Dimmer

Abstract

To suppress deterioration of the external appearance of a dimmer due to sagging of a polarizing portion.SOLUTION: A dimmer D includes a first outer frame 11, a second outer frame 25, an intermediate frame 41, a first polarizing unit 51, and a second polarizing unit 52. The intermediate frame 41, to which the second polarizing unit 52 is fixed, is moved vertically relative to the first outer frame 11, to which the first polarizing unit 51 is fixed, thereby adjusting a degree of light transmission. A pair of intermediate main frame portions 42 of the intermediate frame 41 have protrusions that protrude toward a pair of first outer main frame portions 12 (rear side) of the first outer frame 11. A guide portion 17 of each first outer main frame portion 12 protrudes toward the intermediate main frame portions 42 (front side) and engages the protrusions from an inner side in a left-right direction, guiding vertical movement of the protrusions. At least one of the protrusions is configured by an inclined protrusion 44 that is inclined in front-rear and left-right directions so as to be positioned outward in the left-right direction toward the first outer main frame portion 12 (rear side).SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a light control device. [Background technology]

[0002] A light control device is known that adjusts the degree of light transmission by utilizing the optical properties of polarized light. Patent Document 1, for example, describes a light control device that includes a pair of rollers spaced apart from each other in a direction perpendicular to the front-to-rear direction, and a loop-shaped polarizing film stretched across the pair of rollers. The front-to-rear direction is the direction in which the light control device faces the user. Tension is applied to the polarizing film by the pair of rollers. The polarizing film has a first polarizing section and a second polarizing section, each having a polarization axis, facing each other in the front-to-rear direction, between the pair of rollers.

[0003] In the light control device, the first and second polarizing units move in opposite directions along the direction in which the pair of rollers are arranged, as the pair of rollers rotate, adjusting the degree of light transmission through the first and second polarizing units. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-61351 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the case of a light control device in which the polarizing film is not stretched over a pair of rollers, the following concern arises. For example, such a light control device includes a polarizing film having a first polarizing section and a second polarizing section that are provided independently of each other. In this light control device, at least one of the first polarizing section and the second polarizing section is moved relative to the other in the arrangement direction.

[0006] The concern is that it is difficult to maintain appropriate tension on the moving polarizing section of the first and second polarizing sections. If the first and second polarizing sections are not properly tensioned, they will sag. This sagging degrades the appearance of the light control device.

[0007] In particular, when the distance between the first polarizing unit and the second polarizing unit in the front-to-rear direction is narrow, if the loose part of the first polarizing unit or the second polarizing unit moves, the first polarizing unit and the second polarizing unit will rub against each other, and at least one of the first polarizing unit and the second polarizing unit will wear out, further deteriorating the appearance of the light control device. [Means for solving the problem]

[0008] Various aspects of the light control device for solving the above problems will be described below. [Aspect 1] When the direction facing a user is defined as a front-to-rear direction, the display device comprises: a first outer frame having a pair of first outer main frame parts extending in a first direction perpendicular to the front-to-rear direction and a second direction perpendicular to the first direction, while being spaced apart from each other in the first direction; a second outer frame having a pair of second outer main frame parts extending in the second direction, while being spaced apart from each other in the first direction, and being disposed in the front-to-rear direction of the first outer frame; a middle frame having a pair of middle main frame parts extending in the second direction between the first outer main frame part and the second outer main frame part, while being spaced apart from each other in the first direction; and first and second polarizing parts made of films each having a polarization axis and facing each other in the front-to-rear direction, wherein both ends of the first polarizing part in the first direction are fixed to the pair of first outer main frame parts. a dimming device in which both end portions in the first direction of the second polarization unit are fixed to a pair of central frame portions, and the central frame is moved in the second direction relative to the first outer frame to adjust the degree of light transmission in the first polarization unit and the second polarization unit, wherein each central frame portion has a protrusion that protrudes toward the first outer frame portion in the front-to-rear direction, and each first outer frame portion has a guide portion that protrudes toward the central frame portion in the front-to-rear direction, engages with the protrusion from the inside in the first direction, and guides movement of the protrusion in the second direction, and at least one of the protrusions is configured as an inclined protrusion that is inclined with respect to the front-to-rear direction and the first direction so as to be positioned more outward in the first direction as it approaches the first outer frame portion in the front-to-rear direction.

[0009] According to the above configuration, the protrusions of each central frame portion engage with the guide portions located on the inside in the first direction. The second polarization unit fixed to the pair of central frame portions is movable together with the central frame in a second direction relative to the first outer frame. When the second polarization unit moves in the second direction, the movement of each protrusion in the second direction is guided by the guide portion.

[0010] Here, the pair of protrusions, which are constituted by the inclined protrusions, are inclined with respect to the front-rear direction and the first direction so that they are positioned further outward in the first direction as they approach the first outer main frame portion in the front-rear direction. This inclined protrusion engages with the guide portion from the outside in the first direction, causing tension to act on the second polarization portion, pulling it outward in the first direction. Therefore, it is possible to continuously apply tension outward in the first direction to the second polarization portion regardless of its position in the second direction. This tension makes the second polarization portion less likely to sag. This reduces deterioration in the appearance of the light control device due to sagging.

[0011] Furthermore, even if the distance between the first polarizing unit and the second polarizing unit in the front-to-rear direction is narrow, the phenomenon of the loose second polarizing unit rubbing against the first polarizing unit as it moves is less likely to occur. Since wear caused by rubbing is suppressed, deterioration of the appearance of the light control device due to wear is also suppressed.

[0012] Furthermore, in the light control device, the second polarization unit attempts to shrink inward in the first direction against the tension, and the pair of central frame units are pulled inward in the first direction. Therefore, as described above, a force acts on the central frame toward the second outer frame in the front-to-rear direction via the inclined protrusions that are inclined relative to the front-to-rear direction and the first direction. As a result, it is possible to maintain a small and appropriate distance between the second polarization unit and the first polarization unit. This further reduces the likelihood of the second polarization unit rubbing against the first polarization unit as it moves.

[0013] [Aspect 2] The middle frame has a pair of middle connecting frame portions extending in the first direction while spaced apart from each other in the second direction, and each middle connecting frame portion connects the ends of the pair of middle main frame portions on the same side in the second direction, in the dimming device described in [Aspect 1].

[0014] According to the above configuration, the middle frame has a rectangular ring shape. When an operating load is applied to one of the middle main frame sections to move the middle frame in the second direction, the operating load is transmitted to the other middle main frame section via both middle connecting frame sections. Moreover, the distance between the pair of middle main frame sections is regulated by the pair of middle connecting frame sections. This distance is the same or approximately uniform at any point in the second direction.

[0015] Therefore, the other central frame portion can be moved in the second direction to the same extent as the one central frame portion to which the operating load is applied, making it easy to maintain the second polarization portion in a tensed state in the first direction regardless of its position in the second direction.

[0016] [Aspect 3] The middle frame is a dimming device described in [Aspect 1], wherein the middle frame has a single middle connecting frame portion that extends in the first direction and connects only one end of the pair of middle main frame portions in the second direction.

