Vehicle lamp

Abstract

To provide a lighting fixture for a vehicle capable of reducing a difference in luminance between a crossing part and a non-crossing part when an emission surface for emitting light irradiated from a light source through a reflection surface crosses.SOLUTION: And a lens 5a which is a light guide body having a secondary reflecting surface 33 for reflecting light incident from the light sources 3 and an emitting surface 35 for emitting the light reflected by the secondary reflecting surface 33. The lens 5a includes the first emitting surface which is the emitting surface 35 extending in the first direction and the second emitting surface which is the emitting surface 35 extending in the second direction intersecting the first direction, the first emitting surface and the second emitting surface have the intersection portion where the first emitting surface and the second emitting surface intersect each other, and the secondary reflecting surface 33 is configured such that the diffusion amount of the light in the first direction increases as the location where the light reaches the first emitting surface approaches the location where the light reaches the intersection portion.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, a vehicle lamp has been known that has a structure including a light guide, which is an optical element that reflects light emitted from a light source on a reflective surface and emits the reflected light from an emission surface (for example, Patent Document 1). This allows the vehicle lamp to emit light in various patterns according to the shape of the emission surface, thereby improving the design of the emitted light. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-21313 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the light guide in Patent Document 1 has an exit surface in the shape of a rectangular frame, and the corners of the frame are where two sides of the frame intersect. Therefore, the corners of the frame are where two exit surfaces corresponding to the two sides intersect. Therefore, at the corners of the frame, light is incident from the reflecting surfaces corresponding to the two exit surfaces, and the amount of incident light is increased at the corners of the frame compared to areas where the exit surfaces do not intersect, thereby increasing the brightness of the exit surface. As such, the vehicle lamp in Patent Document 1 may have a problem in that the brightness of the exit surface of the light guide differs between the corners and areas other than the corners, causing uneven brightness within the exit surface.

[0005] The present disclosure has been made to solve such conventional problems, and aims to provide a vehicle lamp that can reduce the difference in brightness between the intersecting and non-intersecting portions when the light emitted from the light source and the exit surface that emits the light via the reflective surface intersect. [Means for solving the problem]

[0006] The vehicle lamp according to the present disclosure is a vehicle lamp comprising a light source and a lens which is a light guide having a reflective surface which reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, wherein the lens comprises a first exit surface which is the exit surface extending in a first direction, and a second exit surface which is the exit surface extending in a second direction intersecting the first direction, the first exit surface and the second exit surface having an intersection where they intersect with each other, and the reflective surface is configured such that the amount of diffusion of light in the first direction increases as the point at which light is delivered to the first exit surface approaches the point at which light is delivered to the intersection.

[0007] Furthermore, a vehicle lamp according to the present disclosure is a vehicle lamp comprising a light source and a lens which is a light guide having a reflective surface which reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, wherein the lens comprises a first exit surface which is the exit surface extending in a first direction, and a second exit surface which is the exit surface extending in a second direction intersecting the first direction, wherein the first exit surface and the second exit surface have an intersection where they intersect with each other, and the reflective surface diffuses light more at a portion which delivers light to the intersection than at a portion which delivers light to a central portion of the exit surface in the extension direction, which is the direction in which the exit surface to which the light is delivered extends. [Effects of the Invention]

[0008] According to the present disclosure, a vehicle lighting fixture can be provided that can reduce the difference in brightness between the intersecting portion and the non-intersecting portion when the light emitted from the light source and the exit surface that emits the light via the reflective surface intersect. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1(a) is a perspective view showing a vehicle lamp according to a first embodiment of the present disclosure, and FIG. 1(b) is a view of FIG. 1(a) with the exterior removed. [Figure 2] FIG. 2 is a FF cross-sectional view (longitudinal cross-sectional view) of region A in FIG. [Figure 3]3 is an enlarged cross-sectional view of one of the lenses that make up the light frame of FIG. 2. FIG. [Figure 4] FIG. 3 is a perspective view of the light frame of FIG. 2. [Figure 5] FIG. 3 is a front view of the light frame of FIG. 2. [Figure 6] FIG. 3 is a rear view of the light frame of FIG. 2. [Figure 7] FIG. 7 is an enlarged cross-sectional view showing a part of a circular groove prism in the cross-sectional view taken along line GG in FIG. 6. [Figure 8] 10 is a rear view of the light frame and a close-up of the secondary reflecting surface in the rear view, showing the use of a compound lens instead of a circular groove prism. [Figure 9] FIG. 7 is an enlarged view of the lens in FIG. 6. [Figure 10] FIG. 3 is a top view of the lens of FIG. 2. [Figure 11] FIG. 3 is a partially enlarged view showing a first modified example of FIG. 2. [Figure 12] FIG. 3 is a partially enlarged view showing a second modified example of FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0010] Vehicle lighting devices according to embodiments of the present disclosure will be described below, but the present disclosure is not limited to the following embodiments and can be modified as appropriate without departing from the spirit of the present disclosure. Furthermore, in the embodiments, some configurations are omitted from illustration and description, but it goes without saying that publicly known or well-known technologies are applied as appropriate to the details of the omitted technologies within the scope of the content described below.

