Vehicle lighting fixtures

Abstract

To provide a vehicular lightning device which carries out accurate light distribution control while securing a sufficient light volume of an outgoing beam from an outer peripheral edge part of a lens.SOLUTION: A lens 30 is configured such that a back surface 34b of a peripheral region 34 positioned around a central region 32 of the lens is sectioned into an inner peripheral side region 34b1 and an outer peripheral side region 34b2. Further, the inner peripheral side region 34b1 is configured such that a plurality of total reflection prism elements 34s1 is formed with an enveloping surface formed by a plurality of first annular concave curve surfaces C1, and the outer peripheral side region 34b2 is configured such that a plurality of total reflection prism elements 34s2 is formed with an enveloping surface formed by a plurality of second annular concave curve surfaces C2. Whereby, an outgoing beam from a light emitter 22 can be used as front irradiation light having approximately even brightness over a wide range. Additionally, in an outer peripheral edge part of the outer peripheral side region 34b2, a cross-sectional shape of the total reflection prism element 34s2 is not made extremely large, which increases formability of the lens 30, thereby improving accuracy of light distribution.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a vehicle lamp configured to irradiate light emitted from a light source forward through a lens. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a vehicle lamp is known that is configured to irradiate light emitted from a light source toward the front of the lamp via a lens.

[0003] Patent Document 1 describes a lens configuration for such a vehicle lamp, which has a central region centered on an optical axis extending in the fore-and-aft direction of the lamp, and a peripheral region located around the central region, with multiple total reflection prism elements formed on the rear surface of the peripheral region in a concentric arrangement centered on the optical axis. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-187859 Summary of the Invention [Problem to be solved by the invention]

[0005] By adopting a configuration in which light emitted from a light source is incident on multiple total reflection prism elements and then totally reflected toward the front of the lamp, as in the lens of the vehicle lamp described in the above-mentioned Patent Document 1, it is possible to use the light emitted from the light source as forward illumination light over a wide range.

[0006] However, in the vehicle lamp shown in Figure 1 of Patent Document 1, the lens is formed so as to extend in a flat plate shape along a vertical plane perpendicular to the optical axis, and therefore, in many cases, a sufficient amount of light is not obtained from the light source that is directed toward the outer peripheral edge of the lens, and therefore it is not easy to ensure a sufficient amount of light emitted from the outer peripheral edge of the lens.

[0007] On the other hand, if the lens is configured to extend and curve toward the rear of the lamp relative to a vertical plane perpendicular to the optical axis, as in the vehicle lamp shown in Figure 11 of Patent Document 1, it is possible to obtain a sufficient amount of light even with respect to the light emitted from the light source toward the outer peripheral edge of the lens.

[0008] However, when such a lens is used, the total internal reflection prism elements formed on the outer periphery of the lens inevitably become large in size, resulting in a large change in thickness at the outer periphery of the lens, which makes it difficult to precisely form the total internal reflection prism elements at the outer periphery when molding the lens, and therefore makes it difficult to precisely control the light distribution by the lens.

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a vehicle lamp that is configured to irradiate light emitted from a light source toward the front of the lamp through a lens, and that can ensure a sufficient amount of light emitted from the outer peripheral edge of the lens while allowing the lens to accurately control the light distribution. [Means for solving the problem]

[0010] The present invention is intended to achieve the above object by devising a configuration for the rear surface in the peripheral region of the lens.

[0011] That is, the vehicle lamp according to the present invention is A vehicle lamp including a light source and a lens, and configured to irradiate light emitted from the light source toward a front of the lamp through the lens, The lens has a central region centered on an optical axis extending in a front-to-rear direction of the lamp, and a peripheral region located around the central region, a plurality of total reflection prism elements that cause the incident light from the light source to be totally reflected toward the front of the lamp are formed on the rear surface of the peripheral area in a state of being arranged concentrically around the optical axis, The rear surface of the peripheral region is divided into an inner peripheral region and an outer peripheral region, The plurality of total reflection prism elements are characterized in that in the inner peripheral region, a first annular concave curved surface centered on the optical axis is formed as an envelope surface, and in the outer peripheral region, a second annular concave curved surface centered on the optical axis is formed as an envelope surface.

[0012] The type of the "vehicle lamp" is not particularly limited, and for example, a head lamp, a fog lamp, a tail lamp, a clearance lamp, etc. can be used.

[0013] The type of the "light source" is not particularly limited, and for example, a light emitting element such as a light emitting diode, a light source bulb, or the like can be used.

[0014] The specific range and outer shape of each of the "central region" and "peripheral region" are not particularly limited.

[0015] The specific curvature of each of the "first annular concave curved surface" and the "second annular concave curved surface" is not particularly limited. [Effects of the Invention]

[0016] The vehicle lamp of the present invention is configured to irradiate light emitted from a light source toward the front of the lamp through a lens, and on the rear surface of the peripheral region of the lens located around a central region centered on an optical axis extending in the fore-and-aft direction of the lamp, a plurality of total reflection prism elements are formed, arranged concentrically around the optical axis, which allow the light emitted from the light source to be totally reflected toward the front of the lamp after it is incident thereon, so that the light emitted from the light source can be used as forward illumination light over a wide range.

[0017] Furthermore, the rear surface of the peripheral region of the lens is divided into an inner region and an outer region, and the multiple total reflection prism elements are formed in the inner region with a first annular concave curved surface centered on the optical axis as an envelope surface, and in the outer region with a second annular concave curved surface centered on the optical axis as an envelope surface, so that the following effects can be obtained.

[0018] That is, in the inner peripheral region on the rear surface of the peripheral region, a plurality of total internal reflection prism elements are formed with a first annular concave curved surface centered on the optical axis as an envelope surface, so that the light emitted from the light source that enters this inner peripheral region can be totally reflected by the plurality of total internal reflection prism elements toward the front of the lamp as light of approximately uniform brightness.

[0019] In addition, in the outer peripheral region on the rear surface of the peripheral region, multiple total reflection prism elements are formed with a second annular concave curved surface centered on the optical axis as an envelope surface, so that the light emitted from the light source that enters this outer peripheral region can also be totally reflected by the multiple total reflection prism elements toward the front of the lamp as light of approximately uniform brightness.

[0020] Furthermore, by configuring the plurality of total internal reflection prism elements to have the first and second doubly set annular concave curved surfaces as enveloping surfaces, it is possible to prevent the sizes of not only the total internal reflection prism elements formed on the outer peripheral edge of the inner peripheral region but also the total internal reflection prism elements formed on the outer peripheral edge of the outer peripheral region from becoming too large. Therefore, when molding the lens, it is possible to mold the plurality of total internal reflection prism elements with high precision, thereby enabling accurate light distribution control.

[0021] Thus, according to the present invention, in a vehicle lamp configured to irradiate light emitted from a light source toward the front of the lamp through a lens, it is possible to ensure a sufficient amount of light emitted from the outer peripheral edge of the lens, while also enabling precise light distribution control by the lens.

[0022] Furthermore, by configuring the multiple total reflection prism elements in such a way that the first and second annular concave curved surfaces set in duplicate are formed as the envelope surface, as in the present invention, the lens can be made thinner than when a configuration is adopted in which a single annular concave curved surface is formed as the envelope surface.

