Illumination device

Abstract

This illumination device comprises: a light source for illuminating a target space; and a light-shielding element disposed on the optical path of light emitted from the light source. The light-shielding element includes: a first liquid crystal panel including a first substrate, a second substrate opposite to the first substrate, and a first liquid crystal layer between the first substrate and the second substrate; and a first polarizing plate and a second polarizing plate arranged in crossed Nicols or parallel Nicols, with the first liquid crystal panel interposed therebetween. The first liquid crystal panel has a first common electrode and a plurality of first driving electrodes. The light-shielding element is controlled between a light-shielding mode in which the plurality of first drive electrodes individually block light from the light source, and a transmission mode in which the plurality of first drive electrodes individually transmit light from the light source.

Description

lighting equipment

[0001] An embodiment of the present invention relates to a lighting device that can control the range of light irradiation by utilizing the electro-optical effect of liquid crystal.

[0002] As an illumination device utilizing the electro-optical effect of liquid crystals, a lighting device capable of adjusting the amount of emitted light for each direction of light irradiation using a liquid crystal cell arranged to cover the light source has been disclosed (see Patent Document 1). Also, a lighting device has been disclosed in which light emitted from a light source passes through a liquid crystal cell to form a periodic pattern of multiple non-overlapping spot lights on a projection surface (see Patent Document 2).

[0003] JP 2018-073661 A JP 2013-505472 A

[0004] Lighting fixtures that emit spotlights installed in rooms can adjust the brightness using a dimming function, but the position of the light source is fixed, so the position of the light cannot be freely changed.In addition, in trains and airplanes, there are examples where reading lights attached to flexible tubes are installed in each passenger seat, but in order to change the position of the light, the user must directly bend the flexible tube.

[0005] An object of one embodiment of the present invention is to provide a device that is capable of changing the illumination position and illumination range of a spotlight even when the position of the light source remains fixed.

[0006] An illumination device according to one embodiment of the present invention includes a light source for illuminating a target space and a light-blocking element arranged on an optical path of light emitted from the light source. The light-blocking element includes a first liquid crystal panel including a first substrate, a second substrate facing the first substrate, and a first liquid crystal layer between the first and second substrates, and first and second polarizing plates arranged in a crossed Nicol or parallel Nicol configuration across the first liquid crystal panel. The first liquid crystal panel includes a first common electrode and a plurality of first drive electrodes. The light-blocking element is configured such that each of the plurality of first drive electrodes is individually controlled to a light-blocking mode in which it blocks light from the light source and a transmission mode in which it transmits light from the light source.

[0007] 1 is a diagram showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 3 is a diagram showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 4 is a diagram showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 5 is a developed view showing the configuration of a light-blocking element used in an illumination device according to an embodiment of the present invention. FIG. 6 is a developed view showing the configuration of a light-blocking element used in an illumination device according to an embodiment of the present invention. FIG. 7 is a developed view showing the configuration of a light-blocking element used in an illumination device according to an embodiment of the present invention. FIG. 8 is a cross-sectional view showing the configuration of a light-blocking element used in an illumination device according to an embodiment of the present invention. FIG. 9 is a diagram showing an irradiation pattern of irradiation light irradiated by an illumination device according to an embodiment of the present invention. FIG. 10 is a perspective view showing the configuration of a liquid crystal light control element used in an illumination device according to an embodiment of the present invention. FIG. 11 is a cross-sectional view showing the operation of a liquid crystal light control element used in an illumination device according to an embodiment of the present invention. FIG. 12 is a cross-sectional view showing the operation of a liquid crystal light control element used in an illumination device according to an embodiment of the present invention. FIG. 13 is a developed view showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 14 is a developed view showing the configuration of an illumination device according to an embodiment of the present invention. FIG. 1 is a development view showing the configuration of a lighting device according to one embodiment of the present invention. FIG. 2 is a plan view showing the configuration of a drive electrode of a light-shielding element used in a lighting device according to one embodiment of the present invention. FIG. 3 is a cross-sectional view showing the configuration of a light-shielding element used in a lighting device according to one embodiment of the present invention. FIG. 4 is a view showing the waveform of a drive signal for driving a light-shielding element used in a lighting device according to one embodiment of the present invention. FIG. 5 is a cross-sectional view showing the configuration of a light-shielding element used in a lighting device according to one embodiment of the present invention. FIG. 6 is a plan view showing the configuration of a drive electrode of a light-shielding element used in a lighting device according to one embodiment of the present invention.FIG. 1 is a plan view showing the configuration of a drive electrode of a light-blocking element used in a lighting device according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of a drive electrode of a light-blocking element used in a lighting device according to an embodiment of the present invention. FIG. 3 is a diagram showing the configuration of a light-blocking element used in a lighting device according to an embodiment of the present invention. FIG. 4 is a plan view showing the arrangement of drive electrodes of a light-blocking element used in a lighting device according to an embodiment of the present invention. FIG. 5 is a plan view showing the arrangement of drive electrodes of a light-blocking element used in a lighting device according to an embodiment of the present invention. FIG. 6 is a plan view showing the arrangement of drive electrodes of a light-blocking element used in a lighting device according to an embodiment of the present invention.

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention can be implemented in many different forms, and should not be construed as being limited to the description of the embodiments exemplified below. For clarity of explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual form, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals (or reference numerals with A, B, etc. suffixed thereto), and detailed descriptions may be omitted as appropriate. Furthermore, the letters "first" and "second" attached to each element are convenient labels used to distinguish each element and have no further meaning unless otherwise specified.

[0009] In this specification, when a component or region is referred to as being "on (or under)" another component or region, unless otherwise specified, this includes not only the case where it is directly above (or directly under) the other component or region, but also the case where it is above (or under) the other component or region, i.e., the case where another component is included between the component or region and above (or under) the other component or region.

[0010] In this specification, "light distribution" refers to the degree of spread of light emitted from a light source, i.e., the distribution of luminous intensity (light intensity) in each direction, in the usual sense, and controlling the light distribution means intentionally controlling the degree of spread of light emitted from a light source.

[0011] In this specification, "optical rotation" refers to the phenomenon in which the polarization axis of a linearly polarized component is rotated when passing through a liquid crystal layer.

[0012] In this specification, the "alignment direction" of an alignment film refers to the direction in which liquid crystal molecules are aligned when the alignment film is subjected to a treatment (e.g., a rubbing treatment) that imparts an alignment restraining force to the alignment film and aligns the liquid crystal molecules on the alignment film. When the treatment performed on the alignment film is a rubbing treatment, the alignment direction of the alignment film is usually the rubbing direction.

[0013] In this specification, the "extension direction" of a strip electrode refers to the direction in which the long side of a pattern having a short side (width) and a long side (length) extends when the strip electrode is viewed in a plan view.

[0014] First Embodiment An illumination device according to one embodiment of the present invention has a function of irradiating a specific area with light emitted from a light source as a spotlight, and also has a function of moving the irradiation position of the spotlight.

[0015] 1A shows the configuration of a lighting device 100 according to one embodiment of the present invention. The lighting device 100 according to this embodiment includes a light source 102 that illuminates a target space and a shading element 104 that can partially block light emitted from the light source 102. The target space is a space to which illumination is provided, and includes various spaces such as spaces related to human life and production activities, such as homes, offices, and factories, spaces inside passenger compartments of automobiles, trains, ships, and aircraft, and spaces for growing plants in plant factories.

[0016] In this embodiment, the light source 102 is preferably a point light source that emits light radially, or a light source that can be substantially regarded as a point light source. The light source 102 is, for example, an LED light source. Alternatively, a halogen lamp, a xenon lamp, or the like may be used as the light source 102.

[0017] The light-blocking element 104 is an element that utilizes the electro-optical effect of liquid crystal. The light-blocking element 104 has a function of electrically controlling a light-transmitting state and a light-blocking state. As shown in FIG. 1A , the light-blocking element 104 is disposed between the light source 102 and the irradiation surface 200 onto which the light emitted from the light source 102 is irradiated. In other words, the light-blocking element 104 is disposed in the optical path of the emitted light so as to block the light emitted from the light source 102.

[0018] The light-blocking element 104 includes a liquid crystal panel 1044. The liquid crystal panel 1044 includes a first substrate S01, a second substrate S02 facing the first substrate S01, and a liquid crystal layer LC01 between the first substrate S01 and the second substrate S02. The liquid crystal panel 1044 is divided into a plurality of regions SG, and the light-blocking state and the light-transmitting state can be controlled for each of the regions SG. In other words, the light-blocking element 104 has a plurality of regions SG, and each of the plurality of regions SG can be switched between a light-blocking mode in which light is blocked and a light-transmitting mode in which light is transmitted.

[0019] The transmission mode is a state in which light emitted from the light source 102 is transmitted, and the light blocking mode is a state in which light emitted from the light source 102 is blocked. Although not shown in detail in FIG. 1A , the liquid crystal panel 1044 is provided with a common electrode and a plurality of drive electrodes, and the drive electrodes enable control of the light blocking mode and the transmission mode for each region SG. Also, although not shown in FIG. 1A , the light blocking element 104 can be switched between the transmission mode and the light blocking mode by combining the liquid crystal panel 1044 with optical components (such as a polarizing plate) not shown.

[0020] 1A schematically shows a state in which all regions SG of the light-blocking element 104 are controlled to the transmission mode. Meanwhile, FIG. 1B shows a state in which a specific region SG_1 is set to the transmission mode, and the other regions SG are set to the light-blocking mode. In this state, light that has passed through the region SG_1 controlled to the transmission mode is irradiated onto the irradiation surface 200, while light is not transmitted through the region SG controlled to the light-blocking mode. As is clear from comparison with FIG. 1A, in the state shown in FIG. 1B, the light emitted from the light source 102 is irradiated onto the irradiation surface 200 as a spotlight.

