Light guides and vehicle lighting fixtures

Abstract

To provide a light guide body, etc. that allow a corner part on the side opposite to a direction in which a first light guide part extends, to emit light.SOLUTION: A light guide body 30 guides light emitted by a light source 20. The light guide body includes a light incidence part 31, a first light guide part 32, and a second light guide part 33. The light incidence part is a light incidence part on which the light emitted by the light source is incident. The first light guide part is a light guide part extending from one end part toward the other end part, and for emitting light by using the light guided by the second light guide part, incident from the one end part, and guided toward the other end part in the first light guide part. The second light guide part is a light guide part connecting the light incidence part and the first light guide part, having a bent part whose inner surface is a total reflection surface, and for guiding the light incident from the light incidence part, to the one end part. In the second light guide part, an auxiliary light emission part 34 is formed in a direction different from a direction in which the first light guide part extends. The auxiliary light emission part emits light by using the light guided by the second light guide part and incident on the auxiliary light emission part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a light guide and a vehicle lamp, and particularly to a light guide and a vehicle lamp capable of emitting light from a corner portion on the side opposite to the direction in which the first light guide portion extends.

Background Art

[0002] There is known a vehicle lamp configured such that a light source is disposed near an end portion of a bar-shaped light guide portion extending in a longitudinal direction, and light from this light source is made to enter from the end portion of the light guide portion (for example, see Patent Document 1).

[0003] On the other hand, as shown in FIG. 13, the inventors of the present invention disposed a light source 220 at a position away from an end portion 232a of a bar-shaped first light guide portion 232 extending in a longitudinal direction (a position away in a direction intersecting with the direction in which the first light guide portion 232 extends), and provided a second light guide portion 233 that extends from in front of this light source 220 (for example, extends in a form that folds back in a U shape) and is integrally connected to the end portion 232a of the first light guide portion 232, and considered guiding the light from the light source 220 by this second light guide portion 233 and making it enter from the end portion 232a of the first light guide portion 232. FIG. 13 is an example of a light guide portion studied by the inventors of the present invention.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in such a case, there is a problem that light cannot be emitted from a corner portion on the side opposite to the direction in which the first light guide portion 232 extends (see the range indicated by reference sign L3 in FIG. 13).

[0006] The present invention was made to solve these problems, and aims to provide a light guide and a vehicle light fixture that can emit light from the corner opposite to the direction in which the first light guide extends. [Means for solving the problem]

[0007] The light guide according to the present invention is a light guide that guides light emitted by a light source, the light guide includes a light-receiving portion, a first light guide portion and a second light guide portion, the light-receiving portion is a light-receiving portion into which light emitted by the light source enters, the first light guide portion extends from one end toward the other end and is a light guide portion that emits light by the light that enters from the one end and is guided through the first light guide portion toward the other end, the second light guide portion connects the light-receiving portion and the first light guide portion and has a bent portion which is an inner surface total reflection surface and is a light guide portion that guides the light that enters from the light-receiving portion to the one end, an auxiliary light-emitting portion is formed in the second light guide portion in a direction different from the direction in which the first light guide portion extends, and the auxiliary light-emitting portion is a portion that emits light by the light that enters the auxiliary light-emitting portion and is guided by the second light guide portion.

[0008] This configuration allows the corner opposite to the direction in which the first light guide extends to emit light.

[0009] This is because the auxiliary light-emitting unit provided in the second light-guiding unit emits light when the light guided by the second light-guiding unit enters the auxiliary light-emitting unit.

[0010] Furthermore, in the light guide described above, the auxiliary light-emitting portion may include a front surface which is the light-emitting surface and a rear surface on the opposite side, and may be provided on the side opposite to the direction in which the first light guide portion extends.

[0011] Furthermore, in the above-mentioned light guide, the front surface of the auxiliary light-emitting section may be a flat surface.

[0012] Furthermore, in the above-mentioned light guide, the front surface of the auxiliary light-emitting portion may be a surface with a cross-sectional arc shape that is aligned with the front surface of the first light guide portion.

[0013] Furthermore, in the light guide described above, the rear surface of the auxiliary light-emitting section includes a first optical element and a second optical element, wherein the first optical element is a total reflection surface that totally reflects the light guided to the auxiliary light-emitting section by the second light guide and incident on the first optical element toward the second optical element, and the second optical element is a total reflection surface that totally reflects the light reflected from the first optical element and emits light from the front surface of the auxiliary light-emitting section.

