Headlight device

Abstract

A headlight device (3) comprises: a light source unit (30) having a plurality of light sources (31, 32); a single optical unit (300) which has an incidence surface (310) and an emission surface (320), and in which a plurality of light beams emitted respectively from light-emission surfaces (31a, 32a) of the plurality of light sources (31, 32) enter from the incidence surface (310) and the plurality of incident light beams are projected as a plurality of projected light beams (L31, L32) from the emission surface (320) such that a light distribution is formed by the plurality of projected light beams (L31, L32); and a structure (340) that limits the size of the luminous flux diameter of the plurality of light beams emitted respectively from the light-emission surfaces (31a, 32a) of the plurality of light sources (31, 32).

Description

[Technical field]

[0001] The present disclosure relates to a headlamp device. [Background technology]

[0002] A headlamp device has been proposed that has multiple light sources (e.g., light-emitting diodes (LEDs)) and multiple lenses as optical components, segments the light distribution (i.e., configures the light irradiation range with multiple segments), and controls the lighting of multiple light sources corresponding to the multiple segments individually (see, for example, Patent Document 1). This headlamp device has a function of preventing dazzling of the driver of the vehicle by excluding areas where vehicles such as a preceding vehicle or an oncoming vehicle are present from the irradiation range. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-114425 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned headlight device is composed of multiple light sources and multiple lenses, and has a large number of optical components, which makes it difficult to obtain the desired light distribution because errors (particularly assembly errors) are likely to be large (i.e., positional accuracy is likely to be low).

[0005] The present disclosure has been made to solve the above-mentioned problems, and has an object to provide a headlamp device that can obtain a desired light distribution. [Means for solving the problem]

[0006] The headlight device according to the present disclosure is characterized in that it comprises a light source unit having a plurality of light sources, a single optical unit having an entrance surface and an exit surface, in which a plurality of light beams emitted from the light-emitting surfaces of the plurality of light sources are incident on the entrance surface and the incident plurality of light beams are projected from the exit surface as a plurality of projected light beams to form a light distribution with the plurality of projected light beams, and a structure that limits the size of the luminous flux diameter of the plurality of light beams emitted from the light-emitting surfaces of the plurality of light sources. Effect of the Invention

[0007] According to the present disclosure, a desired light distribution can be obtained. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a schematic configuration of a headlamp device according to a first embodiment. [Diagram 2] 2 is a side view showing a schematic configuration of the headlamp device of FIG. 1. [Diagram 3] FIG. 3A is a front view showing a light source unit of the headlamp device of FIGS. 1 and 2, and FIGS. 3B and 3C are diagrams showing an example of an illumination range divided into four segments. FIG. [Figure 4] FIG. 11 is a perspective view showing a schematic configuration of a headlamp device according to a second embodiment. [Diagram 5] 5 is a side view showing a schematic configuration of the main components of the headlamp device shown in FIG. 4. [Figure 6] FIG. 6(A) is a front view showing the light source unit of the headlamp device of FIGS. 4 and 5, and (B) and (C) are diagrams showing an example of an illumination range divided into four segments. FIG. [Figure 7] FIG. 11 is a perspective view showing a schematic configuration of a headlamp device according to a third embodiment. [Figure 8] 8 is a side view showing a schematic view of the main configuration of the headlamp device in FIG. 7. [Figure 9] FIG. 9(A) is a front view showing the light source unit of the headlamp device of FIGS. 7 and 8, and (B) and (C) are diagrams showing an example of an illumination range divided into two segments. FIG. [Figure 10] FIG. 11 is a perspective view showing a schematic configuration of a headlamp device according to a fourth embodiment. [Figure 11] 11 is a side view showing a schematic view of the main configuration of the headlamp device shown in FIG. 10. [Figure 12] FIG. 12(A) is a front view showing the light source unit of the headlamp device of FIGS. 10 and 11, and (B) and (C) are diagrams showing an example of an illumination range divided into four segments. FIG. [Figure 13] FIG. 13(A) is a perspective view that shows a schematic view of a shade of a headlight device according to a modification of the fourth embodiment, and FIG. 13(B) is a diagram showing an example of an illumination range that is divided into four segments. [Figure 14] FIG. 11 is a perspective view showing a schematic configuration of a headlamp device according to a fifth embodiment. [Figure 15] 15 is a side view showing a schematic view of the main configuration of the headlamp device shown in FIG. 14. [Figure 16] FIG. 16(A) is a front view showing the light source unit of the headlamp device of FIGS. 14 and 15, and (B) and (C) are diagrams showing an example of an illumination range divided into four segments. FIG. [Figure 17] FIG. 13 is a perspective view showing a schematic configuration of a headlamp device according to a sixth embodiment. [Figure 18] 18 is a side view showing a schematic view of the main configuration of the headlamp device shown in FIG. 17. [Figure 19] FIG. 19(A) is a front view showing the light source unit of the headlamp device of FIGS. 17 and 18, and (B) and (C) are diagrams showing an example of an illumination range divided into two segments. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a headlamp device according to an embodiment will be described with reference to the drawings. Note that the following embodiments are merely examples, and the embodiments can be appropriately combined and each embodiment can be appropriately modified.

