Vehicle headlight

Abstract

A first primary lens (22) collimates light from each of a plurality of first light sources (21). A first lens array (23) has a plurality of first lens elements (231). The collimated light entering the plurality of first lens elements from the first optical element is output from the plurality of first lens elements. A second primary lens (22) collimates light from each of a plurality of second light sources (31). A second lens array (33) has a plurality of second lens elements (331). The collimated light entering the plurality of second lens elements from the second optical element is output from the plurality of second lens elements. The plurality of first light sources (21) are disposed at a first interval along a first direction. The plurality of second light sources (31) are disposed at a second interval along the first direction. The first interval and the second interval are different from each other.

Description

Vehicle headlights

[0001] The present disclosure relates to a vehicle headlamp.

[0002] Patent Documents 1 and 2 disclose vehicle headlamps that perform adaptive driving beam (ADB) light distribution, which divides a high beam light distribution pattern into multiple areas and controls the light irradiation for each of the divided areas. The ADB light distribution is performed by a projector-type lamp having multiple light sources and a projection lens.

[0003] Japanese Patent Publication No. 2009-179113 Japanese Patent Publication No. 2013-097886

[0004] Incidentally, the inventors of the present invention have found that an ADB light distribution can be formed using a lens array.

[0005] The present disclosure aims to provide a vehicle headlamp that forms an ADB light distribution using a lens array.

[0006] A vehicle headlamp according to a first aspect of the present disclosure comprises: a first optical unit having: a plurality of first light sources whose lighting can be controlled individually; a first optical element that converts light from each of the plurality of first light sources into parallel light; and a first lens array having a plurality of first lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light incident on the entrance surface from the first optical elements from the exit surface; and a second optical unit having: a plurality of second light sources whose lighting can be controlled individually; a second optical element that converts light from each of the plurality of second light sources into parallel light; and a second lens array having a plurality of second lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light incident on the entrance surface from the second optical elements from the exit surface; wherein the plurality of first light sources are arranged at a first interval along a first direction and the plurality of second light sources are arranged at a second interval along the first direction, and the first interval and the second interval are different from each other.

[0007] According to the present disclosure, it is possible to provide a vehicle headlamp that forms an ADB light distribution using a lens array.

[0008] 7 is a plan view illustrating a configuration of a vehicle headlamp according to an embodiment of the present disclosure. FIG. 8 is a view illustrating a first light distribution pattern formed by light emitted from a first optical unit. FIG. 9 is a view illustrating a second light distribution pattern formed by light emitted from a second optical unit. FIG. 10 is a view illustrating a high beam light distribution pattern formed by light emitted from a vehicle headlamp. FIG. 11 is a view for explaining the relationship between the ratio of the entrance thickness to the exit thickness of a lens element and the projection angle interval of a projected image of a light source. FIG. 12 is a view illustrating a light distribution pattern formed by light emitted from the optical unit of FIG. 6. FIG. 13 is a view for explaining the relationship between the F-number of a primary lens and the projection angle interval and the projected image size of a projected image of a light source. FIG. 14 is a view illustrating a light distribution pattern formed by light emitted from the optical unit of FIG. 15. FIG. 16 is a plan view illustrating a configuration of a third optical unit according to Modification 1. FIG. 17 is a view illustrating a third light distribution pattern formed by light emitted from the third optical unit. FIG. 18 is a view illustrating a high beam light distribution pattern formed by light emitted from a vehicle headlamp according to Modification 1. 13 is a diagram for explaining the relationship between the arrangement interval of lens elements and the projection angle interval of the projected image of the light source. FIG. 14 is a diagram illustrating a light distribution pattern formed by light emitted from the optical unit of FIG. 12. FIG. 15 is a plan view illustrating an example of the configuration of a fourth optical unit according to Modification 2. FIG. 16 is a longitudinal sectional view illustrating an example of the configuration of the fourth optical unit according to Modification 2.

[0009] Hereinafter, examples of embodiments of the present disclosure will be described with reference to the drawings. In the drawings, arrow U indicates the upward direction of the illustrated structure. Arrow D indicates the downward direction of the illustrated structure. Arrow F indicates the forward direction of the illustrated structure. Arrow B indicates the rearward direction of the illustrated structure. Arrow R indicates the rightward direction of the illustrated structure. Arrow L indicates the leftward direction of the illustrated structure. These directions are relative directions set for the vehicle headlamp 1 shown in FIG. 1, and the direction of light emitted by the vehicle headlamp 1 is the forward direction.

[0010] Fig. 1 is a plan view illustrating the configuration of a vehicle headlamp 1 according to an embodiment of the present disclosure. As shown in Fig. 1, the vehicle headlamp 1 includes a first optical unit 2 and a second optical unit 3. The vehicle headlamp 1 includes an outer lens and a housing (not shown), and the first optical unit 2 and the second optical unit 3 are disposed within a lamp chamber formed by the outer lens and the housing.

[0011] The first optical unit 2 includes a plurality of first light sources 21 , a first primary lens 22 , and a first lens array 23 .

[0012] The plurality of primary light sources 21 are mounted on a substrate (not shown) with their light-emitting surfaces facing forward. The plurality of primary light sources 21 are configured so that their lighting can be individually controlled by a control unit (not shown). The primary light sources 21 may be, for example, light-emitting diodes (LEDs) or laser diodes (LDs).

[0013] In this example, the first optical unit 2 has three first light sources 21A, 21B, and 21C. The first light sources 21A, 21B, and 21C are arranged at a first interval A1 along the left-right direction. The left-right direction is an example of the first direction. Light emitted from the first light source 21 passes through the first primary lens 22 and the first lens array 23 and is emitted forward from the vehicle headlamp 1. Note that in FIG. 1 , light L1 emitted from the first light source 21A is represented by a solid line, light L2 emitted from the first light source 21B is represented by a dashed line, and light L3 emitted from the first light source 21C is represented by a dashed line. Light from the first light source 21 to the exit surface of the first primary lens 22 is not shown.

[0014] The first primary lens 22 is configured to collimate the light emitted from each of the plurality of first light sources 21. The first primary lens 22 is an example of a first optical element. As the first primary lens 22, for example, a collimating lens such as a TIR (Total Internal Reflection) lens can be used.