[0014] Furthermore, in the light guide described above, the first optical element is formed as part of the inner wall of the recess by forming an inverted triangular recess on the rear surface of the auxiliary light-emitting portion, and the second optical element may be formed in the thick portion of the auxiliary light-emitting portion where the recess is not formed.

[0015] Furthermore, in the above-described light guide, the second light guide portion is a light guide portion in which one end is integrally connected to the light receiving portion and the other end is integrally connected to one end of the first light guide portion, and the bent portion may consist of a straight line, a curve, or a combination of a straight line and a curve with respect to the direction of light propagation.

[0016] Furthermore, in the above-mentioned light guide, the front surface which is the light-emitting surface of the auxiliary light guide portion may be given a textured finish.

[0017] Furthermore, in the above-mentioned light guide, with respect to the direction of light irradiation, the thickness of the auxiliary light-emitting portion may be thinner than the thickness of the second light guide portion.

[0018] The vehicle lighting device according to the present invention is a vehicle lighting device comprising a light source and a light guide as described in any of the above. [Effects of the Invention]

[0019] The present invention provides a light guide and a vehicle light fixture that can emit light from the corner opposite to the direction in which the first light guide extends. [Brief explanation of the drawing]

[0020] [Figure 1] It is a front view of the vehicle lamp 10. [Figure 2] It is a sectional view taken along the line A-A of FIG. 1 (partial sectional view). [Figure 3] It is a sectional view taken along the line B-B of FIG. 1. [Figure 4] It is an enlarged perspective view of the vicinity of the auxiliary light-emitting portion 34 of the light guide 30 as seen from the rear surface 34b side. [Figure 5] It is a front view of the light guide 30 (including the optical path diagram). [Figure 6] It is a sectional view taken along the line A-A of FIG. 1 (partial sectional view) (including the optical path diagram). [Figure 7] It is a front view of the vehicle lamp 10 in a state where the opening of the housing 50 is covered with the light-shielding member 60. [Figure 8] It is a front view of the vehicle lamp 100 of the comparative example. [Figure 9] It is a front view of the light guide 30A (modified example). [Figure 10] It is an enlarged perspective view of the vicinity of the auxiliary light-emitting portion 34A of the light guide 30A as seen from the rear surface 34Ab side. [Figure 11] It is a front view of the light guide 30A (modified example) (including the optical path diagram). [Figure 12] It is a sectional view taken along the line C-C of FIG. 9. [Figure 13] It is an example of the light guide portion studied by the present inventors.

[0021] Hereinafter, the vehicle lamp 10 using the light guide 30 which is an embodiment of the present invention will be described with reference to the accompanying drawings. In each figure, the corresponding components are denoted by the same reference numerals, and redundant explanations are omitted.

[0022] FIG. 1 is a front view of the vehicle lamp 10. FIG. 2 is a sectional view taken along the line A-A of FIG. 1 (partial sectional view). FIG. 3 is a sectional view taken along the line B-B of FIG. 1. FIG. 4 is an enlarged perspective view of the vicinity of the auxiliary light-emitting portion 34 of the light guide 30 as seen from the rear surface 34b side. FIG. 5 is a front view of the light guide 30 (including the optical path diagram). FIG. 6 is a sectional view taken along the line A-A of FIG. 1 (partial sectional view) (including the optical path diagram).

[0023] The vehicle light fixture 10 is a vehicle signal light fixture that functions as a taillight and is mounted on both the left and right sides of the rear end of a vehicle (not shown), such as an automobile. Since the vehicle light fixtures 10 mounted on both the left and right sides have a symmetrical configuration, the vehicle light fixture 10 mounted on the right side of the rear end of the vehicle (right side when facing the front of the vehicle) will be described below as a representative example. For the sake of explanation below, the X, Y, and Z axes will be defined as shown in Figure 1. The X axis extends in the longitudinal direction of the vehicle. The Y axis extends in the width direction of the vehicle. The Z axis extends in the vertical direction.

[0024] As shown in Figures 1 and 2, the vehicle light fixture 10 comprises a light source 20, a light guide 30 that guides the light emitted by the light source 20, a reflector 40 positioned behind the light guide 30, and a housing 50 positioned behind the reflector 40. The reflector 40 is preferably made of white resin in order to reflect the light that leaks from the light guide 30 to the reflector 40 side, making the vehicle light fixture 10 (light guide 30) appear brighter. Note that the reflector 40 is omitted in Figure 1.