[0021] The light-blocking element 104 has multiple regions SG, each of which can be set to either the transmission mode or the light-blocking mode. Therefore, by changing the position of the region SG_1 set to the transmission mode, the spotlight irradiation position can be changed. While FIG. 1B shows an example in which one region SG_1 among the multiple regions SG is controlled to the transmission mode, the present invention is not limited to this example, and several regions among the multiple regions SG may be collectively controlled to the transmission mode.

[0022] As will be described later, the region SG may be a region defined by a common electrode provided on the liquid crystal panel and one drive electrode opposite the common electrode, or may be a region defined by a set of multiple drive electrodes adjacent to each other.

[0023] 1A , when an LED light source is used as the light source 102, for example, the light distribution angle θ of the emitted light is approximately ±60 degrees. As shown in FIG. 1A , the lighting device 100 may be provided with a light blocking plate 106 to prevent the light emitted from the light source 102 from leaking out without being blocked by the light blocking element 104. There are no limitations on the shape of the light blocking plate 106, but it is preferable that the light blocking plate 106 have a shape that surrounds the space between the light source 102 and the light blocking element 104.

[0024] As shown in FIG. 1C , the lighting device 100 may be provided with an optical system 107 between the light source 102 and the light-blocking element 104 to impart directionality to the light emitted from the light source 102. The optical system 107 may be composed of at least one lens. By using the optical system 107, it is possible to adjust the light distribution angle of the light emitted from the light source 102 and prevent the emitted light from diffusing outside the light-blocking element 104. Furthermore, as shown in FIG. 1D , a reflector 108 may be disposed around the light source 102. By disposing the reflector 108, it is possible to control the light distribution of the light emitted from the light source 102. The configuration of the optical system 107 shown in FIG. 1C and the configuration of the reflector 108 shown in FIG. 1D may be combined with the light-blocking plate 106 shown in FIG. 1A .

[0025] The lighting device 100 according to this embodiment has a configuration in which a light source 102 and a light-blocking element 104 are combined. The light-blocking element 104 limits the illumination area of ​​light emitted from the light source 102 to a specific area, thereby enabling spotlight illumination. The light-blocking element 104 can arbitrarily control the area to be set in the light-blocking mode and the area to be set in the transmission mode, and this control can be performed dynamically, allowing the illumination position of the spotlight to be freely moved.

[0026] The size (area in a plan view) of the light-blocking element 104 can be provided in a range from small to large, similar to the size of a liquid crystal display. Therefore, it is possible to provide lighting devices 100 of various sizes, from narrow to wide, in which the range over which the spotlight can be moved.

[0027] 2A and 2B, the operation of the light blocking element 104 will be described. Figures 2A and 2B are development views of the light blocking element 104, showing the configuration of one region that can be controlled to a light blocking mode and a light transmitting mode.

[0028] 2A and 2B, the X, Y, and Z axis directions are shown for the sake of explanation. The X and Y axis directions are orthogonal in a plan view, and the Z axis direction extends in a normal direction to the X-Y plane. In the following description, expressions such as the X axis direction, the Y axis direction, and the Z axis direction are used to specify directions, but these expressions can also be replaced with expressions such as the X axis direction being the first direction, the Y axis direction being the second direction, and the Z axis direction being the third direction or the up-down direction. Unless otherwise specified, these X, Y, and Z axis directions are the same when referring to other drawings.

[0029] The light-blocking element 104 includes a liquid crystal panel 1044, a first polarizer 1042, and a second polarizer 1046. The liquid crystal panel 1044 includes a common electrode COM, a first substrate S01 provided with a first alignment film AF01, a second substrate S02 provided with a drive electrode SE and a second alignment film AF02, and a liquid crystal layer LC01 between the first substrate S01 and the second substrate S02. The first alignment film AF01 is provided to cover the common electrode COM, and the second alignment film AF02 is provided to cover the drive electrode SE. The alignment directions of the first alignment film AF01 and the second alignment film AF02 are determined by an alignment treatment such as rubbing. In the example shown in FIGS. 2A and 2B , the alignment direction AD1 of the first alignment film AF01 is oriented in the Y-axis direction, and the alignment direction AD2 of the second alignment film AF02 is oriented in the X-axis direction. That is, the alignment direction AD1 of the first alignment film AF01 and the alignment direction AD2 of the second alignment film AF02 are in a cross (orthogonal) relationship.

[0030] The liquid crystal panel 1044 is a transmissive panel. The common electrode COM and the drive electrodes SE are formed of a transparent conductive film. Metal auxiliary wiring may be added to the transparent conductive film to reduce sheet resistance. The common electrode COM and the drive electrodes SE may also be formed of a mesh-like metal film having light-transmitting properties.

[0031] The liquid crystal layer LC01 is formed of, for example, twisted nematic liquid crystal (TN (Twisted Nematic) liquid crystal). FIGS. 2A and 2B schematically show liquid crystal molecules LCM of the liquid crystal layer LC01. The liquid crystal molecules LCM have a long, thin, rod-like molecular structure. The initial alignment state of the liquid crystal molecules LCM on the first substrate S01 side is regulated by the alignment direction AD1 of the first alignment film AF01, and on the second substrate S02 side is regulated by the alignment direction AD2 of the second alignment film AF02. That is, the liquid crystal molecules LCM on the first substrate S01 side have their major axes aligned in the same direction as the alignment direction AD1 of the first alignment film AF01, and the liquid crystal molecules LCM on the second substrate side have their major axes aligned in the same direction as the alignment direction AD2 of the second alignment film AF02. Due to this alignment regulation force, the liquid crystal molecules LCM in the liquid crystal layer LC01 are aligned in a state twisted by 90 degrees from the first substrate S01 to the second substrate S02.

[0032] The first polarizer 1042 is disposed on the first substrate S01 side, and the second polarizer 1046 is disposed on the second substrate S02 side. The first polarizer 1042 and the second polarizer 1046 are absorptive linear polarizers. A linear polarizer has the property of transmitting polarized light components parallel to its transmission polarization axis and absorbing (not transmitting) other polarized light components. The transmission polarization axis TA1 of the first polarizer 1042 is disposed parallel to the alignment direction AD1 of the first alignment film AF01, and the transmission polarization axis TA2 of the second polarizer 1046 is disposed so as to intersect (orthogonal to) the alignment direction AD2 of the second alignment film AF02. In other words, the transmission polarization axis TA1 of the first polarizer 1042 and the transmission polarization axis TA2 of the second polarizer 1046 are disposed parallel (parallel Nicols).

[0033] 2A illustrates a case in which light having a first polarization component PL1 and a second polarization component PL2 emitted from a light source 102 (not shown) is incident on the first polarizer 1042. Here, the polarization direction of the first polarization component PL1 is parallel to the Y-axis direction, and the polarization direction of the second polarization component PL2 is parallel to the X-axis direction. When light having such polarization components is incident on the first polarizer 1042, the first polarization component PL1, which is parallel to the transmission polarization axis TA1, is transmitted, and the second polarization component PL2 is absorbed. Therefore, of the light emitted from the light source 102 (not shown), only the first polarization component PL1 is selectively transmitted through the first polarizer 1042 and incident on the liquid crystal panel 1044.

[0034] 2A shows the off state in which no voltage is applied between the common electrode COM and the drive electrode SE. As the first polarized component PL1 passes through the liquid crystal layer LC01 from the first substrate S01 side to the second substrate S02 side, the polarization axis of the first polarized component PL1 is rotated by 90 degrees and transitions to the second polarized component PL2 due to the 90-degree twisted orientation of the liquid crystal molecules LCM. The transmission polarization axis TA2 of the second polarizer 1046 intersects with the polarization axis of the second polarized component PL2. Therefore, the second polarized component PL2 emitted from the liquid crystal panel 1044 is absorbed by the second polarizer 1046. In other words, in the off state in which no voltage is applied between the common electrode COM and the drive electrode SE of the liquid crystal panel 1044, light emitted from the light source 102 (not shown) is blocked by the light-blocking element 104 and does not exit to the outside.

[0035] 2B shows the ON state in which a voltage is applied between the common electrode COM and the drive electrode SE. In the ON state, the long axis direction of the liquid crystal molecules LCM is oriented parallel to the electric field generated between the common electrode COM and the drive electrode SE. That is, in the ON state, the long axis direction of the liquid crystal molecules LCM is oriented vertically between the first substrate S01 and the second substrate S02. Therefore, the 90-degree twisted state of the liquid crystal molecules LCM is eliminated, and the first polarized component PL1 incident on the liquid crystal panel 1044 from the first polarizer 1042 is not rotated by the liquid crystal layer LC01 and passes through as the first polarized component PL1.

[0036] The polarization axis of the first polarized component PL1 that has passed through the liquid crystal panel 1044 is parallel to the transmission polarization axis TA2 of the second polarizer 1046. Therefore, in the on state where a voltage is applied to the common electrode COM and the drive electrode SE of the liquid crystal panel 1044, light emitted from the light source 102 (not shown) passes through the light-blocking element 104 and is emitted to the outside.

[0037] 2A and 2B, the liquid crystal panel 1044 can be controlled to switch between a light-blocking mode in which incident light is blocked and a light-transmitting mode in which incident light is transmitted, depending on the state of voltage applied to the liquid crystal panel 1044. That is, the light-blocking element 104 can switch between the light-blocking mode and the light-transmitting mode as appropriate depending on the presence or absence of a drive voltage. Note that while FIGS. 2A and 2B show the relationship between the common electrode COM and one drive electrode SE, by arranging a plurality of drive electrodes SE relative to the common electrode COM, it is possible to freely change the region and range through which light emitted from the light source 102 transmits.