[0015] The first lens array 23 has a plurality of first lens elements 231. The plurality of first lens elements 231 are arranged along the arrangement direction of the plurality of first light sources 21 (the left-right direction in this example). Each first lens element 231 has a pair of incident surface 2311 and exit surface 2312. The incident surface 2311 and exit surface 2312 of each first lens element 231 are positioned opposite each other in the optical axis direction of the first lens element 231. The incident surface 2311 and exit surface 2312 of each first lens element 231 are smaller than the exit surface of the first primary lens 22. The first lens element 231 is configured so that light incident on the incident surface 2311 is refracted at the incident surface 2311, focused at a focal region of the exit surface 2312, and exits from the exit surface 2312. In FIG. 1 , the focal position of the exit surface 2312 is indicated by a two-dot chain line.

[0016] In this example, the first lens array 23 has two first lens elements 231. The two first lens elements 231 are arranged in contact with each other at a third interval B1 in the left-right direction. The multiple first lens elements 231 are integrated by, for example, molding a transparent resin material or a glass material in a mold. Alternatively, each first lens element 231 may be molded in a mold and then bonded together with an adhesive or the like to be integrated.

[0017] 2 illustrates a first light distribution pattern PH1 projected onto a virtual vertical screen by light emitted from the first optical unit 2 configured as described above. The virtual vertical screen is disposed, for example, at a position 25 m ahead of the vehicle headlight 1. In FIG. 2, H indicates the horizontal line, and V indicates a vertical line passing through the center of the illumination range of the vehicle headlight 1.

[0018] The first light distribution pattern PH1 includes light distribution areas PH1A, PH1B, and PH1C. The light distribution area PH1A is a projected image of the primary light source 21A. The light distribution area PH1B is a projected image of the primary light source 21B. The light distribution area PH1C is a projected image of the primary light source 21C. In FIG. 2 , the light distribution area PH1A is represented by a solid line, the light distribution area PH1B is represented by a dashed line, and the light distribution area PH1C is represented by a dashed-dotted line. The light distribution areas PH1A, PH1B, and PH1C are formed along the horizontal direction.

[0019] 1 , light L1 emitted from the first light source 21A and incident on the first primary lens 22 is emitted as parallel light from the first primary lens 22 and then incident on the first lens array 23. The light L1 incident on the first lens array 23 is refracted by the incident surface 2311 of the first lens element 231, condensed in a focal region of the exit surface 2312 of the first lens element 231 to which the incident surface 2311 belongs, and emitted from the exit surface 2312. Here, in this example, the first light source 21A is disposed near the optical axis (not shown) of the first primary lens 22 extending in the front-rear direction, and the first lens array 23 is disposed such that the optical axis (not shown) of the first lens element 231 is substantially parallel to the optical axis of the first primary lens 22. Therefore, light L1 emitted from first light source 21A is emitted forward from first primary lens 22, enters incident surface 2311 of first lens element 231, and is emitted forward from exit surface 2312 of first lens element 231. As a result, as illustrated in Fig. 2, light distribution area PH1A formed by light L1 emitted from first light source 21A is located on line V. Note that exit surface 2312 of first lens element 231 to which incident surface 2311 belongs is exit surface 2312 provided at a position facing incident surface 2311 in the optical axis direction of first lens element 231.

[0020] 1 , light L2 emitted from first light source 21B and incident on first primary lens 22 is emitted as parallel light from first primary lens 22 and then incident on first lens array 23. Light L2 incident on first lens array 23 is refracted by incident surface 2311 of first lens element 231, condensed in a focal region of exit surface 2312 of first lens element 231 to which incident surface 2311 belongs, and emitted from exit surface 2312. Here, in this example, first light source 21B is disposed to the left of first light source 21A. Therefore, light L2 emitted from first light source 21B is emitted obliquely in a forward right direction from first primary lens 22, enters incident surface 2311 of first lens element 231, and is emitted obliquely in a forward left direction from exit surface 2312 of first lens element 231. As a result, as illustrated in FIG. 2, a light distribution area PH1B formed by the light L2 emitted from the first light source 21B is formed to the left of the light distribution area PH1A.

[0021] 1 , light L3 emitted from first light source 21C and incident on first primary lens 22 is emitted as parallel light from first primary lens 22 and then incident on first lens array 23. Light L3 incident on first lens array 23 is refracted by incident surface 2311 of first lens element 231, condensed in a focal region of exit surface 2312 of first lens element 231 to which incident surface 2311 belongs, and emitted from exit surface 2312. Here, in this example, first light source 21C is disposed to the right of first light source 21A. Therefore, light L3 emitted from first light source 21C is emitted diagonally in a forward left direction from first primary lens 22, enters incident surface 2311 of first lens element 231, and is emitted diagonally in a forward right direction from exit surface 2312 of first lens element 231. As a result, as illustrated in FIG. 2, a light distribution area PH1C formed by the light L3 emitted from the first light source 21C is formed to the right of the light distribution area PH1A.

[0022] In this way, in the first optical unit 2, the projection angles of the light distribution regions PH1A, PH1B, and PH1C of the first light distribution pattern PH1 can be made to differ by arranging the multiple first light sources 21 at the first interval A1 and varying the emission direction of light from the first primary lens 22. As a result, the light distribution regions PH1A, PH1B, and PH1C are formed at a predetermined projection angle interval D1.

[0023] As illustrated in FIG. 1 , the second optical unit 3 includes a plurality of second light sources 31 , a second primary lens 32 , and a second lens array 33 .

[0024] The plurality of secondary light sources 31 are mounted on a substrate (not shown) with their light-emitting surfaces facing forward. The plurality of secondary light sources 31 are configured so that their lighting can be individually controlled by a control unit (not shown). The secondary light sources 31 may be, for example, LEDs or LDs.

[0025] In this example, the second optical unit 3 has two second light sources 31A and 31B. The second light sources 31A and 31B are arranged at a second interval A2 in the left-right direction. The second interval A2 is different from the first interval A1 between the first light sources 21 of the first optical unit 2. Light emitted from the second light source 31 passes through the second primary lens 32 and the second lens array 33 and is emitted forward from the vehicle headlamp 1. Note that in FIG. 1 , light L4 emitted from the second light source 31A is represented by a solid line, and light L5 emitted from the second light source 31B is represented by a dashed line. Illustration of light from the second light source 31 to the exit surface of the second primary lens 32 is omitted.

