 and a seventh region A12. When viewed from the Z direction, the sixth region A11 and the seventh region A12 each have a right-angled triangular shape. The sixth region A11 and the seventh region A12 are congruent. The sixth region A11 has a hypotenuse A11a, an opposite side A11b, and an adjacent side A11c. The opposite side A11b extends in the Y direction. The adjacent side A11c extends in the X direction. The crossing angle between the opposite side A11b and the adjacent side A11c is 90 degrees. The hypotenuse A11a connects the opposite side A11b and the adjacent side A11c. The sixth region A11 has a length in the Y direction that decreases toward the X2 side.

[0089] The seventh region A12 has a hypotenuse A12a, an opposite side A12b, and an adjacent side A12c. The opposite side A12b extends in the Y direction. The adjacent side A12c extends in the X direction. The crossing angle between the opposite side A12b and the adjacent side A12c is 90 degrees. The hypotenuse A12a connects the opposite side A12b and the adjacent side A12c. The length of the seventh region A12 in the Y direction decreases toward the X1 side.

[0090] The sixth region A11 and the seventh region A12 are congruent right triangles with the same hypotenuse A11a and hypotenuse A12a. Therefore, when the sixth region A11 and the seventh region A12 are joined together with the hypotenuse A11a and the hypotenuse A12a aligned, the sixth region A11 and the seventh region A12 form a rectangle that is long in the X direction.

[0091] As shown in FIG. 19 , the first substrate 5B includes drive electrodes 10a and 10b extending in the Y direction. For reference, the sixth region A11 and the seventh region A12 are indicated by dashed double-dashed lines in FIG. 19 . The drive electrodes 10a and 10b are alternately arranged at intervals in the X direction. The drive electrodes 10a and 10b are arranged alternately in the X direction in correspondence with the sixth region A11. The lengths of the drive electrodes 10a and 10b gradually increase in the Y direction toward the X1 side. Specifically, in the sixth region A11, the drive electrode 10b adjacent to the drive electrode 10a located at the X1 side of the drive electrode 10a closest to the X2 end is longer in the Y direction than the drive electrode 10a located at the X1 side of the drive electrode 10a. Furthermore, the drive electrode 10b adjacent to the drive electrode 10a on the X1 side (i.e., the fourth drive electrode from the X2 end) is longer in the Y direction than the third drive electrode 10a from the X2 end toward the X1 side. In the seventh region A12, the driving electrodes 10a and 10b are also alternately arranged at intervals in the X direction. In the seventh region A12, the lengths of the driving electrodes 10a and 10b in the Y direction gradually decrease toward the X1 side.

[0092] As shown in FIG. 20 , the second substrate 6B includes drive electrodes 13a and 13b extending in the X direction. For reference, the sixth region A11 and the seventh region A12 are indicated by dashed double-dashed lines in FIG. 20 . The drive electrodes 13a and 13b are spaced apart in the Y direction. That is, a set of drive electrodes 13a, 13b, 13b, and 13a is repeatedly arranged from the Y2 end toward the Y1 end. Specifically, the drive electrode located at the Y2 end is drive electrode 13a, and drive electrode 13a includes drive electrode 13a1 on the X2 side and drive electrode 13a2 on the X1 side. Drive electrodes 13a1 and 13a2 are arranged on the same straight line extending in the X direction. The length of drive electrode 13a1 in the X direction is shorter than that of drive electrode 13a2. The second drive electrode from the Y2 end is drive electrode 13b, which includes drive electrode 13b1 on the X2 side and drive electrode 13b2 on the X1 side. Drive electrodes 13b1 and 13b2 are arranged on the same straight line extending in the X direction. The X-direction length of drive electrode 13b1 is longer than drive electrode 13a1 and shorter than drive electrode 13b2. The third drive electrode from the Y2 end is drive electrode 13b, which includes drive electrode 13b1 on the X1 side and drive electrode 13b2 on the X2 side. The fourth drive electrode from the Y2 end is drive electrode 13a, which includes drive electrode 13a2 on the X2 side and drive electrode 13a1 on the X1 side. In the sixth region A11, drive electrodes 13a2, 13b2, 13b1, and 13a1 are arranged from the Y2 side. The height of the drive electrodes arranged in the sixth region A11 in the X direction gradually decreases from the Y2 side to the Y1 side. In the seventh region A12, drive electrodes 13a1, 13b1, 13b2, and 13a2 are arranged from the Y2 side. The height of the drive electrodes arranged in the seventh region A12 in the X direction gradually increases from the Y2 side to the Y1 side.

[0093] As described above, in the lighting device according to the third embodiment, the sixth region A11 and the seventh region A12, which are the plurality of partial regions, are arranged along the Y direction.