[0010] The headlamp device according to the embodiment is, for example, a vehicle headlamp device mounted on a vehicle, such as a four-wheeled motor vehicle, a three-wheeled motor vehicle, or a two-wheeled motor vehicle.

[0011] In the following embodiment, an example will be described in which the illumination state of light irradiated from the headlight device is high beam, which is the state during driving. The light distribution (i.e., light distribution pattern) of light irradiated from the headlight device when the illumination state is high beam is wider in range and higher in illuminance than the light distribution of light irradiated from the headlight device when the illumination state is low beam, which is the state during passing of vehicles. Therefore, when the illumination state of the headlight device is high beam, the visibility of the driver of the vehicle equipped with the headlight device is ensured well. However, when the illumination state is high beam, there is a possibility that the illumination light of the high beam may dazzle the driver of the preceding vehicle or the oncoming vehicle. In order to prevent this dazzlement, the headlight device according to the embodiment performs control to adjust the light distribution, for example, ADB (Adaptive Driving Beam) control of the headlamp. In the headlamp device according to the embodiment, the light distribution of the light irradiated by the high beam is adjusted so that a target area (for example, the area ahead excluding the preceding vehicle and the oncoming vehicle) becomes the illuminated area of ​​the light.

[0012] In the following embodiments, an example will be described in which the headlight device has one headlight module. Therefore, in each embodiment, the headlight device is also called a headlight module. However, the headlight device according to each embodiment may have multiple headlight modules.

[0013] In the drawings, the coordinate axes of an xyz Cartesian coordinate system are shown to facilitate understanding of the description. The x-axis is a coordinate axis parallel to the left-right direction of a vehicle equipped with the headlamp device. That is, the x-axis direction is the width direction of the vehicle. When facing forward of the vehicle, the left direction is the +x-axis direction, and the right direction is the -x-axis direction. The y-axis is a coordinate axis parallel to the up-down direction of the vehicle. The upward direction of the vehicle is the +y-axis direction, and the downward direction of the vehicle is the -y-axis direction. That is, the +y-axis side of the vehicle is the sky side, and the -y-axis side is the road surface side. The z-axis is a coordinate axis perpendicular to the x-axis and y-axis. The z-axis direction is the traveling direction of the vehicle. In the following description, the +z-axis direction is also referred to as the forward direction.

[0014] 1. First embodiment 《1-1》Configuration <Overall composition> FIG. 1 is a perspective view that shows a schematic of a main configuration of a headlight device 1 according to the first embodiment. FIG. 2 is a side view that shows a schematic of a main configuration of the headlight device 1. As shown in FIGS. 1 and 2, the headlight device 1 includes a light source unit 10 having a plurality of light sources 11 to 14, and a single optical unit 100 that is a light-guiding projection optical element (for example, a lens) having an incident surface 110 and an exit surface 120. A plurality of light beams emitted from the light-emitting surfaces 11a to 14a of the plurality of light sources 11 to 14 respectively enter the optical unit 100 from the incident surface 110. The plurality of light beams that enter the optical unit 100 proceed through the optical unit 100 and are projected as a plurality of projected light beams L11 to L14 from the projection areas 120a and 120b of the exit surface 120. In FIG. 2, La shows an example of a light ray that proceeds through the optical unit 100 and is emitted from the exit surface 120. By individually controlling the lighting of the plurality of light sources 11 to 14 (for example, on / off control or dimming control), the light distribution (that is, the light distribution pattern) formed by the plurality of projected lights L11 to L14 is adjusted.