[0026] The second primary lens 32 is configured to convert the light emitted from each of the plurality of second light sources 31 into parallel light. The second primary lens 32 is an example of a second optical element. As the second primary lens 32, for example, a collimating lens such as a TIR lens can be used.

[0027] The second lens array 33 has a plurality of second lens elements 331. The plurality of second lens elements 331 are arranged along the arrangement direction of the plurality of second light sources 31 (the left-right direction in this example). The second lens elements 331 have a pair of incident surface 3311 and exit surface 3312. The incident surface 3311 and the exit surface 3312 of the second lens elements 331 are positioned opposite each other in the optical axis direction of the second lens elements 331. The incident surface 3311 and the exit surface 3312 of the second lens elements 331 are smaller than the exit surface of the second primary lens 32. The second lens elements 331 are configured so that light incident on the incident surface 3311 is refracted at the incident surface 3311, condensed at a focal region of the exit surface 3312, and exits from the exit surface 3312. Note that in FIG. 1, the focal position of the exit surface 3312 is indicated by a two-dot chain line.

[0028] In this example, the second lens array 33 has two second lens elements 331. The two second lens elements 331 are arranged in contact with each other at a fourth interval B2 along the left-right direction. The fourth interval B2 may be the same as or different from the third interval B1 between the first lens elements 231 of the first optical unit 2. The multiple second lens elements 331 are integrated by, for example, molding a transparent resin material or a glass material in a mold. Alternatively, the second lens elements 331 may be integrated by being bonded together with an adhesive or the like after being molded in a mold.

[0029] FIG. 3 illustrates a second light distribution pattern PH2 projected onto a virtual vertical screen by light emitted from the second optical unit 3 configured as described above.

[0030] The second light distribution pattern PH2 includes light distribution regions PH2A and PH2B. The light distribution region PH2A is a projected image of the secondary light source 31A. The light distribution region PH2B is a projected image of the secondary light source 31B. In Fig. 3, the light distribution region PH2A is represented by a solid line, and the light distribution region PH2B is represented by a dashed line. The light distribution regions PH2A and PH2B are formed along the horizontal direction.

[0031] 1 , light L4 emitted from second light source 31A and incident on second primary lens 32 is emitted as parallel light from second primary lens 32 and then incident on second lens array 33. Light L4 incident on second lens array 33 is refracted by incident surface 3311 of second lens element 331, condensed in a focal region of exit surface 3312 of second lens element 331 to which incident surface 3311 belongs, and emitted from exit surface 3312. Here, in this example, second light source 31A is disposed to the left of the optical axis (not shown) of second primary lens 32 extending in the front-rear direction, and second lens array 33 is disposed such that the optical axis (not shown) of second lens element 331 is substantially parallel to the optical axis of second primary lens 32. Therefore, light L4 emitted from second light source 31A is emitted obliquely in a front right direction from second primary lens 32, enters incident surface 3311 of second lens element 331, and is emitted obliquely in a front left direction from exit surface 3312 of second lens element 331. As a result, as illustrated in Figure 3, light distribution area PH2A formed by light L4 emitted from second light source 31A is formed to the left of line V-V. Note that exit surface 3312 of second lens element 331 to which incident surface 3311 belongs is exit surface 3312 provided at a position facing incident surface 3311 in the optical axis direction of second lens element 331.

[0032] 1 , light L5 emitted from the second light source 31B and incident on the second primary lens 32 is emitted as parallel light from the second primary lens 32 and then incident on the second lens array 33. The light L5 incident on the second lens array 33 is refracted by the incident surface 3311 of the second lens element 331, condensed in a focal region of the exit surface 3312 of the second lens element 331 to which the incident surface 3311 belongs, and then emitted from the exit surface 3312. Here, in this example, the second light source 31B is disposed to the right of the optical axis of the second primary lens 32 extending in the front-to-rear direction. Therefore, the light L5 emitted from the second light source 31B is emitted diagonally in the left-front direction from the second primary lens 32, enters the incident surface 3311 of the second lens element 331, and is emitted diagonally in the right-front direction from the exit surface 3312 of the second lens element 331. As a result, as illustrated in FIG. 3, a light distribution area PH2B formed by the light L5 emitted from the second light source 31B is formed on the right side of the line VV.

[0033] In this way, in the second optical unit 3, the projection angles of the light distribution areas PH2A and PH2B of the second light distribution pattern PH2 can be made different by arranging the multiple second light sources 31 at the second interval A2 and varying the emission direction of light from the second primary lens 32. As a result, the light distribution areas PH2A and PH2B are formed at a predetermined projection angle interval D2.

[0034] Fig. 4 illustrates a high-beam light distribution pattern PH projected onto a virtual vertical screen by light emitted from the vehicle headlamp 1. The high-beam light distribution pattern PH is a light distribution pattern that combines the first light distribution pattern PH1 shown in Fig. 2 and the second light distribution pattern PH2 shown in Fig. 3. In Fig. 4, the first light distribution pattern PH1 and the second light distribution pattern PH2 are represented using different hatching.

[0035] ADB light distribution can be performed by individually controlling the on / off of the first light sources 21A, 21B, and 21C that form the light distribution areas PH1A, PH1B, and PH1C of the first light distribution pattern PH1 and the second light sources 31A and 31B that form the light distribution areas PH2A and PH2B of the second light distribution pattern PH2 using a control unit not shown.

[0036] The vehicle headlamp 1 is configured so that the projection angles of the light distribution regions PH1A, PH1B, and PH1C of the first light distribution pattern PH1 are different from the projection angles of the light distribution regions PH2A and PH2B of the second light distribution pattern PH2. More specifically, the vehicle headlamp 1 is configured so that the light distribution region PH2A of the second light distribution pattern PH2 is projected between the light distribution regions PH1A and PH1B of the first light distribution pattern PH1, and the light distribution region PH2B of the second light distribution pattern PH2 is projected between the light distribution regions PH1A and PH1C of the first light distribution pattern PH1.

[0037] The projection angle interval of the projected image (light distribution area) of the light source depends on the arrangement interval of the light sources. Specifically, the greater the arrangement interval of the light sources, the greater the projection angle interval of the projected image of the light source.