[0023] In the above configuration, if each of the multiple total reflection prism elements formed in the inner peripheral region is configured to totally reflect, in a plane including the optical axis, light emitted from a first virtual point light source located rearward of the light source as parallel light directed toward the front of the lamp, and if each of the multiple total reflection prism elements formed in the outer peripheral region is configured to totally reflect, in a plane including the optical axis, light emitted from a second virtual point light source located rearward of the light source and forward of the first virtual point light source as parallel light directed toward the front of the lamp, the following effects can be obtained.

[0024] In other words, although the light source has a certain size, by setting the positions of the first and second virtual point light sources as described above, it becomes easy to totally reflect the light emitted from the light source as approximately parallel light directed toward the front of the lamp by multiple total reflection prism elements in both the inner and outer peripheral regions.

[0025] In this case, if the position of the first virtual point light source is set on the opposite side of the optical axis from the incident area of ​​the light emitted from the first virtual point light source in the inner region, and the position of the second virtual point light source is set on the opposite side of the optical axis from the incident area of ​​the light emitted from the second virtual point light source in the outer region, the light emitted from the light source having a certain size can be totally reflected with even greater accuracy by the multiple total reflection prism elements in both the inner region and the outer region as approximately parallel light directed toward the front of the lamp.

[0026] In the above configuration, if the light source is further configured as a light-emitting element arranged with its light-emitting surface facing forward of the lamp, it becomes easily possible to form a light distribution pattern having a cutoff line by the light emitted from the vehicle lamp.

[0027] In the above configuration, if a plurality of lens elements that control the emission of light arriving from a plurality of total internal reflection prism elements are formed on the front surface of the lens, and if the horizontal cross-sectional shape of these lens elements, including the optical axis, is formed as an envelope curve that is a convex curve centered on the optical axis, then it becomes easy to form the light distribution pattern formed by the light irradiated from the vehicle lamp into a light distribution pattern in which light unevenness is suppressed. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a front view showing a vehicle lamp according to an embodiment of the present invention; [Figure 2] Cross section of line II-II in Figure 1 [Figure 3]FIG. 2A is a front view showing a first lamp unit of the vehicle lamp, and FIG. 2B is a front view showing a second lamp unit of the vehicle lamp. [Figure 4] (a) is a cross-sectional view taken along line IVa-IVa in FIG. 3, and (b) is a cross-sectional view taken along line IVb-IVb in FIG. 3. [Figure 5] (a) is a cross-sectional view taken along line Va-Va in Figure 4, and (b) is a cross-sectional view taken along line Vb-Vb in Figure 4. [Figure 6] 4(a) is a perspective view showing the lens of the first lamp unit as viewed from the direction of arrow VIa in FIG. 4(a), and FIG. 4(b) is a perspective view showing the lens of the second lamp unit as viewed from the direction of arrow VIb in FIG. 4(b). [Figure 7] 4(a) is a perspective view showing the lens of the first lamp unit as viewed from the direction of arrow VIIa in FIG. 4(a), and FIG. 4(b) is a perspective view showing the lens of the second lamp unit as viewed from the direction of arrow VIIb in FIG. 4(b). [Figure 8] Detailed view of part VIII in Figure 5(a) [Figure 9] (a) is a detailed view of part IXa in Figure 8, and (b) is a detailed view of part IXb in Figure 8. [Figure 10] FIG. 1 is a perspective view showing a low beam light distribution pattern formed by light emitted from the vehicle lamp; [Figure 11] FIG. 10 is a diagram showing a first light distribution pattern formed by light emitted from the first lamp unit; [Figure 12] FIG. 10 is a diagram illustrating a process for forming a part of the first light distribution pattern. [Figure 13] FIG. 10 is a diagram showing a second light distribution pattern formed by light emitted from the second lamp unit. [Figure 14] FIG. 4 is a view similar to FIG. 3, illustrating a modification of the embodiment. [Figure 15] 11 is a diagram similar to FIG. 10 illustrating the operation of the above modification. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0030] Fig. 1 is a front view showing a vehicle lamp 10 according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1.

[0031] 1 and 2, the direction indicated by X is "forward of the lamp," the direction indicated by Y is "leftward" ("rightward" when viewed from the front of the lamp) perpendicular to "forward of the lamp," and the direction indicated by Z is "upward." This is the same in other figures.

[0032] As shown in Figures 1 and 2, the vehicle lamp 10 of this embodiment is a headlamp placed at the front end of the vehicle, and is configured so that first and second lamp units 20, 40 are incorporated side by side in the vehicle width direction within a lamp chamber formed by a lamp body 12 and a plain, translucent cover 14 attached to the front end opening.

[0033] The first lamp unit 20 comprises a light-emitting element 22 and a lens 30 arranged on the front side of the lamp, and is configured to irradiate light emitted from the light-emitting element 22 toward the front of the lamp via the lens 30.

[0034] The second lamp unit 40 includes a light-emitting element 42 and a lens 50 arranged on the front side of the lamp, and is configured to irradiate light emitted from the light-emitting element 42 toward the front of the lamp via the lens 50.

[0035] The light-emitting elements 22, 42 of the first and second lamp units 20, 40 are supported on the lamp body 12 via a common substrate 24, and their lenses 30, 50 are supported on the lamp body 12 via a mounting structure not shown.

[0036] The vehicle lamp 10 is configured to form a low beam light distribution pattern (which will be described later) by the light emitted from the first and second lamp units 20, 40.

[0037] Next, the specific configuration of each of the first and second lamp units 20, 40 will be described.

[0038] First, the configuration of the first lamp unit 20 will be described.

[0039] Fig. 3(a) is a front view showing the first lamp unit 20. Fig. 4(a) is a cross-sectional view taken along line IVa-IVa in Fig. 3, and Fig. 5(a) is a cross-sectional view taken along line Va-Va in Fig. 4(a). Fig. 6(a) is a perspective view showing the lens 30 of the first lamp unit 20 as viewed from the direction of arrow VIa in Fig. 4(a), and Fig. 7(a) is a perspective view showing the lens 30 as viewed from the direction of arrow VIIa in Fig. 4(a).

[0040] As shown in these figures, the lens 30 of the first lamp unit 20 has an optical axis Ax extending in the front-to-rear direction of the lamp, and has a circular outer shape centered on the optical axis Ax when viewed from the front of the lamp. The outer dimension of the lens 30 is set to a value of 50 mm or less (for example, approximately 35 mm).

[0041] The light-emitting element 22 is a white light-emitting diode, and is disposed with its light-emitting surface 22a facing forward (specifically, toward the front of the lamp). The light-emitting surface 22a of the light-emitting element 22 has a rectangular outer shape (specifically, a square of approximately 1 x 1 mm). The light-emitting element 22 is disposed with the center position in the left-right direction of the lower edge of the light-emitting surface 22a (hereinafter referred to as the "reference position") positioned on the optical axis Ax of the lens 30.

[0042] The lens 30 is an injection-molded product made of transparent resin, and includes a central region 32 centered on the optical axis Ax, and a peripheral region 34 positioned around the central region 32.

