Lighting device

Abstract

The present invention provides a lighting device equipped with a rod-shaped light guide having a bent portion, which provides a lighting device with high brightness uniformity. [Solution] The present invention provides a lighting device 1 comprising a rod-shaped light guide 10 having a bent portion 103 and non-bent portions 101 and 102, a light source 14 that supplies light to the inside of the light guide 10, a housing 11 that houses the light guide 10 inside a linear recess 117, a cover 13 having a linear opening 130 for allowing light emitted from the light guide 10 to pass through, and a lens 12 installed between the light guide 10 and the opening 130 of the cover 13, wherein when viewed from the overlapping direction of the light guide 10 and the cover 13, the position of the bent portion 103 does not overlap with the position of the opening 130, or the overlap width between the position of the bent portion 103 and the position of the opening 130 is smaller than the overlap width between the positions of the non-bent portions 101 and 102 and the position of the opening 130, thereby increasing the amount of light emitted from the bent portion 103 taken out from the opening 130.

Description

Technical Field

[0001] The present invention relates to a lighting device. Background Art

[0002] Conventionally, there has been known a lighting device attached to a cup holder used as an interior component for automobiles or the like, the lighting device including an annular light guide disposed so as to surround a cup accommodating portion (see Patent Document 1).

[0003] According to the lighting device described in Patent Document 1, supplying light from a light source to the light guide to cause light emission improves the design of the cup holder and also makes it easy to place a beverage container into the cup accommodating portion even at night. Prior Art Literature Patent Literature

[0004] Patent Document 1 International Publication No. 2015 / 041104 Summary of the Invention Problem to be Solved by the Invention

[0005] In the lighting device described in Patent Document 1, the light guide is accommodated in a recessed portion of the cup holder provided around the cup accommodating portion, and light propagating inside the light guide is emitted from a portion of the light guide that is not covered by the inner surface of the recessed portion.

[0006] However, in a bent portion of the light guide, light propagating through the inside is less likely to travel along the length direction of the light guide and more likely to leak to the outside than in an unbent portion. Therefore, there is a locally intense light-emitting region around the bent portion of the light guide, which impairs the uniformity of brightness of the lighting device. Although the lighting device described in Patent Document 1 uses a diffusion cover for diffusing light emitted from the light guide, it is difficult to eliminate the aforementioned non-uniformity of brightness.

[0007] The object of the present invention is to provide a lighting device equipped with a rod-shaped light guide having a bent portion, which provides a highly uniform brightness. [Means for solving the problem]

[0008] One aspect of the present invention provides the following lighting device to achieve the above objective.

[0009] [1] A lighting device comprising: a rod-shaped light guide having a bent portion and a non-bent portion; a light source that supplies light to the interior of the light guide; a housing that houses the light guide inside a linear recess; a cover having a linear opening for allowing light emitted from the light guide to pass through; and a lens installed between the light guide and the opening of the cover, wherein, when viewed from the overlapping direction of the light guide and the cover, the position of the bent portion does not overlap with the position of the opening, or the overlap width between the position of the bent portion and the position of the opening is smaller than the overlap width between the position of the non-bent portion and the position of the opening, thereby increasing the amount of light emitted from the bent portion taken out of the opening. [2] The lighting device according to [1] above, wherein the structure is such that when viewed from the overlapping direction of the light guide and the cover, there exists a gap between the bent portion and the housing in which at least a portion of the position overlaps with the position of the opening. [3] The lighting device according to [1] above, wherein the structure is such that a flat surface is formed on the side surface of the light guide extending along the length direction of the light guide, and in a cross section perpendicular to the length direction of the light guide, the flat surface at the bent portion is inclined from a surface parallel to the cover toward the opening. [4] The lighting device according to [1] above, wherein the structure is a linear projection formed in the portion of the lens that covers the bent portion and fits inside the opening. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a lighting device equipped with a rod-shaped light guide having a bent portion, which provides a lighting device with high brightness uniformity. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a perspective view showing the external appearance of a lighting device according to a first embodiment of the present invention. [Figure 2] Figure 2 is an exploded perspective view showing the configuration of the lighting device (excluding the light source and light guide). [Figure 3] Figure 3 is a top view of the lighting device 1 (excluding the light source and light guide). [Figure 4] Figures 4(a) to 4(c) show the structure of a lighting device as a comparative example. [Figure 5] Figures 5(a) to 5(c) show the structure of a lighting device as another comparative example. [Figure 6] Figures 6(a) to 6(c) show the structure of a lighting device according to the first embodiment of the present invention. [Figure 7] Figures 7(a) to 7(c) show the structure of a lighting device according to a second embodiment of the present invention. [Figure 8] Figures 8(a) to 8(c) show the structure of a lighting device according to a third embodiment of the present invention. [Modes for carrying out the invention]