[0011] First, a schematic configuration of a vehicle lamp according to a first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1(a) is a perspective view showing a vehicle lamp according to a first embodiment of the present disclosure, and FIG. 1(b) is a view of FIG. 1(a) without an exterior. FIG. 2 is an FF cross-sectional view (longitudinal cross-sectional view) of region A in FIG. 1(b). FIG. 3 is an enlarged cross-sectional view of one of the lenses that make up the light frame of FIG. 2. FIG. 4 is a perspective view of the light frame of FIG. 2. The vehicle lamp 1 shown in FIG. 1 is a taillight of a vehicle, and includes an irradiation unit 21 and an exterior 25. The irradiation unit 21 is a part that irradiates light. The exterior 25 is a member that covers the periphery of the irradiation unit 21 to protect the irradiation unit 21.

[0012] As shown in FIG. 2 , the illumination unit 21 of the vehicle lamp 1 includes a light source 3 and a light frame 5. The illumination unit 21 of the vehicle lamp 1 also includes diffusion inner members 7a and 7b, shielding plates 9a and 9b, and a cover 11. The light source 3 is an illuminant that generates the light emitted by the vehicle lamp 1, such as an LED lamp. The light source 3 in FIG. 2 is mounted on a substrate 12 and emits light when power is supplied from a power source (not shown) via a wiring pattern (not shown) formed on the substrate 12. The light frame 5 is an optical element made of transparent resin or the like that has the function of emitting light incident from the light source 3 in a predetermined direction. The light frame 5 includes lenses 5a and 5b and a connecting surface 23. In the following description, the surface of the light frame 5 and the lenses 5a and 5b facing the light source 3, i.e., the surface onto which light from the light source 3 enters, is referred to as the back surface, and the surface opposite the back surface is referred to as the front surface. The surface connecting the front surface and the back surface is referred to as the side surface. The direction in which the lenses 5a and 5b are aligned is referred to as the up-down direction. For example, in FIG. 2, lens 5a is positioned above lens 5b.

[0013] Lenses 5a and 5b are light guides that emit light incident from light source 3 in a predetermined direction. As shown in FIG. 3, lens 5a has a U-shaped cross section and includes an incident surface 29, a primary reflecting surface 31, a secondary reflecting surface 33 (a reflecting surface), and an exit surface 35. Incident surface 29 is the portion where light from light source 3 enters. It is located on the back surface of lens 5a at a position corresponding to the bent end of the outer periphery of the U-shape and is a flat surface facing light source 3. Primary reflecting surface 31 reflects light incident on incident surface 29 toward the side surfaces of lenses 5a and 5b. It is the inner peripheral surface of a conical recess provided on the front surface of lens 5a at the bent end of the inner U-shape (see FIG. 4). Secondary reflecting surface 33 reflects light incident from light source 3 via primary reflecting surface 31 toward the front side, i.e., toward the end of the U-shape. The secondary reflective surface 33 is provided on the side of the lens 5a, specifically on the outer periphery of the U-shape, and is inclined at a predetermined inclination angle θ with respect to the incident surface 29. The secondary reflective surface 33 has a rectangular frame shape when viewed from the back of the lens 5a (see FIG. 6). The exit surface 35 is a surface from which light reflected by the secondary reflective surface 33 exits, and is located at the end of the U-shape. As shown in FIG. 4, the exit surface 35 has a rectangular frame shape when viewed from the front of the lens 5a. Note that while the lens 5b differs from the lens 5a in terms of size, shape, and installation position in the vehicular lamp 1, its configuration and function are similar to those of the lens 5a, and therefore its description will be omitted. As shown in FIG. 4, the connecting surface 23 is a light guide that connects the lenses 5a and 5b and is integrated with the lenses 5a and 5b. In FIG. 4, the connecting surface 23 connects the lower end of the lens 5a to the upper end of the lens 5b.

[0014] As described above, the light frame 5 has a configuration in which the lens 5a and the lens 5b (multiple lenses) are integrated with each other at the connecting surface 23. With this configuration, the number of components of the light frame 5 does not increase even if the number of lenses is increased, which is advantageous in terms of cost and productivity. Furthermore, since the connecting surface 23 is provided on the side surface of the lenses 5a and 5b, like the secondary reflective surface 33, providing the connecting surface 23 may result in partial chipping of the secondary reflective surface 33. However, in the light frame 5, the connecting surface 23 is also a light guide and transmits light. Therefore, even if the secondary reflective surface 33 is partially chipped due to the provision of the connecting surface 23, the light incident on the lenses 5a and 5b is not blocked by the connecting surface 23, and the design of the light emitted from the exit surface 35 is not impaired.

[0015] The diffusing inner lenses 7a and 7b shown in FIG. 2 are components that diffuse the light emitted from the light exit surface 35, thereby suppressing uneven brightness of the emitted light due to the shapes of the light exit surface 35 and the secondary reflection surface 33. The diffusing inner lenses 7a and 7b are disposed in front of the lenses 5a and 5b in the direction in which the lenses 5a and 5b emit light. Specifically, the diffusing inner lenses 7a and 7b can be configured to diffuse the emitted light by, for example, using a translucent resin colored milky white or the like. The shielding plates 9a and 9b are components that shield the light source 3 from view from the outside. They are opaque components disposed in front of the light source 3 and the lenses 5a and 5b in the direction in which the lenses 5a and 5b emit light. The cover 11 is a transparent member that covers and protects the diffusing inner lenses 7a and 7b and the shielding plates 9a and 9b.

[0016] In the vehicle lamp 1, light emitted from the light source 3 enters the lens 5a from the incident surface 29 and is reflected by the primary reflecting surface 31 toward the secondary reflecting surface 33, as shown by the arrow B in Figure 3. The light reflected by the primary reflecting surface 31 is reflected by the secondary reflecting surface 33 toward the exit surface 35, and is emitted to the outside from the exit surface 35. This completes the description of the general configuration of the vehicle lamp 1.