[0038] 2C and 2D show an example of a light-blocking element in which the transmission polarization axis TA2 of the second polarizer 1046 is arranged parallel to the X-axis direction, as compared with the light-blocking element 104 shown in Figures 2A and 2B. That is, the light-blocking element 104 is shown in which the transmission polarization axis TA1 of the first polarizer 1042 and the transmission polarization axis TA2 of the second polarizer 1046 are arranged orthogonal to each other (crossed Nicols).

[0039] 2C shows an OFF state in which no voltage is applied between the common electrode COM and the drive electrode SE. In this state, the polarization direction of the second polarized component PL2 emitted from the liquid crystal panel 1044 is parallel to the transmission polarization axis TA2 of the second polarizer 1046, so that light emitted from the light source 102 (not shown) passes through the second polarizer 1046 and is emitted to the outside. On the other hand, FIG. 2D shows an ON state in which a voltage is applied between the common electrode COM and the segment drive electrode SE. In this state, the polarization direction of the first polarized component PL2 emitted from the liquid crystal panel 1044 is parallel to the transmission polarization axis TA2 of the second polarizer 1046, so that light emitted from the light source 102 (not shown) does not pass through the second polarizer 1046 and is not emitted to the outside.

[0040] In this way, the light-shielding element 104 according to this embodiment can control the light-shielding mode and the transmission mode whether the pair of polarizing plates (first polarizing plate 1042, second polarizing plate 1046) is arranged in a parallel Nicol or a crossed Nicol configuration.

[0041] 2A to 2D show two states of the liquid crystal panel 1044, a light blocking mode and a transmissive mode, but it can also be controlled to a semi-transmissive mode in which the orientation of the liquid crystal molecules is in an intermediate state.

[0042] 2A to 2D show a configuration in which one drive electrode SE is arranged relative to the common electrode COM, but the light-blocking element 104 can arrange multiple drive electrodes SE relative to the common electrode COM and individually control the voltage application state. This configuration makes it possible to change the irradiation position of the spotlight. Furthermore, by successively switching the drive electrodes SE to the transmissive mode, it is possible to create the appearance of the spotlight moving continuously.

[0043] 3 shows a cross-sectional view of the light-shielding element 104. The light-shielding element 104 has a structure in which a first drive electrode SE_01, a second drive electrode SE_02, and a third drive electrode SE_03 are arranged to face a common electrode COM.

[0044] The first drive electrode SE_01, the second drive electrode SE_02, and the third drive electrode SE_03 are individually controlled to be on (a state in which a voltage is applied) and off (a state in which no voltage is applied). Fig. 3 shows a case in which the first drive electrode SE_01 and the third drive electrode SE_03 are in the off state and the second drive electrode SE_02 is in the on state. The regions corresponding to the first drive electrode SE_01 and the third drive electrode SE_03 form light-blocking mode regions that do not transmit light emitted from the light source 102 (not shown). The region corresponding to the second drive electrode SE_02 forms a transmissive mode region that transmits light emitted from the light source 102 (not shown).

[0045] As shown in FIG. 3 , the first drive electrode SE_01, the second drive electrode SE_02, and the third drive electrode SE_03 are spaced apart. Liquid crystal is also present in the region between the first drive electrode SE_01 and the second drive electrode SE_02, and in the region between the second drive electrode SE_02 and the third drive electrode SE_03. The liquid crystal in the region between these electrodes is in an initial alignment state due to the alignment restriction force of the first alignment film AF01 and the second alignment film AF02. Because the electric field generated by the drive electrodes SE (SE_01 to SE_03) barely acts on this region between the electrodes, the alignment state of the liquid crystal molecules LCM is maintained in the initial alignment state. Therefore, the region between the drive electrodes SE (SE_01 to SE_03) is in a light-blocking mode, and a state in which light does not pass through is maintained.

[0046] In the first polarizing plate 1042, the polarization component (second polarization component PL2) that is not parallel to the transmission polarization axis is absorbed by the first polarizing plate 1042. Since the lighting device 100 is irradiated with strong light from the light source 102, there is a concern that if the first polarizing plate 1042 absorbs the light emitted from the light source 102, the polarization component may be deteriorated due to heat generation. To address this issue, the light-blocking element 104 shown in FIG. 3 has a structure in which a first brightness enhancement film 1048A is provided on the surface of the first polarizing plate 1042 opposite the first substrate S01 side (i.e., the surface on the light incident side). The first brightness enhancement film 1048A has the property of transmitting a specific polarization component and reflecting other polarization components. That is, the first brightness enhancement film 1048A has the property of transmitting the first polarization component PL1 and reflecting the second polarization component PL2. By aligning the transmission axis of the first brightness enhancement film 1048A with the transmission polarization axis of the first polarizer 1042, light absorption in the first polarizer 1042 can be suppressed.

[0047] Similarly, a second brightness enhancement film 1048B may be provided between the second substrate S02 and the second polarizing plate 1046. The polarized light component that passes through the first polarizing plate 1042, is rotated by 90 degrees in the liquid crystal layer LC01, and transitions to the second polarized light component PL2 intersects with the transmission polarization axis of the second polarizing plate 1046 and is absorbed by the second polarizing plate 1046, causing heat generation. Therefore, by providing the second brightness enhancement film 1048B and arranging it so that its transmission axis coincides with the transmission polarization axis of the second polarizing plate 1046, the second polarized light component PL2 can be reflected and light absorption by the second polarizing plate 1046 can be suppressed.

[0048] 1B , under the condition that the light emitted from the light source 102 is blocked by the light blocking element 104 and a spotlight is irradiated onto a specific area, most of the area becomes a light-blocking area. Under such a condition, heat generation from the first polarizing plate 1042 and the second polarizing plate 1046 becomes a problem. However, by providing the first brightness enhancing film 1048A and the second brightness enhancing film 1048B as shown in FIG. 3 , the polarized light component that would normally be absorbed by the polarizing plate can be reflected, thereby suppressing heat generation.

[0049] The lighting device 100 according to this embodiment is configured such that a light-blocking element 104 using liquid crystal is disposed so as to block light emitted from the light source 102, and the light-blocking element 104 is provided with a plurality of regions that can be controlled to a light-blocking mode or a transmission mode, thereby enabling the light emitted from the light source 102 to be partially irradiated like a spotlight. The position and range of the transmission region (transmission mode region) of the illumination light controlled by the light-blocking element 104 can be freely adjusted, so that the position of the spotlight can be changed and illumination can be provided as if the spotlight were moving continuously.

[0050] Although this embodiment shows an example in which the common electrode COM is provided on the first substrate S01 of the liquid crystal panel 1044 and the drive electrode SE is provided on the second substrate S02, the configuration of the liquid crystal panel 1044 is not limited to this example, and the common electrode COM may be provided on the second substrate S02 and the drive electrode SE may be provided on the first substrate. Furthermore, this embodiment shows a case in which the liquid crystal panel 1044 is of a TN type using twisted nematic liquid crystal, but the liquid crystal panel 1044 can be of various types such as a VA (Vertical Alignment) type, an MVA (Multi-domain Vertical Alignment) type, an IPS (In Plane Switching) type, an FFS (Fringe Field Switching) type, or a liquid crystal panel using a polymer dispersed liquid crystal.

[0051] Second Embodiment This embodiment shows a configuration in which a liquid crystal light control element 120 is added to the configuration of the lighting device shown in the first embodiment.

[0052] 4A shows the configuration of an illumination device 100 according to this embodiment. The illumination device 100 according to this embodiment includes a light source 102, a light-blocking element 104, and a liquid crystal light control element 120. The liquid crystal light control element 120 is disposed on the light-emitting side of the light-blocking element 104. The liquid crystal light control element 120 has a function of controlling the light distribution state (spread of light). Specifically, the liquid crystal light control element 120 can diffuse light in a specific direction to form a line-shaped light distribution pattern (line light distribution), a cross-shaped light distribution pattern (cross light distribution), a rectangular light distribution pattern, or the like.

[0053] For example, Fig. 4B shows an irradiation pattern when a line light distribution is formed by the liquid crystal light control element 120. As shown in Fig. 4B, by passing the spotlight irradiation pattern A formed by the light-blocking element 104 through the liquid crystal light control element 120, a line-shaped irradiation pattern B that is wider than the irradiation pattern A can be formed. In this way, by passing the light through the liquid crystal light control element 120 in addition to the light-blocking element 104, it is possible to emit a spotlight with a controlled light distribution state.

[0054] FIG. 5 shows a perspective view of the first liquid crystal cell 1221 constituting the liquid crystal light control element 120. The first liquid crystal cell 1221 includes a first substrate S11, a second substrate S12, a first electrode E11, a second electrode E12, a first alignment film AL11, a second alignment film AL12, and a first liquid crystal layer LC1. The first substrate S11 is provided with the first electrode E11 and the first alignment film AL11, and the second substrate S12 is provided with the second electrode E12 and the second alignment film AL12. The first alignment film AL11 is provided to cover the first electrode E11, and the second alignment film AL12 is provided to cover the second electrode E12. The first substrate S11 and the second substrate S12 are disposed opposite each other and spaced apart from each other. A first liquid crystal layer LC1 is disposed between the first substrate S11 and the second substrate S12.

