Vehicle lamp

Abstract

To provide a vehicle lamp capable of making a light guide body emit light evenly (or substantially evenly) even when using light source with Lambertian light distribution arranged together in one place as light sources.SOLUTION: A vehicle lamp 10 comprises: a light source 20 whose light distribution characteristic is Lambertian light distribution; and a light guide body 30 including a first plate-shaped light guide part 31 that includes a light-emission surface 31a facing a light irradiation direction and a surface opposite to the light-emission surface on which a lens cut for light extraction is formed, a second plate-shaped light guide part 32 that extends from one end edge part of the first plate-shaped light guide part toward the light source 20 and guides light emitted by the light source to the one end edge part of the first plate-shaped light guide part, and a light incident surface 33 that is provided at the end part of the second plate-shaped light guide part facing the light source and through which light from the light source is made incident.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle lamp. [Background technology]

[0002] A vehicle lamp is known that includes a plurality of light sources arranged in a row at regular intervals from the inside to the outside in the vehicle width direction, and a light guide arranged in front of the light sources, and is configured to guide light from the plurality of light sources through the light guide (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-120683 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in Patent Document 1, when light sources with Lambertian light distribution arranged in one place are used as the light source, the light emitted by the light source with Lambertian light distribution is relatively brighter near the optical axis and becomes relatively darker as it moves away from the optical axis, which poses a problem that it is difficult to make the light guide emit light uniformly (or approximately uniformly).

[0005] The present disclosure has been made to solve such problems, and aims to provide a vehicle lamp that can make a light guide emit light uniformly (or approximately uniformly) even when using light sources with Lambertian light distribution that are arranged in one place as the light source. [Means for solving the problem]

[0006] a second plate-shaped light guiding portion extending from one end edge of the first plate-shaped light guiding portion toward the light source and guiding light emitted by the light source to the one end edge of the first plate-shaped light guiding portion; and a light entrance surface provided at an end of the second plate-shaped light guiding portion opposite to the light source, through which light from the light source enters, the second plate-shaped light guiding portion having one side disposed on one side with respect to an optical axis of the light source and another side disposed on the other side with respect to the optical axis of the light source, the one side including a first side disposed near the light entrance surface and a second side disposed farther from the light entrance surface, the first side being configured to receive light from the light source that enters through the light entrance surface from a portion of the light source that is closer to the light entrance surface than the ... the other side surface is a first total reflection surface that totally reflects relatively bright light toward the other side surface, and the other side surface is a second total reflection surface that totally reflects the totally reflected light from the first total reflection surface toward the one end edge of the first plate-shaped light guiding part, and relatively bright light on one side with respect to the optical axis of the light source, of the light from the light source that enters from the light entrance surface, is totally reflected by the first total reflection surface and the second total reflection surface, in this order, and then enters the first plate-shaped light guiding part through the one end edge of the first plate-shaped light guiding part, is guided within the first plate-shaped light guiding part, is totally reflected by the lens cut, and exits from the light exit surface, and relatively bright light on the other side with respect to the optical axis of the light source, of the light from the light source that enters from the light entrance surface, enters the first plate-shaped light guiding part through the one end edge of the first plate-shaped light guiding part as direct light, is guided within the first plate-shaped light guiding part, is totally reflected by the lens cut, and exits from the light exit surface.

[0007] With this configuration, even if light sources with Lambertian light distribution arranged together in one place are used as the light source, it is possible to make the light guide emit light uniformly (or approximately uniformly).

[0008] In the above vehicle lamp, the light source includes at least two light sources that are arranged in the plate thickness direction of the second plate-shaped light guide and emit light of different colors.