[0015] The exit surface 120 of the optical unit 100 has one or more projection areas (two projection areas 120a, 120b in this example) through which the multiple projection light beams L11-L14 pass. The optical axes A120a, A120b of the projection areas 120a, 120b of the exit surface 120 may be eccentric with respect to the optical axes A11-A14 of the multiple light sources 11-14. The configuration of the headlamp device 1 is not limited to that shown in FIGS. 1 and 2. In this disclosure, when the optical axes A120a, A120b are decentered with respect to the optical axes A11 to A14, this refers to a state in which the optical axes A120a, A120b and the optical axes A11 to A14 do not overlap with each other (i.e., a state in which they are shifted in at least one of the x and y directions), a state in which the directions of the optical axes A120a, A120b and the optical axes A11 to A14 are different from each other (i.e., a state inclined), or both of these states.

[0016] <Light source section 10> As shown in FIG. 1, in the first embodiment, the light source unit 10 includes a plurality of light emitting elements as a plurality of light sources 11-14. In the present disclosure, the light emitting elements are solid-state light sources. The solid-state light source is a light source having directionality. The solid-state light source is, for example, a semiconductor light source. The light sources 11-14 are, for example, light emitting diodes (LEDs). The solid-state light source may be an organic electroluminescence light source. The light sources 11-14 may also be light sources that emit light by irradiating excitation light onto a phosphor applied on a flat surface. LEDs are preferable as the light sources 11-14 because of their small module, ease of arraying, high brightness, safety, and low cost.

[0017] FIG. 3(A) is a front view showing the light source unit 10 of the headlight device 1, and FIGS. 3(B) and (C) are diagrams showing an example of an illumination range divided into four segments. The surfaces of the light sources 11-14 facing the +z-axis direction are light-emitting surfaces 11a-14a. The light source unit 10 includes a plurality of (i.e., N) light-emitting surfaces 11a-14a. The light-emitting surfaces 11a-14a may be arranged on the same plane (i.e., a plane parallel to the xy plane). In the first embodiment, N is 4, but is not limited to 4. Note that N is an integer of 2 or more. In the first embodiment, the light-emitting surfaces 11a and 12a are linearly arranged in the x-axis direction, and the light-emitting surfaces 13a and 14a are linearly arranged in the x-axis direction. In the first embodiment, the light-emitting surfaces 11a and 13a are linearly arranged in the y-axis direction, and the light-emitting surfaces 12a and 14a are linearly arranged in the y-axis direction.

[0018] Each of the light emitting surfaces 11a to 14a has a rectangular shape, such as a square. However, each of the light emitting surfaces 11a to 14a is not limited to a rectangular shape. Each of the light emitting surfaces 11a to 14a may have another shape, such as a circular shape.

[0019] <Optics Department 100> The optical unit 100 is located in the +z-axis direction of the light source unit 10. The optical unit 100 is a light-guiding projection optical element composed of a single optical component. The optical unit 100 is composed of a single lens. A plurality of beams of light emitted from the light-emitting surfaces 11a to 14a of the light source unit 10 are incident on the optical unit 100. The optical unit 100 projects projection beams L11 to L14 composed of a plurality of segments forward (in the +z-axis direction).