[0025] The light source 20 is a semiconductor light-emitting element such as an LED that emits red light. The light source 20 is located at a distance from one end 32a of the first light guide 32 in a direction intersecting (for example, perpendicular) to the direction in which the first light guide 32 extends, for example, near the bottom of one end 32a of the first light guide 32. In this case, the light source 20 is attached to the reflector 40 (or housing 50) etc. with its light-emitting surface facing the rear of the vehicle and its optical axis extending in the X direction.

[0026] The light guide 30 is made of a transparent resin such as acrylic or polycarbonate, and as shown in Figure 1, it includes a light-receiving section 31, a first light-guiding section 32, and a second light-guiding section 33.

[0027] The light-receiving section 31 is a section into which light emitted from the light source 20 enters. The light-receiving section 31 is positioned in front of the light source 20 (light-emitting surface). Although not shown in the figures, the light-receiving section 31 includes a total reflection surface that totally reflects the light that enters from the light-receiving section 31 toward the second light guide section 33 (one end 33a).

[0028] The first light guide section 32 is a rod-shaped light guide section (light guide rod) that extends from one end 32a located on the inside in the vehicle width direction toward the other end 32b located on the outside in the vehicle width direction, and emits light when light is guided by the second light guide section 33, enters from the one end 32a, and is guided through the first light guide section 32 toward the other end 32b.

[0029] The following describes an example in which a light guide rod with a circular cross-sectional shape (see Figure 3) is used as the first light guide portion 32, based on a plane (XZ plane) perpendicular to the longitudinal direction (Y direction). However, the first light guide portion 32 may also be a light guide rod with a cross-sectional shape other than a circle, such as a ginkgo leaf-shaped light guide rod, based on a plane (XZ plane) perpendicular to the longitudinal direction (Y direction). For example, a light guide rod with a ginkgo leaf-shaped cross-section is described in Japanese Patent Application Publication No. 2017-41368.

[0030] As shown in Figure 2, the outer surface of the first light guide unit 32 includes a front surface 32c located on the rear side of the vehicle and a rear surface 32d located on the opposite side (front side of the vehicle).

[0031] As shown in Figure 3, the front surface 32c of the first light guide unit 32 has a cylindrical surface with a cross-sectional shape that is convex toward the rear of the vehicle, determined by a plane (XZ plane) perpendicular to the longitudinal direction (Y direction). On the other hand, the rear surface 32d of the first light guide unit 32 is a flat surface and includes a plurality of lens cut surfaces LC1 (also called light guide cuts) that cause light Ray1 (see Figures 5 and 6) guided through the first light guide unit 32 and incident on the rear surface 32d to undergo total internal reflection (diffuse reflection) and emit light from the front surface 32c of the first light guide unit 32 (see Figure 6).

[0032] The lens cut surface LC1 is a total reflection surface formed, for example, by providing a V-groove (for example, a V-groove extending in the Z direction) on the rear surface 32d of the first light guide portion 32. The lens cut surface LC1 is provided in the area indicated by the reference numeral L1 in Figure 1.

[0033] The second light guide section 33 is a light guide that guides light that enters the second light guide section 33 from the light receiving section 31 and enters the second light guide section 33 by total reflection to one end 32a of the first light guide section 32. The second light guide section 33 connects the light receiving section 31 and the first light guide section 32 and has a bent section (or a bent section including an inner totally reflective surface) which is an inner totally reflective surface. The bent section may be, for example, a straight line, a curve, or a combination of a straight line and a curve with respect to the direction of propagation of the light Ray 1. Specifically, as shown in Figure 1, the second light guide section 33 is a curved light guide section (for example, a shape that is curved in a convex U shape toward the inside in the vehicle width direction) with one end 33a integrally connected to the light receiving section 31 and the other end 33b integrally connected to one end 32a of the first light guide section 32.

[0034] The second light guide section 33 includes an auxiliary light-emitting section 34. The auxiliary light-emitting section 34 is formed in a direction different from the direction in which the first light guide section 32 extends, and is a portion that emits light when light rays 2 and 3 (see Figures 5 and 6) are guided by the second light guide section 33 and enter the auxiliary light-emitting section 34.

[0035] As shown in Figure 2, the auxiliary light-emitting section 34 includes a front surface 34a, which is the light-emitting surface located on the rear side of the vehicle, and a rear surface 34b, which is located on the opposite side (front side of the vehicle). The auxiliary light-emitting section 34 is provided at the corner opposite to the direction in which the first light guide section 32 extends (on the extension line of the first light guide section 32) (see Figure 1). The front surface 34a of the auxiliary light-emitting section 34 is, for example, a flat surface. The front surface 34a of the auxiliary light-emitting section 34 is subjected to a textured finish (multiple minute irregularities).