[0009] In the above vehicle lamp, the light source includes at least two light sources that are arranged in a direction intersecting the plate thickness direction of the second plate-shaped light guide and that emit light of different colors. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a vehicle lamp that can make a light guide emit light uniformly (or approximately uniformly) even when using light sources with Lambertian light distribution that are arranged together in one place as light sources. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a front view of a vehicle V equipped with a vehicle lamp 10. FIG. [Figure 2] 1A is a perspective view of a vehicle lamp 10, and FIG. 1B is a front view thereof. [Figure 3] FIG. 2 is a top view of the vehicle lamp 10. [Figure 4] FIG. 2 is a side view of the vehicle lamp 10. [Figure 5] 1A and 1B are top views of a vehicle lamp 10, with the optical path of light emitted from a light source 20 indicated therein. [Figure 6] 1 is a modified example (partially enlarged view) of the vehicle lamp 10. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, a vehicle lamp 10 according to an embodiment of the present disclosure will be described with reference to the accompanying drawings. Corresponding components in each drawing are given the same reference numerals, and duplicated explanations will be omitted.

[0013] FIG. 1 is a front view of a vehicle V on which a vehicle lamp 10 is mounted.

[0014] The vehicle lamp 10 of this embodiment is a vehicle signal lamp that functions as a DRL lamp, a position lamp, or a turn lamp, and is mounted on each of the left and right sides of the front end of a vehicle V such as an automobile, as shown in Fig. 1. Note that the symbol HL in Fig. 1 represents a vehicle headlamp.

[0015] Since the vehicle lamps 10 mounted on both the left and right sides have a symmetrical configuration, the following description will be directed to the vehicle lamp 10 mounted on the left side of the front end of the vehicle V (left side as viewed from the front of the vehicle). For ease of explanation, X, Y, and Z axes are defined below. The X axis extends in the longitudinal direction of the vehicle, the Y axis extends in the width direction of the vehicle, and the Z axis extends vertically.

[0016] 2(a) is a perspective view of the vehicle lamp 10, FIG. 2(b) is a front view, FIG. 3 is a top view, and FIG. 4 is a side view.

[0017] As shown in FIGS. 2( a ) to 4 , the vehicle lamp 10 includes a light source 20 and an inner lens 30 .

[0018] The light source 20 includes a first light source 21A and a second light source 21B. The first light source 21A and the second light source 21B are mounted on the substrate 22 and arranged at an interval in the Z direction (the thickness direction of the second plate-shaped light-guiding section 32), as shown in FIG.

[0019] The first light source 21A is, for example, a semiconductor light emitting element such as an LED that emits white light and has a Lambertian light distribution characteristic. The first light source 21A has a light emitting surface (for example, a rectangular light emitting surface with a side length of 1 mm). The optical axis AX of the first light source 21A is 21A passes through the center of the light-emitting surface and extends in a direction perpendicular to the light-emitting surface. On the other hand, the second light source 21B is, for example, a semiconductor light-emitting element such as an LED that emits amber light and has a Lambertian light distribution characteristic. The second light source 21B has a light-emitting surface (for example, a rectangular light-emitting surface with a side of 1 mm). The optical axis AX of the second light source 21B 21B passes through the center of the light-emitting surface and extends in a direction perpendicular to the light-emitting surface.

[0020] The substrate on which the first light source 21A and the second light source 21B are mounted is, in top view, aligned with the optical axis of the first light source 21A. AX21A (and the optical axis of the second light source 21B AX21B ) is attached to a housing (not shown) or the like in a state where it is tilted at an angle θ1 with respect to the X axis.

[0021] As described above, the light sources 20 (first light source 21A, second light source 21B) are arranged together in one location due to installation space limitations. Note that "one location" refers to a spacing of approximately 5 mm or less between the light sources, which is adjusted appropriately depending on the shape and size of the light entrance surface 33 of the inner lens 30. It is also preferable to arrange the light sources so that the spacing between them is narrow so that the light from each light source travels along the same optical path.

[0022] An inner lens 30 is disposed in front of the first light source 21A and the second light source 21B.

[0023] The inner lens 30 (an example of a light guide of the present disclosure) is a light guide that guides light from the first light source 21 A and the second light source 21 B. The inner lens 30 is made of a transparent resin such as acrylic or polycarbonate.