[0038] In the vehicle headlamp 1 according to the present disclosure, the first spacing A1 between the first light sources 21 of the first optical unit 2 and the second spacing A2 between the second light sources 31 of the second optical unit 3 are configured to be different from each other, so that the projection angle spacing of the projected images of the light sources is different, and the projection angles of the light distribution regions PH1A, PH1B, and PH1C of the first light distribution pattern PH1 can be made different from the projection angles of the light distribution regions PH2A and PH2B of the second light distribution pattern PH2. This makes it possible to form a high beam light distribution pattern PH with little change in brightness.

[0039] In addition to the spacing between the light sources, the vehicle headlamp 1 may be configured such that other optical designs of the primary lens and lens elements differ between the first optical unit 2 and the second optical unit 3 .

[0040] For example, the vehicle headlamp 1 may be configured such that the ratio of the incident thickness to the exit thickness of the first lens element 231 of the first optical unit 2 is different from the ratio of the incident thickness to the exit thickness of the second lens element 331 of the second optical unit 3. Here, the incident thickness is the thickness from the incident surface to the focal position of the exit surface. The exit thickness is the thickness from the focal position of the exit surface to the exit surface.

[0041] 5 and 6 are diagrams illustrating the relationship between the ratio of the incident thickness to the exit thickness of the lens elements of the lens array and the projection angle interval of the projected image of the light source. Fig. 5 shows two optical units 11 and 12 having different ratios of the incident thickness to the exit thickness of the lens elements of the lens array. Fig. 6 shows a light distribution pattern PH11 formed by light emitted from optical unit 11 and a light distribution pattern PH12 formed by light emitted from optical unit 14. Note that Fig. 5 shows only a portion of the light beams L11 and L12 emitted from the light source. The focal position of the exit surface of the lens array is indicated by a two-dot chain line.

[0042] 5, optical unit 11 includes a plurality of light sources 111, a primary lens 112, and a lens array 113 having a plurality of lens elements. Optical unit 12 includes a plurality of light sources 121, a primary lens 122, and a lens array 123 having a plurality of lens elements. Optical unit 11 and optical unit 12 have the same configuration except that the ratio of the entrance thickness to the exit thickness of the lens elements of the lens array is different.

[0043] When the ratio of the incident thickness T1 to the exit thickness T2 of the lens elements of lens array 113 of optical unit 11 (incident thickness T1 / exit thickness T2) is greater than the ratio of the incident thickness T3 to the exit thickness T4 of the lens elements of lens array 123 of optical unit 12 (incident thickness T3 / exit thickness T4), as illustrated in Figure 6, the size S11 of the projected image of the light source in the light distribution pattern PH11 formed by optical unit 11 becomes smaller than the size S12 of the projected image of the light source in the light distribution pattern PH12 formed by optical unit 12.

[0044] In other words, the size of the projected image of the light source depends on the ratio between the incident thickness and the exit thickness of the lens elements of the lens array, and the larger the ratio between the incident thickness and the exit thickness of the lens elements of the lens array (incident thickness / exit thickness), the smaller the size of the projected image of the light source.

[0045] Therefore, since the ratio of the incident thickness to the exit thickness of the lens elements of the lens array is different between the first optical unit 2 and the second optical unit 3, the projection size S1 of the light distribution areas PH1A, PH1B, PH1C of the first light distribution pattern PH1 can be made different from the projection size S2 of the light distribution areas PH2A, PH2B of the second light distribution pattern PH2.

[0046] In addition, the vehicle headlamp 1 may be configured so that the radius of curvature of the exit surface 2312 of the first lens element 231 of the first optical unit 2 is different from the radius of curvature of the exit surface 3312 of the second lens element 331 of the second optical unit 3.

[0047] The size of the projected image of the light source depends on the radius of curvature of the exit surface of the lens element. Specifically, the larger the radius of curvature of the exit surface of the lens element of the optical unit, the smaller the size of the projected image of the light source in the light distribution pattern formed by the optical unit.

[0048] Therefore, by making the radius of curvature of the exit surface 2312 of the first lens element 231 different from the radius of curvature of the exit surface 3312 of the second lens element 331, the projection size S1 of the light distribution areas PH1A, PH1B, PH1C of the first light distribution pattern PH1 can be made different from the projection size S2 of the light distribution areas PH2A, PH2B of the second light distribution pattern PH2.

[0049] Furthermore, the vehicle headlamp 1 may be configured so that the F-number of the first primary lens 22 is different from the F-number of the second primary lens 32 .

[0050] 7 and 8 are diagrams illustrating the relationship between the F-number of the primary lens and the projection angle interval and size of the projected image of the light source. Fig. 7 shows two optical units 13 and 14 having different F-numbers of the primary lenses. Fig. 8 shows a light distribution pattern PH13 formed by light emitted from optical unit 13 and a light distribution pattern PH14 formed by light emitted from optical unit 14. Note that Fig. 7 shows only a portion of the light L13 and L14 emitted from the light source. The focal position of the exit surface of the lens array is indicated by a two-dot chain line.

[0051] 7, optical unit 13 includes a plurality of light sources 131, a primary lens 132, and a lens array 133 having a plurality of lens elements. Optical unit 14 includes a plurality of light sources 141, a primary lens 142, and a lens array 143 having a plurality of lens elements. Optical unit 13 and optical unit 14 have the same configuration except that the F-numbers of the primary lenses are different.

[0052] When the F-number of primary lens 132 of optical unit 13 is larger than the F-number of primary lens 142 of optical unit 14, the parallelism of the light rays emitted from primary lens 132 is higher than the parallelism of the light rays emitted from primary lens 142. In other words, the light emitted from primary lens 142 travels more widely than the light emitted from primary lens 132. As a result, as illustrated in Fig. 8 , the projection angle interval D13 and size S13 of the projected image of the light source in light distribution pattern PH13 formed by optical unit 13 are smaller than the projection angle interval D14 and size S14 of the projected image of the light source in light distribution pattern PH14 formed by optical unit 14.

[0053] That is, the projection angle interval and size of the projected image of the light source depend on the F-number of the primary lens, and the larger the F-number of the primary lens, the smaller the projection angle interval and size of the projected image of the light source.