[0043] The rear surface 32b of the central region 32 is configured as a single convex lens surface centered on the optical axis Ax, and is configured to deflect and incident light emitted from the light-emitting element 22 in a direction closer to the optical axis Ax. Specifically, the surface shape of this rear surface 32b is set so as to guide light emitted from the reference position of the light-emitting element 22 to the front surface 30a of the lens 30 as parallel light directed toward the front of the lamp.

[0044] The rear surface 34b of the peripheral region 34 is divided into an inner peripheral region 34b1 and an outer peripheral region 34b2.

[0045] In the inner peripheral region 34b1, a plurality of total internal reflection prism elements 34s1 are formed in a concentric arrangement around the optical axis Ax, and in the outer peripheral region 34b2, a plurality of total internal reflection prism elements 34s2 are formed in a concentric arrangement around the optical axis Ax.

[0046] The plurality of total internal reflection prism elements 34s1, 34s2 are all Fresnel lens type total internal reflection prisms that are configured to receive light emitted from the light emitting element 22 and then totally reflect the light toward the front of the lamp. Specifically, each of the plurality of total internal reflection prism elements 34s1, 34s2 receives light emitted from the reference position of the light emitting element 22 in a manner that refracts the light in a direction away from the optical axis Ax, and then guides the light to the front surface 30a of the lens 30 as parallel light that travels toward the front of the lamp.

[0047] The boundary between the central region 32 and the peripheral region 34 is defined by a circle having a radius of 3 to 5 mm (for example, a radius of about 4 mm) centered on the optical axis Ax. The boundary between the inner region 34b1 and the outer region 34b2 is defined by a circle having a radius of 8 to 12 mm (for example, a radius of about 10 mm) centered on the optical axis Ax.

[0048] Fig. 8 is a detailed view of part VIII in Fig. 5(a), Fig. 9(a) is a detailed view of part IXa in Fig. 8, and Fig. 9(b) is a detailed view of part IXb in Fig. 8.

[0049] As shown in Figure 8, of the multiple total internal reflection prism elements 34s1, 34s2 formed on the rear surface 34b of the peripheral region 34, the multiple total internal reflection prism elements 34s1 located in the inner peripheral region 34b1 are formed with an envelope surface that is a first annular concave curved surface C1 (cross-sectional shape shown by a dotted line in the figure) centered on the optical axis Ax, and the multiple total internal reflection prism elements 34s2 located in the outer peripheral region 34b2 are formed with an envelope surface that is a second annular concave curved surface C2 (cross-sectional shape shown by a dotted line in the figure) centered on the optical axis Ax.

[0050] Each of the plurality of total reflection prism elements 34s1 formed in the inner peripheral region 34b1 is configured to totally reflect, within a plane including the optical axis Ax, light emitted from a first virtual point light source S1 located rearward of the light-emitting surface 22a of the light-emitting element 22 as parallel light directed toward the front of the lamp. The first virtual point light source S1 is located on the opposite side of the optical axis Ax from the incident region of the inner peripheral region 34b1 for light emitted from the first virtual point light source S1. Specifically, the first virtual point light source S1 is located at the intersection of a straight line L1a connecting the inner peripheral edge of the inner peripheral region 34b1 to the right edge (left edge in FIG. 8 ) of the light-emitting surface 22a of the light-emitting element 22 and a straight line L1b connecting the outer peripheral edge of the inner peripheral region 34b1 to the left edge of the light-emitting surface 22a of the light-emitting element 22.

[0051] Each of the plurality of total reflection prism elements 34s2 formed in the outer peripheral region 34b2 is configured to totally reflect, as parallel light, light emitted from a second virtual point light source S2 located rearward of the light-emitting surface 22a of the light-emitting element 22 and forward of the first virtual point light source S1 in a plane including the optical axis Ax. The second virtual point light source S2 is located on the opposite side of the optical axis Ax from the incident region of the outer peripheral region 34b2 for light emitted from the second virtual point light source S2. Specifically, the second virtual point light source S2 is located at the intersection of a straight line L2a connecting the inner peripheral edge of the outer peripheral region 34b2 to the right edge of the light-emitting surface 22a of the light-emitting element 22 and a straight line L2b connecting the outer peripheral edge of the outer peripheral region 34b2 to the left edge of the light-emitting surface 22a of the light-emitting element 22.

[0052] Since the multiple total reflection prism elements 34s1, 34s2 are formed around the entire circumference of the optical axis Ax, the first and second virtual point light sources S1, S2 are also arranged correspondingly to trace circular loci around the optical axis Ax.

[0053] The first annular concave curved surface C1 is formed so that the inner and outer peripheral edges of the inner peripheral region 34b1 are positioned at approximately the same position in the front-to-rear direction of the lamp, and the second annular concave curved surface C2 is formed so that the inner and outer peripheral edges of the outer peripheral region 34b2 are positioned at approximately the same position in the front-to-rear direction of the lamp.

[0054] 9(a), in the inner peripheral region 34b1, the pitch of the plurality of total reflection prism elements 34s1 and the curvature of the first annular concave curved surface C1 are set so that the light emitted from the light emitting element 22 is incident on each of the plurality of total reflection prism elements 34s1 approximately evenly. Also, in the outer peripheral region 34b2, the pitch of the plurality of total reflection prism elements 34s2 and the curvature of the second annular concave curved surface C2 are set so that the light emitted from the light emitting element 22 is incident on each of the plurality of total reflection prism elements 34s2 approximately evenly.

[0055] As a result, of the plurality of total reflection prism elements 34s1 formed in the inner peripheral region 34b1, the total reflection prism elements 34s1 located closer to the outer peripheral edge have larger cross-sectional shapes than the total reflection prism elements 34s1 located closer to the inner peripheral edge of the inner peripheral region 34b1. Similarly, the plurality of total reflection prism elements 34s2 formed in the outer peripheral region 34b2 also have larger cross-sectional shapes than the total reflection prism elements 34s2 located closer to the outer peripheral edge of the outer peripheral region 34b2.

[0056] The multiple total internal reflection prism elements 34s2 formed in the outer peripheral region 34b2 have a cross-sectional shape that is larger overall than the multiple total internal reflection prism elements 34s1 formed in the inner peripheral region 34b1. However, since the multiple total internal reflection prism elements 34s1, 34s2 are formed with the doubly set first and second annular concave curved surfaces C1, C2 as enveloping surfaces, the cross-sectional shape of even the total internal reflection prism elements 34s2 located near the outer edge of the outer peripheral region 34b2 does not become extremely large.

[0057] The lens 30 has a partially thick central region 32, but is thin overall in the peripheral region 34. Specifically, the central region 32 has a maximum thickness of about 4 to 6 mm on the optical axis Ax, while the peripheral region 34 has a substantially constant thickness of about 2 to 4 mm.

[0058] As shown in FIGS. 3 to 6, the front surface 30a of the lens 30 has a configuration in which a plurality of lens elements (which will be described later) are formed on a vertical plane perpendicular to the optical axis Ax.

[0059] The front surface 30a of the lens 30 is divided into five exit areas 30a1, 30a2, 30a3, 30a4, and 30a5.