[0024] 4, the inner lens 30 includes a first plate-shaped light guide 31 including a light output surface 31a facing the light irradiation direction and a surface 31b opposite to the light output surface 31a on which a lens cut (not shown) for light extraction is formed, a second plate-shaped light guide 32 extending from one end edge (the upper end edge in FIG. 4) of the first plate-shaped light guide 31 toward the light source 20 and guiding the light emitted by the light source 20 to the one end edge of the first plate-shaped light guide 31, and a light entrance surface 33 provided at the end of the second plate-shaped light guide 32 facing the light source 20 and through which the light from the light source 20 enters. The light entrance surface 33 is aligned with the optical axis of the light source 20 (the optical axis of the first light source 21A). AX21A (and the optical axis of the second light source 21B AX21B )) and has a planar shape perpendicular to the plane.

[0025] As shown in FIG. 3, the second plate-shaped light guide 32 includes, in a top view, one side surface 32a disposed on the outer side in the vehicle width direction and the other side surface 32b disposed on the inner side in the vehicle width direction.

[0026] One side surface 32a includes a first side surface 32a1 disposed closer to the light incident surface 33 and a second side surface 32a2 disposed farther from the light incident surface 33.

[0027] The first side surface 32a1 is configured to prevent the light from the light source 20 entering through the light entrance surface 33 from being shifted in a direction parallel to the optical axis of the light source 20 (the optical axis of the first light source 21A) in a top view. AX21A (and the optical axis of the second light source 21B AX21B )) toward the other side surface 32b.

[0028] As shown in FIG. 3, first side surface 32a1 (first total reflection surface) extends from one side (outer side in the vehicle width direction) of light incident surface 33 toward the front of the vehicle and inward in the vehicle width direction, and is aligned with the optical axis of light source 20 (optical axis of first light source 21A) in a top view. AX21A (and the optical axis of the second light source 21B AX21B The second side surface 32a2 intersects with the optical axis of the light source 20 (the optical axis of the first light source 21A) from one side (the outer side in the vehicle width direction) of the light incident surface 33 in a top view so that the light from the light source 20 incident through the light incident surface 33 is guided within the second plate-shaped light guiding unit 32 directly to one end edge of the first plate-shaped light guiding unit 31 without being incident on the second side surface 32a2. AX21A (and the optical axis of the second light source 21B AX21B )) to one side (outside in the vehicle width direction) of one end edge of the first plate-shaped light guiding section 31.

[0029] On the other hand, the other side surface 32b is a second total reflection surface that totally reflects the totally reflected light from first total reflection surface 32a1 (see Ray2a and Ray2b in FIG. 5(b)) toward one edge of first plate-shaped light guide 31.

[0030] The other side surface 32b extends from the other side (inner side in the vehicle width direction) of the light incident surface 33 in a direction generally parallel to the first side surface 32a1 to the other side (inner side in the vehicle width direction) of one end edge of the first plate-shaped light guiding section 31.

[0031] In the vehicle lamp 10 configured as described above, a DRL lamp (or a position lamp) can be realized by turning on the first light source 21A that emits white light, while a turn lamp can be realized by turning on the second light source 21B that emits amber light.

[0032] The optical path of the light emitted by the first light source 21A and the optical path of the light emitted by the second light source 21B are the same. Hereinafter, the optical path of the light emitted by the first light source 21A will be described as a representative example.

[0033] 5(a) and 5(b) are top views of the vehicle lamp 10 with the optical path of the light emitted by the light source 20 drawn on them.

[0034] 5(a), when first light source 21A is turned on, light emitted by first light source 21A enters second plate-shaped light guiding unit 32 through light entrance surface 33. At this time, the light emitted by first light source 21A is slightly condensed by the action of light entrance surface 33, but still retains Lambertian characteristics after entering second plate-shaped light guiding unit 32.

[0035] As shown in FIG. 5(a), the light from the first light source 21A incident on the light incident surface 33 is incident on the optical axis AX of the first light source 21A in a top view. 21A In contrast, the relatively bright light Ray1a (light within a half-value angle of 60 degrees) on the other side (inner side in the vehicle width direction) does not enter one side surface 32a or the other side surface 32b, but travels directly toward one edge of the first plate-shaped light guide 31 as direct light, enters the first plate-shaped light guide 31 through the one edge of the first plate-shaped light guide 31, is guided within the first plate-shaped light guide 31, is totally reflected by a lens cut (not shown) formed on the surface 31b opposite the light output surface 31a, and exits from the light output surface 31a (mainly the rectangular area B1 in Figure 2(b)).