[0055] The first electrode E11 includes a first strip electrode E11A and a second strip electrode E11B each having a plurality of strip-shaped patterns. The second electrode E12 includes a third strip electrode E12A and a fourth strip electrode E12B each having a plurality of strip-shaped patterns. The first strip electrodes E11A and the second strip electrodes E11B are alternately arranged on the insulating surface of the first substrate S11, and the third strip electrodes E12A and the fourth strip electrodes E12B are alternately arranged on the insulating surface of the second substrate S12. The longitudinal direction of the plurality of strip-shaped patterns of the first strip electrode E11A and the second strip electrode E11B extends in the Y-axis direction. The longitudinal direction of the plurality of strip-shaped patterns of the third strip electrode E12A and the fourth strip electrode E12B extends in the X-axis direction. Therefore, the direction in which the multiple strip patterns of the third strip electrodes E12A and the fourth strip electrodes E12B extend is orthogonal (intersecting at 90 degrees) to the direction in which the multiple strip patterns of the first strip electrodes E11A and the second strip electrodes E11B extend. The relative arrangement of the first strip electrodes E11A and the second strip electrodes E11B and the third strip electrodes E12A and the fourth strip electrodes E12B is not limited to being orthogonal, and may be changed within a range of ±10 degrees from 90 degrees.

[0056] The alignment direction ALD1 of the first alignment film AL11 is oriented in a direction (Y-axis direction) intersecting the extension direction of the first strip electrodes E11A and the second strip electrodes E11B. The alignment direction ALD2 of the second alignment film AL12 is oriented in a direction (X-axis direction) intersecting the extension direction of the third strip electrodes E12A and the fourth strip electrodes E12B. The angle at which the extension direction of the first strip electrodes E11A and the second strip electrodes E11B intersects with the alignment direction ALD1, and the angle at which the extension direction of the third strip electrodes E12A and the fourth strip electrodes E12B intersects with the alignment direction ALD2 can be set within a range of 90±10 degrees.

[0057] The first substrate S11 and the second substrate S12 are disposed opposite each other with a gap of 10 μm or more. For example, the first substrate S11 and the second substrate S12 are disposed with a gap of 10 μm or more and 1000 μm or less, preferably 20 μm or more and 500 μm or less. A first liquid crystal layer LC1 provided between the first substrate S11 and the second substrate S12 has a thickness D. A first electrode E11, a second electrode E12, a first alignment film AL11, and a second alignment film AL12 are provided between the first substrate S11 and the second substrate S12, but the film thicknesses of these components are negligibly small compared to the gap between the first substrate S11 and the second substrate S12. Therefore, the gap between the first substrate S11 and the second substrate S12 can be considered the thickness D of the first liquid crystal layer LC1. That is, the thickness D of the first liquid crystal layer LC1 can be regarded as being 10 μm or more and 1000 μm or less, preferably 20 μm or more and 500 μm or less. Although not shown in FIG. 5, a spacer may be provided between the first substrate S11 and the second substrate S12.

[0058] The liquid crystal material forming the first liquid crystal layer LC1 can be twisted nematic liquid crystal, similar to that of the light-blocking element 104. As shown schematically in FIG. 5 , the liquid crystal molecules have elongated rod-like structures due to their molecular structure. The rod-like liquid crystal molecules have dielectric anisotropy and refractive index anisotropy in the long axis direction (parallel to the molecular long axis) and the short axis direction (perpendicular to the molecular long axis). The first liquid crystal cell 1221 is provided with a first alignment film AL11 and a second alignment film AL12 to control the alignment direction of the liquid crystal molecules. FIG. 5 shows that the alignment direction ALD1 of the first alignment film AL11 is parallel to the Y axis, and the alignment direction ALD2 of the second alignment film AL12 is parallel to the X axis.

[0059] When no control signal is applied to the first electrode E11 and the second electrode E12, the liquid crystal molecules LCM of the first liquid crystal layer LC1 have their major axes aligned in the alignment directions ALD1 and ALD2 of the alignment films due to the alignment restricting forces of the first alignment film AL11 and the second alignment film AL12. The alignment direction ALD1 of the first alignment film AL11 and the alignment direction ALD2 of the second alignment film AL12 intersect (are perpendicular to each other), so the alignment direction of the major axes of the liquid crystal molecules LCM gradually changes so as to be twisted by 90 degrees from the first substrate S11 to the second substrate S12.

[0060] 6A and 6B are diagrams illustrating the operation of the first liquid crystal cell 1221. Fig. 6A shows a state in which no control signal is applied to the first electrode E11 (first strip electrode E11A and second strip electrode E11B), while Fig. 6B shows a state in which a control signal is applied to the first electrode E11 and a transverse electric field is generated between the first strip electrode E11A and the second strip electrode E11B. The control signal is a voltage signal that generates a transverse electric field between the first strip electrode E11A and the second strip electrode E11B such that the alignment state of the liquid crystal molecules LCM is oriented in a direction parallel to the electric field. The same applies to the control signal for the third strip electrode E12A and the fourth strip electrode E12B.

[0061] The first strip-shaped electrodes E11A and the second strip-shaped electrodes E11B are arranged with a distance WD between them, with the longitudinal direction of the strip-shaped pattern extending in the X-axis direction. Comparing the thickness D of the first liquid crystal layer LC1 with the electrode distance WD between the first electrodes E11, the thickness D of the first liquid crystal layer LC1 is equal to or greater than the electrode distance WD (D≧WD). For example, the thickness D of the first liquid crystal layer LC1 is at least twice the electrode distance WD between the first electrodes E11. When the thickness D of the first liquid crystal layer LC1 is 10 μm, the electrode distance WD can be 5 μm, and when the thickness D of the first liquid crystal layer LC1 is 50 μm, the electrode distance WD can be 10 μm.

[0062] The alignment direction ALD1 of the first alignment film AL11 extends in the X-axis direction, and the alignment direction ALD2 of the second alignment film AL12 extends in the Y-axis direction. When no electric field is applied to the first liquid crystal layer LC1 ( FIG. 6A ), the first liquid crystal layer LC1 is aligned in a state twisted 90 degrees from the first substrate S11 side to the second substrate S12 side. In this state, the first liquid crystal layer LC1 has a uniform refractive index distribution. When light enters the first liquid crystal cell 1221, the polarized components of the incident light are rotated by the twist of the liquid crystal molecules LCM. The incident light passes through the first liquid crystal layer LC1 while being rotated without being refracted (or scattered).

[0063] When a control signal is applied to the first electrode E11 and a transverse electric field is generated between the first strip electrode E11A and the second strip electrode E11B, the long axes of the liquid crystal molecules LCM are oriented along the electric field (if the liquid crystal has positive dielectric anisotropy). As a result, as shown in FIG. 6B , regions are formed in which the liquid crystal molecules LCM stand up above the first strip electrode E11A and the second strip electrode E11B, and regions are formed between the first strip electrode E11A and the second strip electrode E11B in which the liquid crystal molecules LCM are oriented obliquely along the electric field distribution. At this time, if the thickness D of the first liquid crystal layer LC1 is sufficiently large (10 μm or more), i.e., if the thickness D of the first liquid crystal layer LC1 is sufficiently large, the electric field generated by the first electrode E11 does not affect the second substrate S12 side, and the alignment state of the liquid crystal molecules LCM changes only on the first substrate S11 side. In other words, the liquid crystal molecules LCM on the second substrate S12 side are not affected by the electric field and maintain an unchanged alignment.

[0064] As shown in FIG. 6B , when a transverse electric field is generated between the first strip electrode E11A and the second strip electrode E11B, the liquid crystal molecules LCM are oriented in a convex arc shape with their long axes aligned along the direction of the electric field. In liquid crystals with dielectric anisotropy, the dielectric constant distribution also changes to an arc shape as the alignment state of the liquid crystal molecules LCM changes. When light enters from the first substrate S11 in this state, the polarized component parallel to the X-axis direction is diffused into an outgoing direction due to the dielectric constant distribution. The polarized component parallel to the X-axis direction is then rotated 90 degrees as it travels from the first substrate S11 to the second substrate S12. On the other hand, the polarized component parallel to the Y-axis direction is not affected by the dielectric constant distribution and enters the first liquid crystal layer LC1 without being diffused, and is then rotated 90 degrees as it travels from the first substrate S11 to the second substrate S12.

[0065] In this way, by orienting the liquid crystal molecules LCM in a predetermined direction and changing this orientation state using a transverse electric field, it is possible to diffuse a specific polarization component of incident light (widen the luminous intensity distribution). Note that while Figures 6A and 6B illustrate the effect of the first electrode E11 on the liquid crystal molecules LCM and incident light, the same applies to the effect of the second electrode E12 of the second substrate S12 on the first liquid crystal layer LC1. That is, on the second substrate S12 side, by generating a transverse electric field using the second electrode E12, it is possible to diffuse a polarization component parallel to the Y-axis direction (widen the luminous intensity distribution).

[0066] Fig. 7A is a perspective view showing a first configuration of the lighting device 100 according to this embodiment. As described with reference to Fig. 4A , the lighting device 100 according to the first configuration has a light-blocking element 104 and a liquid crystal light control element 120 arranged in this order from the light source 102 side. The light-blocking element 104 has the same configuration as the light-blocking element shown in Fig. 3. That is, the light-blocking element 104 has a configuration in which a first polarizing plate 1042 and a second polarizing plate 1046 are arranged with a liquid crystal panel 1044 sandwiched between them. The transmission polarization axes of the first polarizing plate 1042 and the second polarizing plate 1046 are arranged parallel to the Y-axis direction.