[0094] Therefore, compared to an arrangement in which a plurality of partial regions are arranged in both the X direction and the Y direction, for example, this arrangement is simpler, and as a result, dynamic light distribution control by fluctuation can be achieved with a simpler configuration.

[0095] Fourth Embodiment Next, a fourth embodiment will be described. Fig. 21 is a schematic diagram showing a panel unit according to the fourth embodiment.

[0096] In the panel unit 100C according to the fourth embodiment, the effective area AA is divided into nine partial areas when viewed from the Z direction. Specifically, the first areas A1 described in the first embodiment are arranged in three rows in the Y direction and three columns in the X direction. When viewed from the Z direction, each first area A1 is square, and the entire effective area AA, including all nine of them, is also square.

[0097] Each first area A1 includes four liquid crystal panels 2C stacked in the Z direction. Each liquid crystal panel 2C includes a first substrate 5C and a second substrate 6C. In the first substrate 5C, for example, the drive electrodes 10 shown in FIG. 4 extend in the X direction. In the second substrate 6C, for example, the drive electrodes 13 shown in FIG. 5 extend in the Y direction. Therefore, the liquid crystal panel 2C has drive electrodes 10 and 13 that intersect with each other. In this embodiment, a voltage is supplied individually to each of the nine first areas A1, making it possible to individually control the alignment direction of the liquid crystal molecules 35 in each of the nine first areas A1.

[0098] As described above, in the lighting device according to the fourth embodiment, the liquid crystal panel 2C divides one effective area AA into nine partial areas along the X and Y directions, and drives each of the partial areas independently.

[0099] Therefore, similar to the first embodiment, the lighting device according to the fourth embodiment can achieve dynamic light distribution control by fluctuation with a simpler configuration than the lighting device according to Patent Document 1.

[0100] Fifth Embodiment Next, a fifth embodiment will be described. Fig. 22 is a schematic diagram showing a panel unit according to the fifth embodiment.

[0101] In the panel unit 100D according to the fifth embodiment, the effective area AA is divided into 13 partial areas when viewed from the Z direction. In the fifth embodiment, the effective area AA is arranged by combining a first area A1, a second area A2, and a third area A3.

[0102] Specifically, as shown in Figure 22, first regions A1 each having a right-angled triangle shape when viewed from the Z direction are arranged at the Y2-side end and the Y1-side end, respectively. Second regions A2 and third regions A3 are alternately arranged along the Y direction between these two first regions A1. The second regions A2 and third regions A3 are each an isosceles triangle when viewed from the Z direction. The length of the second region A2 in the Y direction decreases toward the X1 side. The length of the third region A3 in the Y direction decreases toward the X2 side.

[0103] The panel unit 100D is configured by stacking four liquid crystal panels 2D. The liquid crystal panel 2D includes a first substrate 5D and a second substrate 6D. On the first substrate 5D, for example, the drive electrodes 10 shown in FIG. 4 extend in the X direction. On the second substrate 6D, for example, the drive electrodes 13 shown in FIG. 5 extend in the Y direction. Therefore, the liquid crystal panel 2D has drive electrodes 10 and 13 that intersect with each other.

[0104] As described above, in the lighting device according to the fifth embodiment, the first region A1, the second region A2, and the third region A3, which are the plurality of partial regions, are arranged along the Y direction.

[0105] Therefore, compared to an arrangement in which a plurality of partial regions are arranged in both the X direction and the Y direction, for example, this arrangement is simpler, and as a result, dynamic light distribution control by fluctuation can be achieved with a simpler configuration.

[0106] Sixth Embodiment Next, a sixth embodiment will be described. Fig. 23 is a schematic diagram showing a panel unit according to the sixth embodiment.

[0107] In the second embodiment, as shown in Fig. 13, the effective area AA is divided into five rectangular partial areas that are long in the X direction, and the divided partial areas are aligned in the Y direction. In the sixth embodiment, as shown in Fig. 23, the effective area AA is divided into ten rectangular partial areas that are long in the X direction, and the divided partial areas are aligned in the Y direction. A specific description will be given below.

[0108] As shown in FIG. 23 , the effective area AA according to the sixth embodiment is a combination of a first area A1, a second area A2, a third area A3, a fourth area A4, a fifth area A5, a sixth area A6, a seventh area A7, an eighth area A8, a ninth area A9, and a tenth area A10. The first area A1 to the tenth area A10 are arranged along the Y direction from the Y2 side to the Y1 side. When viewed from the Z direction, the first area A1 to the tenth area A10 are rectangular and extend in the X direction. The first area A1 to the tenth area A10 are each congruent in shape. In addition, drive electrodes extending in the X and Y directions are provided in each area.