[0054] Therefore, by having different F-numbers of the primary lenses between the first optical unit 2 and the second optical unit 3, the projection angle interval D1 and projection size S1 of the light distribution areas PH1A, PH1B, and PH1C of the first light distribution pattern PH1 can be made different from the projection angle interval D2 and projection size S2 of the light distribution areas PH2A and PH2B of the second light distribution pattern PH2.

[0055] In addition to the spacing between the light sources, the vehicle headlamp 1 may be configured so that several optical designs, including the ratio between the incident thickness and the exit thickness of the lens elements of the lens array, the radius of curvature of the exit surface of the lens element, and the F-number of the primary lens, are different between the first optical unit 2 and the second optical unit 3.

[0056] (Variation 1) In the vehicle headlamp 1 according to the present disclosure, the entrance surface and exit surface of each of the plurality of lens elements constituting the lens array are smaller than the exit surface of the primary lens, and the plurality of lens elements are integrated, so that light can be incident from adjacent lens elements. Therefore, the vehicle headlamp 1 has a structure in which crosstalk is easily generated in part of the light incident on the lens array.

[0057] Here, crosstalk means that light incident on the entrance surface of a lens element is incident on the exit surface of a lens element other than the lens element to which the entrance surface belongs, and exits from the exit surface.

[0058] The vehicle headlamp 1 may be configured to include an optical unit that utilizes such crosstalk.

[0059] 9 is a plan view illustrating the configuration of the third optical unit 4 utilizing crosstalk. As illustrated in FIG. 9, the third optical unit 4 includes a plurality of third light sources 41, a third primary lens 42, and a third lens array 43.

[0060] The third light sources 41 are mounted on a substrate (not shown) with their emission surfaces facing forward. The third light sources 41 are configured so that their lighting can be individually controlled by a control unit (not shown). The third light sources 41 may be, for example, LEDs or LDs.

[0061] In this example, the third optical unit 4 has two third light sources 41A and 41B. The third light sources 41A and 41B are arranged at a fifth interval A3 in the left-right direction. The fifth interval A3 is wider than the second interval A2. Light emitted from the third light source 41 passes through the third primary lens 42 and the third lens array 43 and is emitted forward from the vehicle headlamp 1. Note that in FIG. 9 , light L6 emitted from the third light source 41A is represented by a solid line, and light L7 emitted from the third light source 41B is represented by a dashed line. Light from the third light source 41 to the exit surface of the third primary lens 42 is not shown.

[0062] The third primary lens 42 is configured to convert the light emitted from each of the plurality of third light sources 41 into parallel light. As the third primary lens 42, for example, a collimating lens such as a TIR lens can be used.

[0063] The third lens array 43 has a plurality of third lens elements 431. The plurality of third lens elements 431 are arranged along the arrangement direction of the plurality of third light sources 41 (the left-right direction in this example). The third lens elements 431 have a pair of incident surface 4311 and exit surface 4312. The incident surface 4311 and the exit surface 4312 of the third lens elements 431 are positioned opposite each other in the optical axis direction of the third lens elements 431. The incident surface 4311 and the exit surface 4312 of the third lens elements 431 are smaller than the exit surface of the third primary lens 42. The third lens elements 431 are configured so that light incident on the incident surface 4311 is refracted at the incident surface 4311, condensed in a focal region of the exit surface 4312, and exits from the exit surface 4312.

[0064] In this example, the third lens array 43 has four third lens elements 431. The four third lens elements 431 are arranged in contact with one another at a sixth interval B3 along the left-right direction. The sixth interval B3 is narrower than the fourth interval B2. The multiple third lens elements 431 are integrated by, for example, molding a transparent resin material or a glass material in a mold. Alternatively, the third lens elements 431 may be integrated by being bonded together with an adhesive or the like after being molded in a mold.

[0065] FIG. 10 illustrates a third light distribution pattern PH3 projected onto a virtual vertical screen by light emitted from the third optical unit 4 configured as described above.

[0066] The third light distribution pattern PH3 includes light distribution regions PH3A and PH3B. The light distribution region PH3A is a projected image of the third light source 41A. The light distribution region PH3B is a projected image of the third light source 41B. In Fig. 10, the light distribution region PH3A is represented by a solid line, and the light distribution region PH3B is represented by a dashed line. The light distribution regions PH3A and PH3B are formed along the horizontal direction.

[0067] 9 , light L6 emitted from the third light source 41A and incident on the third primary lens 42 is emitted as parallel light from the third primary lens 42 and then incident on the third lens array 43. The light L6 incident on the third lens array 43 is refracted by the incident surface 3311 of the third lens element 431, condensed in a focal region of the exit surface 3312, and emitted from the exit surface 3312. Here, in this example, the third light source 41A is disposed to the left of the optical axis (not shown) of the third primary lens 42 that extends in the front-to-rear direction, and the third lens array 43 is disposed such that the optical axis (not shown) of the third lens element 431 is substantially parallel to the optical axis of the third primary lens 42.

[0068] Therefore, light L6 emitted from third light source 41A is emitted obliquely in the front right direction from third primary lens 42 and enters third lens element 431. A portion of light L6 that has entered incident surface 4311 of third lens element 431 is emitted obliquely in the front right direction from exit surface 4312 of third lens element 431 to which incident surface 4311 belongs.

[0069] Furthermore, a portion of light L6 incident on incident surface 4311 of third lens element 431 is emitted diagonally in a right-front direction from exit surface 4312 of a third lens element 431 that is adjacent to or further away from the third lens element 431 to which incident surface 4311 belongs. That is, crosstalk occurs in the portion of light L6 that is incident on incident surface 4311 of third lens element 431. As a result, as illustrated in Fig. 10 , light distribution area PH3A formed by light L6 emitted from third light source 41A is formed to the right of line V-V, and further to the right of light distribution area PH2B formed by light L2 emitted from first light source 21B of first optical unit 2 shown in Fig. 2.

[0070] 9 , light L7 emitted from the third light source 41B and incident on the third primary lens 42 is emitted as parallel light from the third primary lens 42 and incident on the third lens array 43. The light L7 incident on the third lens array 43 is refracted by the incident surface 4311 of the third lens element 431, condensed in a focal region of the exit surface 4312, and emitted from the exit surface 4312. Here, in this example, the third light source 41B is disposed to the right of the optical axis of the third primary lens 42 extending in the front-to-rear direction.