[0060] The emission region 30a1 is a semicircular region located in the upper half of the front surface 30a, the emission regions 30a2 and 30a4 are semicircular arc-shaped regions extending in a strip shape along the outer periphery of the lower half of the front surface 30a, the emission region 30a3 is a region having a vertically elongated outer shape that spreads out like a fan downward in the lower region of the front surface 30a, and the emission region 30a5 is the remaining region in the lower half of the front surface 30a.

[0061] The emission area 30a1 is divided into a horizontally long (e.g., approximately 2 × 4 mm) grid pattern, and a convex curved lens element 30s1 is assigned to each of the grids. Each lens element 30s1 is configured to deflect light from the light-emitting element 22 that reaches the rear surfaces 32b, 34b of the lens 30 as parallel light downward and then diffuse the light significantly in the left and right directions, and emit the light toward the front of the lamp.

[0062] The emission regions 30a2 and 30a4 are divided into vertical stripes (for example, about 2 mm wide), and convex curved lens elements 30s2 and 30s4 are allocated to each of the stripes.

[0063] Each lens element 30s2 constituting the emission area 30a2 located to the left of the emission area 30a3 (to the right when viewed from the front of the lamp) is configured to emit light from the light-emitting element 22 that reaches the rear surface 34b of the lens 30 as parallel light, deflecting it slightly downward and then diffusing it greatly to the right, toward the front of the lamp.

[0064] Each lens element 30s4 constituting the emission region 30a4 located to the right of the emission region 30a3 is configured to deflect the light from the light-emitting element 22 that arrives as parallel light from the rear surface 34b of the lens 30 slightly upward and then diffuse it greatly to the left, emitting it toward the front of the lamp.

[0065] The left edge of the light exit region 30a3 (the right edge when viewed from the front of the lamp) is formed as a straight line extending directly downward from the optical axis Ax, and the right edge is formed as a straight line extending in a direction tilted to the right from the direction directly downward from the optical axis Ax (specifically, in a direction tilted approximately 15° to the right from the direction directly downward). The upper edge of the light exit region 30a3 is formed as an arc centered on the optical axis Ax. This arc is located slightly outer than the boundary between the central region 32 and the peripheral region 34 of the lens 30. The lower edge of the light exit region 30a3 is formed as the outer peripheral edge of the front surface 30a.

[0066] The light exit region 30a3 is composed of a single lens element 30s3. This lens element 30s3 has a surface shape consisting of a convex free-form surface. That is, the surface of this lens element 30s3 is composed of a free-form surface whose convex curvature gradually changes from its right half 30s3A to its left half 30s3B. This lens element 30s3 is configured to deflect light from the light-emitting element 22 that reaches the rear surface 34b of the lens 30 as parallel light slightly upward and emit the light toward the front of the lamp in a manner that gradually changes the emission direction from the right half 30s3A to the left half 30s3B.

[0067] Like emission region 30a1, emission region 30a5 is divided into vertical and horizontal grid sections, and each section is assigned a convex curved lens element 30s5. However, each lens element 30s5 is configured to deflect light from light-emitting element 22 that reaches lens 30 as parallel light from rear surfaces 32b, 34b slightly downward and then diffuse the light greatly to the left, so that the light is emitted toward the front of the lamp.

[0068] Next, the configuration of the second lamp unit 40 will be described.

[0069] Fig. 3(b) is a front view showing the second lamp unit 40. Fig. 4(b) is a cross-sectional view taken along line IVb-IVb in Fig. 3, and Fig. 5(b) is a cross-sectional view taken along line Vb-Vb in Fig. 4(b). Fig. 6(b) is a perspective view showing the lens 50 of the second lamp unit 40 as viewed from the direction of arrow VIb in Fig. 4(b), and Fig. 7(b) is a perspective view showing the lens 50 as viewed from the direction of arrow VIIb in Fig. 4(b).

[0070] As shown in these figures, the configuration and arrangement of the light-emitting element 42 in the second lamp unit 40 are the same as those of the light-emitting element 22 in the first lamp unit 20, and the basic configuration and arrangement of the lens 50 are the same as those of the lens 30 in the first lamp unit 20, but the configuration of its front surface 50a is different from that of the lens 30.

[0071] That is, the lens 50 of the second lamp unit 40 is also an injection-molded product made of transparent resin, and has a central region 52 centered on the optical axis Ax extending in the fore-and-aft direction of the lamp, and a peripheral region 54 located around this central region 52.

[0072] The configurations of the rear surface 52b of the central region 52 and the rear surface 54b of the peripheral region 54 are exactly the same as those of the lens 30 of the first lamp unit 20. That is, the rear surface 54b of the peripheral region 54 is divided into an inner peripheral region 54b1 and an outer peripheral region 54b2, and each of these regions has a plurality of total internal reflection prism elements 54s1, 54s2 arranged concentrically around the optical axis Ax.

[0073] The front surface 50a of the lens 50 is divided into nine emission regions 50a1, 50a2L, 50a2R, 50a3L, 50a3R, 50a4L, 50a4R, 50a5L, and 50a5R, each of which has a plurality of lens elements (described later).

[0074] The nine emission regions 50a1 to 50a5R are formed as strip-shaped regions extending in the vertical direction along a cylindrical surface that bulges out towards the front of the lamp and extends in the vertical direction.

[0075] The exit region 50a1 is formed with a wide width (for example, a width of about 6 mm) centered on the optical axis Ax, and on both the left and right sides thereof, exit regions 50a2L, 50a2R, exit regions 50a3L, 50a3R, exit regions 50a4L, 50a4R, and exit regions 50a5L, 50a5R are formed adjacent to each other in this order, each with a width of, for example, about 4 mm.

[0076] Each of the nine emission regions 50a1-50a5R is divided by a fixed vertical width (for example, a width of about 2 mm), and convex curved lens elements 50s1, 50s2L, 50s2R, 50s3L, 50s3R, 50s4L, 50s4R, 50s5L, and 50s5R are assigned to each of the emission regions 50. Each of the plurality of lens elements 50s1-50s5R is configured to deflect light from light-emitting element 42 that has reached lens 50 as parallel light downward and then diffuse the light in the left-right directions, and emit the light toward the front of the lamp.

[0077] As shown in FIG. 5(b), the horizontal cross-sectional shapes of the lens elements 50s1-50s5R, including the optical axis Ax, are formed such that the envelope curve of the cross-sectional shape is a convex curve C3 centered on a point on the optical axis Ax. As a result, light emitted from each lens element 50s1 constituting the central light-emitting region 50a1 is diffused evenly to the left and right, while light emitted from each lens element 50s2L-50s5R constituting the remaining light-emitting regions 50a2L-50a5R is diffused unevenly to the left and right because the inclination angle of the convex curve C3 toward the rear of the lamp gradually increases as the distance from the optical axis Ax increases to the left and right. That is, the degree of unevenness increases in the order of lens elements 50s2L, 50s2R, lens elements 50s3L, 50s3R, lens elements 50s4L, 50s4R, and lens elements 50s5L, 50s5R.

[0078] FIG. 10 is a perspective view showing a low beam light distribution pattern PL-1 formed by light emitted from the vehicle lamp 10 on a virtual vertical screen located 25 m ahead of the lamp.