[0017] Next, the lens 5a of the vehicle lamp 1 will be described in detail with reference to FIGS. 4 to 12. FIG. 5 is a front view of the light frame 5 of FIG. 2. FIG. 6 is a rear view of the light frame 5 of FIG. 2. FIG. 7 is an enlarged cross-sectional view showing a part of the circular groove prism in the cross-sectional view taken along line G-G of FIG. 6. FIG. 8 is a rear view of the light frame 5 and an enlarged view of the secondary reflection surface in the rear view, showing a case where a compound lens is used instead of the circular groove prism. FIG. 9 is an enlarged view of the lens 5a of FIG. 6. FIG. 10 is a top view of the lens of FIG. 2. FIG. 11 is a partially enlarged view showing a first modified example of FIG. 2. FIG. 12 is a partially enlarged view showing a second modified example of FIG. 2.

[0018] As shown in FIG. 5, the exit surface 35 includes a first exit surface 35a and a second exit surface 35b. The first exit surface 35a extends in a first direction C1 and corresponds to two of the four sides of the frame that constitute the exit surface 35 that extend in the left-right direction. The second exit surface 35b extends in a second direction C2 that intersects with the first direction C1 and corresponds to two of the four sides of the frame that constitute the exit surface 35 that extend in the up-down direction. The first exit surface 35a and the second exit surface 35b have an intersection 35c where they intersect with each other. The intersection 35c is a portion that corresponds to a corner of the frame.

[0019] Furthermore, secondary reflecting surface 33 of lens 5a is configured so that the amount of diffusion of light in first direction C1 increases as the point at which light reaches first exit surface 35a approaches the point at which light reaches intersection 35c. Specifically, the point at which light reaches first exit surface 35a is, for example, a point on secondary reflecting surface 33 that is behind first exit surface 35a when the direction in which light emerges from first exit surface 35a is considered forward.

[0020] Here, "increasing the amount of light diffusion" means that the range of reflection angles of light reflected by the secondary reflective surface 33 becomes wider. Because light is incident on the intersection 35c from the points on the secondary reflective surface 33 that deliver light to the first and second exit surfaces 35a and 35b, if the amount of light diffusion on the secondary reflective surface 33 is the same regardless of location, the brightness at the intersection 35c is higher than at points other than the intersection 35c. On the other hand, in the secondary reflective surface 33 of the first embodiment, the amount of light diffusion increases as the light approaches the point where it reaches the intersection 35c, and light is emitted over a wider range, so some of the emitted light enters outside the range of the intersection 35c. Therefore, as the amount of light diffusion increases, the amount of light incident on the intersection 35c from the secondary reflective surface 33 decreases, resulting in a decrease in brightness. Therefore, in lens 5a, the increase in brightness at intersection 35c due to light being incident from two points on secondary reflective surface 33 is mitigated by a decrease in brightness due to an increase in the amount of light diffusion at the point of secondary reflective surface 33 that delivers the light to intersection 35c. Therefore, in the case where exit surfaces 35 that emit light irradiated from light source 3 via secondary reflective surface 33 intersect, lens 5a can reduce the difference in brightness between the intersecting portion and the non-intersecting portion. Therefore, vehicle lamp 1 can emit light incident from light source 3 with more uniform brightness.

[0021] As shown in FIG. 4, because the primary reflective surface 31 is conical, the areas of equal brightness reflected by the primary reflective surface 31 are distributed concentrically when viewed from the front or back of the lens 5a. On the other hand, the secondary reflective surface 33 is a rectangular frame-like area when viewed from the front or back of the lens 5a, not a circular area, so the brightness of light incident from the primary reflective surface 31 to the secondary reflective surface 33 varies depending on the location on the secondary reflective surface 33. Therefore, if the amount of light diffusion on the secondary reflective surface 33 is equal regardless of location, the distribution of brightness of light emitted from the secondary reflective surface 33 to the exit surface 35 also varies depending on the location. In this way, in the vehicle lamp 1, differences in the brightness of the emitted light occur due to differences in the shapes of the primary reflective surface 31 and the secondary reflective surface 33. However, by changing the amount of light diffusion on the secondary reflective surface 33, such brightness differences can be suppressed.

[0022] Additionally, the secondary reflective surface 33 of the lens 5a is preferably configured so that the amount of diffusion of light in the second direction C2 increases as the point at which light is delivered to the second exit surface 35b approaches the point at which light is delivered to the intersection 35c. In the following description, unless otherwise specified, the first embodiment will be described taking as an example a case where the amount of diffusion of light in the second direction C2 increases as the point at which light is delivered to the second exit surface 35b of the secondary reflective surface 33 approaches the point at which light is delivered to the intersection 35c.

[0023] As shown in FIG. 6 , the secondary reflection surface 33 has circular groove prisms 41 as a specific structure for diffusing light. As shown in FIGS. 6 and 7 , the circular groove prisms 41 are circular grooves extending in a cross direction that intersects with the extension direction of the light exit surface 35 to which the light is directed, and multiple circular groove prisms 41 are arranged in the extension direction. When the light destination of the circular groove prisms 41 is the first light exit surface 35a, the circular groove prisms 41 that direct light to the first light exit surface 35a are provided in region R1 in FIG. 6 . Region R1 is the region behind the first light exit surface 35a. The circular groove prisms 41 provided in region R1 extend in a cross direction that intersects with direction C1, the extension direction of the first light exit surface 35a. For example, the direction E in which the circular groove prisms 41c provided in region R1 shown in FIG. 6 extend intersects with direction C1. Furthermore, a plurality of circular groove prisms 41 provided in region R1 are arranged in the direction C1, which is the extending direction of first exit surface 35a.