[0017] When the inclined protrusion engages with the guide portion from the outside in the first direction, a frictional force is generated between them. In the above configuration in which a single central connecting frame part connects only one end of a pair of central main frame parts, the frictional force is greatest near the central connecting frame part in the second direction. This frictional force decreases as the distance from the central connecting frame part increases in the second direction. This is because the other end of the pair of central main frame parts is not connected by the central connecting frame part.

[0018] Therefore, when manufacturing the light control device, the load required to push the middle frame toward the first outer frame to engage the inclined protrusion with the guide part is reduced, improving workability. Also, when using the light control device, the operating load applied to the middle frame to move it in the second direction is lighter, making it easier to operate.

[0019] [Aspect 4] The light control device according to any one of [Aspect 1] to [Aspect 3], wherein the second direction is the vertical direction, and further includes an elastic member that elastically biases the middle frame upward. According to the above configuration, a frictional force is generated between the guide portion and the inclined protrusion that engages with the guide portion from the outside in the first direction. Moreover, the second polarization portion attempts to contract inward in the first direction against the tension. The pair of central frame portions are pulled inward in the first direction. This further increases the frictional force.

[0020] Here, when the second direction is set to the up-down direction, a downward force acts on the middle frame and the second polarization unit fixed thereto due to their weight (their own weight). Therefore, in order to move the middle frame and the second polarization unit upward, it is necessary to apply an upward load that is large enough to overcome the frictional force and the downward force.

[0021] In this regard, with the above configuration, an upward elastic biasing force of the elastic member acts on the middle frame. By applying a small upward operating load corresponding to this elastic biasing force, it is possible to move the middle frame and the second polarization unit upward. In other words, the operating load applied when moving the middle frame and the second polarization unit upward becomes lighter, making the operation easier.

[0022] [Aspect 5] The middle frame includes a middle connecting frame portion that extends in the first direction and connects at least one of the ends of a pair of the middle main frame portions in the vertical direction, and the elastic member connects the middle connecting frame portion to the first outer frame or the second outer frame, in a dimming device described in [Aspect 4].

[0023] According to the above configuration, the elastic force of the elastic member is transmitted to the central connecting frame portion connected to the elastic member. This elastic force is transmitted to the pair of central main frame portions via the central connecting frame portion to the same extent. Therefore, when an operating load is applied in the vertical direction, the central frame moves in the vertical direction while applying an appropriate tension to the second polarization portion. [Effects of the Invention]

[0024] According to the present invention, it is possible to suppress deterioration in the appearance of the light control device due to sagging of the polarizing section. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a front view of a light control device according to the first embodiment. [Figure 2] FIG. 2 is an exploded perspective view showing the layer structure of the first polarizing unit in the first embodiment. [Figure 3] FIG. 3 is an exploded perspective view showing the layer structure of the second polarizing section in the first embodiment. [Figure 4] FIG. 4 is a partial cross-sectional view showing the layer structure of the polarizing region in the first embodiment. [Figure 5] FIG. 5 is an explanatory diagram showing the pattern of polarization axes in the polarizing regions of the first polarizing layer in the first embodiment. [Figure 6] FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 1, with some parts omitted. [Figure 9] FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 1 with some parts omitted. [Figure 10] FIG. 10 is a cross-sectional view taken along line 10-10 in FIG. 1 with some parts omitted. [Figure 11] Figure 11(A) is an explanatory diagram showing the effect of a second polarizing layer with a narrow gap between it and the first polarizing layer when viewed from diagonally above the front, and Figure 11(B) is an explanatory diagram showing the effect of a second polarizing layer with a wide gap between it and the first polarizing layer when viewed from diagonally above the front. [Figure 12] FIG. 12 is a partial cross-sectional view illustrating how the first polarizing unit is fixed to the first outer frame during the manufacture of the light control device according to the first embodiment. [Figure 13]FIG. 13 is a partially exploded cross-sectional view showing a state in which the middle frame is being assembled to the first outer frame together with the second outer frame during the manufacture of the light control device in the first embodiment. [Figure 14] FIG. 14 is a front view showing the light control device of the second embodiment. [Figure 15] FIG. 15 is a diagram corresponding to FIG. 9 and is a partial cross-sectional view showing a modified example of the fixing structure of the first polarizing unit to the first outer frame. [Figure 16] FIG. 16 is a diagram corresponding to FIG. 5, and is an explanatory diagram showing an example of a modified pattern of the polarization axes in the polarizing regions of the first polarizing layer. [Figure 17] FIG. 17 is an explanatory diagram showing a modified example of the pattern of polarization axes in the polarizing regions of the first polarizing layer, which is different from that shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0026] (First embodiment) Hereinafter, a first embodiment of the light control device will be described with reference to FIGS. In the following description, to specify directions, the direction of the dimming device D facing the user U is referred to as the front-rear direction, as shown in Figs. 6 and 7. In the front-rear direction, the side closer to the user U is referred to as the front side, and the side farther from the user U is referred to as the rear side. The vertical direction is referred to as the up-down direction. As shown in Fig. 8, the direction perpendicular to the front-rear direction and the up-down direction is referred to as the left-right direction. In the first embodiment, the left-right direction corresponds to the first direction in the claims. The up-down direction corresponds to the second direction in the claims.

[0027] Furthermore, with regard to the front-to-back, up-down, and left-to-right directions, the center of gravity of the dimming device D is used as the reference, and the side closer to this center of gravity is sometimes referred to as the "inside" or "inner side," and the side away from the center of gravity is sometimes referred to as the "outside" or "outer side."

[0028] 6 to 8, the light control device D includes a first outer frame 11, a second outer frame 25, an intermediate frame 41, a first polarizing section 51, a second polarizing section 52, and an elastic member 65. Next, each part constituting the light control device D will be described.

[0029] <First outer frame 11> The first outer frame 11 comprises a pair of first outer main frame portions 12 and a single first outer connecting frame portion 19. The pair of first outer main frame portions 12 extend in the up-down direction while being spaced apart from each other in the left-right direction.

[0030] Each first outer main frame portion 12 includes a rear wall portion 13 and a first side wall portion 14. A portion of each rear wall portion 13 is flat and extends in the up-down and left-right directions. Each first side wall portion 14 protrudes forward from an inner end portion of each rear wall portion 13 in the left-right direction. As shown in Figures 9 and 10, bulging portions 15 that bulge forward are formed in multiple locations on the outer side of each rear wall portion 13 in the left-right direction, spaced apart from each other in the up-down direction. A locking hole 16 that penetrates in the front-to-rear direction is formed in the front end portion of each bulging portion 15.

[0031] In each rear wall 13, a guide portion 17 is formed between the first side wall portion 14 and the bulge portion 15. Each guide portion 17 is plate-shaped extending in the front-rear and up-down directions, and is formed at multiple locations on the rear wall 13 that are spaced apart from each other in the up-down direction. Each guide portion 17 is reinforced by a reinforcing rib 18 provided between the guide portion 17 and the rear wall 13.