[0012] [First Embodiment] Figure 1 is a perspective view showing the external appearance of a lighting device 1 according to a first embodiment of the present invention. Figure 2 is an exploded perspective view showing the configuration of the lighting device 1 (excluding the light source 14 and the light guide 15). Figure 3 is a top view of the lighting device 1 (excluding the light source 14 and the light guide 15).

[0013] The lighting device 1 is a lighting device suitably used for vehicle interiors and the like, and comprises: a rod-shaped light guide 10 having non-bent portions 101, 102 and a bent portion 103; a light source 14 that supplies light into the interior of the light guide 10; a housing 11 that accommodates the light guide 10 inside a linear recess 117; a cover 13 having a linear opening 130 for allowing light emitted from the light guide 10 to pass through; and a lens 12 disposed between the light guide 10 and the opening of the cover.

[0014] The light guide 10 is made of a material that transmits visible light emitted from the light source 14, for example, a material such as acrylic resin or polycarbonate (PC) resin.

[0015] The non-bent portions 101 and 102 of the light guide 10 are portions that are not bent or substantially not bent, and are linear or substantially linear. The bent portion 103 of the light guide 10 is a bent curved portion (for example, bent at an angle of about 80 to 100° with R25 or less (a curvature radius of 25 mm or less)).

[0016] In the example shown in Figures 1 and 2, the entire light guide 10 is disposed substantially within the same plane, and both the non-bent portions 101, 102 and the bent portion 103 are disposed substantially parallel to the flat plate-shaped cover 13.

[0017] As shown in Figure 1, for example, the light guide 10 is supplied with light emitted from the light source 14 from an end 104 in the length direction thereof. The light supplied from both ends 104 travels through the non-bent portion 101, the bent portion 103, and the non-bent portion 102 in this order while being partially emitted from the side surface of the light guide 10 respectively, and merges in the middle of the non-bent portion 102.

[0018] A typical shape of a radial cross-section of the light guide 10 is circular. As shown in FIG. 6 and other figures described later, the light guide 10 may have a flat surface 105 extending along the length direction of the light guide 10 on a side surface thereof. In this case, the flat surface 105 reflects light propagating inside the light guide 10, so that light is easily emitted from the opposite side of the flat surface 105. Typically, optical processing such as lens cutting or optical diffusion treatment for efficiently reflecting light to the opposite side of the flat surface 105 is performed on the flat surface 105.

[0019] The housing 11 is a component that accommodates the light guide 10 inside the linear recess 117. As shown in FIG. 6 and other figures described later, the recess 117 of the housing 11 is an inner space formed by a bottom portion 114 covering the lower side of the light guide 10 and a side wall portion 115 covering the lateral sides of the light guide 10. It should be noted that terms representing directions such as upper, lower, and lateral used in the present embodiment represent directions in a state where the cover 13 is located on the upper side of the light guide 10 as shown in FIG. 6(b), (c) and other figures. For example, "upper" refers to a direction facing the upper side in FIG. 6(b) and (c), "lower" refers to a direction facing the lower side in FIG. 6(b) and (c), and "lateral" refers to directions facing the left and right sides in FIG. 6(b) and (c).

[0020] The housing 11 has a shape corresponding to the shape of the light guide 10 for accommodating the light guide 10. For example, the housing 11 has a portion 111, a portion 113, and a portion 112 that respectively accommodate the non-bent portion 101, the bent portion 103, and the non-bent portion 102 of the light guide 10. In the example shown in FIGS. 1 and 2, the housing 11, together with the light guide 10, is arranged substantially parallel to the flat plate-shaped cover 13.