[0024] Furthermore, the multiple circular groove prisms 41 shown in FIG. 6 may have a constant groove width WP, as shown in FIG. 7. However, the deeper the groove depth DP of the circular groove prism 41, the greater the amount of light diffusion. Therefore, the groove depth DP of the circular groove prism 41 increases as the circular groove prism 41 approaches the intersection 35c. With this configuration, when light is reflected by the secondary reflection surface 33, the amount of light diffusion is greater at the intersection 35c than at the non-intersection. Therefore, simply increasing the groove depth DP of the circular groove prism 41a as the circular groove prism 41 approaches the intersection 35c can reduce the difference in brightness between the intersection and non-intersection portions of the exit surface 35. Note that the deeper the groove depth DP, the greater the amount of light diffusion. On the other hand, the deeper the groove depth DP, the more light is concentrated at the bottom of the circular groove prism 41, resulting in a noticeable stripe pattern in the emitted light due to the difference in brightness between the light-concentrated area and its surroundings. Therefore, it is preferable to select the groove depth DP appropriately within a range that can suppress the occurrence of stripes in the reflected light while reducing the difference in brightness between the intersecting and non-intersecting portions of the exit surface 35. Furthermore, the groove depth DP of the circular groove prism 41 may vary depending on the position in the direction in which the groove extends.

[0025] However, the structure for diffusing light at the secondary reflecting surface 33 is not limited to the circular groove prism 41. For example, the amount of light diffusion at the secondary reflecting surface 33 can be increased by changing the inclination angle θ of the secondary reflecting surface 33 relative to the incident surface 29 depending on the location, as shown in FIG. 3 . That is, to increase the amount of light diffusion at the secondary reflecting surface 33, an inclined surface 65 whose inclination angle θ relative to the incident surface 29 is changed depending on the amount of light diffusion may be used. Note that because FIG. 3 is a cross-sectional view, the inclination angle θ is shown only in the direction parallel to the cross section, but it may also be inclined in the direction perpendicular to the cross section. A structure for increasing the amount of light diffusion at the secondary reflecting surface 33 may also be a compound lens 63 in which hemispherical recesses 61 are arranged in a lattice pattern on the secondary reflecting surface 33, as shown in FIG. 8.

[0026] The structure for diffusing light on the secondary reflection surface 33—whether the circular groove prism 41, the inclined surface 65, or the compound lens 63—can be selected appropriately, taking into consideration the advantages of each. For example, the circular groove prism 41 is advantageous in that the amount of light diffusion can be adjusted simply by changing the groove depth DP. The circular groove prism 41 is also advantageous in that the grooves extend in only one direction, making it less likely for the reflected light to have uneven brightness due to the groove shape. The compound lens 63 is also advantageous in that the reflected light is diffused in two directions, vertically and horizontally, of the grating, allowing for fine adjustment of the amount of diffusion. In the following description, unless otherwise specified, the first embodiment will be described using the structure using the circular groove prism 41 as an example of the structure for diffusing light on the secondary reflection surface 33.

[0027] The circular groove prism 41 has a groove depth DP that increases as the distance from the intersection 35c increases. However, the groove depth DP does not necessarily have to increase as the distance from the intersection 35c increases. For example, as shown in FIG. 6, the circular groove prism 41a that delivers light to the intersection 35c in FIG. 5 may have a deeper groove depth DP than the circular groove prism 41b that delivers light to the central portion 43c (see FIG. 5) of the light exiting surface 35 in the C1 direction. In this configuration, when light is reflected by the secondary reflection surface 33, the circular groove prism 41a located in the portion that delivers light to the intersection 35c reflects the incident light so that the light is more diffused than the circular groove prism 41b located in the portion that delivers light to the central portion 43c where the light exiting surface 35 does not intersect. Therefore, the amount of light diffused upon reflection is greater at the intersection 35c than at the central portion 43c. In this configuration, the difference in brightness between the intersection and non-intersection portions of the light exit surface 35 can be reduced simply by making the groove depth DP of the circular groove prism 41a that delivers light to the intersection 35c deeper than the groove depth DP of the circular groove prism 41b that delivers light to the center portion 43c. In this way, the secondary reflection surface 33 may be configured so that the amount of light diffusion is greater at the portion that delivers light to the intersection 35c than at the portion that delivers light to the center portion 43c. Also, in this configuration, it is not necessarily necessary to configure the groove depth DP to deepen as the distance to the portion that delivers light to the intersection 35c increases.

[0028] Alternatively, the secondary reflecting surface 33 may be configured such that only some of the circular groove prisms 41 have a gradually increasing groove depth DP as they approach the intersection 35c. For example, the secondary reflecting surface 33 shown in FIG. 9 has three regions, a central region 45a, an intersection region 45b, and a transition region 45c, which are depicted with different hatching patterns. The central region 45a includes the region where light is delivered to the central region 43c, and is a region where the desired light can be uniformly reflected even if the circular groove prisms 41 have a uniform groove depth DP. Within the central region 45a, the circular groove prisms 41 have a uniform groove depth DP. The intersection region 45b includes the region where light is delivered to the intersection 35c. Within the intersection region 45b, the circular groove prisms 41 have a uniform groove depth DP. The transition region 45c is a region between the central region 45a and the intersection region 45b. In the secondary reflecting surface 33, the groove depth DP of the circular groove prism 41 is deeper in the intersection region 45b than in the central region 45a. Furthermore, in the transition region 45c of the secondary reflecting surface 33, the groove depth DP of the circular groove prism 41 becomes deeper as it approaches the intersection region 45b. In this manner, only the transition region 45c may be configured so that the groove depth DP gradually deepens as it approaches the point where light reaches the intersection 35c. In this configuration, the secondary reflecting surface 33 has the least amount of light diffusion in the central region 45a and the most amount of light diffusion in the intersection region 45b, and the amount of light diffusion gradually increases in the transition region 45c from the central region 45a toward the intersection region 45b. In this configuration, the groove depth DP of the circular groove prism 41 can be gradually changed only in the region where a gradual change in the amount of light diffusion is required.