[0079] The low beam light distribution pattern PL-1 is a low beam light distribution pattern for left light distribution, and a stepped cutoff line CL is formed at the upper end thereof.

[0080] The stepped cutoff line CL has a shape in which a lower cutoff line CL1 and an upper cutoff line CL2, which extend horizontally at different levels on the left and right, are connected via an inclined portion CL3. The stepped cutoff line CL is formed so that the lower cutoff line CL1 is located on the oncoming lane side of the VV line, which is a vertical line passing through the HV line, which is the vanishing point in front of the lamp, and the inclined portion CL3 and the upper cutoff line CL2 are located on the own lane side. The upper cutoff line CL2 is located slightly above the HH line, which is a horizontal line passing through the HV line.

[0081] In the low beam light distribution pattern PL-1, elbow point E, which is the intersection of the lower cutoff line CL1 and inclined portion CL3, is located approximately 0.5 to 0.6° below HV, and inclined portion CL3 extends diagonally upward and left from elbow point E at an inclination angle of 15° with respect to the horizontal. In this low beam light distribution pattern PL-1, a high luminous intensity region HZ is formed in the vicinity of the lower left of elbow point E.

[0082] The low beam light distribution pattern PL-1 is formed as a composite light distribution pattern by superimposing a first light distribution pattern PL-1A formed by light irradiated from the first lamp unit 20 and a second light distribution pattern PL-1B formed by light irradiated from the second lamp unit 40.

[0083] FIG. 11 is a diagram showing the first light distribution pattern PL-1A.

[0084] As shown in FIG. 11, the first light distribution pattern PL-1A is formed as a composite light distribution pattern in which five light distribution patterns PA1, PA2, PA3, PA4, and PA5 are superimposed.

[0085] Light distribution pattern PA1 is a light distribution pattern formed by light emitted from emission region 30a1 on front surface 30a of lens 30, and is formed as a horizontally elongated light distribution pattern that has a relatively large vertical width and extends widely in the left-right direction below line HH. This light distribution pattern PA1 forms a wide diffusion region of low-beam light distribution pattern PL-1.

[0086] Light distribution pattern PA2 is a light distribution pattern formed by light emitted from emission region 30a2 on front surface 30a of lens 30, and is formed as a horizontally elongated bright light distribution pattern that has a narrow vertical width below line HH and expands rightward from near line VV. The upper edge of light distribution pattern PA2 forms a lower cutoff line CL1 of low beam light distribution pattern PL-1.

[0087] Such a light distribution pattern PA2 is formed because the angle of view of the light-emitting surface 22a of the light-emitting element 22 from the outer edge of the outer peripheral region 34b2 of the peripheral region 34 is extremely small, and therefore the light distribution pattern formed by the light emitted from the emission region 30a2 located in front of the lamp tends to be small and bright.

[0088] Light distribution pattern PA3 is a light distribution pattern formed by light emitted from emission region 30a3 on front surface 30a of lens 30, and is formed as a small, bright light distribution pattern extending diagonally upward and leftward with a narrow vertical width near the lower portion of HV. The upper edge of light distribution pattern PA3 forms inclined portion CL3 of low-beam light distribution pattern PL-1 and the right end of upper cutoff line CL2. The process of forming light distribution pattern PA3 will be described later.

[0089] Light distribution pattern PA4 is a light distribution pattern formed by light emitted from emission region 30a4 on front surface 30a of lens 50, and is formed as a horizontally elongated bright light distribution pattern with a narrow vertical width that extends leftward from the left side of line VV approximately along line HH. This light distribution pattern PA4 is configured to form an upper cutoff line CL2 of low beam light distribution pattern PL-1 with its upper edge. At this time, this light distribution pattern PA4 is formed so that its right end overlaps with light distribution pattern PA3 and smoothly connects to it.

[0090] The reason why such a light distribution pattern PA4 is formed is that, as in the case of light distribution pattern PA2, the angle of view of the light-emitting surface 22a of the light-emitting element 22 from the outer edge of the outer peripheral region 34b2 of the peripheral region 34 is extremely small, and therefore the light distribution pattern formed by the emitted light from the emission region 30a4 located in front of the lamp tends to be small and bright.

[0091] Light distribution pattern PA5 is a light distribution pattern formed by light emitted from emission region 30a5 on front surface 30a of lens 30, and is formed as a horizontally elongated, relatively bright light distribution pattern that extends leftward from near the left side of line VV with a relatively narrow vertical width, spanning light distribution pattern PA4 and light distribution pattern PA1, and its right end overlaps with light distribution pattern PA3.

[0092] FIG. 12 is a diagram for explaining the process of forming the light distribution pattern PA3, and shows a perspective view of a part of the front surface 30a of the lens 30 and a part of the first light distribution pattern PL-1A.

[0093] As shown in Figure 12, the light distribution pattern PA3 formed by the light emitted from the lens element 30s3 that constitutes the emission area 30a3 on the front surface 30a of the lens 30 is formed so that its upper edge extends from the inclined portion CL3 of the low beam light distribution pattern PL-1 to the right end of the upper cutoff line CL2, as described above.

[0094] 12, the light distribution pattern PA3o indicated by the two-dot chain line is the light distribution pattern that would be formed if lens element 30s3 were not formed in emission region 30a3, and is formed to extend diagonally upward and leftward near the lower side of inclined portion CL3. The upper edge of this light distribution pattern PA3o is formed as a clear light-dark boundary line. This is because light-emitting element 22 is arranged with the lower edge of its light-emitting surface 22a positioned on optical axis Ax of lens 30.

[0095] In reality, because lens element 30s3 is formed in output region 30a3, light distribution pattern PA3o changes to look like light distribution pattern PA3. This is because lens element 30s3 is configured with a free-form surface whose convex curvature gradually changes from right half 30s3A to left half 30s3B, so that collimated light that has reached front surface 30a of lens 30 is deflected slightly upward and the output direction gradually changes from right half 30s3A to left half 30s3B.

[0096] Furthermore, the emission area 30a3 is composed of a single lens element 30s3, and there are no steps on its surface, so that the light distribution pattern PA3 does not inadvertently form a light pool in the space above the inclined portion CL3 that could cause glare.

[0097] FIG. 13 is a diagram showing the second light distribution pattern PL-1B.

[0098] As shown in FIG. 13, the second light distribution pattern PL-1B is formed as a composite light distribution pattern in which nine light distribution patterns PB1, PB2L, PB2R, PB3L, PB3R, PB4L, PB4R, PB5L, and PB5R are superimposed.

[0099] The light distribution pattern PB1 is a light distribution pattern formed by light emitted from the emission area 50a1 on the front surface 50a of the lens 50, and is formed as a horizontally elongated light distribution pattern that extends evenly to both the left and right sides below the line HH and centered on the line VV.

[0100] The pair of left and right light distribution patterns PB2L and PB2R are light distribution patterns formed by light emitted from a pair of left and right exit areas 50a2L and 50a2R on the front surface 50a of the lens 50, and are horizontally elongated light distribution patterns smaller than the light distribution pattern PB1, and are formed in a symmetrical positional relationship with their center positions shifted from the VV line.