[0021] The housing 11 is made of a material that does not transmit visible light emitted from the light source 14. Since the inner surface of the housing 11 can reflect light emitted from the light guide 10, the housing 11 can guide the direction of light emitted from the light guide 10 toward the opening of the housing 11, that is, toward the lens 12.

[0022] The lens 12 is made of a material that transmits visible light emitted from the light source 14, such as an acrylic resin or polycarbonate (PC) resin. By extracting the light emitted from the light guide 10 through the lens 12, the brightness distribution in the in-plane direction of the lens 12 can be made smoother.

[0023] The lens 12 is a strip-shaped lens that covers the linear opening of the recess 117 in the housing 11 that houses the light guide 10 (i.e., covers the top of the light guide 10), and has a shape corresponding to the shape of the light guide 10. For example, the lens 12 has portions 121, 123, and 122 that cover the top of the non-bent portion 101, bent portion 103, and non-bent portion 102 of the light guide 10, respectively. In the example shown in Figure 2, the lens 12 is positioned together with the light guide 10 and the housing 11, substantially parallel to the flat cover 13.

[0024] The cover 13 is a component that is visible from the outside when the lighting device 1 is installed in the interior of a vehicle, and may also function as a design component. The surface of the cover 13 may be decorated.

[0025] The cover 13 is made of a material that does not transmit visible light emitted from the light source 14. The cover 13 is flat, as shown in Figures 1-3, for example, and the opening 130 of the cover 13 has a planar pattern (a U-shaped pattern in the example shown in Figures 1-3).

[0026] In the lighting device 1, the light emitted from the light guide 10 enters the inside of the lens 12 and is then emitted outside the lighting device 1 through the opening 130 of the cover 13. In other words, the linear opening 130 of the cover 13 becomes the light-emitting area of ​​the lighting device 1.

[0027] The opening 130 of the cover 13 is located above the lens 12 and is an opening for extracting light emitted from the light guide 10 through the lens 12, and has a shape corresponding to the shape of the light guide 10. For example, the opening 130 has portions 131, 133, and 132 located near the non-bent portion 101, bent portion 103, and non-bent portion 102 of the light guide 10, respectively.

[0028] The light source 14 is a light-emitting device that emits visible light, equipped with an LED or other light-emitting element. The light source 14 supplies light to the light guide 10 via a rod-shaped light guide 15, as shown in Figure 1, for example. In this way, the light from the light source 14 may be supplied to the light guide 10 via another light guide.

[0029] Figures 4(a) to 4(c) show the structure of lighting device 5 as a comparative example. Lighting device 5 is the device that formed the basis for the invention of lighting device 1 according to the first embodiment of the present invention, and is composed of the same parts as lighting device 1, but differs from lighting device 1 in terms of the partial shape of the parts, as described below.

[0030] Figure 4(a) is a top view of the light guide 10 and housing 11 of the lighting device 5, with the position of the edge of the opening 130 of the cover 13 indicated by a dotted line. Figure 4(b) is a cross-sectional view of the non-bent portion 101 and its surroundings, cut at the position of the cutting line A1-A1 shown in Figure 4(a). The cross-section of the non-bent portion 102 and its surroundings is the same as that shown in Figure 4(b). Figure 4(c) is a cross-sectional view of the bent portion 103 and its surroundings, cut at the position of the cutting line A2-A2 shown in Figure 4(a).

[0031] In the structure of the lighting device 5 shown in Figures 4(a) to (c), the shape of the opening 130 of the light guide 10, housing 11, lens 12, and cover 13, and their relative positions are almost the same in the non-bent sections 101 and 102 and the bent section 103.

[0032] In this structure, light propagating from the non-bendable portion 101 to the bendable portion 103 leaks significantly at the bendable portion 103, resulting in stronger light emitted from the bendable portion 103 and weaker light emitted from the portion of the non-bendable portion 102 closest to the bendable portion 103. Consequently, the brightness above the bendable portion 103 in the opening 130, which is the light-emitting area of ​​the lighting device 5, becomes stronger than the brightness above the non-bendable portion 101 and the non-bendable portion 102, while the brightness above the portion of the non-bendable portion 102 closest to the bendable portion 103 becomes weaker than the brightness above the non-bendable portion 101 and the brightness above the central part of the non-bendable portion 102.