[0029] The lengths of the circular groove prisms 41 in the crossing direction do not need to be uniform, and it is preferable that the lengths in the crossing direction increase as the distance to the intersection 35c increases. For example, in the circular groove prism 41 shown in Figure 10, the length L1 of the circular groove prism 41a that reflects light to the intersection 35c (see Figure 5) is longer than the length L2 of the circular groove prism 41b that reflects light to the center 43c (see Figure 5). Furthermore, the length of the circular groove prism 41 gradually increases from the circular groove prism 41b toward the circular groove prism 41a. In this configuration, the range over which the secondary reflection surface 33 diffuses light in the crossing direction increases as the secondary reflection surface 33 approaches the intersection 35c where the light is delivered to the intersection 35c where the exit surface 35 (see Figure 3) intersects. 5, the width Wa of the intersection 35c of the exit surface 35 is wider than the width Wb of the portion of the first exit surface 35a that does not intersect with the second exit surface 35b and the width Wc of the portion of the second exit surface 35b that does not intersect with the first exit surface 35a. Therefore, in the secondary reflecting surface 33, the circular groove prism 41 is made longer as it approaches the portion that delivers light to the intersection 35c, thereby widening the range over which light is diffused in the intersection direction. This allows the secondary reflecting surface 33 to deliver light to the entire width of the exit surface 35. Therefore, even when the width Wa of the intersection 35c is wider than the widths Wb and Wec of the non-intersecting portions, the lens 5a can prevent a decrease in brightness at the edge of the intersection 35c on the exit surface 35.

[0030] As described above, the lens 5a has a secondary reflection surface 33 with a light-diffusing structure, such as the circular groove prism 41. The exit surface 35 may also have a light-diffusing structure. Specifically, the amount of light diffusion in the width direction of the exit surface 35 increases as the width W (see FIG. 2) of the diffusing inner liner 7a increases in a direction intersecting the extension direction of the exit surface 35 (direction C1 or C2 in FIG. 5). For example, consider a case where the width W2 shown in FIG. 11(b) is greater than the width W1 shown in FIG. 11(a) at two locations on the lens 5a shown in FIGS. 11(a) and 11(b), and the distance D between the exit surface 35 and the diffusing inner liner 7a remains the same between FIGS. 11(a) and 11(b). Note that the widths W1 and W2 are the widths of the diffusing inner liner 7a, more specifically, the widths of the flat portion of the diffusing inner liner 7a in front of the exit surface 35. In this case, the maximum diffusion angle α2 at which light exiting from the exit surface 35 is diffused, as shown in FIG. 11(b), is greater than the maximum diffusion angle α1 at which light exiting from the exit surface 35 is diffused, as shown in FIG. 11(a). Both maximum diffusion angles α1 and α2 are angles at which light is emitted across the entire width of the diffusing inner layer 7a. In this manner, the amount of light diffusion across the width of the exit surface 35 may vary depending on the width W of the diffusing inner layer 7a. With this configuration, even if the width W of the diffusing inner layer 7a varies depending on the position of the exit surface 35, light can be emitted across the entire width of the diffusing inner layer 7a.

[0031] Furthermore, the amount of diffusion in the width direction of the exit surface 35 of the lens 5a may decrease as the distance D from the diffusing inner 7a shown in FIG. 2 increases, and the amount of diffusion in the width direction may increase as the distance D from the diffusing inner 7a decreases. For example, consider a case where, at two locations on the lens 5a shown in FIGS. 12(a) and 12(b), the distance D2 shown in FIG. 12(b) is closer than the distance D1 shown in FIG. 12(a), and the width W of the diffusing inner 7a remains the same between FIGS. 12(a) and 12(b). Note that the distances D1 and D2 are the distances between the exit surface 35 and the diffusing inner 7a, more specifically, the distance between the flat portion in front of the exit surface 35 and the exit surface 35 of the diffusing inner 7a. In this case, the maximum diffusion angle β2 at which light is diffused from the exit surface 35 shown in FIG. 12(b) is greater than the maximum diffusion angle β1 of light emitted from the exit surface 35 shown in FIG. 12(a). Furthermore, the maximum diffusion angles β1 and β2 are both angles at which light is emitted across the entire width of the diffusing inner layer 7a. Thus, the amount of light diffusion across the width of the exit surface 35 may vary depending on the distance D from the diffusing inner layer 7a. With this configuration, even if the distance D from the exit surface 35 varies depending on the position of the exit surface 35, light can be emitted across the entire width of the diffusing inner layer 7a. For example, in the vehicle lamp 1 shown in FIG. 2, due to design constraints of the vehicle on which it is installed, the diffusing inner layer 7a is tilted downward so that the distance D from the exit surface 35 increases. In this case, although the distance D between the exit surface 35 and the diffusing inner layer 7a varies depending on the location, the amount of diffusion across the width of the exit surface 35 decreases as the distance D from the diffusing inner layer 7a increases, allowing light to be emitted across the entire width of the diffusing inner layer 7a. The exit surface 35 may be configured such that the amount of light diffusion in the width direction increases as the widths W1, W2 (see Figure 11) of the diffusion inner 7a increase, and the amount of light diffusion in the width direction increases as the distances D1, D2 to the diffusion inner 7a decrease.