[0020] The incident surface 110 of the optical unit 100 has at least one light collecting area, which is, for example, an area that collects light emitted from the light source unit 10 (i.e., an area having a light collecting function). For example, the incident surface 110 has a plurality of light collecting areas 110a, 110b and a plurality of optical axes A110a, A110b. However, the incident surface 110 of the optical unit 100 may have a single light collecting area and its optical axis. In FIG. 1 and FIG. 2, the incident surface 110 has two light collecting areas 110a, 110b. The light collecting areas 110a, 110b protrude toward the light source unit 10 (i.e., toward the -z axis direction) and have a convex portion having an apex (i.e., an apex when the -z axis direction is regarded as the height direction) that extends in a predetermined extension direction (in the first embodiment, the x axis direction). In addition, the profiles (e.g., aspheric profiles) of the light collecting regions 110a and 110b are different on one side (e.g., in the +y-axis direction) and the other side (e.g., in the -y-axis direction) with the top of the convex portion (i.e., the ridge line extending in the x-axis direction) sandwiched therebetween. In other words, the sag amount (i.e., the amount showing the profile as a function of the distance from the optical axis) showing the profile of the light collecting regions 110a and 110b is different on one side and the other side with the top of the convex portion sandwiched therebetween. In the illustrated example, the light collecting regions 110a and 110b have a gentle slope on the +y-axis side of the top of the convex portion and a steep slope on the -y-axis side. The focal points of the light collecting regions 110a and 110b are, for example, on a plane F parallel to the xy plane and on an end surface facing the -z-axis direction of the optical unit 100.

[0021] The optical unit 100 is, for example, integrally formed of the same material. The optical unit 100 is, for example, made of transparent resin. The optical unit 100 is, for example, a light-guiding projection optical element whose interior is filled with a refractive material, which guides light incident from an incident surface 110 and projects it from an exit surface 120. In order to increase the light utilization efficiency, it is desirable to have a small number of optical surfaces of the optical unit 100 through which one light ray passes. In the first embodiment, the optical surfaces of the optical unit 100 through which one light ray passes are two surfaces, the incident surface 110 and the exit surface 120.

[0022] The incident surface 110 is provided at an end of the optical unit 100 in the -z axis direction. The incident surface 110 is disposed in the +y axis direction of the light source unit 10 at a distance from the light source unit 10.

[0023] The incident surface 110 has, for example, a positive power. The shape of the incident surface 110 may be a shape that does not depend on the position in the x-axis direction so as to facilitate manufacturing. The formula expressing the amount of sag of the incident surface 110 in the x-axis direction may be different from the formula expressing the amount of sag in the y-axis direction. In addition, when the y coordinate of the apex of the light-collecting regions 110a and 110b is set to 0, the formula expressing the amount of sag of the incident surface 110 may be different between a region where y≧0 and a region where y<0. In addition, the incident surface 110 (for example, the light-collecting regions 110a and 110b) may be a free-form surface.

[0024] The optical axes A120a, A120b of the light collecting regions 110a, 110b of the incident surface 110 may be decentered with respect to the optical axes A11-A14 of the light sources 11-14. The incident surface 110 may be discontinuous. In other words, the incident surface 110 may have discontinuous portions such as steps.

[0025] When the incident surface 110 has a plurality of light collecting regions 110a, 110b, the light collecting regions 110a, 110b all have the same shape, although the light collecting regions 110a, 110b may have different shapes.

[0026] The light passing through the incident surface 110 (for example, the light collected by the light collecting areas 110a and 110b) is projected by the projection areas 120a and 120b of the exit surface 120 to a region in front (in the +z-axis direction) of the vehicle equipped with the headlamp device 1. The exit surface 120 has at least one projection area that is a region having a projection function. That is, the exit surface 120 has a plurality of projection areas 120a and 120b and a plurality of optical axes A120a and A120b thereof. That is, the exit surface 120 may have a plurality of projection areas 120a and 120b and a plurality of optical axes A120a and A120b. However, the exit surface 120 of the optical unit 100 may have a single projection area and its optical axis. In FIG. 1 and FIG. 2, the exit surface 120 has two projection areas 120a and 120b.