[0036] As shown in Figure 2, with respect to the light irradiation direction, the thickness T1 of the auxiliary light-emitting section 34 (thickness between the front surface 34a and the rear surface 34b) is thinner than the thickness T2 of the second light-guiding section 33. Furthermore, the auxiliary light-emitting section 34 is provided such that one end edge (the right end edge in Figure 2) is integrally connected to the second light-guiding section 33.

[0037] As shown in Figures 2 and 4, the rear surface 34b of the auxiliary light-emitting section 34 includes a total reflection surface TRef1 and a lens cut surface LC2 (also called a light guide cut).

[0038] The total reflection surface TRef1 is a total reflection surface that guides light Ray2 (see Figures 4 and 6) to the auxiliary light-emitting section 34 by the second light-guiding section 33 and incident on the total reflection surface TRef1, and totally reflects the light toward the lens cut surface LC2. The total reflection surface TRef1 is an example of the first optical element of the present invention.

[0039] The total reflective surfaces TRef1 (four total reflective surfaces TRef1 are shown as examples in Figure 4) are formed as part of the inner wall of the inverted triangular recess 34c (non-cut area) formed on the rear surface 34b of the auxiliary light-emitting unit 34. Note that the total reflective surfaces TRef1 are not limited to four, but may be 1 to 3, or 5 or more. The total reflective surfaces TRef1 are arranged in a stepped manner from the base side (second light guide unit 33 side) of the rear surface 34b of the auxiliary light-emitting unit 34 toward the inside in the vehicle width direction and diagonally upward (upward to the right in Figure 4). Connecting surfaces 34d are provided between the total reflective surfaces TRef1. Note that the inclination angle of the total reflective surfaces TRef1 may be an appropriate inclination angle.

[0040] The lens cut surfaces LC2 (four lens cut surfaces LC2 are shown as examples in Figure 4) are total reflection surfaces that totally reflect the light reflected from the total reflection surface TRef1 and emit light from the front surface 34a of the auxiliary light-emitting section 34. Note that the number of lens cut surfaces LC2 is not limited to four, but may be 1 to 3, or 5 or more. The lens cut surfaces LC2 are an example of the second optical element of the present invention.

[0041] The lens cut surface LC2 is formed in the thick portion of the auxiliary light-emitting section 34 where the recess 34c is not formed (the region on the vehicle width side (right side in Figure 4) of the rear surface 34b of the auxiliary light-emitting section 34 relative to the total reflection surface TRef1). The lens cut surface LC2 is a total reflection surface formed, for example, by applying a V-groove (for example, a V-groove extending in the Z direction) to the rear surface 34b of the auxiliary light-emitting section 34. The depth h of the V-groove (see Figure 2) is deeper for V-grooves that are farther from the first light guide section 32 (one end 32a). As a result, even if the total reflection surface TRef1 is far from the first light guide section 32 (one end 32a), the reflected light from the total reflection surface TRef1 can be totally reflected and emitted from the front surface 34a of the auxiliary light-emitting section 34.

[0042] Next, with reference to Figures 5 and 6, we will explain the optical path taken by the light emitted from the light source 20.

[0043] In the vehicle lighting device 10 with the above configuration, when the light source 20 is turned on, the light emitted from the light source 20 enters through the light receiving section 31.

[0044] As shown in Figure 5, some of the light Ray 1 that enters from the light-receiving section 31 is guided by the second light guide section 33 to one end 32a of the first light guide section 32, and travels through the first light guide section 32 toward the other end 32b while repeatedly undergoing internal reflection. At that time, as shown in Figure 6, the light Ray 1 incident on the rear surface 32d (lens cut surface LC1) of the first light guide section 32 is totally reflected (diffuse reflected) by the lens cut surface LC1 and exits from the front surface 32c of the first light guide section 32. As a result, the first light guide section 32 emits light.

[0045] Furthermore, as shown in Figure 5, some of the light rays Ray2 and Ray3 that enter from the light-receiving section 31 are guided to the auxiliary light-emitting section 34 by the second light-guiding section 33.

[0046] As shown in Figures 4 and 5, the light Ray 2 guided by the second light guide 33 to the auxiliary light-emitting unit 34 and incident on the total reflection surface TRef1 is totally reflected by the total reflection surface TRef1 toward the inside in the vehicle width direction (lens cut surface LC2). As shown in Figure 6, the light Ray 2 totally reflected by the total reflection surface TRef1 is further totally reflected (diffuse reflected) by the lens cut surface LC2 and emitted from the front surface 34a of the auxiliary light-emitting unit 34 (mainly the region facing the lens cut surface LC2) (see Figure 6).