[0032] As shown in Figures 6 and 7, the first outer connecting frame portion 19 extends in the left-right direction and connects only the upper ends of a pair of first outer main frame portions 12 in the up-down direction. The first outer frame 11 configured in this way has an inverted U-shape when viewed from the front-to-back direction. A recess 21 that is open on the front and bottom surfaces is formed in the lower part of the first outer connecting frame portion 19. A spring accommodating chamber 22 that penetrates in the front-to-back direction is formed in the lower part of the first outer connecting frame portion 19, behind the recess 21.

[0033] <Second outer frame 25> 1 and 6 to 8, the second outer frame 25 includes a pair of second outer main frame portions 26 and a single second outer connecting frame portion 33. The pair of second outer main frame portions 26 extend in the up-down direction while being spaced apart from each other in the left-right direction. The second outer frame 25 is disposed in front of the first outer frame 11.

[0034] Each second outer main frame portion 26 includes a front wall portion 27, a protrusion portion 28, and a second side wall portion 29. The front wall portion 27 is flat and extends in the left-right and up-down directions. Each protrusion portion 28 protrudes rearward from an inner end portion of the front wall portion 27 in the left-right direction. Each protrusion portion 28 is spaced forward from the first side wall portion 14. Each second side wall portion 29 protrudes rearward from an outer end portion of the front wall portion 27 in the left-right direction. Each second side wall portion 29 contacts or is close to an outer end portion of the rear wall portion 13 in the left-right direction. As shown in FIG. 9 , each front wall portion 27 has a locking claw 31 protruding rearward at a location forward of the locking hole 16. Each locking claw 31 is inserted into the corresponding locking hole 16 and locked to the bulge portion 15, thereby connecting the second outer frame 25 to the first outer frame 11. In this connected state, a main storage section 32 with an open lower end is formed between the second outer frame 25 and the first outer frame 11. The upper end and the outer ends in the left-right direction of the main storage section 32 are both closed.

[0035] 1, 6, and 7, the second outer connecting frame part 33 extends in the left-right direction. A connecting accommodating part 34 is formed between the second outer connecting frame part 33 and the first outer connecting frame part 19, in a state including the recess 21.

[0036] The second outer connecting frame portion 33 connects only the upper ends of the pair of second outer main frame portions 26 in the up-down direction. The second outer frame 25 configured in this way has an inverted U-shape when viewed from the front-to-rear direction.

[0037] The front surface 35 of the second outer frame 25 constitutes a part of the design surface of the light control device D. <Middle frame 41> 1 and 6 to 8, the middle frame 41 includes a pair of middle main frame portions 42 and a single middle connecting frame portion 46. The pair of middle main frame portions 42 extend in the up-down direction between the first outer main frame portion 12 and the second outer main frame portion 26, while being spaced apart from each other in the left-right direction.

[0038] As shown in FIG. 10 , each central frame portion 42 includes a main body portion 43 and a protrusion. The main body portion 43 has a flat plate shape extending in the left-right and up-down directions. The inner end of the main body portion 43 in the left-right direction is disposed between the first side wall portion 14 and the protrusion 28, which face each other in the front-rear direction. A portion of the main body portion 43 other than the end is disposed in the main storage portion 32. Each protrusion protrudes rearward from the outer end of the main body portion 43 in the left-right direction. The protrusions of each central frame portion 42 may be provided at multiple locations spaced apart from each other in the up-down direction, or may have a shape that extends continuously in the up-down direction.

[0039] At least one of the pair of protrusions is configured as an inclined protrusion 44. In the first embodiment, each of the pair of protrusions is configured as an inclined protrusion 44. Each inclined protrusion 44 is inclined with respect to the front-rear and left-right directions so that it is positioned further outward in the left-right direction toward the rear. Due to this inclination, the distance between the pair of inclined protrusions 44 becomes larger toward the rear. Each inclined protrusion 44 is inserted between the guide portion 17 and the bulge portion 15 so as to be movable up and down in a state where it is engaged with the guide portion 17 from the outside in the left-right direction.

[0040] As shown in Figures 1, 6, and 7, the middle connecting frame part 46 extends in the left-right direction between the first outer connecting frame part 19 and the second outer connecting frame part 33. The middle connecting frame part 46 connects only the upper ends of the pair of middle main frame parts 42 in the up-down direction. The middle frame 41 configured in this way has an inverted U-shape when viewed from the front-to-rear direction. The middle connecting frame part 46 is disposed within the connecting accommodation part 34. The middle connecting frame part 46 is movable in the up-down direction between the position indicated by the solid line in Figure 6 and the position indicated by the two-dot chain line.

[0041] <First Polarization Unit 51 and Second Polarization Unit 52> 2, 3, and 8, the first polarizing unit 51 and the second polarizing unit 52 are both made of films having a polarization axis. The second polarizing unit 52 is disposed in front of the first polarizing unit 51 so as to face the first polarizing unit 51. A front surface 56 of the second polarizing unit 52 forms part of the design surface of the light control device D.

[0042] Each of the first polarizing section 51 and the second polarizing section 52 includes a transparent film substrate 53 and two types of polarizing regions. The film substrate 53 is made of a transparent thermoplastic resin and has flexibility, such as PET (polyethylene terephthalate) resin, PE (polyethylene) resin, PP (polypropylene) resin, ABS (acrylonitrile-butadiene-styrene copolymer) resin, PVA (polyvinyl alcohol) resin, and TAC (triacetyl cellulose) resin.

[0043] Each polarizing region is bonded to one surface in the front-to-rear direction of the film substrate 53. In the first polarizing section 51, the polarizing region is bonded to the front surface of the film substrate 53. In the second polarizing section 52, the polarizing region is bonded to the rear surface of the film substrate 53.

[0044] Here, when it is necessary to distinguish between the two types of polarizing regions, one will be referred to as a first polarizing region A1 and the other as a second polarizing region A2. In Figures 2 and 3, to distinguish between the first polarizing region A1 and the second polarizing region A2 and make them easier to see, only the former is dotted. Each of the first polarizing section 51 and the second polarizing section 52 is provided with a plurality of first polarizing region A1 and a plurality of second polarizing region A2.

[0045] 4, each of the first polarizing region A1 and the second polarizing region A2 includes a film body 54 and a pair of transparent protective films 55 that sandwich the film body 54 from both sides in the front-to-rear direction. Like the film substrate 53, the first polarizing region A1 and the second polarizing region A2 are flexible.

[0046] The film body 54 is formed, for example, from PVA resin dyed with an iodine solution. The film body 54 is produced, for example, as follows: A PVA resin film is dyed with iodine. The PVA resin molecules that make up the film are bonded together with boric acid and stabilized. The film is stretched in one direction while still wet. The PVA resin molecules and iodine molecules align in the stretched direction. When this film is dried, the film body 54 is obtained, which has a polarization axis and polarization properties.

[0047] Each protective film 55 is intended to protect the film main body 54 from external impact, heat, humidity, etc. Each protective film 55 is made of an optically isotropic material, such as TAC resin. Each protective film 55 is attached to the film main body 54.

[0048] 2 and 3, each of the first polarizing regions A1 and each of the second polarizing regions A2 is a strip-shaped region whose horizontal dimension is longer than its vertical dimension. The vertical dimension of the first polarizing region A1 and the second polarizing region A2 is set to be the same. The first polarizing region A1 and the second polarizing region A2 are arranged alternately in the vertical direction.