[0109] As described above, in the panel unit 100E according to the sixth embodiment, the first to tenth regions A1 to A10, which are the multiple partial regions, are aligned along the Y direction. This allows for a simpler arrangement than an arrangement in which the multiple partial regions are aligned in both the X and Y directions, for example, and ultimately makes it possible to achieve dynamic light distribution control using fluctuations with a simpler configuration.

[0110] [First Modification] Next, a first modification will be described. Fig. 24 is a schematic diagram showing four liquid crystal panels stacked in the Z direction in the first modification.

[0111] In the panel unit 100A according to the second embodiment, as shown in Fig. 16, four liquid crystal panels 2 divided into five partial regions are stacked so that their outer edges are aligned. Specifically, as shown in Fig. 16, the panel unit 100A is formed by stacking a first liquid crystal panel 21A, a second liquid crystal panel 22A, a third liquid crystal panel 23A, and a fourth liquid crystal panel 24A in this order from the Z2 side to the Z1 side. Therefore, the first regions A1 of the first liquid crystal panel 21A, the second liquid crystal panel 22A, the third liquid crystal panel 23A, and the fourth liquid crystal panel 24A overlap when viewed from the Z direction, and the second regions A2 to the fifth regions A5 also overlap when viewed from the Z direction.

[0112] In contrast, in the panel unit 100F according to the first modification, the first liquid crystal panel 21A, the second liquid crystal panel 22A, the third liquid crystal panel 23A, and the fourth liquid crystal panel 24A are stacked in the Z direction while being sequentially shifted in the Y direction. Specifically, when the second liquid crystal panel 22A is stacked above (on the Z1 side of) the first liquid crystal panel 21A closest to the Z2 side, the second liquid crystal panel 22A is shifted in the Y1 direction relative to the first liquid crystal panel 21A by half the Y-direction length of the first region A1. Similarly, when the third liquid crystal panel 23A is stacked above the second liquid crystal panel 22A, the third liquid crystal panel 23A is shifted in the Y1 direction relative to the second liquid crystal panel 22A by half the Y-direction length of the first region A1. When the fourth liquid crystal panel 24A is placed above the third liquid crystal panel 23A, the fourth liquid crystal panel 24A is shifted toward the Y1 side by half the length of the first region A1 in the Y direction relative to the third liquid crystal panel 23A.

[0113] In this way, in the first modified example, the four liquid crystal panels 2 are stacked while being shifted toward the Y1 side by half the Y-direction length of the first region A1 as they move toward the Z1 side. In other words, among the first liquid crystal panel 21A to the fifth liquid crystal panel 25A, one liquid crystal panel 2 is positioned shifted in the Y direction relative to the other liquid crystal panels 2 adjacent to that one liquid crystal panel 2 in the Z direction.

[0114] As described above, in the lighting device according to the first modified example, among the multiple stacked liquid crystal panels, one liquid crystal panel (e.g., the first liquid crystal panel 21A) is positioned offset in the Y direction relative to the other liquid crystal panels (e.g., the second liquid crystal panel 22A).

[0115] According to this, for example, the Y2 side half of the first area A1 of the first liquid crystal panel 21A does not overlap with the first area A1 of the second liquid crystal panel 22A, and the Y1 side half of the first area A1 of the first liquid crystal panel 21A overlaps with the first area A1 of the second liquid crystal panel 22A.

[0116] Therefore, compared to a configuration in which one liquid crystal panel is not misaligned with respect to the other liquid crystal panels (for example, a configuration in which the entire outer edge of one liquid crystal panel overlaps with the entire outer edge of the other liquid crystal panel), the boundary between the transmitted light and the diffused light (see Figure 12) becomes less clear, and the fluctuation of the light passing through the panel unit 100F becomes greater.

[0117] [Second Modification] Next, a second modification will be described. Fig. 25 is a schematic diagram showing four liquid crystal panels stacked in the Z direction in the second modification.

[0118] In the panel unit 100G according to the second modified example, a first liquid crystal panel 21A, a second liquid crystal panel 22A, a third liquid crystal panel 23B, and a fourth liquid crystal panel 24B are stacked in this order from the Z2 side toward the Z1 side.

[0119] The first liquid crystal panel 21A and the second liquid crystal panel 22A have the same structure as the first liquid crystal panel 21A and the second liquid crystal panel 22A according to the second embodiment (see FIG. 16). The third liquid crystal panel 23B and the fourth liquid crystal panel 24B have the same structure as the liquid crystal panel 2B according to the third embodiment (see FIG. 18).