[0067] 7A , the liquid crystal panel 1044 constituting the light-blocking element 104 only shows the first substrate S01, the second substrate S02, and the liquid crystal layer LC01, and omits the common electrode COM, the drive electrode SE, the first alignment film AF01, the second alignment film AF02, etc. Note that in FIG. 7A , the alignment directions AD1 and AD2 of the first alignment film AF01 and the second alignment film AF02 are indicated by arrows. The alignment direction AD1 of the first alignment film (not shown) on the first substrate S01 side is the same as the Y-axis direction, and the alignment direction AD2 of the second alignment film (not shown) on the second substrate S02 side is the same as the X-axis direction.

[0068] The liquid crystal light control element 120 has a configuration similar to that of the liquid crystal light control element shown in FIG. 5 . Note that the strip-shaped pattern of the first electrode E11 extends in the X-axis direction, and the strip-shaped pattern of the second electrode E12 extends in the Y-axis direction. In FIG. 7A , other components of the first liquid crystal cell 1221, such as the first alignment film AL11 and the second alignment film AL12, are omitted. Note that in FIG. 7A , the alignment directions ALD1 and ALD2 of the first alignment film (not shown) and the second alignment film (not shown) of the first liquid crystal cell 1221 are indicated by arrows. The alignment direction ALD1 of the first alignment film is the same as the Y-axis direction, and the alignment direction ALD2 of the second alignment film (not shown) is the same as the X-axis direction.

[0069] Next, the operation of the lighting device 100 shown in Fig. 7A will be described. The lighting device 100 shown in Fig. 7A has an optical path in which light emitted from a light source 102 (not shown) passes through a light-blocking element 104 and then passes through a liquid crystal light control element 120 to be emitted to the outside. In Fig. 7A, the emission direction of the light (first polarization component PL1 and second polarization component PL2) emitted from the light source 102 (not shown) is indicated by an arrow pointing from the bottom to the top of the drawing.

[0070] 7A shows the case where the light-blocking element 104 is in the off state (light-blocking state). The first polarized component PL1 and the second polarized component PL2 are incident on the first polarizer 1042. The transmission polarization axis TA1 of the first polarizer 1042 is in the same direction as the Y-axis direction. Therefore, of the light incident on the first polarizer 1042, the first polarized component PL1 is transmitted and the second polarized component PL2 is absorbed. Note that, as described with reference to FIG. 3, when the first brightness enhancement film 1048A is provided, the second polarized component PL2 is reflected by the first brightness enhancement film 1048A.

[0071] The first polarized light component PL1 transmitted through the first polarizer 1042 enters the liquid crystal panel 1044. The first polarized light component PL1 entering the liquid crystal panel 1044 is rotated by 90 degrees due to the 90-degree twisted orientation of the liquid crystal molecules in the liquid crystal layer LC01 from the first substrate S01 to the second substrate S02, and transitions to a second polarized light component PL2. Because the transmission polarization axis of the second polarizer 1046 is oriented in the Y-axis direction, the second polarized light component PL2 emitted from the liquid crystal panel 1044 is absorbed by the second polarizer 1046. If a second brightness enhancement film 1048B is provided, the second polarized light component PL2 is reflected by the second polarizer 1046. Therefore, when the light-blocking element 104 is in the off state, the light emitted from the light source 102 is blocked and does not exit to the outside.

[0072] Figure 7B shows a state in which the light-shielding element 104 is in the on state (transmitting state), a control signal is applied to the first electrode E11 and the second electrode E12 of the liquid crystal light control element 120 (on state), and a transverse electric field is generated in a direction parallel to the alignment directions ALD1 and ALD2.

[0073] When the light-blocking element 104 is in the on state, the first polarized light component PL1 incident on the liquid crystal panel 1044 is not optically rotated by the liquid crystal layer LC01 and passes through the second polarizer 1046 as is. The first polarized light component PL1 incident on the liquid crystal light control element 120 is incident on the first liquid crystal cell 1221 constituting the liquid crystal light control element 120. In the first liquid crystal cell 1221, on the first substrate S11 side, the liquid crystal molecules LCM form an arc-shaped dielectric constant portion due to an electric field parallel to the Y-axis direction (alignment direction ALD1). The polarization axis direction of the first polarized light component PL1 incident on the first liquid crystal cell 1221 is parallel to the Y-axis direction (alignment direction ALD1). Therefore, the first polarized light component PL1 is diffused in the Y-axis direction due to the dielectric constant distribution formed by the liquid crystal molecules LCM. As the first polarized component PL1 passes through the first liquid crystal layer LC1 from the first substrate S11 to the second substrate S12, it is rotated by 90 degrees by the liquid crystal molecules LCM, which are aligned with a 90-degree twist, and transitions to the second polarized component PL2. On the second substrate S12 side, the liquid crystal molecules LCM form arc-shaped dielectric constant distributions due to an electric field generated in a direction parallel to the X-axis direction (alignment direction ALD2). Because the polarization axis of the second polarized component PL2 is parallel to the X-axis direction (alignment direction ALD2), it is diffused in the X-axis direction by the dielectric constant distribution formed by the liquid crystal molecules LCM. The second polarized component PL2 then exits the first liquid crystal cell 1221.

[0074] In this way, the light emitted from the light source 102 passes through the light-shielding element 104 as the first polarization component PL1, is diffused in the X-axis direction by the liquid crystal light control element 120, transitions to the second polarization component PL2, and is then diffused in the X-axis direction and emitted.

[0075] 7B shows a state in which a control signal is applied to both the first electrode E11 and the second electrode E12 of the liquid crystal light control element 120, but the control signal applied to the liquid crystal light control element 120 is not limited to this example. The control signal applied to the liquid crystal light control element 120 may be applied to only one of the first electrode E11 and the second electrode E12, or may not be applied to both.

[0076] 8A is a perspective view showing a second configuration of the lighting device 100 according to this embodiment. In the second configuration, the liquid crystal light control element 120 is composed of two liquid crystal cells, a first liquid crystal cell 1221 and a second liquid crystal cell 1222. The first liquid crystal cell 1221 and the second liquid crystal cell 1222 are arranged to overlap each other so that light enters from the first liquid crystal cell 1221 side and exits from the second liquid crystal cell 1222 side. The configuration of the first liquid crystal cell 1221 is the same as the configuration shown in FIG. 7A. In the second liquid crystal cell 1222, the alignment direction ALD3 of the first alignment film on the first substrate S21 side is oriented in the X-axis direction, and the alignment direction ALD4 of the second alignment film on the second substrate S22 side is oriented in the Y-axis direction.

[0077] Fig. 8A shows a case where the light-blocking element 104 is in an off state. In this case, the operation of the lighting device 100 is the same as the example shown in Fig. 7A, and since the light emitted from the light source 102 is blocked, no light is emitted to the outside.

[0078] 8B shows a state in which the light-blocking element 104 is in an on state and a control signal is applied to the electrodes of the first liquid crystal cell 1221 and the second liquid crystal cell 1222 of the liquid crystal light control element 120. When the light-blocking element 104 is in an on state, a first polarization component PL1 of the polarization components emitted from the light source 102 (not shown) is emitted from the light-blocking element 104. The first polarization component PL1 incident on the liquid crystal light control element 120 is diffused in the Y-axis direction on the first substrate S11 side of the first liquid crystal cell 1221, rotated by 90 degrees in the first liquid crystal layer LC1, converted to a second polarization component PL2, and then diffused in the X-axis direction on the second substrate S12 side. The second polarization component PL2 incident on the second liquid crystal cell 1222 is diffused in the X-axis direction on the first substrate S21 side, rotated 90 degrees in the second liquid crystal layer LC2 and transitioned to the first polarization component PL2, and then diffused in the Y-axis direction on the second substrate D22 side and emitted.

[0079] Thus, according to the second configuration of the lighting device 100, the first polarization component PL1 emitted from the light-shielding element 104 is diffused twice in the X-axis direction and the Y-axis direction, and rotated twice at an angle of 90 degrees, and is emitted in the state of the first polarization component PL1.

[0080] 8B shows a case where a control signal is applied to all of the electrodes of the first liquid crystal cell 1221 and the second liquid crystal cell 1222, but the operation of the lighting device 100 according to the second configuration is not limited to this example. For example, a control signal may be applied only to the second electrode E12 of the first liquid crystal cell 1221 and the first electrode E21 of the second liquid crystal cell 1222 to operate the lighting device 100 so that the polarized light wave is diffused twice in the X-axis direction, or a control signal may be applied only to the first electrode E11 of the first liquid crystal cell 1221 and the first electrode E21 of the second liquid crystal cell 1222 to operate the lighting device 100 so that the polarized light wave is diffused once in each of the X-axis direction and the Y-axis direction.

[0081] 9A is a perspective view showing a third configuration of the lighting device 100 according to this embodiment. Fig. 9A shows a configuration in which the position and direction of the transmission axis of the second polarizer 1046 are changed compared to the configuration of the lighting device 100 according to the first configuration. Specifically, the lighting device 100 according to the third configuration has a configuration in which the second polarizer 1046 is disposed outside the liquid crystal light control element 120. Furthermore, the transmission polarization axis of the second polarizer 1046 is oriented in the X-axis direction.

[0082] 9A shows a state in which the light-blocking element 104 is in an off state and no control signal is applied to the first substrate E11 and second electrode E12 of the first liquid crystal cell 1221. This figure also shows a state in which no control signal is applied to the first electrode E11 and second electrode E12 of the first liquid crystal cell 1221. In this state, the first polarized component PL1 transmitted through the first polarizer 1042 is rotated 90 degrees by the light-blocking element 104, converted to the second polarized component PL2, and then enters the first liquid crystal cell 1221. In the first liquid crystal cell 1221, the second polarized component PL2 is rotated 90 degrees by the first liquid crystal layer LC1 and converted to the first polarized component PL1. However, because neither the first electrode E11 nor the second electrode E12 generates a transverse electric field, no diffusion occurs. Because the transmission axis of the second polarizer 1046 is oriented in the X-axis direction, the first polarized component PL1 emitted from the first liquid crystal cell 1221 is absorbed rather than transmitted. Therefore, the light emitted from the light source 102 is blocked.