[0033] Figures 5(a) to 5(c) show the structure of a comparative example lighting device 6, which was designed based on the lighting device 5 to reduce light leakage at the bent portion 103. This lighting device 6 is also the device that formed the basis for the invention of the lighting device 1 according to the first embodiment of the present invention.

[0034] Figure 5(a) is a top view of the light guide 10 and housing 11 of the lighting device 6, with the position of the edge of the opening 130 of the cover 13 indicated by a dotted line. Figure 5(b) is a cross-sectional view of the non-bent portion 101 and its surroundings, cut at the position of the cutting line B1-B1 shown in Figure 5(a). The cross-section of the non-bent portion 102 and its surroundings is the same as that shown in Figure 5(b). Figure 5(c) is a cross-sectional view of the bent portion 103 and its surroundings, cut at the position of the cutting line B2-B2 shown in Figure 5(a).

[0035] In the structure of the lighting device 6 shown in Figures 5(a) to (c), when viewed from the overlapping direction of the light guide 10 and the cover 13 (up and down direction in Figures 5(b) and (c)), the position of the bent portion 103 of the light guide 10 does not overlap with the position of the opening 130 (part 133) of the cover 13. By covering the upper part of the bent portion 103 with the cover 13, the generation of light leakage at the bent portion 103 can be suppressed.

[0036] However, on the other hand, the light emitted from the bent portion 103 is more easily blocked by the cover 13, so the brightness above the bent portion 103 and the brightness above the part of the non-bent portion 102 that is close to the bent portion 103 in the opening 130, which is the light-emitting area of ​​the lighting device 6, become weaker than the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102.

[0037] Figures 6(a) to 6(c) show the structure of the lighting device 1 according to the first embodiment of the present invention, in which the structure of the lighting device 6 is improved to increase the amount of light extracted from the aperture 130 emitted from the bent portion 103.

[0038] Figure 6(a) is a top view of the light guide 10 and housing 11 of the lighting device 1, with the position of the edge of the opening 130 of the cover 13 indicated by a dotted line. Figure 6(b) is a cross-sectional view of the non-bent portion 101 and its surroundings, cut at the position of the cutting line C1-C1 shown in Figure 6(a). The cross-section of the non-bent portion 102 and its surroundings is the same as that shown in Figure 6(b). Figure 6(c) is a cross-sectional view of the bent portion 103 and its surroundings, cut at the position of the cutting line C2-C2 shown in Figure 6(a).

[0039] In the lighting device 1, when viewed from the overlapping direction of the light guide 10 and the cover 13 (up and down direction in Figures 6(b) and (c)), the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133), or the overlap width between the position of the bent portion 103 and the position of the opening 130 (part 133) is smaller than the overlap width W1 between the positions of the non-bent portions 101 and 102 and the positions of the opening 130 (parts 131 and 132). As a result, similar to the lighting device 6, the generation of light leakage at the bent portion 103 can be suppressed.

[0040] To more effectively suppress the generation of light leakage at the bent portion 103, it is preferable that the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133) when viewed from the direction in which the light guide 10 and the cover 13 overlap, as shown in Figure 6(c).

[0041] Furthermore, in the lighting device 1, as a structure to increase the amount of light emitted from the bent portion 103 and taken out of the aperture 130, a structure is provided, as shown in Figure 6(c), in which a gap 16 exists between the bent portion 103 and the housing 11, where at least a portion of the position overlaps with the position of the aperture 130 when viewed from the overlapping direction of the light guide 10 and the cover 13.

[0042] In the example shown in Figure 6(a), the gap 16 is formed by making the curvature of the outer edge of portion 113 of the housing 11 greater than the curvature of the outer edge of the bent portion 103 of the light guide 10.

[0043] As shown in Figure 6(c), the gap 16 is a space formed between the outer edge of the bent portion 103 and the inner surface of the side wall portion 115 of the housing 11, extending along the length of the bent portion 103. Because the opening 130 (part 133) is located above this gap 16, the amount of light emitted from the bent portion 103 into the gap 16 can be reflected upward by the inner surface of the housing 11, thereby increasing the amount of light taken out of the opening 130 (part 133) from the bent portion 103.