[0036] Similarly, the optical axis AX of the first light source 21A in top view 21A In contrast, the relatively dark light Ray1b (light with a half-value angle outside 60 degrees) on the other side (inner side in the vehicle width direction) does not enter one side surface 32a or the other side surface 32b, but instead travels as direct light directly toward one edge of the first plate-shaped light guide 31, enters the first plate-shaped light guide 31 through the one edge of the first plate-shaped light guide 31, is guided within the first plate-shaped light guide 31, is totally reflected by a lens cut (not shown) formed on the surface 31b opposite the light output surface 31a, and exits from the light output surface 31a (mainly the rectangular area B2 in Figure 2(b)).

[0037] On the other hand, the light from the first light source 21A incident on the light incident surface 33 is incident on the optical axis AX of the first light source 21A in a top view. 21A In contrast, the relatively bright light Ray2a (light within a half-value angle of 60 degrees) on one side (outside in the vehicle width direction) is totally reflected by one side surface 32a (first total reflection surface 32a1) and the other side surface 32b (second total reflection surface 32b) in that order, and then travels toward one end edge of the first plate-shaped light guide 31, enters the first plate-shaped light guide 31 through the one end edge of the first plate-shaped light guide 31, is guided within the first plate-shaped light guide 31, is totally reflected by a lens cut (not shown) formed on the surface 31b opposite the light output surface 31a, and exits from the light output surface 31a (rectangular area B2 in Figure 2(b)).

[0038] Similarly, the optical axis AX of the first light source 21A in top view 21A In contrast, the relatively dark light Ray2b (light with a half-value angle outside 60 degrees) on one side (outside in the vehicle width direction) is totally reflected by one side surface 32a (first total reflection surface 32a1) and the other side surface 32b (second total reflection surface 32b) in that order, and then travels toward one end edge of the first plate-shaped light guide 31, enters the first plate-shaped light guide 31 through the one end edge of the first plate-shaped light guide 31, is guided within the first plate-shaped light guide 31, is totally reflected by a lens cut (not shown) formed on the surface 31b opposite the light output surface 31a, and exits from the light output surface 31a (rectangular area B1 in Figure 2(b)).

[0039] As described above, the light rays Ray1a, Ray1b, Ray2a, and Ray2b emitted from the light emitting surface 31a function as a DRL lamp (or a position lamp). Also, the light rays Ray1a, Ray1b, Ray2a, and Ray2b emitted from the light emitting surface 31a provide uniform light emission from the inner lens 30 (first plate-shaped light guiding portion 31).

[0040] The conditions for uniformly (approximately uniformly) emitting light from the inner lens 30 (first plate-shaped light guiding section 31) vary depending on, for example, the shape, size, and thickness of the inner lens 30 (first plate-shaped light guiding section 31, etc.), the type and size of the light source 20, and the arrangement of the vehicle lamp components (for example, the inner lens 30 and the light source 20). For this reason, it is difficult to express the conditions for uniformly (approximately uniformly) emitting light from the surface of the inner lens 30 (first plate-shaped light guiding section 31) in specific numerical values.

[0041] However, by using a specified simulation software to change (adjust) at least one of the conditions for making the inner lens 30 (first plate-shaped light guiding section 31) emit light uniformly (approximately uniformly), and checking the light-emitting state of the inner lens 30 (first plate-shaped light guiding section 31) each time a change is made, it is possible to find the conditions for making the inner lens 30 (first plate-shaped light guiding section 31) emit light uniformly (approximately uniformly).

[0042] As described above, according to this embodiment, even if the light sources 20 (20A, 20B) with Lambertian light distribution arranged together in one place are used as the light source, the inner lens can be made to emit light uniformly (or approximately uniformly).