[0049] In addition, when it is necessary to distinguish between the layer consisting of the polarizing area portions A1 and A2 in the first polarizing section 51 and the layer consisting of the polarizing area portions A1 and A2 in the second polarizing section 52, the former may be referred to as the first polarizing layer 51a and the latter as the second polarizing layer 52a.

[0050] As described above, the first polarizing section 51 and the second polarizing section 52 have a configuration in which the first polarizing region A1 and the second polarizing region A2 are bonded to the film substrate 53. This may cause undulations or unevenness in the first polarizing section 51 and the second polarizing section 52. Therefore, the distance between the first polarizing section 51 and the second polarizing section 52 refers to the average distance between the surface of the first polarizing section 51 facing the second polarizing section 52 (the front surface of the first polarizing layer 51a) and the surface of the second polarizing section 52 facing the first polarizing section 51 (the rear surface of the second polarizing layer 52a).

[0051] 5 shows an example of a polarization axis pattern (polarization axis pattern) in the polarization regions of the first polarizing layer 51a. As shown in FIG. 5, each first polarization region A1 has a first polarization axis PA1, and each second polarization region A2 has a second polarization axis PA2 that extends in a direction different from the first polarization axis PA1. In the first embodiment, the first polarization axis PA1 extends in a direction parallel to the length direction of the first polarization region A1 (the horizontal direction in FIG. 5). The second polarization axis PA2 extends in a direction (the vertical direction) perpendicular to the length direction of the second polarization region A2 (the horizontal direction in FIG. 5). The second polarization axis PA2 extends in a direction perpendicular to the first polarization axis PA1.

[0052] Although not shown, the polarization axis pattern in the polarizing region of the second polarizing layer 52a is similar to the polarization axis pattern in the first polarizing layer 51a. Note that layers for adding functions may be added to the first polarizing section 51 and the second polarizing section 52. For example, a low-friction layer may be formed on the polarizing regions A1, A2 of each of the first polarizing section 51 and the second polarizing section 52. The low-friction layer is provided for the purpose of increasing slipperiness, for example, increasing the sliding property of one of the first polarizing section 51 and the second polarizing section 52 relative to the other, increasing water repellency, etc. The low-friction layer is formed by subjecting the polarizing regions A1, A2 to a lubricant treatment, such as a water-repellent coating treatment or a silicone coating treatment.

[0053] 2 and 3, a hard coat layer may be formed on at least one of the rear surface of the first polarizing section 51 and the front surface of the second polarizing section 52. The hard coat layer provides the following useful effects: the effect of preventing scratches on the layer (film substrate 53) on which the hard coat layer is formed, among the layers constituting the first polarizing section 51 and the second polarizing section 52, the effect of making the layer less susceptible to dirt, the effect of improving light resistance and weather resistance by blocking ultraviolet rays, the effect of water repellency, etc.

[0054] 9 and 10 , both left-right end portions of the first polarization unit 51 are fixed to a pair of first outer main frame portions 12 in a state where they are pulled to both sides in the same direction. In the first embodiment, needles 62, which are called rivets, staples, or the like, are driven into the portions of both left-right end portions of the first polarization unit 51 that overlap the rear wall portion 13.

[0055] As shown in Figures 6 and 7, the upper end of the first polarization unit 51 is placed in the recess 21 of the connecting storage unit 34, and is fixed to the first outer connecting frame unit 19 by driving in a needle (not shown) similar to the needle 62.

[0056] 9 and 10 , both ends of the second polarization unit 52 in the left-right direction are fixed to the main body 43 of each central frame portion 42. In the first embodiment, both ends of the second polarization unit 52 in the left-right direction are placed on the rear surface of the main body 43 and, similar to the first polarization unit 51, are fixed to the main body 43 by driving needles 63 into them.

[0057] 6 and 7, the upper end of the second polarization unit 52, like the upper end of the first polarization unit 51, is disposed in the recess 21 of the connecting housing unit 34, and is fixed to the middle connecting frame unit 46 by driving in a needle (not shown) similar to the above-described needle 63. The upper end of the second polarization unit 52 may also be fixed to the middle connecting frame unit 46 by adhesive or the like.

[0058] <Elastic member 65> 1 and 7 , the elastic member 65 is used to apply an upward elastic biasing force to the middle frame 41. In the first embodiment, the elastic member 65 is a tension coil spring configured by winding a wire made of a material such as metal in a spiral shape around a central axis extending in the up-down direction, and pulling the middle frame 41 upward. The elastic member 65 is disposed in the spring accommodating chamber 22 in the center in the left-right direction of the first outer connecting frame part 19. The elastic member 65 is fixed at its upper end to the first outer connecting frame part 19 and at its lower end to the middle connecting frame part 46. In other words, the first outer connecting frame part 19 and the middle connecting frame part 46 are connected by the elastic member 65.

[0059] In addition, a part of the second outer frame 25, for example, one of the second outer main frame portions 26, is provided with an operating portion (not shown) that is operated when moving the middle frame 41 in the vertical direction through one of the middle main frame portions 42.

[0060] <Operation of the First Embodiment> First, the assembly of the light control device D will be described. When assembling the light control device D, as shown in Fig. 12 , the first polarization unit 51 is fixed to the first outer frame 11. For this fixation, a riveting tool 61 such as a stapler is used. One end of the first polarization unit 51 in the left-right direction is placed from the front against the rear wall portion 13 of one of the first outer main frame portions 12 of the first outer frame 11. A needle 62 is driven into the end of the first polarization unit 51 by the riveting tool 61, and the end is fixed to the rear wall portion 13 by the needle 62.

[0061] Next, the other end in the left-right direction of the first polarization unit 51 is pulled toward the side in the left-right direction that is away from the one end. The other end of the first polarization unit 51 is placed on the rear wall portion 13 of the other first outer main frame portion 12 of the first outer frame 11. A riveting tool 61 drives a needle 62 into the other end of the first polarization unit 51 that is under tension, and the end is fixed to the rear wall portion 13 by the needle 62.

[0062] The upper end of the first polarizing unit 51 is placed in the recess 21 in the first outer connecting frame unit 19, and is fixed to the first outer connecting frame unit 19 with needles (not shown) in the same manner as the above-mentioned two ends in the left-right direction (see Figure 6).

[0063] Furthermore, separately from the above-described fixing of the first polarizing unit 51 to the first outer frame 11, the second polarizing unit 52 is fixed to the middle frame 41 as shown in FIG. 13. During this fixing, each left-right end of the second polarizing unit 52 is placed on the rear surface of the main body 43 of the corresponding middle main frame unit 42. Furthermore, the upper end of the second polarizing unit 52 is placed on the rear surface of the middle connecting frame unit 46 (see FIG. 6). Needles 63 are driven into each left-right end and the upper end of the second polarizing unit 52 using a riveting tool 61. These driving operations are performed with the second polarizing unit 52 being lightly pulled in the left-right direction. The left and right ends of the second polarizing unit 52 are fixed to the middle main frame unit 42, and the upper end is fixed to the middle connecting frame unit 46.