[0027] In addition, the optical unit 100 may have focal points in the projection areas 120a and 120b of the exit surface 120 provided inside the optical unit 100 so that the images collected by the light collecting areas 110a and 110b of the entrance surface 110 are projected by the projection areas 120a and 120b of the exit surface 120, respectively. The projection areas 120a and 120b of the exit surface 120 may be spherical. The projection areas 120a and 120b of the exit surface 120 may be aspheric. A profile of the exit surface 120 in the x-axis direction (e.g., a profile of an aspheric shape) may be different from a profile of the exit surface 120 in the y-axis direction (e.g., a profile of an aspheric shape). In other words, an equation expressing a sag amount expressing a profile of the exit surface 120 in the x-axis direction (e.g., a profile of an aspheric shape) may be different from an equation expressing a sag amount expressing a profile of the exit surface 120 in the y-axis direction (e.g., a profile of an aspheric shape). Furthermore, when the y coordinate of the apex of projection areas 120a and 120b is 0, the formula expressing the amount of sag of exit surface 120 may be different between an area where y≧0 and an area where y<0. Furthermore, exit surface 120 (for example, projection areas 120a and 120b) may be a free-form surface. The formula expressing the amount of sag is a formula expressing the profile of an aspheric shape as a function of the distance from the optical axis, and is a well-known formula.

[0028] The optical axes A120a, A120b of the projection regions 120a, 120b of the emission surface 120 are eccentric with respect to the optical axes A11-A14 of the light sources 11-14 in at least one of the x-axis direction or the y-axis direction. The headlight device 1 may be configured such that the optical axes A120a, A120b of the projection regions 120a, 120b of the emission surface 120 have mutually different degrees of eccentricity with respect to the optical axes of the corresponding light sources. In other words, the degree of eccentricity (i.e., the amount of deviation) of the optical axis A120a of the projection region 120a with respect to the optical axis A11 of the light source 11 (or the optical axis A12 of the light source 12) may be different from the degree of eccentricity (i.e., the amount of deviation) of the optical axis A120b of the projection region 120b with respect to the optical axis A13 of the light source 13 (or the optical axis A14 of the light source 14).

[0029] Furthermore, the emission surface 120 may have discontinuous portions. That is, the emission surface 120 may have discontinuous portions such as steps.

[0030] When the light exit surface 120 has a plurality of projection areas 120a, 120b each having a light collecting function, the projection areas 120a, 120b all have the same shape, although the shapes of the projection areas 120a, 120b may be different from each other.

[0031] 1 and 2, the number of light collection regions 110a, 110b on the entrance surface 110 is equal to the number of projection regions 120a, 120b on the exit surface 120, and the light collection regions 110a, 110b correspond one-to-one to the projection regions 120a, 120b. The combination of the light collection region 110a and the projection region 120a and the combination of the light collection region 110b and the projection region 120b have the same shape. However, the combination of the light collection region 110a and the projection region 120a and the combination of the light collection region 110b and the projection region 120b may have different shapes.

[0032] The optical section 100 may have three or more optical surfaces through which one light ray emitted from the light emitting surface of the light source passes.

[0033] 《1-2》Light distribution 3(B) and (C) show an example of an illumination range divided into four segments, that is, an example of a light distribution pattern of the headlight device 1. Light emitted from each of the light emitting surfaces 11a-14a of the multiple light sources 11-14 passes through the optical unit 100 and becomes different projected lights L11-L14 (i.e., multiple segments) in front of the headlight device 1, illuminating different illumination ranges. The light distribution has, for example, the same number of segments as the number of the light emitting surfaces 11a-14a.

[0034] The light distribution formed by the plurality of projected lights L11-L14 includes an irradiation range consisting of a plurality of segments arranged in at least one of a predetermined first direction (e.g., x-axis direction or y-axis direction) and a second direction (e.g., y-axis direction or x-axis direction) perpendicular to the first direction. The positions and directions of the optical axes A120a, A120b of the emission surface 120 in each of one or more projection regions 120a, 120b may be set so that the ends of adjacent segments in the arrangement direction among the plurality of segments are in contact with each other (e.g., as shown in FIG. 3(B)). The plurality of light sources 11-14 and the optical unit 100 are formed so that the plurality of lights emitted from the light emitting surfaces 11a-14a of the plurality of light sources 11-14 are irradiated to different segments from each other as the plurality of projected lights L11-L14 from the emission surface 120 of the optical unit 100.

[0035] In forming the light distribution, it is preferable that the exit surface 120 of the optical unit 100 has a plurality of optical axes. It is preferable that the projected lights of adjacent segments (for example, L12 and L14, L14 and L11, and L11 and L13 in Figs. 3(B) and (C)) are emitted from projection areas 120a and 120b having different optical axes A120a and A120b on the exit surface 120.