[0043] Next, a modified example will be described. FIG. 6 is a modified example (partially enlarged view) of the vehicle lamp 10. In FIG.

[0044] In the above embodiment, an example has been described in which first light source 21A and second light source 21B are arranged at an interval in the Z direction (thickness direction of second plate-shaped light guide 32), but this is not limiting. For example, first light source 21A and second light source 21B may be arranged at an interval in the Y direction (a direction intersecting (e.g., perpendicular to) the thickness direction of second plate-shaped light guide 32) as shown in Fig. 6 .

[0045] In the above embodiment, an example has been described in which two light sources (first light source 21A and second light source 21B) are used as the light sources arranged together in one place, but this is not limiting. For example, one or three or more light sources may be used as the light sources arranged together in one place.

[0046] In the above embodiment, an example has been described in which the vehicle lamp of the present disclosure is applied to a vehicle signal lamp that functions as a DRL lamp, a position lamp, or a turn lamp, but the present disclosure is not limited to this. The vehicle lamp of the present disclosure may also be applied to a vehicle signal lamp other than a DRL lamp, a position lamp, or a turn lamp, a vehicle headlamp, a general lighting device, etc.

[0047] All the numerical values ​​shown in the above embodiment are merely examples, and it goes without saying that other appropriate numerical values ​​can be used.

[0048] The above-described embodiments are merely examples in all respects. The present disclosure should not be construed as being limited by the description of the above-described embodiments. The present disclosure can be implemented in various other forms without departing from the spirit or main characteristics thereof. [Explanation of symbols]

[0049] 10...Vehicle lighting fixtures 20...Light source 21A…1st light source 21B…Second light source 22... Circuit board 30...Inner lens 31...First plate-shaped light guide section 31a…Idemitsu surface 31b…face 32...Second plate-shaped light guide section 32a...One side 32a1…First side (first total reflection surface) 32a2…Second side 32b...other side surface (second total reflection surface) 33...Light incident surface V...Vehicle

Claims

1. A light source and a light guide including a first plate-shaped light guide including a light output surface facing the light irradiation direction and a surface opposite to the light output surface on which lens cuts for light extraction are formed; a second plate-shaped light guide extending from one end edge of the first plate-shaped light guide toward the light source and guiding light emitted by the light source to the one end edge of the first plate-shaped light guide; and a light entrance surface provided at an end of the second plate-shaped light guide facing the light source, through which light from the light source enters; the second plate-shaped light guiding unit includes one side surface disposed on one side with respect to the optical axis of the light source and another side surface disposed on the other side with respect to the optical axis of the light source, the one side surface includes a first side surface disposed closer to the light incident surface and a second side surface disposed farther from the light incident surface, the first side surface is a first total reflection surface that totally reflects, toward the other side surface, relatively bright light on one side with respect to an optical axis of the light source among light from the light source that has entered through the light entrance surface, the other side surface is a second total reflection surface that totally reflects the light totally reflected from the first total reflection surface toward the one end edge of the first plate-shaped light guiding section, Among the light from the light source that enters through the light entrance surface, relatively bright light on one side with respect to the optical axis of the light source is totally reflected by the first total reflection surface and the second total reflection surface in this order, and then enters the first plate-shaped light guide part through the one end edge part of the first plate-shaped light guide part, is guided within the first plate-shaped light guide part, is totally reflected by the lens cut, and exits from the light exit surface, Of the light from the light source that enters through the light entrance surface, relatively bright light on the other side of the optical axis of the light source enters the first plate-shaped light guide as direct light through the one edge portion of the first plate-shaped light guide, is guided within the first plate-shaped light guide, is totally reflected by the lens cut, and exits from the light exit surface.

2. The vehicle lamp according to claim 1 , wherein the light source includes at least two light sources that are arranged in a thickness direction of the second plate-shaped light guide portion and emit light of different colors.

3. The vehicle lamp according to claim 1 , wherein the light source includes at least two light sources that are arranged in a direction intersecting a thickness direction of the second plate-shaped light guide portion and emit light of different colors.

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