[0064] 13, the second outer frame 25 is placed on the front side of the middle frame 41 to which the second polarization unit 52 is fixed. The middle frame 41 and the second outer frame 25 are brought closer to the first outer frame 11 from the front. As a result of this approach, each of the pair of inclined protrusions 44 of the middle frame 41 in the left-right direction is inserted between the corresponding guide portion 17 and bulge portion 15 of the first outer main frame portion 12. Furthermore, as a result of this approach, the locking claws 31 approach the locking holes 16 (see FIG. 9), and the second polarization unit 52 approaches the first polarization unit 51.

[0065] As the intermediate frame 41 approaches the first outer frame 11, each of the inclined protrusions 44 comes into contact with the corresponding guide portion 17. A load is then applied to the intermediate frame 41 that pushes the intermediate frame 41 toward the first outer frame 11, causing each of the inclined protrusions 44 to engage with the guide portion 17 while interfering with it, as shown in FIG. 10 . This engagement applies a tension to the second polarization section 52 that pulls it outward in the left-right direction. Furthermore, as shown in FIG. 9 , each of the locking claws 31 is inserted into the corresponding locking hole 16, thereby locking with the bulge portion 15. This locking connects the second outer frame 25 to the first outer frame 11, sandwiching the intermediate frame 41 from both sides in the front-to-rear direction.

[0066] When the first outer frame 11 and the second outer frame 25 are connected, the second polarizing unit 52 attempts to contract inward in the left-right direction against the tension. This force is transmitted to the pair of central main frame portions 42 of the intermediate frame 41. The pair of central main frame portions 42 are pulled inward in the left-right direction by the second polarizing unit 52. Therefore, as described above, a force acts on the intermediate frame 41 toward the front-rear direction and the left-right direction via the inclined protrusions 44. The distance between the second polarizing unit 52 and the first polarizing unit 51 is maintained at a small and appropriate value.

[0067] 1 and 7, an elastic member 65 is disposed in the spring accommodating chamber 22. The upper end of the elastic member 65 is attached to the lower part of the center of the first outer connecting frame part 19 in the left-right direction. The lower end of the elastic member 65 is attached to the center of the middle connecting frame part 46 in the same direction. The elastic member 65 connects the first outer connecting frame part 19 and the middle connecting frame part 46 at their centers in the left-right direction.

[0068] As shown in FIG. 10, when each of the inclined projections 44 engages with the guide portion 17 from the outside in the left-right direction, a frictional force is generated between the inclined projections 44 and the guide portion 17 .

[0069] As shown in FIG. 1 , in the first embodiment in which only the upper ends of the pair of central main frame parts 42 are connected by a single central connecting frame part 46, the frictional force is greatest at the upper ends, which are closest to the central connecting frame part 46 in the up-down direction. This frictional force decreases as the distance from the central connecting frame part 46 increases downward. This is because the lower ends of the pair of central main frame parts 42 are not connected by the central connecting frame part 46. Therefore, the load that pushes the middle frame 41 toward the first outer frame 11 is smaller than when the lower ends of the pair of central main frame parts 42 are connected by the central connecting frame part 46.

[0070] Next, the operation of the light control device D will be described. In the light control device D, the first polarization section 51 is fixed to the first outer frame 11 and therefore does not move. In contrast, the second polarization section 52 is fixed to the middle frame 41. The middle frame 41 is configured to be movable relative to the first outer frame 11 and the second outer frame 25. Therefore, when an operating load is applied to one of the middle main frame sections 42 to move it up or down by operating the operating section, the operating load is transmitted to the other middle main frame section 42 via the middle connecting frame section 46. The middle frame 41 moves in the same direction as the operating load applied to the middle main frame section 42 (see FIG. 6).

[0071] As shown in Figure 10, the frictional force generated between each inclined protrusion 44 and the guide portion 17 decreases as it moves downward away from the middle connecting frame portion 46, so the operating load required to move the middle frame 41 in the vertical direction is lighter than if the frictional force did not decrease.

[0072] Meanwhile, tension is applied to the second polarization section 52. The second polarization section 52 tries to shrink inward in the left-right direction against the tension. The pair of central main frame sections 42 are pulled inward in the left-right direction by the second polarization section 52. As a result, the frictional force generated between each inclined protrusion 44 and the guide section 17 becomes even greater.

[0073] Here, a downward force acts on intermediate frame 41 and second polarization section 52 fixed thereto due to their weight (their own weight). Therefore, in order to move the middle frame 41 and the second polarization unit 52 upward, it is necessary to apply an operating load that is directed upward and is large enough to overcome the frictional force and the downward force.

[0074] In this regard, in the first embodiment, an elastic biasing force of the elastic member 65 acts on the central main frame portion 42 of the middle frame 41, biasing it upward. By applying a small upward operating load in proportion to this elastic biasing force, it is possible to move the middle frame 41 and the second polarization unit 52 upward. In other words, the operating load applied when moving the middle frame 41 and the second polarization unit 52 upward becomes lighter.

[0075] 1 and 7, the elastic biasing force with which the elastic member 65 biases the middle frame 41 upward is transmitted to the middle connecting frame portion 46 to which the elastic member 65 is connected. This elastic biasing force is transmitted to the pair of middle main frame portions 42 via the middle connecting frame portion 46. Therefore, when an operating load in the vertical direction is applied to one of the middle main frame portions 42 of the middle frame 41, both middle main frame portions 42 move in the vertical direction while applying an appropriate tension to the second polarization portion 52.

[0076] Furthermore, an elastic member 65 is disposed in the spring accommodating chamber 22 of the first outer connecting frame portion 19, at the center in the left-right direction of the first outer connecting frame portion 19. Therefore, the elastic biasing force of the elastic member 65 acts on the central connecting frame portion 46 in a balanced state in the left-right direction. The elastic biasing force acts evenly on the pair of central main frame portions 42. The pair of central main frame portions 42 move smoothly in the up-down direction while being prevented from tilting.

[0077] Next, the dimming by the dimming device D will be described. 1 and 3, when light is incident on the dimming device D from the front, the light becomes linearly polarized in a direction along the first polarization axis PA1 when passing through the second polarizing section 52. Furthermore, the light incident on the second polarizing section 52 becomes linearly polarized in a direction along the second polarization axis PA2 when passing through the second polarizing region A2.

[0078] The degree of light transmission in the second polarizing unit 52 and the first polarizing unit 51 is determined by which of the polarizing region sections A1 and A2 in the first polarizing unit 51 faces (overlaps) in the front-to-back direction with respect to the polarizing region sections A1 and A2 in the second polarizing unit 52. The combination of the first polarization axis PA1 and the second polarization axis PA2 facing in the front-to-back direction is changed by moving the second polarizing unit 52 in the vertical direction, as shown in Fig. 6. In other words, the above combination is changed by moving the second polarizing unit 52 in the vertical direction relative to the first polarizing unit 51.