[0083] 9B shows a state in which the light-blocking element 104 is on and a control signal is applied to the first electrode E11 and the second electrode E12 of the first liquid crystal cell 1221. Under this condition, the first polarized light component PL1 transmitted through the first polarizer 1042 is not rotated by the light-blocking element 104 and is incident on the first liquid crystal cell 1221. The first polarized light component PL1 is diffused in the Y-axis direction on the first substrate S11 side, rotated 90 degrees by the first liquid crystal layer LC1 to become the second polarized light component PL2, and then diffused in the X-axis direction on the second substrate S12 side. Because the transmission axis of the second polarizer 1046 is oriented in the X-axis direction, the second polarized light component PL2 is transmitted through the second polarizer 1046 and emitted.

[0084] In this way, in the lighting device 100 of the third configuration, the first polarization component PL1 is diffused in the Y-axis direction by the liquid crystal light control element 120, rotated by 90 degrees by the first liquid crystal cell 1221 to become the second polarization component PL2, and then diffused in the X-axis direction and emitted.

[0085] 9B shows a case where a control signal is applied to both the first electrode E11 and the second electrode E12 of the first liquid crystal cell 1221, but the operation of the illumination device 100 according to the third configuration is not limited to this example. For example, a control signal may be applied to only one of the first electrode E11 and the second electrode E12 to cause the illumination device 100 to operate so that the polarized light wave is diffused in either the X-axis direction or the Y-axis direction.

[0086] 10A is a perspective view showing a fourth configuration of the lighting device 100 according to the present embodiment. Fig. 10A differs from the lighting device 100 according to the third configuration in that the liquid crystal light control element 120 is composed of a first liquid crystal cell 1221 and a second liquid crystal cell 1222, and that the transmission polarization axis TA2 of the second polarizer 1046 is arranged in the same direction as the transmission polarization axis TA1 of the first polarizer 1042.

[0087] 10A shows a state in which the light-blocking element 104 is in an off state and no control signal is applied to the liquid crystal light control element 120. As described with reference to FIG. 9A , the first polarized component PL1 transmitted through the first polarizer 1042 is rotated by 90 degrees by the liquid crystal panel 1044 and converted into the second polarized component PL2. The second polarized component PL2 output from the light-blocking element 104 enters the first liquid crystal cell 1221 of the liquid crystal light control element 120. Because no control signal is applied to the first electrode E11 and the second electrode E12 of the first liquid crystal cell 1221, the second polarized component PL2 is not diffused and is rotated by 90 degrees by the first liquid crystal layer LC1 and converted into the first polarized component PL1. The first polarized component PL1 output from the first liquid crystal cell 1221 enters the second liquid crystal cell 1222. Because no control signal is applied to the first electrode E21 and the second electrode E22 of the second liquid crystal cell 1222, the first polarized component PL2 is not diffused, but is rotated by 90 degrees in the second liquid crystal layer LC2 to become the second polarized component PL2, which then enters the second polarizer 1046. The transmission polarization axis of the second polarizer 1046 is oriented in the Y-axis direction and intersects with the second polarized component PL2. Therefore, the second polarized component PL2 emitted from the liquid crystal light control element 120 is absorbed by the second polarizer 1046 and is not emitted to the outside. In other words, the light emitted from the light source 102 is blocked.

[0088] 10B shows a state in which the light-blocking element 104 is in an on state and control signals are applied to the first electrode E11 and the second electrode E12 of the first liquid crystal cell 1221 and the first electrode E21 and the second electrode E22 of the second liquid crystal cell 1222. In this state, the first polarized light component PL1 transmitted through the first polarizer 1042 is not rotated by the light-blocking element 104 and is incident on the first liquid crystal cell 1221. The first polarized light component PL1 is diffused in the Y-axis direction on the first substrate S11 side, rotated 90 degrees by the first liquid crystal layer LC1, converted into the second polarized light component PL2, and diffused in the X-axis direction on the second substrate S12 side. The second polarized light component PL2 emitted from the first liquid crystal cell 1221 is incident on the second liquid crystal cell 1222. The second polarized component PL2 is diffused in the X-axis direction on the first substrate S21 side, rotated by 90 degrees in the second liquid crystal layer LC2 to become the first polarized component PL1, and then diffused in the Y-axis direction on the second substrate S22 side. Because the transmission axis of the second polarizer 1046 is oriented in the Y-axis direction, the second polarized component PL2 passes through the second polarizer 1046 and is emitted.

[0089] Thus, according to the lighting device 100 of the fourth configuration, the first polarization component PL1 emitted from the light-shielding element 104 is diffused twice in the X-axis direction and the Y-axis direction as it passes through the liquid crystal light control element 120, and is rotated twice at an angle of 90 degrees, and is emitted in the state of the first polarization component PL1.

[0090] 10B shows a case where a control signal is applied to all of the electrodes of the first liquid crystal cell 1221 and the second liquid crystal cell 1222, but the operation of the lighting device 100 according to the fourth configuration is not limited to this example. For example, a control signal may be applied only to the second electrode E12 of the first liquid crystal cell 1221 and the first electrode E21 of the second liquid crystal cell 1222 to operate the lighting device 100 so that the polarized light wave is diffused twice in the X-axis direction, or a control signal may be applied only to the first electrode E11 of the first liquid crystal cell 1221 and the first electrode E21 of the second liquid crystal cell 1222 to operate the lighting device 100 so that the polarized light wave is diffused once in each of the X-axis direction and the Y-axis direction.

[0091] According to the lighting device 100 of this embodiment, not only can the light emitted from the light source 102 be irradiated as a spotlight by the shading element 104, but also light whose light distribution state has been controlled by the liquid crystal light control element 120 can be irradiated as a spotlight onto an arbitrarily selected area.

[0092] Third Embodiment This embodiment shows the configuration of a driving electrode provided in the light-shielding element 104.

[0093] FIG. 11A is a plan view showing the configuration of the light-blocking element 104 on the second substrate S02 side. The second substrate S02 is provided with a plurality of drive electrodes SE_01 to SE16. The drive electrodes SE_01 to SE_16 are arranged, for example, in a matrix. The second substrate S02 is also provided with a plurality of input terminals SEG01 to SEG16 for applying voltages to the drive electrodes SE_01 to SE_16. The drive electrodes SE_01 to SE_16 have, for example, a circular shape in plan view. The size of the drive electrodes SE is not limited, but may have a diameter of 1 mm to 100 mm, for example. The drive electrodes SE_01 to SE_16 may be the same size, or may be arranged so that drive electrodes of different sizes are mixed. While FIG. 11A shows a plurality of drive electrodes SE_01 to SE_16, the number of drive electrodes is not limited to the illustrated example and can be set as appropriate.

[0094] The size of each of the multiple drive electrodes SE_01 to SE_06 (diameter if circular, length of one side if rectangular, length of diagonal if polygonal) can be several millimeters to several tens of millimeters. For example, the multiple drive electrodes SE_01 to SE_06 can be circular with a diameter of 2 mm to 40 mm. Furthermore, the shape of the multiple drive electrodes SE_01 to SE_16 in a planar view is not limited to a circle and can be replaced with other shapes such as a rectangle, triangle, hexagon, or ellipse. While FIG. 11A illustrates an arrangement of 16 drive electrodes, there is no particular limitation on the number of drive electrodes SE. Furthermore, multiple input terminals SEG01 to SEG16 are provided for applying voltages to the multiple drive electrodes SE_01 to SE_16. The multiple input terminals SEG01 to SEG16 are provided corresponding to the multiple drive electrodes SE_01 to SE_16 and are connected by wiring.

[0095] 11B shows a cross-sectional structure of the light-blocking element 104 corresponding to the line A-B shown in FIG. 11A. A plurality of drive electrodes SE_01 to SE_16 (FIG. 11B shows drive electrodes SE_01 to SE_04) are provided on the second substrate S02 and are arranged to face the common electrode COM provided on the first substrate S01. A liquid crystal layer LC01 is provided between the plurality of drive electrodes SE_01 to SE_16 and the common electrode COM. A plurality of input terminals SEG01 to SEG16 are arranged in an outer region so as not to overlap with the common electrode COM. Control signals are input to the plurality of input terminals SEG01 to SEG16 from an external control circuit.

[0096] 3, when a voltage that changes the alignment state of the liquid crystal is applied between each of the drive electrodes SE_01 to SE_16 and the common electrode COM, that region changes to a transmissive mode, forming a region that transmits light emitted from the light source 102. As shown in FIG. 11A, when the shape of the drive electrode SE is circular, a circular spotlight can be emitted.

[0097] 11C and 11D show examples of drive signals for driving the light-blocking element 104. FIG. 11C shows, as an example, a drive signal that turns on the drive electrode SE_02 shown in FIG. 11B (transmission mode). Specifically, FIG. 11C shows the drive signal S-COM applied to the common electrode COM, the drive signal S-SE_02 applied to the drive electrode SE_02, and the voltage between the common electrode COM and the drive electrode SE_02 when the common electrode COM is viewed as a ground (GND) level. Pulse signals of opposite phases are input to the common electrode COM and the drive electrode SE_02. Such drive signals perform common inversion driving, in which the voltage level between the common electrode COM and the drive electrode SE_02 is inverted when the common electrode COM is viewed as a ground (GND) level.