[0071] Therefore, light L7 emitted from third light source 41B is emitted obliquely in the front left direction from third primary lens 42 and enters third lens element 431. A portion of light L7 that has entered incident surface 4311 of third lens element 431 is emitted obliquely in the front left direction from exit surface 4312 of third lens element 431 to which incident surface 4311 belongs.

[0072] Furthermore, a portion of light L7 incident on incident surface 4311 of third lens element 431 is emitted diagonally in a left-front direction from exit surface 4312 of a third lens element 431 that is adjacent to or further away from the third lens element 431 to which incident surface 4311 belongs. That is, crosstalk occurs in the portion of light L7 that is incident on incident surface 4311 of third lens element 431. As a result, as illustrated in Fig. 10 , light distribution area PH3B formed by light L7 emitted from third light source 41B is formed to the left of line V-V and further to the left of light distribution area PH2C formed by light L3 emitted from first light source 21C of first optical unit 2 shown in Fig. 2.

[0073] In this way, in the third optical unit 4, by arranging multiple third light sources 41 at a fifth interval A3 and changing the direction of light emission from the third primary lens 42, the projection angles of the light distribution areas PH3A and PH3B of the third light distribution pattern PH3 can be changed.

[0074] Furthermore, the arrangement interval (fifth interval A3) of the multiple third light sources 41 and the arrangement interval (sixth interval B3) of the third lens elements 431 are adjusted to generate crosstalk within the third lens array 43. Specifically, in this example, the arrangement interval (fifth interval A3) of the multiple third light sources 41 is larger than the second interval A2 of the second optical unit 3, and the arrangement interval (sixth interval B3) of the third lens elements 431 is smaller than the fourth interval B2 of the second lens elements 331 of the second optical unit 3. This causes crosstalk to occur, and the light distribution areas PH3A and PH3B are formed at a predetermined projection angle interval D3 that is wider than the projection angle interval D2 of the light distribution areas PH2A and PH2B formed by the second optical unit 3. This allows the projection angles of the light distribution areas PH3A and PH3B to be larger than the projection angles of the light distribution areas PH2A and PH2B.

[0075] Fig. 11 illustrates a high-beam light distribution pattern PH projected onto a virtual vertical screen by light emitted from the vehicle headlamp 1. The high-beam light distribution pattern PH is a light distribution pattern that combines the first light distribution pattern PH1 shown in Fig. 2, the second light distribution pattern PH2 shown in Fig. 3, and the third light distribution pattern PH3 shown in Fig. 10. In Fig. 11, the first light distribution pattern PH1, the second light distribution pattern PH2, and the third light distribution pattern PH3 are represented using different hatching.

[0076] A control unit (not shown) can individually control the on / off of first light sources 21A, 21B, and 21C that form light distribution areas PH1A, PH1B, and PH1C of the first light distribution pattern PH1, second light sources 31A and 31B that form light distribution areas PH2A and PH2B of the second light distribution pattern PH2, and third light sources 41A and 41B that form light distribution areas PH3A and PH3B of the third light distribution pattern PH3, thereby enabling ADB light distribution.

[0077] The projection angles of the light distribution areas PH3A and PH3B formed by utilizing crosstalk depend on the arrangement interval (sixth interval B3) of the third lens elements 431 of the third lens array 43.

[0078] 12 and 13 are diagrams illustrating the relationship between the arrangement spacing of lens elements and the projection angle spacing of the projected images of the light sources. Fig. 12 shows two optical units 15 and 16 in which the arrangement spacing of the light sources is different. Fig. 13 shows a light distribution pattern PH15 formed by light emitted from optical unit 15 and a light distribution pattern PH16 formed by light emitted from optical unit 16. Note that Fig. 12 shows only a portion of the light L15 and L16 emitted from the light sources. The focal position of the exit surface of the lens array is indicated by a two-dot chain line.

[0079] As illustrated in Fig. 12, optical unit 15 includes a plurality of light sources 151, a primary lens 152, and a lens array 153 having a plurality of lens elements. The plurality of lens elements are arranged at a predetermined arrangement interval B15. Optical unit 16 includes a plurality of light sources 161, a primary lens 162, and a lens array 163 having a plurality of lens elements. The plurality of lens elements are arranged at a predetermined arrangement interval B16. Optical unit 15 and optical unit 16 have the same configuration except for the arrangement interval of the lens elements.

[0080] When the arrangement spacing B15 of the lens elements of lens array 153 of optical unit 15 is larger than the arrangement spacing B16 of the lens elements of lens array 163 of optical unit 16, as illustrated in Figure 13, the projection angle spacing D15 of the projected image of the light source in the light distribution pattern PH15 formed by optical unit 15 becomes larger than the projection angle spacing D16 of the projected image of the light source in the light distribution pattern PH16 formed by optical unit 16.

[0081] In other words, in an optical unit that generates crosstalk within a lens array, the projection angle interval of the projected image of the light source depends on the arrangement interval of the lens elements of the lens array, and the greater the arrangement interval of the lens elements of the lens array, the greater the projection angle interval of the projected image of the light source.

[0082] Therefore, by adjusting the arrangement interval of the third lens elements 431 in the third optical unit 4, the projection angles of the light distribution areas PH3A and PH3B utilizing the crosstalked light can be controlled.

[0083] In the above-described embodiment and modified example 1, the second optical unit 3 may be configured to have a structure that is prone to generating crosstalk, similar to the third optical unit 4 .

[0084] (Variation 2) In the vehicle headlamp 1 according to this embodiment, the lens elements of the lens array are configured to refract light incident on the incident surface at the incident surface and collect the light in a focal region of the exit surface. However, the lens elements of the lens array may be configured to reflect light incident on the incident surface at the reflective surface, collect the light in a focal region of the exit surface, and emit the light from the exit surface.

[0085] Fig. 14 is a plan view illustrating the configuration of the fourth optical unit 5 having a reflecting surface, and Fig. 15 is a vertical cross-sectional view illustrating the configuration of the fourth optical unit 5.

[0086] The fourth optical unit 5 includes a plurality of fourth light sources 51 , a fourth primary lens 52 , and a fourth lens array 53 .

[0087] The fourth light sources 51 are mounted on a substrate (not shown) facing upward. The fourth light sources 51 are configured so that their lighting can be individually controlled by a control unit (not shown). The fourth light sources 51 may be, for example, LEDs or LDs.