[0101] The pair of left and right light distribution patterns PB3L and PB3R are light distribution patterns formed by light emitted from a pair of left and right exit areas 50a3L and 50a3R on the front surface 50a of the lens 50, and are horizontally elongated light distribution patterns smaller than the light distribution patterns PB2L and PB2R, and are formed in a symmetrical positional relationship with their center positions shifted from the VV line.

[0102] The pair of left and right light distribution patterns PB4L and PB4R are light distribution patterns formed by light emitted from a pair of left and right exit areas 50a4L and 50a4R on the front surface 50a of the lens 50, and are horizontally elongated light distribution patterns smaller than the light distribution patterns PB3L and PB3R, and are formed in a symmetrical positional relationship with their center positions shifted from the VV line.

[0103] The pair of left and right light distribution patterns PB5L and PB5R are light distribution patterns formed by light emitted from a pair of left and right exit areas 50a5L and 50a5R on the front surface 50a of the lens 50, and are horizontally elongated light distribution patterns smaller than the light distribution patterns PB4L and PB4R, and are formed in a symmetrical positional relationship with their center positions shifted from the VV line.

[0104] Each of these four pairs of left and right light distribution patterns PB2L to PB5R is formed in a symmetrical positional relationship with its center position shifted from line VV because the horizontal cross-sectional shape of the multiple lens elements 50s2L to 50s5R is formed with a convex curve C3 as an envelope as shown in Figure 5(b).

[0105] Therefore, the second light distribution pattern PL-1B is formed as a light distribution pattern having a luminous intensity distribution in which the luminous intensity gradually decreases from the VV line in both the left and right directions, thereby effectively suppressing the occurrence of uneven light distribution.

[0106] The second light distribution pattern PL-1B is formed so that the positions of the upper edges of the nine light distribution patterns PB1 to PB5R substantially coincide with each other in the vicinity below the lower cutoff line CL1. This is achieved by appropriately adjusting the vertical tilt angles of the multiple lens elements 50s1 to 50s5R that constitute the nine emission regions 50a1 to 50a5R.

[0107] As shown in FIG. 10, the low beam light distribution pattern PL-1 is formed as a composite light distribution pattern of the first light distribution pattern PL-1A and the second light distribution pattern PL-1B, so that the high luminous intensity region HZ formed near the lower left of the elbow point E is extremely bright.

[0108] Next, the effects of this embodiment will be described.

[0109] The vehicle lamp 10 of this embodiment is configured to form a low beam light distribution pattern PL having a stepped cutoff line CL by irradiating the light emitted from the light-emitting elements 22, 42 (light sources) of the first and second lamp units 20, 40 through the lenses 30, 50 toward the front of the lamp.In each lens 30, 50, the rear surfaces 34b, 54b of the peripheral regions 34, 54 located around the central regions 32, 52 centered on the optical axis Ax extending in the fore-and-aft direction of the lamp are formed with a plurality of total reflection prism elements 34s1, 34s2, 54s1, 54s2 arranged concentrically around the optical axis Ax, which receive the light emitted from the light-emitting elements 22, 42 and then totally reflect it toward the front of the lamp.As a result, the light emitted from the light-emitting elements 22, 42 can be used as forward illumination light over a wide range.

[0110] In addition, the rear surfaces 34b, 54b of the peripheral regions 34, 54 are divided into inner peripheral regions 34b1, 54b1 and outer peripheral regions 34b2, 54b2, and in the inner peripheral regions 34b1, 54b1, the plurality of total internal reflection prism elements 34s1, 54s1 are formed with the first annular concave curved surface C1 centered on the optical axis Ax as an envelope surface. Therefore, the light emitted from the light emitting elements 22, 42 and incident on the inner peripheral regions 34b1, 54b1 is substantially reflected by the plurality of total internal reflection prism elements 34s1, 54s1. The light can be totally reflected toward the front of the lamp as light of uniform brightness, and in the outer peripheral region 34b2, 54b2, the multiple total reflection prism elements 34s2, 54s2 are formed with the second annular concave curved surface C2 centered on the optical axis Ax as the envelope surface, so that the light emitted from the light-emitting elements 22, 42 that enters the outer peripheral region 34b2, 54b2 can also be totally reflected toward the front of the lamp as light of approximately uniform brightness by the multiple total reflection prism elements 34s2, 54s2.

[0111] Furthermore, by configuring the plurality of total internal reflection prism elements 34s1, 34s2, 54s1, 54s2 so that the first and second doubly set circular concave curved surfaces C1, C2 form enveloping surfaces, it is possible to prevent the sizes of not only the total internal reflection prism elements 34s1, 54s1 formed on the outer periphery of the inner peripheral region 34b1, 54b1 but also the total internal reflection prism elements 34s2, 54s2 formed on the outer periphery of the outer peripheral region 34b2, 54b2 from becoming too large. Therefore, when molding the lenses 30, 50, it is possible to mold the plurality of total internal reflection prism elements 34s1, 34s2, 54s1, 54s2 with high precision, thereby enabling accurate light distribution control.

[0112] Thus, according to this embodiment, in a vehicle lamp 10 configured to irradiate light emitted from the light-emitting elements 22, 42 of the first and second lamp units 20, 40 toward the front of the lamp via lenses 30, 50, it is possible to ensure a sufficient amount of light emitted from the outer peripheral edges of the lenses 30, 50, while allowing light distribution control by the lenses 30, 50 to be performed with high precision.

[0113] Furthermore, as in this embodiment, by configuring the multiple total reflection prism elements 34s1, 34s2, 54s1, 54s2 to have the first and second annular concave curved surfaces C1, C2 set doubly as envelope surfaces, the peripheral regions 34, 54 of the lenses 30, 50 can be made thinner than in a configuration in which a single annular concave curved surface is formed as the envelope surface.

[0114] In addition, in the lenses 30, 50 of this embodiment, the central regions 32, 52 are formed to be thicker than the peripheral regions 34, 54, but by configuring the central regions 32, 52 to have gates for injection molding the lenses 30, 50, it is possible to easily mold the lenses 30, 50.

[0115] In this embodiment, each of the multiple total reflection prism elements 34s1, 54s1 formed in the inner peripheral region 34b1, 54b1 on the rear surface 34b, 54b of the peripheral region 34, 54 is configured to totally reflect, in a plane including the optical axis Ax, the light emitted from a first virtual point light source S1 located rearward of the light-emitting element 22, 42 as parallel light directed toward the front of the lamp, and each of the multiple total reflection prism elements 34s2, 54s2 formed in the outer peripheral region 34b2, 54b2 is configured to totally reflect, in a plane including the optical axis Ax, the light emitted from a second virtual point light source S2 located rearward of the light-emitting element 22, 42 and forward of the first virtual point light source S1 as parallel light directed toward the front of the lamp, thereby obtaining the following advantageous effects.

[0116] That is, the light-emitting elements 22, 42 have light-emitting surfaces 22a, 42a of a certain size, and the light emitted from these light-emitting elements 22, 42 can be totally reflected in the inner regions 34b1, 54b1 by a plurality of total reflection prism elements 34s1, 54s1 as approximately parallel light directed toward the front of the lamp, and can be totally reflected in the outer regions 34b2, 54b2 by a plurality of total reflection prism elements 34s2, 54s2 as approximately parallel light directed toward the front of the lamp.