[0047] Furthermore, as shown in Figures 4 to 6, the light Ray 3 guided by the second light guide 33 to the auxiliary light-emitting unit 34 and entering the thin portion of the auxiliary light-emitting unit 34 (the portion between the bottom surface of the recess 34c and the front surface 34a of the auxiliary light-emitting unit 34) is emitted from the front surface 34a of the auxiliary light-emitting unit 34 (mainly the region facing the recess 34c). In addition, some of the light that leaks from the light guide 30 to the reflector 40 side and is reflected by the white resin reflector 40 (diffuse light reflected by the white resin) also passes through the thin portion of the auxiliary light-emitting unit 34 (the portion between the bottom surface of the recess 34c and the front surface 34a of the auxiliary light-emitting unit 34) and is emitted from the front surface 34a of the auxiliary light-emitting unit 34. As described above, the auxiliary light-emitting unit 34 emits light when light Rays 2, 3, etc. are emitted from the front surface 34a of the auxiliary light-emitting unit 34. In this case, the front surface 34a of the auxiliary light-emitting section 34 is subjected to a textured finish (multiple minute bumps and depressions), which allows the auxiliary light-emitting section 34 to emit light uniformly (or nearly uniformly). Furthermore, by increasing the thickness T1 (see Figure 2) of the auxiliary light-emitting section 34, the amount of light entering the auxiliary light-emitting section 34 increases, making the auxiliary light-emitting section 34 emit light more brightly. On the other hand, increasing the thickness T1 (see Figure 2) of the auxiliary light-emitting section 34 reduces the amount of light entering the first light guide section 32, but by increasing the density of the lens cut LC1 provided in the range indicated by the symbol L1 in Figure 1, the first light guide section 32 can emit light more brightly.

[0048] Figure 7 is a front view of the vehicle light fixture 10 with the opening of the housing 50 covered by the light-shielding member 60.

[0049] As shown in Figure 7, by covering the opening of the housing 50 with a light-shielding member 60 (for example, an extension) having an opening 51 (through hole) formed therein that exposes the front surface 32c of the first light guide 32 and the front surface 34a of the auxiliary light-emitting part 34, a linear light-emitting part can be formed by the front surface 32c of the first light guide 32 and the front surface 34a of the auxiliary light-emitting part 34 that are exposed through the opening 51 (through hole). The light-shielding member 60 is attached to, for example, the reflector 40 (or housing 50).

[0050] Next, the effects of the vehicle lighting fixture 10 with the above configuration will be explained in comparison with a comparative example.

[0051] Figure 8 is a front view of the comparative vehicle lighting fixture 100.

[0052] The comparative example vehicle light fixture 100 includes a light source 120 and a light guide 130 that guides the light emitted by the light source 120.

[0053] The light source 120 is positioned so that its light-emitting surface faces one end 132a (light-receiving portion) of the light guide 130.

[0054] The light guide 130 is a long light guide rod extending in the Y direction from one end 132a located on the inside in the vehicle width direction to the other end 132b located on the outside in the vehicle width direction, and the second light guide section 33 is omitted. Otherwise, the light guide 130 has the same configuration as the first light guide section 32.

[0055] In the comparative example vehicle light fixture 100, the light source 120 is positioned on the opposite side from the direction in which the light guide 130 extends, so it is not possible to illuminate the area indicated by the symbol L2 in Figure 8. In other words, the area indicated by the symbol L2 becomes a dark area where no light is emitted.

[0056] Therefore, for example, although not shown in the diagram, when a lid lamp (provided on a movable part such as the trunk lid of a vehicle) is placed adjacent to the left side of the vehicle light fixture 100 in Figure 8 (with the trunk lid closed), a dark area (at least the dark area indicated by the symbol L2 in Figure 8) is formed between the light-emitting part formed by turning on the light source 120 (a linear light-emitting part composed of the front surface of the light guide 130 exposed from the opening 51) and the light-emitting part formed by turning on the lid lamp. This dark area is mainly formed by the thickness of the substrate K on which the light source 120 is mounted, and by providing a space between the light source 120 and one end 132a (light-receiving part) of the light guide 130 to prevent melting of the end 132a (light-receiving part) of the light guide 130. As a result, there is a problem that the vehicle light fixture 100 (light guide 130) and the lid lamp cannot be made to appear as if they are emitting light as a single unit.

[0057] In contrast, in the vehicle lighting device 10 with the above configuration, the auxiliary light-emitting section 34 is positioned on the opposite side from the direction in which the first light guide section 32 extends (see Figure 7), so that the range indicated by the symbol L2 in Figure 8 can be illuminated.