[0079] As shown in FIGS. 2 and 3 , when the first polarization region A1 in the second polarizing unit 52 and the first polarization region A1 in the first polarizing unit 51 are opposed to each other in the front-to-back direction due to the above-described movement, light control is performed as follows. The direction in which the first polarization axis PA1 in the first polarization region A1 extends is parallel to the direction in which the first polarization axis PA1 in the latter first polarization region A1 extends. In this case, the second polarization region A2 in the second polarizing unit 52 and the second polarization region A2 in the first polarizing unit 51 are opposed to each other in the front-to-back direction. The direction in which the second polarization axis PA2 in the second polarization region A2 extends is parallel to the direction in which the second polarization axis PA2 in the former second polarization region A2 extends. Therefore, all of the light incident on the second polarizing unit 52 and transmitted through the second polarizing unit 52 is transmitted through the first polarizing unit 51.

[0080] In contrast, when the above movement causes the first polarization region A1 of the second polarizing section 52 and the second polarization region A2 of the first polarizing section 51 to face each other in the front-to-back direction, light control is performed as follows. The extension direction of the first polarization axis PA1 of the first polarization region A1 is perpendicular to the extension direction of the second polarization axis PA2 of the second polarization region A2. In this case, the second polarization region A2 of the second polarizing section 52 and the first polarization region A1 of the first polarizing section 51 face each other in the front-to-back direction. The extension direction of the second polarization axis PA2 of the second polarization region A2 is perpendicular to the extension direction of the first polarization axis PA1 of the first polarization region A1. Therefore, all light that enters the second polarizing section 52 and then transmits through the second polarizing section 52 is blocked (shielded) by the first polarizing section 51.

[0081] In this way, the second polarizing unit 52 moves relative to the first polarizing unit 51 in the vertical direction in response to operation of the operating unit, thereby adjusting the degree of light transmission in the second polarizing unit 52 and the first polarizing unit 51.

[0082] Next, the relationship between the width of the stripes as seen from diagonally in front of the light control device D and the distance between the first polarizing layer 51a and the second polarizing layer 52a will be described. 11A and 11B show a portion of the first polarizing layer 51a and a portion of the second polarizing layer 52a extracted from the light control device D. These figures also show a state in which the first polarizing region A1 in the second polarizing layer 52a and the first polarizing region A1 in the first polarizing layer 51a face each other in the front-to-back direction, i.e., are at the same height. In this state, the second polarizing region A2 in the second polarizing layer 52a and the second polarizing region A2 in the first polarizing layer 51a face each other in the front-to-back direction. When a user U views the second polarizing layer 52a from the front, the second polarizing layer 52a and the first polarizing layer 51a are visible through the second polarizing layer 52a and the first polarizing layer 51a. This is because light that has passed through the second polarizing layer 52a passes through the first polarizing layer 51a.

[0083] 11(A) and 11(B), when a user U views the second polarizing layer 52a in a direction inclined relative to the front-to-back direction, for example, from diagonally above the front, a black stripe (line) extending in the left-to-right direction is visible at the boundary between the first polarizing region A1 and the second polarizing region A2. As shown in FIG. 11(A), when the distance between the second polarizing layer 52a and the first polarizing layer 51a in the front-to-back direction is narrow, the width W of the stripe is narrow and the stripe is not noticeable. However, as shown in FIG. 11(B), as the distance increases, the width W increases. As the width W increases, the stripe becomes more noticeable, and the display quality of the light control device D decreases.

[0084] In this regard, in the first embodiment, as described above, the first polarizing section 51 and the second polarizing section 52 are narrowly spaced apart in the front-to-rear direction, thereby narrowing the gap between the first polarizing layer 51a and the second polarizing layer 52a. The narrow gap between the first polarizing layer 51a and the second polarizing layer 52a is, for example, 1 mm or less, and more preferably 0.5 mm or less. Therefore, the width W of the streaks is narrowed as shown in FIG. 11(A), making the streaks less noticeable.

[0085] Next, the effect of the light control device D on the display quality will be described. The first polarizing section 51 and the second polarizing section 52 are formed of a film. Therefore, the first polarizing section 51 and the second polarizing section 52 are prone to wrinkles due to environmental changes, such as shrinkage due to drying and expansion due to water absorption. If the first polarizing section 51 and the second polarizing section 52 wrinkle, the display quality of the light control device D deteriorates.

[0086] This can be addressed by continuously applying tension to each of the first polarization section 51 and the second polarization section 52. In this regard, it is relatively easy to continuously apply tension to the first polarization section 51 because it does not move. However, it is difficult to continuously apply tension to the second polarization section 52 because it moves.

[0087] In this regard, in the first embodiment, as shown in FIG. 10, the protrusions of each central main frame portion 42 engage with the corresponding guide portions 17 of the first outer main frame portion 12 from the outside in the left-right direction. The second polarization unit 52 fixed to the pair of central frame portions 42 moves together with the central frame 41 in the vertical direction relative to the first outer frame 11 and the second outer frame 25. During this movement, each protrusion is guided in its vertical movement by the corresponding guide portion 17.

[0088] Here, in the first embodiment, each of the pair of protrusions is configured as an inclined protrusion 44. The inclined protrusion 44 is inclined with respect to the front-rear and left-right directions so that the more rearward it is positioned outward in the left-right direction. This inclined protrusion 44 engages with the guide portion 17 from the outside in the left-right direction, and a tension is applied to the second polarization portion 52 that pulls it outward in the left-right direction. Therefore, regardless of the position of the middle frame 41 in the up-down direction, it is possible to continuously apply tension to the second polarization portion 52 outward in the left-right direction. By maintaining this tension, the second polarization portion 52 is less likely to sag over a long period of time.

[0089] Furthermore, although the distance between the first polarizing section 51 and the second polarizing section 52 in the front-to-rear direction is narrow, the phenomenon of the loose second polarizing section 52 rubbing against the first polarizing section 51 as it moves is unlikely to occur, and wear caused by rubbing is suppressed.

[0090] <Effects of the first embodiment> (1-1) As shown in Figure 10, each central main frame portion 42 has a protrusion that protrudes rearward. Each first outer main frame portion 12 has a guide portion 17 that protrudes forward. Each guide portion 17 engages with the protrusion from the inside in the left-right direction, thereby guiding the up-and-down movement of the protrusion. Each protrusion is configured with an inclined protrusion 44 that is inclined in the front-to-rear and left-to-right directions so that the more rearward it is positioned outward in the left-to-right direction.

[0091] Therefore, tension can be continuously applied in the left-right direction to the moving second polarization section 52. Deterioration of the appearance of the light control device D due to sagging of the second polarization section 52 can be suppressed. Furthermore, although the distance between the first polarizing section 51 and the second polarizing section 52 in the front-to-rear direction is narrow, it is possible to make it difficult for the second polarizing section 52 to rub against the first polarizing section 51. This makes it possible to suppress wear caused by rubbing, and to suppress deterioration in the appearance of the light control device D due to wear.

[0092] Furthermore, the force of the second polarizing unit 52 shrinking inward in the left-right direction against the tension acts on the middle frame 41 to apply a force toward the front, making it possible to maintain a small and appropriate distance between the second polarizing unit 52 and the first polarizing unit 51. This makes it even less likely that the second polarizing unit 52 will rub against the first polarizing unit 51 and become worn. This further reduces deterioration in the appearance of the light control device D due to wear.