[0117] In this case, the first virtual point light source S1 is located on the opposite side of the optical axis Ax from the incident area of ​​the light emitted from the first virtual point light source S1 in the inner peripheral side regions 34b1, 54b1, and the second virtual point light source S2 is located on the opposite side of the optical axis Ax from the incident area of ​​the light emitted from the second virtual point light source S2 in the outer peripheral side regions 34b2, 54b2, so that the following effects can be obtained.

[0118] That is, the light emitted from the light-emitting surfaces 22a, 42a of the light-emitting elements 22, 42, which have a certain size, can be totally reflected with high precision in the inner regions 34b1, 54b1 by a plurality of total reflection prism elements 34s1, 54s1 as approximately parallel light directed toward the front of the lamp, and in the outer regions 34b2, 54b2, it can be totally reflected with high precision by a plurality of total reflection prism elements 34s2, 54s2 as approximately parallel light directed toward the front of the lamp.

[0119] In this embodiment, the light sources of the first and second lamp units 20, 40 are composed of light-emitting elements 22, 42 arranged with their light-emitting surfaces 22a, 42a facing forward of the lamp, so that it is easy to form a low beam light distribution pattern PL-1 having a stepped cutoff line CL using light emitted from the vehicle lamp 10.

[0120] In this embodiment, the first light distribution pattern PL-1A formed by the light irradiated from the first lamp unit 20 forms a stepped cutoff line CL of the low beam light distribution pattern PL-1, and the lens 50 in the second lamp unit 40 is configured such that the front surface 50a is divided into nine emission areas 50a1, 50a2L, 50a2R, 50a3L, 50a3R, 50a4L, 50a4R, 50a5L, and 50a5R extending in the vertical direction, and a plurality of lens elements 50a1, 50a2L, 50a2R, 50a3L, 50a3R, 50a4L, 50a4R, 50a5L, and 50a5R are formed, and the horizontal cross-sectional shape including the optical axis Ax is formed with a convex curve C3 centered on the optical axis Ax as an envelope, so that the following effects can be obtained.

[0121] That is, the second light distribution pattern PL-1B formed by the light emitted from the second lighting unit 40 is formed as a composite light distribution pattern of nine light distribution patterns PB1, PB2L, PB2R, PB3L, PB3R, PB4L, PB4R, PB5L, and PB5R formed by the light emitted from the nine emission areas 50a1 to 50a5R, but these are formed with their sizes and formation positions changed from each other, so the second light distribution pattern PL-1B can be formed as a light distribution pattern in which light unevenness is suppressed.

[0122] In the above embodiment, the light emitting surface 22a of the light emitting element 22 has an outer shape of about 1×1 mm, but it is also possible to use a light emitting surface having a shape other than this.

[0123] In the above embodiment, the rear surface 32b of the central region 32 of the lens 30 of the first lamp unit 20 is described as being composed of a single convex lens surface, but other configurations (such as a configuration formed in the shape of a Fresnel lens) can also be adopted.

[0124] In the above embodiment, the lenses 30, 50 of the first and second lamp units 20, 40 are described as both having a circular outer shape when viewed from the front of the lamp, but it is also possible to adopt a configuration having an outer shape other than this.

[0125] In the above embodiment, the lenses 30 and 50 are described as being injection molded products, but other configurations (for example, compression molded products) can also be used.

[0126] In the above embodiment, the light emitted from the vehicle lamp 10 is described as forming a low beam light distribution pattern PL-1 for left light distribution having a stepped cutoff line CL, but it is also possible to configure the vehicle lamp 10 to form other light distribution patterns.

[0127] Next, a modification of the above embodiment will be described.

[0128] FIG. 14 is a view similar to FIG. 3, showing first and second lamp units 120, 140 of a vehicle lamp according to this modified example.

[0129] As shown in FIG. 14, in this modified example, the configuration of the second lamp unit 140 is exactly the same as in the above embodiment, but the configuration of the lens 130 of the first lamp unit 120 is partially different from that in the above embodiment.

[0130] That is, as shown in FIG. 14(a), the lens 130 of this modified example also has a central region 132 and a peripheral region 134, and the configuration of the rear surfaces 132b, 134b is exactly the same as in the above embodiment, and the rear surface 134b of the peripheral region 134 is divided into an inner region 134b1 and an outer region 134b2.

[0131] Furthermore, lens 130 of this modified example has its front surface 130a divided into five emission regions 130a1, 130a2, 130a3, 130a4, and 130a5. Specifically, front surface 130a of lens 130 is roughly divided into two regions concentrically about optical axis Ax, with a pair of upper and lower emission regions 130a1 and 130a5 arranged on the inner periphery, and a pair of left and right emission regions 130a2 and 130a4 and a pair of upper and lower emission regions 130a3 arranged on the outer periphery.

[0132] The emission region 130a1 located at the upper part of the inner periphery is divided into a horizontally long grid pattern, similar to the emission region 30a1 of the lens 30 of the first lamp unit 20 in the above embodiment, and a lens element 130s1 with a convex curved surface is assigned to each of the grids. Each lens element 130s1 is configured to deflect light from the light-emitting element 22 that reaches the rear surfaces 132b, 134b of the lens 130 as parallel light downward and then diffuse the light significantly in the left-right directions, and emit the light toward the front of the lamp.

[0133] The pair of left and right emission regions 130a2, 130a4 are divided into two halves, top and bottom, and are divided into vertical stripes, and convex curved lens elements 130s2, 130s4 are allocated to each of these.

[0134] Each lens element 130s2 constituting the emission region 130a2 located on the left side is configured to deflect the light from the light-emitting element 22 that arrives as parallel light from the rear surface 134b of the lens 130 slightly downward and then diffuse it greatly to the right, emitting it toward the front of the lamp.

[0135] Each lens element 130s4 constituting the emission region 130a4 located on the right side is configured to deflect the light from the light-emitting element 22 that arrives as parallel light from the rear surface 134b of the lens 130 slightly upward and then diffuse it greatly to the left, emitting it toward the front of the lamp.

[0136] The pair of upper and lower emission regions 130a3 are divided into diagonal vertical stripes, and each of these regions is assigned a convex curved lens element 130s3. Each lens element 130s3 is formed to extend in a direction tilted 15° to the left (right when viewed from the front of the lamp) with respect to the vertical direction, so that light from the light-emitting element 22 that reaches the rear surface 134b of the lens 130 as parallel light is deflected slightly upward and then slightly deflected and diffused in a direction perpendicular to the 15° tilt direction, and emitted toward the front of the lamp.

[0137] The emission region 130a5 located at the bottom of the inner circumference is divided into vertical stripes, similar to the emission region 30a5 of the lens 30 of the first lamp unit 20 in the above embodiment, and a lens element 130s5 with a convex curved surface is assigned to each of the vertical stripes. Each lens element 130s5 is configured to deflect light from the light-emitting element 22 that reaches the rear surfaces 132b, 134b of the lens 130 as parallel light slightly downward and then diffuse the light greatly to the left, causing the light to be emitted toward the front of the lamp.