[0044] As a result, the brightness above the bent portion 103 and the brightness above the portion of the non-bent portion 102 that is close to the bent portion 103 in the opening 130, which is the light-emitting area of ​​the lighting device 1, becomes stronger, and the difference between the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102 becomes smaller. In other words, the uniformity of the brightness of the light-emitting area of ​​the lighting device 1 is improved.

[0045] Furthermore, in order to efficiently send light from the gap 16 to the opening 130 (part 133), it is preferable that the inner surface 116 near the boundary between the bottom 114 of the housing 11 and the outer edge side wall 115 be a curved surface that bulges outward, as shown in Figure 6(c), which makes it easier to reflect light upward (towards the lens 12).

[0046] The overlap width W2 between the position of the gap 16 and the position of the opening 130 when viewed from the overlapping direction of the light guide 10 and the cover 13 is appropriately adjusted so that the brightness above the bent portion 103 and the brightness above the portion of the non-bent portion 102 that is close to the bent portion 103 in the opening 130 are close to the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102.

[0047] Typically, as shown in Figure 6(b), there is no gap between the non-bending portions 101 and 102 and the housing 11 (parts 111 and 112) that coincides with the position of the opening 130 (parts 131 and 132) when viewed from the overlapping direction of the light guide 10 and the cover 13. A gap of a width that does not significantly affect the amount of light emitted from the non-bending portions 101 and 102 to exit the opening 130 (parts 131 and 132) may exist, but it is usually unnecessary.

[0048] (Effects of the first embodiment) According to the first embodiment of the present invention, the lighting device 1 includes a structure for suppressing light leakage at the bent portion 103 of the light guide 10, and a structure using a gap 16 that can suppress the reduction in brightness around the bent portion 103 caused by the structure for suppressing light leakage, thereby improving the uniformity of the brightness of the light-emitting region.

[0049] In the lighting device 1, the greater the curvature of the bent portion 103 of the light guide 10, the greater the amount of light leakage at the bent portion 103. Therefore, the lighting device 1, which can suppress the decrease in brightness uniformity caused by this light leakage, can be suitably used in installation locations where the curvature of the bent portion 103 tends to be large, such as interior parts of vehicles that are close to a rectangle, such as the center console lid. The same applies to the lighting devices 2 and 3 according to the second and third embodiments described later.

[0050] [Second Embodiment] The lighting device 2 according to the second embodiment of the present invention differs from the lighting device 1 according to the first embodiment in that it has a structure that increases the amount of light emitted from the bending portion 103 and taken out from the aperture 130. Hereinafter, the same configuration as that of the lighting device 1 according to the first embodiment may be omitted or simplified in the description.

[0051] Figures 7(a) to 7(c) show the structure of a lighting device 2 according to a second embodiment of the present invention, in which the structure of the lighting device 6 is improved to increase the amount of light emitted from the bent portion 103 and taken out from the aperture 130.

[0052] Figure 7(a) is a top view of the light guide 10 and housing 11 of the lighting device 2, with the position of the edge of the opening 130 of the cover 13 indicated by a dotted line. Figure 7(b) is a cross-sectional view of the non-bent portion 101 and its surroundings, cut at the position of the cutting line D1-D1 shown in Figure 7(a). The cross-section of the non-bent portion 102 and its surroundings is the same as that shown in Figure 7(b). Figure 7(c) is a cross-sectional view of the bent portion 103 and its surroundings, cut at the position of the cutting line D2-D2 shown in Figure 7(a).

[0053] In the lighting device 2, similar to the lighting device 1 according to the first embodiment, when viewed from the overlapping direction of the light guide 10 and the cover 13 (up and down direction in Figures 7(b) and (c)), the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133), or the overlap width between the position of the bent portion 103 and the position of the opening 130 (part 133) is smaller than the overlap width W1 between the positions of the non-bent portions 101 and 102 and the positions of the opening 130 (parts 131 and 132). As a result, similar to the lighting device 6, the generation of light leakage at the bent portion 103 can be suppressed.