[0098] 11D shows a drive signal that turns off the drive electrode SE_02 (light blocking mode). When the light blocking element 104 is driven in the light blocking mode, in-phase pulse signals are input as the drive signal S-COM applied to the common electrode COM and the drive signal S-SE_02 applied to the drive electrode SE_02. With such drive signals, when the common electrode COM is viewed as the ground (GND) level, the voltage levels between the common electrode COM and the drive electrode SE_02 become the same, and no potential difference occurs between the common electrode COM and the drive electrode SE_02.

[0099] 11C and 11D show drive signals applied to the common electrode COM and the drive electrode SE_02, but other drive electrodes can also be driven in the same way. That is, when a constant pulse signal is input to the common electrode COM, a drive signal that sets the drive electrodes SE_01 to SE_16 in a transmissive mode or a drive signal that sets the drive electrodes SE_01 to SE_16 in a light-blocking mode can be input to illuminate a specific area with a spotlight, and the illumination position of the spotlight can be moved within the illumination light illumination range.

[0100] The configuration shown in this embodiment can be applied to the light-shielding element 104 shown in the first and second embodiments, and the lighting device 100 can be configured using the light-shielding element 104 shown in this embodiment.

[0101] Fourth Embodiment This embodiment shows a configuration in which a light-shielding layer is added to the light-shielding element 104 shown in the first embodiment.

[0102] 12 shows a cross-sectional view of the light-shielding element 104 according to this embodiment. The light-shielding element 104 according to this embodiment has the same configuration as the light-shielding element 104 shown in the first embodiment (see FIG. 3), except that a light-shielding layer BM is provided. The following description will focus on the differences from the light-shielding element shown in the first embodiment.

[0103] The light-shielding layer BM is disposed in the region between the drive electrodes SE_01 to SE_03. The light-shielding layer BM is provided so as to fill the region between the drive electrodes SE_01 to SE_03. The light-shielding layer BM may be formed of a metal material or a resin material. As the metal material, it is preferable to use a metal material with low reflectance such as titanium (Ti), molybdenum (Mo), or a molybdenum-tungsten alloy (MoW). As the resin material, it is preferable to use a resin material containing a black pigment.

[0104] When the light-shielding layer BM is made of a resin material and has insulating properties, it may be formed in the same layer as the driving electrodes SE_01 to SE_03. On the other hand, when the light-shielding layer BM is made of a metal material, it is preferable that it be provided in a different layer from the driving electrodes SE_01 to SE_03, with the insulating layer IL01 sandwiched therebetween.

[0105] As described in the first embodiment, the light-blocking element 104 is an element that blocks light, and therefore can block light even if a light-blocking layer BM is not present in the region between the drive electrodes SE_01 to SE_03. However, by providing a light-blocking layer BM between the drive electrodes SE_01 to SE_03, it is possible to block light that passes through the region between the electrodes, and to suppress temperature rise in the second polarizer 1046. This can suppress deterioration of the second polarizer 1046. Furthermore, by using a light-blocking layer BM, it is possible to obtain the same effect as when a second brightness enhancement film is provided. Because the light-blocking layer BM can be built into the liquid crystal panel 1044, it is possible to make the light-blocking element 104 thinner than when a brightness enhancement film is used.

[0106] The configuration shown in this embodiment can be applied to the light-blocking element 104 shown in the first to third embodiments, and the lighting device 100 can be configured using the light-blocking element 104 shown in this embodiment.

[0107] Fifth Embodiment This embodiment shows an aspect in which the configuration of the drive electrodes is different from that of the light-shielding element shown in the third embodiment.

[0108] Fig. 13 shows the configuration of the drive electrodes SE (SE_01 to SE_09) of the light-blocking element 104 according to this embodiment. Fig. 13 shows a configuration in which a plurality of drive electrodes SE_01 to SE_09 are arranged in a matrix. Each of the plurality of drive electrodes SE_01 to SE_09 is formed by combining a plurality of sub-electrodes.

[0109] Focusing on the driving electrode SE_01, the driving electrode SE_01 is composed of a first sub-driving electrode SE011 and a second sub-driving electrode SE012. The second sub-driving electrode SE012 is provided so as to surround the first sub-driving electrode SE011. Furthermore, while the first sub-driving electrode SE011 is circular in plan view, the second sub-driving electrode SE012 has a polygonal (rectangular) shape that surrounds the circular electrode.

[0110] The first sub-drive electrode SE011 and the second sub-drive electrode SE12 are electrically isolated, and a drive voltage can be applied to each sub-drive electrode individually. Therefore, the first sub-drive electrode SE011 is connected to the input terminal SEG11, and the second sub-drive electrode SE012 is connected to the input terminal SEG12.

[0111] Such configurations of the sub-drive electrodes and input terminals are the same for the other drive electrodes SE_02 to SE_09.

[0112] 13, the illumination shape of the spotlight can be switched from a circular shape to a square shape (rectangle) in the same illumination area. Also, the area of ​​the illumination area of ​​the spotlight can be switched between large and small.

[0113] 13 shows a case where the first sub-drive electrode SE011 is circular and the second sub-drive electrode SE012 is angular (rectangular), but the configuration of the drive electrodes SE (SE_01 to SE_02) according to this embodiment is not limited to this combination. The first sub-drive electrode SE011 and the second sub-drive electrode SE012 can be combined with various shapes. For example, the first sub-drive electrode SE011 can be triangular in plan view, and the second sub-drive electrode SE012 can be hexagonal in plan view.

[0114] Fig. 14 shows another example of the driving electrodes SE (SE_01 to SE_02) according to this embodiment. Fig. 14 shows a configuration in which a plurality of driving electrodes SE_01 to SE_09 are arranged in a matrix. Each of the plurality of driving electrodes SE_01 to SE_09 is made up of a plurality of sub-electrodes arranged in a concentric circle.

[0115] Focusing on the driving electrode SE_01, the driving electrode SE_01 is composed of a first sub-driving electrode SE011, a second sub-driving electrode SE012, and a third sub-driving electrode SE013. The driving electrode SE_01 has a configuration in which the first sub-driving electrode SE011 is arranged at the center, and the second sub-driving electrode SE012 and the third sub-driving electrode SE013 are arranged concentrically around the first sub-driving electrode SE011.

[0116] The first sub-drive electrode SE011, the second sub-drive electrode SE012, and the third sub-drive electrode SE013 are electrically isolated, and a drive voltage can be applied to each sub-drive electrode individually. The first sub-drive electrode SE011 is connected to the input terminal SEG11, the second sub-drive electrode SE12 is connected to the input terminal SEG12, and the third sub-drive electrode SE013 is connected to the input terminal SE13.

[0117] Such configurations of the sub-drive electrodes and input terminals are the same for the other drive electrodes SE_02 to SE_09.

[0118] 14, the illumination range of the spotlight can be expanded or contracted in stages. Furthermore, by applying a driving voltage to the first sub-drive electrode SE011 and the third sub-drive electrode SE013 and not applying a driving voltage to the second sub-drive electrode SE012, it is possible to add shading to the brightness of the illumination area of ​​the spotlight.

[0119] 14 shows a case where the sub-drive electrodes SE (SE_01 to SE_09) are circular, the configuration of the drive electrodes SE (SE_01 to SE_02) according to this embodiment is not limited to this shape. For example, the shape of the sub-drive electrodes SE (SE_01 to SE_09) in a plan view can be various shapes such as a triangle, a rectangle, a hexagon, or an ellipse.

[0120] As described above, according to this embodiment, by configuring the drive electrode with sub-drive electrodes, it is possible to vary the illumination range and illumination shape of the spotlight. Note that although Figures 13 and 14 show a plurality of drive electrodes SE_01 to SE_09, the number of drive electrodes is not limited to the examples shown in the drawings and can be set as appropriate.

[0121] The configuration shown in this embodiment can be applied to the light-blocking element 104 shown in the first to fourth embodiments, and the lighting device 100 can be configured using the light-blocking element 104 shown in this embodiment.

[0122] Sixth Embodiment This embodiment shows an aspect in which the light-blocking element 104 is composed of a plurality of liquid crystal panels. The configuration of the liquid crystal panels in this embodiment is substantially the same as that shown in the first embodiment, but there is a difference in the arrangement of the drive electrodes. Below, the differences will be mainly described, and a description of the common parts will be omitted.

[0123] 15 shows the configuration of a light-blocking element 104 having a first liquid crystal panel 1044 A and a second liquid crystal panel 1044 B. This light-blocking element 104 has a structure in which the first liquid crystal panel 1044 A and the second liquid crystal panel 1044 B are stacked between a first polarizing plate 1042 and a second polarizing plate 1046.

[0124] The first liquid crystal panel 1044A includes a first substrate S01, a second substrate S02, a liquid crystal layer LC01 (not shown) between the first substrate S01 and the second substrate S02, a first alignment film on the first substrate S01 side, and a second alignment film (not shown) on the second substrate S02 side. The second liquid crystal panel 1044B includes a third substrate S03, a fourth substrate S04, a liquid crystal layer LC02 (not shown) between the third substrate S03 and the fourth substrate S04, a third alignment film on the third substrate S03 side, and a fourth alignment film (not shown) on the fourth substrate S04 side.

[0125] 15 shows, as an inset, the arrangement of the first drive electrodes SE_A provided on the second substrate S02A of the first liquid crystal panel 1044A and the arrangement of the second drive electrodes SE_B provided on the second substrate S04 of the second liquid crystal panel 1044B. A first common electrode COM (not shown) is provided opposite the first drive electrodes SE_A, and a second common electrode COM (not shown) is provided opposite the second drive electrodes SE_B. The first drive electrodes SE_A and the second drive electrodes SE_B are arranged in a matrix, and the second drive electrodes SE_B are arranged so as to overlap with the gaps (inter-electrode regions) between the first drive electrodes SE_A. This configuration allows for an increased density of the drive electrodes SE when the first liquid crystal panel 1044A and the second liquid crystal panel 1044B are stacked. Applying the light-blocking element 104 having such a configuration to the lighting device 100 can increase the degree of freedom in the spotlight irradiation position and the position to which the spotlight can be moved. In addition, by simultaneously driving adjacent drive electrodes SE in a transmissive mode, the spotlight irradiation range can be widened.