[0032] The structure for diffusing light on the exit surface 35 is not particularly limited, but examples include structures similar to those for diffusing light on the secondary reflection surface 33. For example, FIGS. 4 and 5 illustrate a structure in which the exit surface 35 has a circular groove prism 51 extending in the extension direction (directions C1 and C2 in FIG. 5). Since the exit surface 35 shown in FIGS. 4 and 5 has a frame shape when viewed from the front of the lens 5a, the circular groove prism 51 has a frame-shaped groove when viewed from the front of the lens 5a. Furthermore, since the amount of light diffusion required of the circular groove prism 51 varies depending on the location, the groove depth DP of the circular groove prism 51 also varies depending on the location. However, the structure for diffusing light on the exit surface 35 is not limited to the circular groove prism 51, and may have a structure similar to the inclined surface 65 (see FIG. 3) or the compound lens 63 in FIG. 8. As with the secondary reflection surface 33, which of these structures is to be adopted may be selected appropriately in consideration of the advantages of each.

[0033] The exit surface 35 may also be textured. In this structure, the light emitted from the exit surface 35 is diffused by the texture. Therefore, the texture can reduce brightness variations in the light emitted from the exit surface 35, which are caused by the shape of the secondary reflecting surface 33. For example, if the secondary reflecting surface 33 has a circular groove prism 41, the light emitted from the exit surface 35 will have a light and dark stripe pattern corresponding to the groove shape of the circular groove prism 41. However, by textured the exit surface 35, the stripe pattern can be made less visible. Note that the deeper the texture, the greater the amount of light diffusion and the smaller the brightness variations. However, the deeper the texture, the lower the brightness and the lower the light distribution performance. Therefore, the depth of the texture can be appropriately set based on the balance between the required amount of light diffusion and the desired light distribution performance. This concludes the detailed description of the lens 5a of the vehicle lamp 1.

[0034] As described above, according to the first embodiment, the vehicle lamp 1 includes a light source 3 and lenses 5a and 5b. The lens 5a includes a secondary reflective surface 33, a first exit surface 35a, and a second exit surface 35b. The first exit surface 35a and the second exit surface 35b intersect at an intersection 35c. The secondary reflective surface 33 is configured so that the amount of light diffusion in the first direction C1 increases as the point at which light reaches the first exit surface 35a approaches the point at which light reaches the intersection 35c. With this configuration, the increase in luminance at the intersection 35c due to light incident from two points on the secondary reflective surface 33 is mitigated by the decrease in luminance due to the increased amount of light diffusion at the point on the secondary reflective surface 33 that reaches the intersection 35c. Therefore, when the exit surfaces 35 that emit light irradiated from the light source 3 via the secondary reflective surface 33 intersect, the difference in luminance between the intersection and non-intersection can be reduced.

[0035] Furthermore, according to the first embodiment, the secondary reflecting surface 33 has a circular groove prism 41, and the groove depth DP of the circular groove prism 41 increases as the distance to the intersection 35c increases. With this configuration, when light is reflected by the secondary reflecting surface 33, it is reflected so as to spread in the width direction of the circular groove prism 41, but is reflected so as to spread even more widely at the intersection with the exit surface 35. With this configuration, simply by increasing the groove depth DP of the circular groove prism 41a as the distance to the intersection 35c decreases, it is possible to reduce the difference in brightness between the intersection and non-intersection of the exit surface 35.

[0036] Furthermore, according to the first embodiment, the secondary reflecting surface 33 has a circular groove prism 41a that delivers light to the intersection 35c with a deeper groove depth DP than the circular groove prism 41b that delivers light to the central portion 43c. With this configuration, when light is reflected by the secondary reflecting surface 33, the circular groove prism 41a provided in the portion that delivers light to the intersection 35c reflects the incident light so that the light is more spread out than the circular groove prism 41b provided in the portion that delivers light to the central portion 43c where the exit surface 35 does not intersect. Therefore, simply by making the groove depth DP of the circular groove prism 41a that delivers light to the intersection 35c deeper than the groove depth DP of the circular groove prism 41b that delivers light to the central portion 43c, the difference in brightness between the intersecting and non-intersecting portions of the exit surface 35 can be reduced.

[0037] On the other hand, according to the first embodiment, the secondary reflective surface 33 has a central region 45a, an intersection region 45b, and a transition region 45c. The groove depth DP of the circular groove prism 41 is deeper in the intersection region 45b of the secondary reflective surface 33 than in the central region 45a, and the groove depth DP of the circular groove prism 41 becomes deeper in the transition region 45c as it approaches the intersection region 45b. With this configuration, the secondary reflective surface 33 has the least amount of light diffusion in the central region 45a, the most amount of light diffusion in the intersection region 45b, and the amount of light diffusion gradually increases in the transition region 45c from the central region 45a toward the intersection region 45b. Therefore, the groove depth DP of the circular groove prism 41 can be gradually changed only in the region where the amount of light diffusion needs to be gradually changed.