[0088] In this example, the fourth optical unit 5 has three fourth light sources 51A, 51B, and 51C. The fourth light sources 51A, 51B, and 51C are arranged at a seventh interval A4 in the left-right direction. Light emitted from the fourth light source 51 passes through the fourth primary lens 52 and the fourth lens array 53, and is emitted forward of the vehicle headlamp 1.

[0089] The fourth primary lens 52 is configured to convert the light emitted from each of the plurality of fourth light sources 51 into parallel light. As the fourth primary lens 52, for example, a collimating lens such as a TIR lens can be used.

[0090] The fourth lens array 53 has a plurality of fourth lens elements 531. The plurality of fourth lens elements 531 are arranged along the arrangement direction of the plurality of fourth light sources 51 (the left-right direction in this example). The fourth lens elements 531 have an incident surface 5311, an exit surface 5312, and a reflecting surface 5313. The fourth lens elements 531 are configured so that light incident on the incident surface 5311 is reflected by the reflecting surface 5313, condensed in a focal region of the exit surface 5312, and exits from the exit surface 5312. Note that in FIG. 14 , light L8 emitted from the fourth light source 51A and reflected by the reflecting surface 5313 is represented by a solid line, light L9 emitted from the fourth light source 51B and reflected by the reflecting surface 5313 is represented by a dashed line, and light L10 emitted from the fourth light source 51C and reflected by the reflecting surface 5313 is represented by a dashed line.

[0091] In this example, the fourth lens array 53 has three fourth lens elements 531. The three fourth lens elements 531 are arranged in contact with one another at an eighth interval B4 in the left-right direction. The multiple fourth lens elements 531 are integrated by, for example, molding a transparent resin material or a glass material in a mold. Alternatively, the fourth lens elements 531 may be integrated by being bonded together with an adhesive or the like after being molded in a mold.

[0092] As illustrated in Figure 15, light L8, L9, and L10 emitted from the fourth light sources 51A, 51B, and 51C and incident on the fourth primary lens 52 are emitted as parallel light from the fourth primary lens 52 and incident on the fourth lens array 53.

[0093] 14 and 15 , light L8 incident on the fourth lens element 531 of the fourth lens array 53 is reflected by the reflecting surface 5313, condensed in a focal region of the exit surface 5312, and emitted from the exit surface 5312. Here, in this example, light L8 emitted from the fourth light source 51A is emitted upward from the fourth primary lens 52, enters the entrance surface 5311 of the fourth lens element 531, is reflected by the reflecting surface 5313 of the first lens element 231 toward the exit surface 5312 of the first lens element 231, and is emitted forward from the exit surface 5312. Since the fourth light source 51A is positioned near the optical axis (not shown) of the fourth primary lens 52 extending in the vertical direction, the light distribution area formed by the light L8 emitted from the fourth light source 51A is formed on the V line of the virtual vertical screen, similar to the light distribution area PH2A formed by the light L1 emitted from the first light source 21A of the first optical unit 2 illustrated in Figure 2.

[0094] Furthermore, light L9 incident on the fourth lens element 531 of the fourth lens array 53 is reflected by the reflecting surface 5313, condensed in a focal region of the exit surface 5312, and emitted from the exit surface 5312. In this example, the fourth light source 51B is disposed to the left of the optical axis (not shown) of the fourth primary lens 52 extending in the up-down direction, and therefore light L9 emitted from the fourth light source 51B is emitted obliquely in an upper-left direction from the fourth primary lens 52, enters the incident surface 5311 of the fourth lens element 531, is reflected by the reflecting surface 5313 of the first lens element 231 toward the exit surface 5312 of the first lens element 231, and is emitted obliquely in a front-left direction from the exit surface 5312. As a result, similar to the light distribution area PH2B formed by the light L2 emitted from the first light source 21B of the first optical unit 2 illustrated in Figure 2, the light distribution area formed by the light L9 emitted from the fourth light source 51B is formed to the left of the V line of the virtual vertical screen.

[0095] Furthermore, light L10 incident on the fourth lens elements 531 of the fourth lens array 53 is reflected by the reflecting surface 5313, condensed in a focal region of the exit surface 5312, and emitted from the exit surface 5312. In this example, the fourth light source 51C is disposed to the right of the optical axis (not shown) of the fourth primary lens 52 extending in the up-down direction, and therefore light L10 emitted from the fourth light source 51C is emitted diagonally in the upper right direction from the fourth primary lens 52, enters the incident surface 5311 of the fourth lens element 531, is reflected by the reflecting surface 5313 of the first lens element 231 toward the exit surface 5312 of the first lens element 231, and is emitted diagonally in the front right direction from the exit surface 5312. As a result, similar to the light distribution area PH2C formed by the light L3 emitted from the first light source 21C of the first optical unit 2 illustrated in Figure 2, the light distribution area formed by the light L10 emitted from the fourth light source 51C is formed to the right of the V line of the virtual vertical screen.

[0096] In this way, in the fourth optical unit 5, by arranging multiple fourth light sources 51 at a seventh interval A4 and changing the direction of light emission from the fourth primary lens 52, the projection angle of each light distribution area of ​​the light distribution pattern can be changed.

[0097] Therefore, even in a vehicle headlamp 1 that includes multiple fourth optical units 5 with different light source spacings instead of the first optical unit 2, the second optical unit 3, and the third optical unit 4, it is possible to form a high beam distribution pattern PH that has an ADB light distribution function as exemplified in Figures 4 and 11.

[0098] The present invention is not limited to the above-described embodiments and can be freely modified, improved, etc. The material, shape, dimensions, numerical values, form, number, location, etc. of each component in the above-described embodiments are arbitrary and not limited as long as they can achieve the present invention.

[0099] In the above-described embodiments and modifications, the number of light sources, the number of lens elements in the lens array, or the number of optical units is not limited to the numbers shown in the figures.

[0100] In the above embodiments and variants, the lens array of each optical unit has a configuration in which multiple lens elements are arranged in the left-right direction, but it may also have a configuration in which multiple lens elements are arranged in the left-right direction and stacked in the up-down direction.