[0093] (1-2) As shown in FIG. 1, the middle frame 41 includes a single middle connecting frame portion 46 that extends in the left-right direction and connects only the upper ends of the pair of middle main frame portions 42 together. Therefore, when manufacturing the light control device D, the load applied to the middle frame 41 when pushing the middle frame 41 into the first outer frame 11 can be reduced, improving workability. Furthermore, when using the light control device D, the operating load required to move the middle frame 41 in the up and down direction is reduced, making it easier to operate.

[0094] (1-3) As shown in Fig. 1 and Fig. 7, the light control device D further includes an elastic member 65 that biases the middle frame 41 upward. This reduces the operating load required to move the middle frame 41 and the second polarization unit 52 upward, making the operation easier.

[0095] (1-4) The elastic member 65 connects the middle connecting frame portion 46 of the middle frame 41 and the first outer connecting frame portion 19 of the first outer frame 11. Therefore, when an operating load in the vertical direction is applied to one of the middle main frame portions 42 of the middle frame 41, both middle main frame portions 42 can be moved in the vertical direction while applying an appropriate tension to the second polarization portion 52.

[0096] (1-5) The elastic member 65 connects the left-right center of the first outer connecting frame portion 19 and the left-right center of the middle connecting frame portion 46. Therefore, the pair of middle main frame portions 42 can smoothly move the middle frame 41 in the up-down direction while preventing tilting.

[0097] (Second embodiment) Next, a second embodiment of the light control device will be described with reference to FIG. In the second embodiment, the middle frame 41 has a pair of middle connecting frame portions 46. The pair of middle connecting frame portions 46 extend in the left-right direction while being spaced apart from each other in the up-down direction. The upper middle connecting frame portion 46 connects the upper ends of the pair of middle main frame portions 42. The lower middle connecting frame portion 46 connects the lower ends of the pair of middle main frame portions 42. In other words, each middle connecting frame portion 46 connects the ends of the pair of middle main frame portions 42 on the same side in the up-down direction. With this configuration, the middle frame 41 has a rectangular ring shape.

[0098] The same is true for the first outer frame 11 and the second outer frame 25. That is, the first outer frame 11 has a pair of first outer connecting frame portions 19. The pair of first outer connecting frame portions 19 extend in the left-right direction while being spaced apart from each other in the up-down direction. The upper first outer connecting frame portion 19 connects the upper ends of the pair of first outer main frame portions 12. The lower first outer connecting frame portion 19 connects the lower ends of the pair of first outer main frame portions 12. With this configuration, the first outer frame 11 has a rectangular ring shape.

[0099] The second outer frame 25 also has a pair of second outer connecting frame portions 33. The pair of second outer connecting frame portions 33 extend in the left-right direction while being spaced apart from each other in the up-down direction. The upper second outer connecting frame portion 33 connects the upper ends of the pair of second outer main frame portions 26. The lower second outer connecting frame portion 33 connects the lower ends of the pair of second outer main frame portions 26. With this configuration, the second outer frame 25 has a rectangular ring shape.

[0100] In the second embodiment as well, an elastic member 65 connects the upper central connecting frame portion 46 and the upper first outer connecting frame portion 19 together. The configuration other than the above is the same as that of the first embodiment. Therefore, in the second embodiment, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0101] <Operation of the Second Embodiment> The light control device D of the second embodiment basically functions in the same way as the light control device D of the first embodiment.

[0102] When an operating load is applied to one of the central frame parts 42 to move it in the up-down direction through operation of the operating part, the operating load is transmitted to the other central frame part 42 via both central connecting frame parts 46. Moreover, the distance between the pair of central frame parts 42 in the left-right direction is regulated by the pair of central connecting frame parts 46. This distance is uniform or approximately uniform at any point in the up-down direction.

[0103] Therefore, the other central frame part 42 is moved in the vertical direction to the same extent as the one central frame part 42 to which the operating load is applied. As a result, the second polarization part 52 is maintained in a tensed state in the horizontal direction, regardless of its position in the vertical direction.

[0104] <Effects of the second embodiment> Therefore, according to the second embodiment, the same advantages as those (1-1) and (1-3) to (1-5) in the first embodiment can be obtained. In addition, the second embodiment can obtain the following advantage (2-1) corresponding to the above advantage (1-2).

[0105] (2-1) In the second embodiment, the middle frame 41 includes a pair of middle connecting frame portions 46, and each of the middle connecting frame portions 46 connects the ends of a pair of middle main frame portions 42 on the same vertical side. With this configuration, the middle frame 41 has a rectangular ring shape. Therefore, it is easy to maintain the second polarization unit 52 in a taut state in the left-right direction, regardless of its position in the up-down direction.

[0106] <Example of change> The first and second embodiments can be modified as follows: Each embodiment and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0107] (Frame-related matters) In the first embodiment in which the middle frame 41 includes a single middle connecting frame part 46, instead of connecting the upper ends of a pair of middle main frame parts 42 together by the middle connecting frame part 46, the lower ends may be connected together. In this case, in the first outer frame 11, the lower ends of the pair of first outer main frame parts 12 are connected together by the first outer connecting frame part 19. In the second outer frame 25, the lower ends of the pair of second outer main frame parts 26 are connected together by the second outer connecting frame part 33.

[0108] The middle frame 41 may have a middle main frame portion 42 and a middle connecting frame portion 46 that extend in directions different from those in the first and second embodiments. For example, the middle frame 41 may have a middle main frame portion 42 that extends in the left-right direction and a middle connecting frame portion 46 that extends in the up-down direction, which is the opposite of those in the first and second embodiments. In this case, the directions in which the first outer main frame portion 12 and the first outer connecting frame portion 19 in the first outer frame 11 extend are changed in the same manner as above. The directions in which the second outer main frame portion 26 and the second outer connecting frame portion 33 in the second outer frame 25 extend are also changed in the same manner as above.

[0109] In this modification, the up-down direction is the first direction, and the left-right direction is the second direction. The middle frame 41 and the second polarizing unit 52 are moved in the left-right direction. The second polarizing unit 52 is moved in the left-right direction relative to the first polarizing unit 51.

[0110] Furthermore, the middle frame 41 may have a middle main frame portion 42 and a middle connecting frame portion 46 that extend in directions that are inclined relative to the up-down direction and the left-right direction. In this case, the directions in which the first outer main frame portion 12 and the first outer connecting frame portion 19 extend in the first outer frame 11, and the directions in which the second outer main frame portion 26 and the second outer connecting frame portion 33 extend in the second outer frame 25, are changed in the same manner as above.

[0111] 10, the second outer frame 25 may be disposed rearward relative to the first outer frame 11, opposite to the first and second embodiments. In this modification, the pair of inclined protrusions 44 of the middle frame 41 each protrude forward from the main body 43. The pair of guide portions 17 each protrude rearward from the rear wall 13. The second polarizing portion 52 is disposed rearward of the first polarizing portion 51.