[0038] Furthermore, according to the first embodiment, the length of the circular groove prism 41 in the intersecting direction increases as it approaches the point where light is reflected at the intersection 35c. With this configuration, the range over which light is diffused in the intersecting direction increases as it approaches the intersection of the light exit surface 35. Therefore, even if the width Wa at the intersection 35c is wider than the widths Wb and Wc of the non-intersecting portions, it is possible to prevent a decrease in brightness at the edge of the light exit surface 35 at the intersection 35c.

[0039] Furthermore, according to the first embodiment, the amount of light diffusion in the width direction at the exit surface 35 increases as the width W of the diffusing inner member 7a increases. In this configuration, the amount of light diffusion in the width direction varies depending on the width W of the diffusing inner member 7a. Therefore, even if the width W of the diffusing inner member 7a varies depending on the position of the exit surface 35, light can be emitted to the edge of the diffusing inner member 7a.

[0040] On the other hand, according to the first embodiment, the amount of diffusion in the width direction of the light exit surface 35 increases as the distance D between the light exit surface 35 and the diffusing inner member 7a decreases. In this configuration, the amount of diffusion in the width direction varies depending on the distance D between the light exit surface 35 and the diffusing inner member 7a. Therefore, even if the distance D between the light exit surface 35 and the diffusing inner member 7a varies depending on the position of the light exit surface 35, light can be emitted to the edge of the diffusing inner member 7a.

[0041] Furthermore, according to the first embodiment, the exit surface 35 has either a circular groove prism 51, an inclined surface 65, or a compound lens 63. In this configuration, the amount of diffusion changes as light is bent by the circular groove prism 41 or the inclined surface 65 of the exit surface 35. Therefore, when the exit surface 35 has a circular groove prism 51, the amount of diffusion of light can be adjusted simply by changing the width and depth (curvature) of the groove. Furthermore, when the exit surface 35 has a circular groove prism 51, the groove extends in only one direction, so brightness unevenness in the reflected light due to the groove shape is unlikely to occur. On the other hand, when the exit surface 35 has an inclined surface 65, there are no irregularities within the exit surface, so brightness unevenness in the reflected light due to irregularities does not occur. Furthermore, when the exit surface 35 has a compound lens 63, the reflected light is diffused in two directions, allowing for fine adjustment of the amount of diffusion.

[0042] Furthermore, according to the first embodiment, the exit surface 35 is a textured surface. In this configuration, the texture diffuses the light exiting from the exit surface 35. Therefore, the texture can reduce unevenness in brightness caused by the shape of the secondary reflection surface 33.

[0043] On the other hand, according to the first embodiment, the vehicle lamp 1 includes lenses 5a and 5b and a light frame 5 having a connecting surface 23. In this configuration, the lenses 5a and 5b are integrated at the connecting surface 23. Therefore, even if the number of lenses increases, the number of parts of the light frame 5 does not increase, which is advantageous in terms of cost and productivity. Furthermore, in this configuration, the connecting surface 23 is also a light guide and transmits light. Therefore, by providing the connecting surface 23, even if the secondary reflection surface 33 is partially chipped, the light is not blocked by the connecting surface 23, and the design of the light emitted from the emission surface 35 is not impaired.

[0044] Next, a second embodiment will be described with reference to Figures 3, 11, and 12. The second embodiment is different from the first embodiment in that it is essential that the light exit surface 35 has a structure that diffuses light, but it is not essential that the secondary reflection surface 33 has a structure that diffuses light.

[0045] The vehicle lamp 1 according to the second embodiment is similar to the first embodiment except that the light emitting surface 35 must have a structure that diffuses light, but the secondary reflecting surface 33 does not necessarily have a structure that diffuses light. Specifically, as shown in Fig. 3, the lens 5a of the vehicle lamp 1 according to the second embodiment has a light source 3, a secondary reflecting surface 33 that reflects light incident from the light source 3, and an exit surface 35 from which the light reflected by the secondary reflecting surface 33 exits. Furthermore, the exit surface 35 of the lens 5a may be configured so that the amount of light diffusion in the width direction increases as the widths W1 and W2 of the diffusing inner 7a become wider, as shown in Fig. 11.

[0046] 12, the amount of diffusion in the width direction of the light exit surface 35 may decrease as the distances D1, D2 from the diffusing inner layer 7a increase, or the amount of diffusion in the width direction may increase as the distances D1, D2 from the diffusing inner layer 7a decrease. Note that the amount of diffusion in the width direction of the light exit surface 35 may increase as the widths W1, W2 of the diffusing inner layer 7a increase, and may also increase as the distances D1, D2 from the diffusing inner layer 7a decrease.

[0047] The structure of the exit surface 35 for diffusing light may be the same as that of the first embodiment. Specifically, the exit surface 35 may have a circular groove prism 51, may have a configuration similar to the inclined surface 65, or may have a configuration similar to the compound lens 63.

[0048] In the second embodiment, the secondary reflecting surface 33 may or may not have a structure for diffusing light, such as the circular groove prism 41, as in the first embodiment.