[0138] FIG. 15 is a perspective view showing a light distribution pattern PL-2 for low beam formed on the virtual vertical screen by light emitted from a vehicle lamp according to this modified example.

[0139] The low beam light distribution pattern PL-2 is formed as a composite light distribution pattern by superimposing a first light distribution pattern PL-2C formed by light irradiated from the first lamp unit 120 and a second light distribution pattern PL-2B formed by light irradiated from the second lamp unit 140.

[0140] The second light distribution pattern PL-2B is exactly the same as the second light distribution pattern PL-1B (see FIG. 13) formed by the light emitted from the second lamp unit 40 of the above embodiment.

[0141] On the other hand, the first light distribution pattern PL-2C is formed as a composite light distribution pattern in which five light distribution patterns PC1, PC2, PC3, PC4, and PC5 are superimposed.

[0142] Light distribution pattern PC1 is a light distribution pattern formed by light emitted from emission region 130a1 on front surface 130a of lens 130, and is formed as a horizontally elongated light distribution pattern that has a relatively large vertical width and extends widely in the left-right direction below line HH. This light distribution pattern PC1 forms a wide diffusion region of low beam light distribution pattern PL-2.

[0143] Light distribution pattern PC2 is a light distribution pattern formed by light emitted from emission region 130a2 on front surface 130a of lens 130, and is formed as a horizontally elongated bright light distribution pattern that has a narrow vertical width below line HH and expands rightward from line VV. The upper edge of light distribution pattern PC2 forms a lower cutoff line CL1 of light distribution pattern PL-2 for low beam.

[0144] Light distribution pattern PC3 is a light distribution pattern formed by light emitted from a pair of upper and lower emission regions 130a3 on front surface 130a of lens 130, and is formed as a small, bright light distribution pattern extending diagonally upward and leftward with a narrow vertical width near the lower side of HV. The upper edge of this light distribution pattern PC3 forms inclined portion CL3 of light distribution pattern PL-2 for low beam.

[0145] Light distribution pattern PC4 is a light distribution pattern formed by light emitted from emission region 130a4 on front surface 130a of lens 130, and is formed as a horizontally elongated bright light distribution pattern with a narrow vertical width extending leftward from the left side of line VV approximately along line HH. This light distribution pattern PC4 is configured to form an upper cutoff line CL2 of low beam light distribution pattern PL-2 with its upper edge. At this time, this light distribution pattern PC4 is formed with its right end portion overlapping with light distribution pattern PC3.

[0146] Light distribution pattern PC5 is a light distribution pattern formed by light emitted from emission region 130a5 on front surface 130a of lens 130, and is formed as a relatively bright horizontally elongated light distribution pattern that extends leftward from near the left side of line VV with a relatively narrow vertical width, spanning light distribution pattern PC4 and light distribution pattern PC1, and its right end portion overlaps with light distribution pattern PC3.

[0147] Even when the configuration of this modified example is adopted, substantially the same effects as those of the above embodiment can be obtained.

[0148] Furthermore, by adopting the configuration of this modified example, it is possible to easily ensure sufficient brightness in the vicinity of the stepped cutoff line CL in the low beam light distribution pattern PL-2.

[0149] It should be noted that the numerical values ​​shown as the specifications in the above embodiment and its modified examples are merely examples, and it goes without saying that these may be set to different values ​​as appropriate.

[0150] Furthermore, the present invention is not limited to the configurations described in the above embodiment and its modified examples, and various other modified configurations can be adopted. [Explanation of symbols]

[0151] 10 Vehicle lighting fixtures 12 Lamp body 14 Translucent cover 20, 120 First lighting unit 22, 42 Light-emitting element (light source) 22a, 42a Light-emitting surface 24 PCB 30, 50, 130 lenses 30a, 50a, 130a front Emission area 30s1, 30s2, 30s3, 30s4, 30s5, 50s1, 50s2L, 50s2R, 50s3L, 50s3R, 50s4L, 50s4R, 50s5L, 50s5R, 130s1, 130s2, 130s3, 130s4, 130s5 lens elements 30s3A right half 30s3B left half 32, 52, 132 central area 32b, 34b, 52b, 54b, 132b, 134b rear 34, 54, 134 Surrounding areas 34b1, 54b1, 134b1 Inner area 34b2, 54b2, 134b2 Outer area 34s1, 34s2, 54s1, 54s2 Total reflection prism elements 40, 140 Second lighting unit Ax optical axis C1 First circular concave surface C2 Second circular concave surface C3 convex curve CL stepped cut-off line CL1 Lower cutoff line CL2 Upper cutoff line CL3 Slope E Elbow point HZ High luminosity region L1a, L1b, L2a, L2b straight line PA1, PA2, PA3, PA4, PA5, PB1, PB2L, PB2R, PB3L, PB3R, PB4L, PB4R, PB5L, PB5R, PC1, PC2, PC3, PC4, PC5 Light distribution pattern PL-1, PL-2 low beam light distribution pattern PL-1A, PL-2C 1st light distribution pattern PL-1B, PL-2B Second light distribution pattern S1 First virtual point light source S2 Second virtual point light source

Claims

1. A vehicle lamp including a light source and a lens, and configured to irradiate light emitted from the light source toward a front of the lamp through the lens, The lens has a central region centered on an optical axis extending in a front-to-rear direction of the lamp, and a peripheral region located around the central region, a plurality of total reflection prism elements that cause the incident light from the light source to be totally reflected toward the front of the lamp are formed on the rear surface of the peripheral area in a state of being arranged concentrically around the optical axis, The rear surface of the peripheral region is divided into an inner peripheral region and an outer peripheral region, a plurality of total reflection prism elements each having an envelope surface formed as a first annular concave curved surface centered on the optical axis in the inner peripheral region, and a second annular concave curved surface centered on the optical axis in the outer peripheral region.

2. each of the plurality of total reflection prism elements formed in the inner peripheral region is configured to totally reflect, within a plane including the optical axis, light emitted from a first imaginary point light source located rearward of the light source, as parallel light directed toward a front direction of the lamp; 2. The vehicular lamp according to claim 1, wherein each of the plurality of total reflection prism elements formed in the outer peripheral region is configured to totally reflect light emitted from a second imaginary point light source located rearward of the light source and forward of the first imaginary point light source in a plane including the optical axis as parallel light directed toward a front of the lamp.

3. the first virtual point light source is located on an opposite side of the optical axis to an incident region of the inner peripheral region into which light emitted from the first virtual point light source is incident, 3. The vehicle lamp according to claim 2, wherein the second imaginary point light source is located on an opposite side of the optical axis from an incident area of ​​the light emitted from the second imaginary point light source in the outer peripheral area.

4. 4. The vehicle lamp according to claim 1, wherein the light source is configured as a light-emitting element arranged with a light-emitting surface facing forward of the lamp.

5. a plurality of lens elements are formed on the front surface of the lens to control the emission of light that has reached the lens from the plurality of total reflection prism elements; The vehicle lamp according to any one of claims 1 to 3, characterized in that the horizontal cross-sectional shape of the plurality of lens elements, including the optical axis, is formed with a convex curved envelope centered on the optical axis.

Images