[0036] By arranging the light emitted from different emission surfaces 120, i.e., projection areas 120a, 120b, side by side, it is possible to arrange the segments corresponding to light-emitting surfaces 13a, 14a in the same row in the x-axis direction as the segments corresponding to light-emitting surfaces 11a, 12a, as shown in FIG. 3(B).

[0037] The spacing between the multiple segments of projected light is determined by the degree of eccentricity of optical axes A120a, A120b of projection areas 120a, 120b of exit surface 120 with respect to optical axes A11-A14 of light sources 11-14, and the spacing between light sources 11-14.

[0038] As shown in Fig. 3(C), it is desirable that the ends of adjacent segments of projected light be in contact with a partial overlap. The optical axes A120a, A120b of the projection areas 120a, 120b of the emission surface 120 are decentered so that the boundaries of the segments are in contact (including partial overlap) in the light distribution. In this disclosure, the boundary of a segment refers to the boundary line at the end of the segment where the luminous intensity is 625 cd. In contact means that both boundaries of adjacent segments are in contact, or both boundaries are located on the adjacent segment.

[0039] The intervals between the segments emitted from the projection areas including the same optical axis on the emission surface 120 are all the same, but the intervals between the segments do not have to be the same.

[0040] The widths of each segment of the light distribution in at least one of the x-axis direction (horizontal direction of the vehicle) and y-axis direction (vertical direction of the vehicle) are equal to each other. In other words, when the light sources 11-14 are all of the same shape, and the emission surface 120 of the optical unit 100 has multiple optical axes, the focal lengths of the projection areas 120a, 120b corresponding to each optical axis are all equal. However, the widths of each segment of the light distribution in at least one of the horizontal direction and the vertical direction may include unequal widths. The areas of the light emitting surfaces 11a-14a corresponding to each segment may be different from each other. Furthermore, when the emission surface 120 has multiple optical axes, the focal lengths of the projection areas corresponding to each optical axis may be different.

[0041] 1-3 Effects According to the first embodiment, optical unit 100 is configured by a single optical element, and therefore the focal position of exit surface 120 with respect to entrance surface 110 is fixed. Therefore, the influence of variation in the position of optical unit 100 on the light distribution is small.

[0042] Furthermore, because the exit surface 120 has a plurality of optical axes A120a, A120b, the exit directions of the projected lights L11-L14 that form the light distribution can be designed arbitrarily depending on the degree of eccentricity of each of the optical axes A120a, A120b with respect to the optical axes A11-A14 of the light sources 11-14. In other words, by adjusting the eccentricity of the optical axes A11-A14 of the light sources 11-14 with respect to the optical axes A120a, A120b of the optical unit 100, the positions of the segments of the projected light that form the light distribution can be set.

[0043] In addition, by using the distance between adjacent light sources 11-14 and the degree of eccentricity of the optical axes A120a, A120b of the emission surface 120 with respect to the optical axes A11-A14 of the light sources 11-14 as parameters, the size of the distance between the segments can be precisely designed, thereby reducing the occurrence of uneven brightness of the illumination light.

[0044] In addition, since adjacent segments of the multiple segments of projected light are segments of projected light projected from projection areas 120a, 120b of different optical axes A120a, A120b, as shown in Figures 3(B) and (C), the effect of light seeping into adjacent segments on the light distribution can be reduced.

[0045] 2. Second embodiment FIG. 4 is a perspective view that shows a schematic of the main configuration of the headlight device 2 according to the second embodiment. FIG. 5 is a side view that shows a schematic of the main configuration of the headlight device 2. In the first embodiment, the light collecting areas 110a and 110b that are convex parts having two apexes extending in the x-axis direction are provided on the incident surface 110 of the optical unit 100, and the projection areas 120a and 120b that are two convex parts are provided on the exit surface 120. In the second embodiment, as shown in FIG. 4 and FIG. 5, the light collecting area 210a that is a convex part having a single apex extending in the x-axis direction is provided on the incident surface 210 of the optical unit 200, and the projection area 220a that is a single convex part is provided on the exit surface 220. However, the number of projection areas may be two or more as long as it is one or more.