[0112] Only one of the pair of protrusions may be configured as the inclined protrusion 44. Even in this case, by engaging the inclined protrusion 44 with the guide portion 17 from the outside in the left-right direction, it is possible to apply tension to the second polarization portion 52 outward in the left-right direction.

[0113] (Matters regarding polarizing parts) At least one end of the first polarizing unit 51 in the left-right direction may be fixed to the rear wall 13 of the first outer main frame 12 by a method different from that of the first and second embodiments. FIG. 15 shows a modified example in which the end of the first polarizing unit 51 is fixed to the rear wall 13 by welding. In this case, a hole 57 is formed in the end of the first polarizing unit 51. A pin-shaped boss 20 is formed in the rear wall 13, as indicated by the two-dot chain line in FIG. 15 . The boss 20 is inserted into the hole 57. A welded horn (not shown) is pressed against the portion of the boss 20 protruding from the hole 57, and the welded horn is ultrasonically vibrated. Frictional heat is generated at the interface between the welded horn and the boss 20, melting the boss 20 and fixing the end of the first polarizing unit 51 to the rear wall 13.

[0114] The upper end of the first polarizing section 51 may also be fixed to the first outer connecting frame section 19 by welding. Furthermore, the fixing of the left and right ends of the second polarizing section 52 to the central main frame section 42 and the fixing of the upper end of the second polarizing section 52 to the central connecting frame section 46 may also be performed by welding.

[0115] Each of the first polarizing layer 51a and the second polarizing layer 52a may include three or more types of polarizing regions. The second polarization axis PA2 in each second polarizing region A2 may be arranged in a different manner (polarization axis pattern) from that in the first and second embodiments, provided that the second polarization axis PA2 extends in a direction perpendicular to the first polarization axis PA1 in each first polarizing region A1. Examples of such arrangements are shown in Figures 16 and 17.

[0116] 16, the first polarization axis PA1 is tilted at 45° with respect to the left-right direction. The second polarization axis PA2 is tilted at 45° with respect to the left-right direction in the opposite direction to the first polarization axis PA1. The second polarization axis PA2 extends in a direction perpendicular to the first polarization axis PA1.

[0117] In the modification shown in Fig. 17, the first polarizing region A1 and the second polarizing region A2 are each divided into a plurality of small sections in their length direction (the left-right direction in Fig. 17). The first polarization axis PA1 and the second polarization axis PA2 are arranged so that the directions of the polarization axes of adjacent small sections are perpendicular to each other. In this case, the first polarization axis PA1 and the second polarization axis PA2 are arranged so that the small section of the first polarizing region A1 and the adjacent small section of the second polarizing region A2 extend in different directions from each other.

[0118] The second polarization axis PA2 may extend in a direction that intersects (is tilted) obliquely with the first polarization axis PA1, instead of in a direction that is perpendicular to the first polarization axis PA1. In the first polarizing section 51 shown in Fig. 2, the polarizing regions A1 and A2 may be formed on the rear surface of the film substrate 53, opposite to the first and second embodiments. In the second polarizing section 52 shown in Fig. 3, the polarizing regions A1 and A2 may be formed on the front surface of the film substrate 53, opposite to the above embodiments.

[0119] In both the first polarizing section 51 and the second polarizing section 52, the polarizing regions A1 and A2 may be formed on the front surface of the film substrate 53 or on the rear surface thereof. In any of the above modified examples, the distance between the first polarization section 51 and the second polarization section 52, i.e., the average distance between the surface (front surface) of the first polarization section 51 facing the second polarization section 52 and the surface (rear surface) of the second polarization section 52 facing the first polarization section 51, is set to a small value (1 mm or less).

[0120] (Matters regarding elastic member 65) In FIG. 7, the elastic member 65 may connect the second outer connecting frame portion 33 and the middle connecting frame portion 46 together.

[0121] In the first and second embodiments, the elastic members 65 may be disposed at locations other than the center in the left-right direction. For example, a pair of elastic members 65 may be disposed on both sides in the left-right direction. Each elastic member 65 may bias the middle frame 41 upward in both middle main frame portions 42.

[0122] As the elastic member 65 that biases the middle frame 41 upward, instead of a tension coil spring that pulls the middle frame 41 upward, a compression spring (compression spring) such as a compression coil spring that presses the middle frame 41 upward may be used.

[0123] Instead of a spring, the elastic member 65 may be an elastic body made of an elastic material such as rubber. In at least one of the first and second embodiments, the elastic member 65 may be omitted as appropriate. [Explanation of symbols]

[0124] 11...First outer frame 12...First outer main frame part 17...Guide section 25...Second outer frame 26...Second outer main frame part 41...Medium frame 42...Center main frame section 44…Slanted protrusion 46...Middle connecting frame section 51...First polarizing unit 52...Second polarizing unit 65...Elastic member D…Dimmer device PA1...First polarization axis (polarization axis) PA2: Second polarization axis (polarization axis) U…User

Claims

1. a first outer frame having a pair of first outer main frame portions extending in a second direction perpendicular to the front-rear direction and the first direction, the first outer frame portions being spaced apart from each other in a first direction perpendicular to the front-rear direction; a second outer frame having a pair of second outer main frame portions extending in the second direction while being spaced apart from each other in the first direction, and disposed in the front-rear direction of the first outer frame; an intermediate frame having a pair of intermediate main frame portions extending in the second direction between the first outer main frame portion and the second outer main frame portion while being spaced apart from each other in the first direction; a first polarizing section and a second polarizing section, each of which is made of a film having a polarization axis and which face each other in the front-rear direction; both end portions in the first direction of the first polarization unit are fixed to a pair of the first outer main frame portions, and both end portions in the first direction of the second polarization unit are fixed to a pair of the central main frame portions, a light control device that adjusts a degree of light transmission in the first polarization unit and the second polarization unit by moving the middle frame in the second direction relative to the first outer frame, Each central frame portion has a protrusion that protrudes toward the first outer frame portion in the front-rear direction, each first outer main frame portion has a guide portion that protrudes toward the central main frame portion in the front-rear direction, engages with the protrusion from the inside in the first direction, and guides movement of the protrusion in the second direction; A dimming device, wherein at least one of the protrusions is configured as an inclined protrusion that is inclined with respect to the front-to-rear direction and the first direction so that it is positioned more outward in the first direction toward the first outer main frame portion in the front-to-rear direction.

2. the intermediate frame includes a pair of intermediate connecting frame portions extending in the first direction while being spaced apart from each other in the second direction, The light control device according to claim 1 , wherein each of the central connecting frame portions connects end portions of the pair of central main frame portions on the same side in the second direction.

3. The light control device according to claim 1 , wherein the middle frame includes a single middle connecting frame portion that extends in the first direction and connects only one end of the pair of middle main frame portions in the second direction.

4. the second direction is an up-down direction, The light control device according to any one of claims 1 to 3, further comprising an elastic member that elastically biases the middle frame upward.

5. The middle frame includes a middle connecting frame portion that extends in the first direction and connects at least one end of each of the pair of middle main frame portions in the up-down direction, The light control device according to claim 4 , wherein the elastic member connects the middle connecting frame portion to the first outer frame or the second outer frame.

Images