[0058] Therefore, for example, although not shown in the diagram, when a lid lamp (provided on a movable part such as the trunk lid of a vehicle) is placed adjacent to the left side of the vehicle light fixture 10 in Figure 7 (with the trunk lid closed), the formation of a dark area (at least the dark area indicated by the symbol L2 in Figure 8) between the light-emitting area formed by lighting the light source 20 and the light-emitting area formed by lighting the lid lamp is suppressed. As a result, the vehicle light fixture 10 (a linear light-emitting area composed of the front surface 32c of the first light guide 32 and the front surface 34a of the auxiliary light-emitting area 34 exposed from the opening 51) and the lid lamp can be made to appear as if they are emitting light as a single unit.

[0059] As described above, according to this embodiment, the corner opposite to the direction in which the first light guide portion 32 extends can be made to emit light.

[0060] This is because the auxiliary light-emitting unit 34 provided in the second light-guiding unit 33 emits light in response to the light rays Ray 2 and 3 (see Figures 4 to 6) that are guided by the second light-guiding unit 33 and enter the auxiliary light-emitting unit 34.

[0061] Next, I will explain some variations.

[0062] In the above embodiment, an example was described in which the front surface 34a of the auxiliary light-emitting unit 34 was given a textured finish, but the embodiment is not limited to this. The textured finish may be omitted.

[0063] Furthermore, although the above embodiment describes an example in which a total reflection surface TRef1 and a lens cut surface LC2 are provided on the rear surface 34b of the auxiliary light-emitting unit 34, the embodiment is not limited to this. For example, the rear surface 34b of the auxiliary light-emitting unit 34 may be a flat surface without the total reflection surface TRef1 and the lens cut surface LC2.

[0064] Next, a modified example of the light guide 30 will be described. Hereafter, it will be referred to as light guide 30A.

[0065] Figure 9 is a front view of the light guide 30A (modified version). Figure 10 is an enlarged perspective view of the vicinity of the auxiliary light-emitting section 34A of the light guide 30A, viewed from the rear surface 34Ab side. Figure 11 is a front view of the light guide 30A (modified version) (including the optical path diagram). Figure 12 is a cross-sectional view of the CC of Figure 9.

[0066] The light guide 30A is made of a transparent resin such as acrylic or polycarbonate, and as shown in Figure 9, it includes a light-receiving section 31, a first light-guiding section 32, and a second light-guiding section 33A. The following explanation will focus on the differences from the light guide 30. Components identical to those of the light guide 30 are denoted by the same reference numerals, and explanations will be omitted as appropriate.

[0067] The second light guide section 33A is a light guide section that guides light that has entered from the light receiving section 31 to one end 32a of the first light guide section 32. Specifically, the second light guide section 33A is a linear light guide section extending in the Z direction, with one end 33Aa integrally connected to the light receiving section 31 and the other end 33Ab integrally connected to one end 32a of the first light guide section 32 via a total reflection surface TRef2 (45° inclined surface).

[0068] The second light guide section 33A includes an auxiliary light-emitting section 34A. The auxiliary light-emitting section 34A is the part that emits light when light Ray2 (see Figures 11 and 12) is guided by the second light guide section 33A and enters the auxiliary light-emitting section 34A.

[0069] As shown in Figure 10, the auxiliary light-emitting section 34A includes a front surface 34Aa, which is a light-emitting surface located on the rear side of the vehicle, and a rear surface 34Ab, which is located on the opposite side (front side of the vehicle). The auxiliary light-emitting section 34A is provided at the corner opposite to the direction in which the first light guide section 32 extends (on the extension line of the first light guide section 32).

[0070] As shown in Figures 10 and 12, the auxiliary light-emitting section 34A is provided integrally connected to the second light guide section 33A. The front surface 34Aa of the auxiliary light-emitting section 34A is, for example, a surface with a circular arc cross-section along the front surface 32c of the first light guide section 32. Similarly, the rear surface 34Ab of the auxiliary light-emitting section 34A is also a surface with a circular arc cross-section.

[0071] In the vehicle lighting device 10 using the light guide 30A configured as described above, when the light source 20 is turned on, the light emitted by the light source 20 enters through the light receiving section 31.