[0049] The vehicle lamp 1 according to the second embodiment can also be described as follows. [Appendix (1)] A vehicle lamp including a light source and a lens that is a light guide having a reflective surface that reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, The exit surface of the lens is The diffusion inner is disposed in front of the lens in the direction in which the lens emits light, and diffuses and emits light. As the width of the diffusion inner increases in the direction intersecting the extension direction, which is the direction in which the emission surface extends, the amount of light diffusion in the width direction increases. A vehicle lamp characterized by: [Appendix (2)] The exit surface is The closer the distance to the diffusing inner, the greater the amount of light diffusion in the width direction. The vehicle lamp according to (1), characterized in that: [Appendix (3)] The light exit surface has either a circular groove prism extending in the extension direction, an inclined surface whose inclination angle with respect to the incident surface onto which light from the light source is incident is changed according to the amount of diffusion of the light, or a compound lens in which hemispherical recesses are arranged in a lattice pattern. The vehicle lamp according to (1) or (2), characterized in that: [Appendix (4)] A vehicle lamp including a light source and a lens that is a light guide having a reflective surface that reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, The exit surface of the lens is The lens is disposed in front of the lens in the direction in which the light is emitted, and the closer the distance to the diffusion inner that diffuses and emits the light, the greater the amount of diffusion in the width direction, which is the direction that intersects with the extension direction, which is the direction in which the emission surface extends. A vehicle lamp characterized by:

[0050] The present disclosure has been described above based on the embodiments, but the present disclosure is not limited to the above embodiments, and modifications may be made or publicly known or well-known technologies may be combined within the scope of the present disclosure.

[0051] For example, in the above embodiment, the diffusion inner 7a is made of a translucent resin colored milky white, but the diffusion inner 7a is not limited to a colored translucent resin as long as it has a structure that can diffuse light. For example, the diffusion inner 7a may have a textured surface, or may have a circular groove prism or a compound lens on its surface, similar to the secondary reflection surface 33 and the exit surface 35. [Explanation of symbols]

[0052] 1: Vehicle lighting fixtures 3:Light source 5: Light frame 5a, 5b: Lens 7a, 7b: Diffusion inner 23: Connecting surface 29:Incidence plane 33: Secondary reflective surface (reflective surface) 35: Exit surface 35a: First exit surface 35b: second exit surface 35c: Intersection 41, 41a, 41b, 41c: circular groove prism 43c: Central part 45a: Central area 45b: Intersection area 45c: Transition area 51: Circular groove prism 61: Recess 63: Compound eye lens 65: Inclined surface C1: First direction C2: Second direction D, D1, D2: distance DP: Groove depth L1, L2: Length W: Width θ: Inclination angle

Claims

1. A vehicle lamp including a light source and a lens that is a light guide having a reflective surface that reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, The lens is a first light exit surface that is the light exit surface extending in a first direction; a second light exit surface that is the light exit surface extending in a second direction intersecting the first direction; Equipped with the first exit surface and the second exit surface have an intersection portion where they intersect with each other, The reflecting surface is configured such that the amount of diffusion of light in the first direction increases as the portion that delivers light to the first emission surface approaches the portion that delivers light to the intersection. A vehicle lamp characterized by:

2. The reflective surface is a circular groove extending in a cross direction that is a direction intersecting with an extension direction that is a direction in which the exit surface to which light is delivered extends, and a plurality of circular groove prisms arranged in the extension direction; The groove depth of the circular groove prism becomes deeper as it approaches the point where light is delivered to the intersection.

2. A vehicle lamp according to claim 1, wherein:

3. A vehicle lamp including a light source and a lens that is a light guide having a reflective surface that reflects light incident from the light source and an exit surface from which the light reflected by the reflective surface exits, The lens is a first light exit surface that is the light exit surface extending in a first direction; a second light exit surface that is the light exit surface extending in a second direction intersecting the first direction; Equipped with the first exit surface and the second exit surface have an intersection portion where they intersect with each other, The reflective surface is The amount of light diffused at a portion where light is delivered to the intersection is greater than the amount of light diffused at a portion where light is delivered to a central portion of the exit surface in the extension direction, which is the direction in which the exit surface to which light is delivered extends. A vehicle lamp characterized by:

4. The reflective surface is a central region that is a region including a portion that delivers light to a central portion of the light exit surface in the extension direction; An intersection region that is a region including a portion where light is delivered to the intersection; a transition region between the central region and the intersection region; and The groove depth of the circular groove prism is deeper in the intersection region than in the central region, and the groove depth of the circular groove prism in the transition region becomes deeper as it approaches the intersection region.

3. A vehicle lamp according to claim 2.

5. The circular groove prism has a length in the crossing direction that increases as it approaches the point where the light is delivered to the crossing portion.

5. A vehicle lamp according to claim 2 or 4.

6. The exit surface is The diffusion inner is disposed in front of the lens in the direction in which the lens emits light, and diffuses and emits light. As the width of the diffusion inner increases in the direction intersecting the extension direction, which is the direction in which the emission surface extends, the amount of light diffusion in the width direction increases.

2. A vehicle lamp according to claim 1, wherein:

7. The exit surface is The lens is disposed in front of the lens in the direction in which the light is emitted, and the closer the distance to the diffusion inner that diffuses and emits the light, the greater the amount of diffusion in the width direction, which is the direction that intersects with the extension direction, which is the direction in which the emission surface extends.

2. A vehicle lamp according to claim 1, wherein:

8. The light exit surface has either a circular groove prism extending in the extension direction, an inclined surface whose inclination angle with respect to the incident surface onto which light from the light source is incident is changed according to the amount of diffusion of the light, or a compound lens in which hemispherical recesses are arranged in a lattice pattern.

8. A vehicle lamp according to claim 6 or 7.

9. The light exit surface is a textured surface.

5. A vehicle lamp according to claim 1, wherein the light source comprises a first light source.

10. A light frame having a plurality of the lenses and a connecting surface which is a light guide that is integrated with the plurality of lenses and connects the plurality of lenses is provided.

5. A vehicle lamp according to claim 1, wherein the light source comprises a first light source.

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