[0054] To more effectively suppress the generation of light leakage at the bent portion 103, it is preferable that the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133) when viewed from the direction in which the light guide 10 and the cover 13 overlap, as shown in Figure 7(c).

[0055] Furthermore, in the lighting device 2, as a structure to increase the amount of light emitted from the bent portion 103 and taken out of the aperture 130, as shown in Figure 7(c), the flat surface 105 of the bent portion 103 is inclined in a direction toward the aperture 130 (part 133) from a plane parallel to the cover 13 (horizontal plane in Figure 7(c)) in a cross section perpendicular to the longitudinal direction of the light guide 10.

[0056] In a cross-section perpendicular to the length of the light guide 10 of the lighting device 2, the opening 130 (part 133) is located diagonally above the bent portion 103, as shown in Figure 7(c). Therefore, in order to efficiently extract light from the opening 130 (part 133), in a cross-section perpendicular to the length of the light guide 10, the flat surface 105 of the bent portion 103 is inclined from a surface parallel to the cover 13 toward the opening 130.

[0057] As a result, the brightness above the bent portion 103 and the brightness above the portion of the non-bent portion 102 that is close to the bent portion 103 in the light-emitting area of ​​the opening 130 of the lighting device 2 become stronger, and the difference between the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102 becomes smaller. In other words, the uniformity of the brightness of the light-emitting area of ​​the lighting device 2 is improved.

[0058] The inclination angle of the flat surface 105 in the bent portion 103 is adjusted as appropriate so that the brightness above the bent portion 103 in the opening 130 and the brightness above the portion of the non-bent portion 102 that is close to the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102 are close to the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102.

[0059] Typically, as shown in Figure 7(b), the flat surfaces 105 in the non-bent sections 101 and 102 are parallel to the cover 13. The flat surfaces 105 in the non-bent sections 101 and 102 may have an inclination at an angle that does not significantly affect the amount of light extracted from the aperture 130 (parts 131 and 132) of the non-bent sections 101 and 102, but this is usually unnecessary.

[0060] The inclination angle of the flat surface 105 may change continuously along the length of the light guide 10 between the non-bent sections 101, 102 and the bent section 103, or it may switch discontinuously at the boundary between the non-bent sections 101, 102 and the bent section 103.

[0061] (Effects of the second embodiment) According to the second embodiment of the present invention, the lighting device 2 includes a structure for suppressing light leakage at the bent portion 103 of the light guide 10, and a structure in which the flat surface 105 of the bent portion 103 is inclined toward the opening 130, which can suppress the reduction in brightness around the bent portion 103 caused by the structure for suppressing light leakage, thereby improving the uniformity of brightness in the light-emitting region.

[0062] [Third Embodiment] The lighting device 3 according to the third embodiment of the present invention differs from the lighting device 1 according to the first embodiment in that it has a structure that increases the amount of light emitted from the bending portion 103 and taken out from the aperture 130. Hereinafter, the same configuration as that of the lighting device 1 according to the first embodiment may be omitted or simplified in the description.

[0063] Figures 8(a) to 8(c) show the structure of a lighting device 3 according to a third embodiment of the present invention, in which the structure of the lighting device 6 is improved to increase the amount of light emitted from the bent portion 103 and taken out from the aperture 130.

[0064] Figure 8(a) is a top view of the light guide 10 and housing 11 of the lighting device 3, with the position of the edge of the opening 130 of the cover 13 indicated by a dotted line. Figure 8(b) is a cross-sectional view of the non-bent portion 101 and its surroundings, cut at the position of the cutting line E1-E1 shown in Figure 8(a). The cross-section of the non-bent portion 102 and its surroundings is the same as that shown in Figure 8(b). Figure 8(c) is a cross-sectional view of the bent portion 103 and its surroundings, cut at the position of the cutting line E2-E2 shown in Figure 8(a).