[0072] As shown in Figure 11, some of the light Ray 1 that enters from the light-receiving section 31 is guided by the second light guide section 33A to one end 32a of the first light guide section 32, and travels through the first light guide section 32 toward the other end 32b (omitted in Figure 11) while repeatedly undergoing internal reflection. At that time, as shown in Figure 5, the light Ray 1 incident on the rear surface 32d (lens cut surface LC1) of the first light guide section 32 is totally reflected (diffuse reflected) by the lens cut surface LC1 and exits from the front surface 32c of the first light guide section 32. As a result, the first light guide section 32 emits light.

[0073] Furthermore, some of the light Ray2 that enters from the light-receiving section 31 is guided to the auxiliary light-emitting section 34 by the second light-guiding section 33A.

[0074] The light Ray 2 (see Figure 11), guided by the second light guide 33A to the auxiliary light-emitting unit 34A, is emitted from the front surface 34Aa of the auxiliary light-emitting unit 34A (see Figure 12). As a result, the auxiliary light-emitting unit 34A emits light.

[0075] In addition, as with the above embodiment, the light guide 30A of this modified example may also have a textured surface (multiple minute irregularities) on the front surface 34Aa of the auxiliary light-emitting section 34A. Furthermore, as with the above embodiment, the light guide 30A of this modified example may also have a total reflection surface TRef1 and a lens cut surface LC2 on the rear surface 34Ab of the auxiliary light-emitting section 34A.

[0076] Furthermore, although the above embodiment describes an example in which one end edge (right end edge in Figure 2) of the auxiliary light-emitting section 34 is integrally connected to the second light guide section 33, the invention is not limited to this. For example, one end edge of the auxiliary light-emitting section 34 may be integrally connected to the portion of the second light guide section 33 that is closer to the rear of the vehicle (downward in Figure 2), or it may be integrally connected to the portion of the second light guide section 33 between the portion closer to the front of the vehicle and the portion closer to the rear of the vehicle.

[0077] Furthermore, in the above embodiment, an example was described in which the auxiliary light-emitting section 34 is provided at the corner opposite to the direction in which the first light guide section 32 extends (on the extension line of the first light guide section 32) (see Figure 1), but this is not limited to this. In other words, the auxiliary light-emitting section 34 may be provided at any part of the second light guide section 33.

[0078] Furthermore, although the above embodiment described an example in which a rod-shaped light guide (light guide rod) was used as the first light guide 32, the invention is not limited to this. For example, a plate-shaped light guide may be used as the first light guide 32.

[0079] Furthermore, although the above embodiment describes an example in which the vehicle lighting device of the present invention is applied to a taillight, the invention is not limited to this. For example, the vehicle lighting device of the present invention may be applied to other vehicle signaling lights such as rear lamps, position lamps, front combination lamps, rear combination lamps, position lamps, side marker lamps, headlights, etc.

[0080] The numerical values ​​shown in each of the embodiments described above are all examples, and it goes without saying that other appropriate numerical values ​​can be used.

[0081] The embodiments described above are merely illustrative in all respects. The invention is not to be construed as being limited by the descriptions of the embodiments above. The invention can be carried out in various other ways without departing from its spirit or main features. [Explanation of symbols]

[0082] 10… Vehicle lamp, 20… Light source, 30, 30A… Light guide, 31… Light incident part, 32… First light guide part, 32a… One end part, 32b… Other end part, 32c… Front surface, 32d… Rear surface, 33… Second light guide part, 33A… Second light guide part, 33Aa… One end part, 33Ab… Other end part, 33a… One end part, 33b… Other end part, 34, 34A… Auxiliary light emitting part, 34Aa… Front surface, 34Ab… Rear surface, 34a… Front surface, 34b… Rear surface, 34c… Concave part, 34d… Connecting surface, 40… Reflector, 50… Housing, 51… Opening, 60… Light shielding member, LC1, LC2… Lens cut surface, TRef1, TRef2… Total reflection surface

Claims

1. A light guide that guides the light emitted by a light source, The light guide includes a light-receiving section, a first light-guiding section, and a second light-guiding section. The aforementioned light-receiving section is a light-receiving section into which light emitted from the light source enters, The first light guide portion extends from one end to the other end and is a light guide portion that emits light by the light guided by the second light guide portion, which enters from the one end and is guided through the first light guide portion toward the other end. The second light guide section connects the light receiving section and the first light guide section, and has a bent section which is an inner total reflection surface, and is a light guide section that guides the light that has entered from the light receiving section to the one end. The second light guide portion has an auxiliary light-emitting portion formed in a direction different from the direction in which the first light guide portion extends. The auxiliary light-emitting section is a part that emits light when light is guided by the second light-guiding section and enters the auxiliary light-emitting section. The auxiliary light-emitting section includes a front surface which is the light-emitting surface and a rear surface on the opposite side, and is provided on the side opposite to the direction in which the first light-guiding section extends. The front surface of the auxiliary light-emitting section is a light guide body having a cross-sectional arc shape along the front surface of the first light guide section.