[0101] In the above-described embodiment and modified examples, the projection angle of each light distribution region of the light distribution pattern formed by each optical unit is adjusted by varying the arrangement interval of the light sources between the optical units in the vehicle headlamp 1. However, even if the arrangement interval of the light sources is the same between the optical units in the vehicle headlamp 1, it is also possible to adjust the projection angle of each light distribution region of the light distribution pattern formed by each optical unit by varying the position of the light source in the left-right direction with respect to the optical axis of the lens array.

[0102] Item 1: A vehicle headlamp comprising: a first optical unit having: a plurality of first light sources whose lighting can be controlled individually; a first optical element that converts light from each of the plurality of first light sources into parallel light; and a first lens array having a plurality of first lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light that has been incident on the entrance surface from the first optical elements from the exit surface; and a second optical unit having: a plurality of second light sources whose lighting can be controlled individually; a second optical element that converts light from each of the plurality of second light sources into parallel light; and a second lens array having a plurality of second lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light that has been incident on the entrance surface from the second optical elements from the exit surface; wherein the plurality of first light sources are arranged at a first interval along a first direction and the plurality of second light sources are arranged at a second interval along the first direction, and the first interval and the second interval are different from each other. Item 2: The vehicle headlamp according to Item 1, wherein the second optical unit is configured so that at least a portion of light incident from an incident surface of a second lens element of the second lens array exits from an exit surface of a second lens element different from the second lens element having the incident surface. Item 3: The vehicle headlamp according to Item 2, wherein the plurality of first lens elements are arranged at a third interval along the first direction and the plurality of second lens elements are arranged at a fourth interval along the first direction, and the third interval is different from the fourth interval. Item 4: The vehicle headlamp according to any one of Items 1 to 3, wherein a radius of curvature of the exit surface of the first lens element is different from a radius of curvature of the exit surface of the second lens element. Item 5: The vehicle headlamp according to any one of items 1 to 4, wherein a ratio of a thickness of the first lens element from the incident surface to a focal position of the exit surface to a thickness from the focal position to the exit surface is different from a ratio of a thickness of the second lens element from the incident surface to a focal position of the exit surface to a thickness from the focal position to the exit surface. Item 6: The vehicle headlamp according to any one of items 1 to 5, wherein the first optical element is a first lens, the second optical element is a second lens, and an F-number of the first lens is different from an F-number of the second lens.Item 7: A first optical unit having: a plurality of first light sources whose lighting can be controlled individually; a first optical element that converts light from each of the plurality of first light sources into parallel light; and a first lens array having a plurality of first lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light incident on the entrance surface from the first optical elements from the exit surface; and a second optical unit having: a plurality of second light sources whose lighting can be controlled individually; a second optical element that converts light from each of the plurality of second light sources into parallel light; and a second lens array having a plurality of second lens elements each having a pair of entrance surface and exit surface, and emitting the parallel light incident on the entrance surface from the second optical elements from the exit surface; wherein the plurality of first light sources are arranged at a first interval along a first direction and the plurality of second light sources are arranged at a second interval along the first direction, the first interval and the second interval are the same, A vehicle headlamp, wherein positions of the plurality of first light sources relative to the optical axis of the first lens array in the first direction are different from positions of the plurality of second light sources relative to the optical axis of the second lens array in the first direction.

[0103] This application is based on Japanese Patent Application No. 2023-220815, filed on December 27, 2023, the contents of which are incorporated herein by reference.

Claims

1. A first optical unit having: a plurality of first light sources that can be individually controlled for lighting; a first optical element that makes the light from each of the plurality of first light sources into parallel light; a plurality of first lens elements each having a pair of incident surfaces and exit surfaces, and a first lens array that emits the parallel light incident on the incident surfaces from the first optical element from the exit surfaces; a plurality of second light sources that can be individually controlled for lighting; a second optical element that makes the light from each of the plurality of second light sources into parallel light; a plurality of second lens elements each having a pair of incident surfaces and exit surfaces, and a second lens array that emits the parallel light incident on the incident surfaces from the second optical element from the exit surfaces; wherein the plurality of first light sources are arranged at a first interval along a first direction, the plurality of second light sources are arranged at a second interval along the first direction, and the first interval and the second interval are different from each other, a vehicle headlamp.

2. The vehicle headlamp according to claim 1, wherein the second optical unit is configured such that at least a part of the light incident from the incident surface of a certain second lens element of the second lens array exits from the exit surface of a second lens element different from the second lens element having the incident surface on which the light is incident.

3. The vehicle headlamp according to claim 2, wherein the plurality of first lens elements are arranged at a third interval along the first direction, the plurality of second lens elements are arranged at a fourth interval along the first direction, and the third interval is different from the fourth interval.

4. The vehicle headlamp according to claim 1 or claim 2, wherein the radius of curvature of the exit surface of the first lens element is different from the radius of curvature of the exit surface of the second lens element.

5. The vehicle headlamp according to claim 1 or claim 2, wherein the ratio of the thickness from the incident surface to the focal position of the exit surface of the first lens element to the thickness from the focal position to the exit surface of the first lens element is different from the ratio of the thickness from the incident surface to the focal position of the exit surface of the second lens element to the thickness from the focal position to the exit surface of the second lens element.

6. The vehicle headlamp according to claim 1 or claim 2, wherein the first optical element is a first lens, the second optical element is a second lens, and the F value of the first lens is different from the F value of the second lens.

7. A first optical unit having: a plurality of first light sources capable of being individually controlled for lighting; a first optical element that makes the light from each of the plurality of first light sources into parallel light; a plurality of first lens elements each having a pair of incident surfaces and exit surfaces, and a first lens array that emits the parallel light incident on the incident surfaces from the first optical element from the exit surfaces; a second optical unit having: a plurality of second light sources capable of being individually controlled for lighting; a second optical element that makes the light from each of the plurality of second light sources into parallel light; a plurality of second lens elements each having a pair of incident surfaces and exit surfaces, and a second lens array that emits the parallel light incident on the incident surfaces from the second optical element from the exit surfaces; wherein the plurality of first light sources are arranged at a first interval along a first direction, the plurality of second light sources are arranged at a second interval along the first direction, the first interval and the second interval are the same, and the positions of the plurality of first light sources with respect to the optical axis of the first lens array in the first direction are different from the positions of the plurality of second light sources with respect to the optical axis of the second lens array in the first direction. A vehicle headlamp.

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