[0126] It should be noted that the liquid crystal panels constituting the light-blocking element 104 are not limited to a two-tier configuration. For example, as shown in Fig. 16, four liquid crystal panels 1044A, 1044B, 1044C, and 1044D may be stacked. In this case, too, the drive electrodes SE_A, SE_B, SE_C, and SE_D of each liquid crystal panel may be arranged so as to fill the gaps (inter-electrode regions), thereby further increasing the density of the drive electrodes and further increasing the degree of freedom in determining the spotlight irradiation position and the position to which the spotlight can be moved.

[0127] The configuration shown in this embodiment can be applied to the light-blocking element 104 shown in the first to fifth embodiments, and the lighting device 100 can be configured using the light-blocking element 104 shown in this embodiment.

[0128] Seventh Embodiment This embodiment shows an aspect in which the configuration of the light-blocking element 104 applied to the lighting device 100 is different from that of the first embodiment. In this embodiment, the liquid crystal panel constituting the light-blocking element 104 has each drive electrode driven by a transistor.

[0129] 17 shows the configuration of the first substrate S02 side of the liquid crystal panel 1044 that constitutes the light-blocking element 104. The second substrate S02 is provided with drive electrodes SE arranged in a matrix and switching elements SW arranged corresponding to each drive electrode SE. The switching elements SE are formed, for example, of thin film transistors (TFTs). The second substrate S02 is also provided with scanning signal lines SL and data signal lines DL. The scanning signal lines SL are connected to a scanning signal line drive circuit SLC, and the data signal lines DL are connected to a selector circuit DLC. A signal that selects the switching element SW to which data is written is input to the scanning signal line SL, and a drive signal that drives the drive electrode SE is input to the data signal line DL.

[0130] The size of each of the drive electrodes SE arranged in a matrix (the length of one side if rectangular, the length of the diagonal if polygonal, and the diameter if circular) can be several tens of micrometers to several hundreds of micrometers. For example, the shape of the drive electrodes SE can be rectangular, with the length of one side being 20 μm to 400 μm. Furthermore, the shape of the multiple drive electrodes SE in a planar view is not limited to rectangular, and can be other shapes such as triangular, hexagonal, circular, or elliptical.

[0131] The liquid crystal panel 1044 constituting the light-blocking element 104 shown in the first embodiment has a circuit configuration in which a drive voltage is applied to each drive electrode SE, but the liquid crystal panel 1044 according to this embodiment is active matrix driven, which allows the drive electrodes SE to be turned on and off at higher speeds and allows the spotlight irradiation position to move more smoothly. In addition, the spotlight irradiation shape (spot shape) can be made into various shapes such as a circle, a square, a rectangle, a triangle, a star, etc.

[0132] 18A shows an example in which the drive electrodes SE are arranged in a matrix in the row and column directions. In FIG. 18A, the drive electrodes SE in the on state (transmission mode) are shown as white, and the drive electrodes SE in the off state (light-blocking mode) are shown as hatched. As shown in FIG. 18A, by selecting a plurality of adjacent drive electrodes SE to be in the on state (transmission mode), the size of the spotlight illumination area and the illumination shape (spot shape) can be freely changed.

[0133] FIG. 18B shows an example in which the drive electrodes SE are arranged in a delta configuration. The configuration shown in FIG. 18B also allows the size of the spotlight illumination area and the illumination shape (spot shape) to be freely formed. FIG. 18C shows an example in which the drive electrodes SE are arranged in a close-packed hexagonal shape in a plan view. According to the drive electrode SE arrangement shown in FIG. 18C, when a plurality of drive electrodes SE are turned on to set a predetermined range to a transmission mode, the contour of the spot shape of the illuminated spotlight can be made smoother. FIG. 18D shows an example in which the hexagonal drive electrodes SE are further divided into six subsegments. The drive electrode SE configuration shown in FIG. 18D allows for the formation of a highly precise spot shape.

[0134] In the liquid crystal panel 1044 of this embodiment, the drive electrodes SE can be driven in an active matrix using switching elements SE, so the drive electrodes SE can be made highly precise without significantly increasing the number of wirings, and the spotlight can be moved smoothly, forming an illumination shape with a smooth curve.

[0135] The configuration shown in this embodiment can be applied to the light-shielding element 104 shown in the first and second embodiments, and the lighting device 100 can be configured using the light-shielding element 104 shown in this embodiment.

[0136] 100: lighting device, 102: light source, 104: light-shielding element, 1042: first polarizing plate, 1044: liquid crystal panel, 1044A: first liquid crystal panel, 1044B: second liquid crystal panel, 1044C: third liquid crystal panel, 1044D: fourth liquid crystal panel, 1046: second polarizing plate, 1048A: first brightness enhancement film, 1048B: second brightness enhancement film, 106: light-shielding plate, 107: optical system, 108: reflector, 120: liquid crystal light control element, 1221: first liquid crystal cell, 1222: second liquid crystal cell, 200: irradiation surface, AF01: first alignment film, AF02: second alignment film, AL11: first alignment film, AL12: second alignment film, ALD1, ALD2: alignment direction, BM: light-shielding layer, COM: common electrode, DL: data signal line, DLC: selector circuit, E11, E21: first electrode, E12, E22: second electrode E, E11A: first strip-shaped electrode, E11B: second strip-shaped electrode, E12A: third strip-shaped electrode, E12B: fourth strip-shaped electrode, IL1: insulating layer, LC01: liquid crystal layer, LC1: first liquid crystal layer, LC2: second liquid crystal layer, LCM: liquid crystal molecule, S01: first substrate, S02: second substrate, S11: first substrate, S12: second substrate, SE: drive electrode, SE_01: first drive electrode, SE_02: second drive electrode, SE_03: third drive electrode, SG, SG_1: segment, SL: scanning signal line, SLC: scanning signal line drive circuit, SW: switching element, TA1, TA2: transmission polarization axis

Claims

1. An illumination device comprising: a light source for illuminating a target space; and a shading element arranged on the optical path of light emitted from the light source, wherein the shading element includes: a first liquid crystal panel including a first substrate, a second substrate facing the first substrate, and a first liquid crystal layer between the first substrate and the second substrate; and a first polarizing plate and a second polarizing plate arranged in a crossed Nicol or parallel Nicol configuration on either side of the first liquid crystal panel, wherein the first liquid crystal panel has a first common electrode and a plurality of first drive electrodes, and wherein the shading element is controlled such that each of the plurality of first drive electrodes is individually switched between a shading mode in which the light from the light source is blocked and a transmission mode in which the light from the light source is transmitted.

2. The lighting device according to claim 1, wherein the light-shielding element forms a light-shielding region by controlling the plurality of first drive electrodes to a light-shielding mode, and forms a transmissive region within the light-shielding region by controlling at least one of the plurality of first drive electrodes to a transmissive mode.

3. The lighting device according to claim 1, further comprising a second liquid crystal panel including a third substrate, a fourth substrate opposing the third substrate, and a second liquid crystal layer between the third substrate and the fourth substrate, wherein the second liquid crystal panel has a second common electrode and a plurality of second drive electrodes, wherein the first liquid crystal panel and the second liquid crystal panel are arranged in an overlapping manner between the first polarizer and the second polarizer, wherein the plurality of second drive electrodes are arranged to overlap with regions between the plurality of first electrodes, and wherein the light-shielding elements are controlled so that the plurality of first drive electrodes and the plurality of second drive electrodes are each individually between a light-shielding mode in which the light of the light source is blocked and a transmission mode in which the light of the light source is transmitted.

4. The lighting device described in claim 3, wherein the light-shielding element forms a first light-shielding region by controlling the plurality of first driving electrodes to a light-shielding mode, forms a first transparent region within the first light-shielding region by controlling at least one of the plurality of first driving electrodes to a transparent mode, forms a second light-shielding region by controlling the plurality of second driving electrodes to a light-shielding mode, and forms a second transparent region adjacent to the first transparent region by controlling at least one of the plurality of second driving electrodes to a transparent mode within the second light-shielding region.

5. The lighting device according to claim 1, wherein the light blocking element has a transistor connected to each of the first drive electrodes arranged in a matrix.

6. The lighting device according to claim 5, wherein the light-shielding element is capable of controlling each of the plurality of first drive electrodes individually to the light-shielding mode and the transmission mode, and of expanding and contracting a range of the plurality of first drive electrodes that is controlled to the transmission mode.

7. The lighting device of claim 1 or 3, further comprising: a first brightness enhancement film disposed on a surface of the first polarizer opposite the first substrate; and a second brightness enhancement film disposed between the second substrate and the second polarizer.

8. The lighting device according to claim 1 or 3, wherein each of the plurality of drive electrodes is divided into a plurality of regions.

9. The lighting device according to claim 1 or 3, wherein the liquid crystal material forming the first liquid crystal layer is a twisted nematic liquid crystal.

10. The lighting device according to claim 1 or 3, characterized in that it comprises a pair of substrates arranged opposite to each other and a liquid crystal layer between the pair of substrates, and further comprises a liquid crystal light control element that controls the diffusion direction of light emitted from a light source, the liquid crystal light control element being arranged to overlap the light-shielding element.

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