2. A light guide that guides the light emitted by a light source, The light guide includes a light-receiving section, a first light-guiding section, and a second light-guiding section. The aforementioned light-receiving section is a light-receiving section into which light emitted from the light source enters, The first light guide portion extends from one end to the other end and is a light guide portion that emits light by the light guided by the second light guide portion, which enters from the one end and is guided through the first light guide portion toward the other end. The second light guide section connects the light receiving section and the first light guide section, and has a bent section which is an inner total reflection surface, and is a light guide section that guides the light that has entered from the light receiving section to the one end. The second light guide portion has an auxiliary light-emitting portion formed in a direction different from the direction in which the first light guide portion extends. The auxiliary light-emitting section is a part that emits light when light is guided by the second light-guiding section and enters the auxiliary light-emitting section. The auxiliary light-emitting section includes a front surface which is the light-emitting surface and a rear surface on the opposite side, and is provided on the side opposite to the direction in which the first light-guiding section extends. The rear surface of the auxiliary light-emitting section includes a first optical element and a second optical element. The first optical element is a total reflection surface that totally reflects the light guided by the second light guide to the auxiliary light-emitting section and incident on the first optical element toward the second optical element. The second optical element is a total reflection surface that totally reflects the light reflected from the first optical element and emits light from the front surface of the auxiliary light-emitting section. The first optical element is formed as part of the inner wall of the recess by forming an inverted triangular recess on the rear surface of the auxiliary light-emitting portion. The second optical element is a light guide formed in the thick portion of the auxiliary light-emitting section in which the recess is not formed.

3. The light guide according to claim 1 or 2, wherein the front surface of the auxiliary light-emitting section is a flat surface.

4. A light guide that guides the light emitted by a light source, The light guide includes a light-receiving section, a first light-guiding section, and a second light-guiding section. The aforementioned light-receiving section is a light-receiving section into which light emitted from the light source enters, The first light guide extends from one end to the other end, and is a light guide that emits light when the light guided by the second light guide enters from the one end, is guided within the first light guide toward the other end, and then exits from the front surface of the first light guide. The second light guide section connects the light receiving section and the first light guide section, and has a bent section which is an inner total reflection surface, and is a light guide section that guides the light that has entered from the light receiving section to the one end. The second light guide portion has an auxiliary light-emitting portion formed in a direction different from the direction in which the first light guide portion extends. The auxiliary light-emitting section is a part that emits light when light guided by the second light-guiding section enters the auxiliary light-emitting section and is emitted from the front surface of the auxiliary light-emitting section. The auxiliary light-emitting section includes a front surface which is the light-emitting surface and a rear surface on the opposite side, and is provided on the side opposite to the direction in which the first light-guiding section extends. The rear surface of the auxiliary light-emitting section includes a first optical element and a second optical element. The first optical element is a total reflection surface that totally reflects the light guided by the second light guide to the auxiliary light-emitting section and incident on the first optical element toward the second optical element. The second optical element is a total reflection surface that totally reflects the light reflected from the first optical element and emits light from the front surface of the auxiliary light-emitting section. With respect to the direction of light irradiation, the thickness of the auxiliary light-emitting section is thinner than the thickness of the second light-guiding section.

5. The rear surface of the auxiliary light-emitting section includes a first optical element and a second optical element. The first optical element is a total reflection surface that totally reflects the light guided by the second light guide to the auxiliary light-emitting section and incident on the first optical element toward the second optical element. The light guide according to claim 1, wherein the second optical element is a total reflection surface that totally reflects the light reflected from the first optical element and emits light from the front surface of the auxiliary light-emitting section.

6. The second light guide is a light guide having one end integrally connected to the light receiving portion and the other end integrally connected to one end of the first light guide. The light guide according to any one of claims 1 to 5, wherein the bent portion is a straight line, a curve, or a combination of a straight line and a curve with respect to the direction of light propagation.

7. The light guide according to any one of claims 1 to 6, wherein the front surface which is the light-emitting surface of the auxiliary light-emitting part is subjected to a textured finish.

8. With respect to the direction of light irradiation, the thickness of the auxiliary light-emitting portion is thinner than the thickness of the second light-guiding portion, as described in any one of claims 1 to 3, 5 to 7.

9. A vehicle light fixture comprising a light source and a light guide according to any one of claims 1 to 8.

Images