[0120] That is, in panel unit 100G, the two lower panels are the first liquid crystal panel 21A and the second liquid crystal panel 22A (rectangular partial area panels) of the same structure, and the two upper panels are the third liquid crystal panel 23B and the fourth liquid crystal panel 24B (right-angled triangular partial area panels) of the same structure.

[0121] Specifically, the rectangular partial area panels (first liquid crystal panel 21A and second liquid crystal panel 22A) have rectangular partial areas (first area A1 to fifth area A5) when viewed from the Z direction. In the first area A1 to fifth area A5, the direction in which the short sides A100 extend is along the Y direction.

[0122] The right-angled triangular partial area panels (third liquid crystal panel 23B and fourth liquid crystal panel 24B) have right-angled triangular partial areas (sixth area A11 and seventh area A12) when viewed from the Z direction. In the sixth area A11 and the seventh area A12, the short side A200 of the two orthogonal sides of the right triangle overlaps with the short side A100.

[0123] As described above, the illumination device according to the second modification includes rectangular partial-area panels (first liquid crystal panel 21A and second liquid crystal panel 22A) and right-angled triangular partial-area panels (third liquid crystal panel 23B and fourth liquid crystal panel 24B). In the first to fifth areas A1 to A5, the direction in which the short sides A100 extend is along the Y direction. In the sixth and seventh areas A11 and A12, the short sides A200 overlap with the short sides A100.

[0124] According to this, for example, the Y2 side portion of the first region A1 of the second liquid crystal panel 22A overlaps with the sixth region A11 of the third liquid crystal panel 23B, and the Y1 side portion of the first region A1 of the second liquid crystal panel 22A overlaps with the seventh region A12 of the third liquid crystal panel 23B.

[0125] Therefore, the variety of ways in which voltage can be supplied increases, such as a way in which voltage is supplied to the first area A1 of the second liquid crystal panel 22A and the sixth area A11 of the third liquid crystal panel 23B, a way in which voltage is supplied to the first area A1 of the second liquid crystal panel 22A and the seventh area A12 of the third liquid crystal panel 23B, and a way in which voltage is supplied to the first area A1 of the second liquid crystal panel 22A and the sixth area A11 and seventh area A12 of the third liquid crystal panel 23B.

[0126] 1 lighting device 2, 2A, 2B, 2C, 2D liquid crystal panel 21, 21A first liquid crystal panel 22, 22A second liquid crystal panel 23, 23A, 23B third liquid crystal panel 24, 24A, 24B fourth liquid crystal panel 32 liquid crystal layer 33 light source 35 liquid crystal molecules 10, 10a, 10b, 10c, 10d, 10e, 10f drive electrode 13, 13a, 13b, 13c, 13d, 13e, 13f drive electrode 100, 100A, 100C, 100D, 100E, 100F, 100G panel unit 113 memory circuit 1131 setting circuit (DIP switch) AA effective area A1 first area (partial area) A2 second area (partial area) A3 third area (partial area) A4 4th area (partial area) A5 5th area (partial area) A11 6th area (partial area) A12 7th area (partial area)

Claims

1. An illumination device comprising: a light source; and a panel unit arranged on the optical axis of the light source, wherein the panel unit has a plurality of liquid crystal panels stacked in a first direction along the optical axis, wherein the effective area of ​​at least one of the plurality of liquid crystal panels includes a plurality of partial areas, and each of the plurality of partial areas is switchable between transmitting light and diffusing light.

2. The lighting device according to claim 1, wherein each of the plurality of partial regions has a drive electrode to which a voltage supplied can be individually controlled, and the light transmission and light diffusion in each of the plurality of partial regions are switched depending on the voltage of the drive electrode.

3. The lighting device according to claim 2, wherein the plurality of partial regions are aligned in a second direction that intersects with the first direction.

4. The lighting device according to claim 3, wherein one of the plurality of liquid crystal panels is positioned offset in the second direction relative to another liquid crystal panel adjacent to the one liquid crystal panel in the first direction.

5. The lighting device described in claim 3, wherein the plurality of liquid crystal panels include a rectangular partial area panel and a right-angled triangular partial area panel stacked on the rectangular partial area panel, wherein the rectangular partial area panel has a rectangular partial area whose short side extends along the second direction when viewed from the first direction, and wherein the right-angled triangular partial area panel has a partial area that is a right triangle when viewed from the first direction, and the short side of the two orthogonal sides of the right triangle overlaps with the short side of the partial area of ​​the rectangular partial area panel.

6. The lighting device according to claim 2, further comprising a setting circuit for setting which of the plurality of partial regions is to be made light-transmitting and which is to be made to diffuse light.

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