[0065] In the lighting device 3, similar to the lighting device 1 according to the first embodiment, when viewed from the overlapping direction of the light guide 10 and the cover 13 (up and down direction in Figures 8(b) and (c)), the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133), or the overlap width between the position of the bent portion 103 and the position of the opening 130 (part 133) is smaller than the overlap width W1 between the positions of the non-bent portions 101 and 102 and the positions of the opening 130 (parts 131 and 132). As a result, similar to the lighting device 6, the generation of light leakage at the bent portion 103 can be suppressed.

[0066] To more effectively suppress the generation of light leakage at the bent portion 103, it is preferable that the position of the bent portion 103 does not overlap with the position of the opening 130 (part 133) when viewed from the direction in which the light guide 10 and the cover 13 overlap, as shown in Figure 8(c).

[0067] Furthermore, in the lighting device 3, as a structure to increase the amount of light emitted from the bent portion 103 and taken out of the aperture 130, a structure is provided, as shown in Figure 8(c), in which a linear projection 124 is formed on the portion 123 covering the bent portion 103 of the lens 12, and which fits inside the aperture 130 (portion 133).

[0068] By using the projection 124, the light emitted from the bent portion 103 of the light guide 10 and entering the inside of the lens 12 (part 123) can be efficiently guided to the aperture 130 (133).

[0069] As a result, the brightness above the bent portion 103 and the brightness above the portion of the non-bent portion 102 that is close to the bent portion 103 in the light-emitting area of ​​the lighting device 3 become stronger, and the difference between the brightness above the non-bent portion 101 and the brightness above the central part of the non-bent portion 102 becomes smaller. In other words, the uniformity of the brightness of the light-emitting area of ​​the lighting device 3 is improved.

[0070] As shown in Figure 8(b), it is not necessary to form the protrusions 124 on the parts 121 and 122 of the lens 12 that cover the non-bending portions 101 and 102 of the light guide 10, but they may be formed. Since the light emitted from the non-bending portions 101 and 102 is already efficiently extracted from the opening 130 (parts 131 and 132), even if the protrusions 124 are provided on the parts 121 and 122 of the lens 12, the effect on the brightness above the non-bending portions 101 and 102 is small.

[0071] (Effects of the third embodiment) According to the third embodiment of the present invention, the illumination device 3 includes a structure for suppressing light leakage at the bent portion 103 of the light guide 10, and a structure using a projection 124 of the lens 12 that can suppress the reduction in brightness around the bent portion 103 caused by the structure for suppressing light leakage, thereby improving the uniformity of the brightness of the light-emitting region.

[0072] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention. Furthermore, the components of the above embodiments can be arbitrarily combined without departing from the spirit of the invention. Moreover, the above embodiments do not limit the invention as defined in the claims. It should also be noted that not all combinations of features described in the embodiments are necessarily essential for solving the problem of the invention. [Explanation of Symbols]

[0073] 1, 2, 3 Lighting devices 10 Light guide 101, 102 Non-bending part 103 Bending section 105 Flat surface 11 Housing 117 recess 12 lenses 124 Protrusion 13 Cover 130 opening 14 Light source 16 gaps

Claims

1. A rod-shaped light guide having a bent portion and a non-bent portion, A light source that supplies light to the inside of the light guide, A housing that houses the light guide inside a linear recess, A cover having a linear opening for allowing light emitted from the light guide to pass through, A lens is installed between the light guide and the opening of the cover, Equipped with, When viewed from the overlapping direction of the light guide and the cover, the position of the bent portion does not coincide with the position of the opening, or the overlap width between the position of the bent portion and the position of the opening is smaller than the overlap width between the position of the non-bent portion and the position of the opening. A structure is provided to increase the amount of light emitted from the bent portion that is taken out of the opening. Lighting device.

2. The above structure is such that, when viewed from the overlapping direction of the light guide and the cover, there exists a gap between the bent portion and the housing in which at least a portion of the position overlaps with the position of the opening. The lighting device according to claim 1.

3. The above structure has a flat surface formed on the side surface of the light guide that extends along the length of the light guide, and in a cross section perpendicular to the length of the light guide, the flat surface at the bent portion is inclined in a direction toward the opening from a surface parallel to the cover. The lighting device according to claim 1.

4. The aforementioned structure is characterized in that a linear projection is formed in the portion of the lens that covers the bent portion and fits inside the opening. The lighting device according to claim 1.

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