[0046] The headlamp device 2 includes a light source unit 20 having a plurality of light sources 21-24, and a single optical unit 200 which is a light-guiding projection optical element (for example, a lens) having an entrance surface 210 and an exit surface 220. A plurality of light beams emitted from the light-emitting surfaces of the plurality of light sources 21-24 enter the optical unit 200 from the entrance surface 210. In FIG. 5, La indicates an example of a light ray which travels through the optical unit 200 and is exited from the exit surface 220. The plurality of light beams which enter the optical unit 200 are projected as a plurality of projection light beams L21-L24 from a projection region 220a of the exit surface 220. The light distribution formed by the plurality of projection light beams L21-L24 is adjusted by individually controlling the lighting of the plurality of light sources 21-24.

[0047] Moreover, the optical axis A220a of the projection area 220a of the exit surface 220 is decentered with respect to the optical axes A21-A24 of the multiple light sources 21-24.

[0048] FIG. 6(A) is a front view showing the light source unit 20 of the headlight device 2, and FIGS. 6(B) and (C) are diagrams showing an example of an illumination range divided into four segments. The surfaces of the light sources 21-24 facing the +z-axis direction are the light-emitting surfaces 21a-24a. The light source unit 20 includes a plurality of light-emitting surfaces 21a-24a. The light-emitting surfaces 21a-24a are arranged, for example, on the same plane (i.e., a plane parallel to the xy plane). In the second embodiment, the light-emitting surfaces 21a and 22a are arranged in the x-axis direction, and the light-emitting surfaces 23a and 24a are arranged in the x-axis direction. Moreover, the light-emitting surfaces 21a and 23a are arranged in the y-axis direction, and the light-emitting surfaces 22a and 24a are arranged in the y-axis direction.

[0049] The optical unit 200 is located in the +z-axis direction of the light source unit 20. A plurality of light beams emitted from the light emitting surfaces 21a to 24a of the light source unit 20 are incident on the optical unit 200. The optical unit 200 projects projection light beams L21 to L24 consisting of a plurality of segments forward (in the +z-axis direction).

[0050] The incident surface 210 of the optical unit 200 has, for example, a single light collection region 210a that is a region that collects light emitted from the light source unit 20. That is, the incident surface 210 has a single light collection region 210a and a single optical axis A210a. However, the incident surface 210 of the optical unit 200 may have a plurality of light collection regions and their optical axes. The focal point of the light collection region 210a is, for example, a plane F parallel to the xy plane, on an end surface of the optical unit 200 facing the -z axis direction. The shape of the light collection region 210a of the incident surface 210 is the same as that of the light collection region 110a in the first embodiment.

[0051] As described above, according to the second embodiment, optical unit 200 is configured by a single optical element, and therefore the focal position of exit surface 220 with respect to entrance surface 210 is fixed. Therefore, the influence of the variation in the position of optical unit 200 on the light distribution is small.

[0052] Furthermore, by changing the interval between adjacent light sources 21-24 and the degree of eccentricity of the optical axis A220a of the exit surface 220 with respect to the optical axes A21-A24 of the light sources 21-24 as parameters, the size of the interval between the segments can be precisely designed.

[0053] Except for the above, the second embodiment is the same as the first embodiment.

[0054] 3. Third embodiment 3-1. Configuration FIG. 7 is a perspective view that shows a schematic of the main configuration of the headlight device 3 according to the third embodiment. FIG. 8 is a side view that shows a schematic of the main configuration of the headlight device 3. As shown in FIG. 7 and FIG. 8, the headlight device 3 includes a light source unit 30 having a plurality of light sources 31 and 32, a single optical unit 300 that is a light-guiding projection optical element (for example, a lens) having an incident surface 310 and an exit surface 320, and a shade 340 that is a light-shielding member. A plurality of lights emitted from the light-emitting surfaces of the plurality of light sources 31 and 32 are incident into the optical unit 300 from the incident surface 310 through the openings 341 and 342 of the shade 340. The plurality of lights that have entered the optical unit 300 are projected as a plurality of projected lights L31 and L34 from the projection area 320a of the exit surface 320. In FIG. 8, La shows an example of a light ray that travels through the optical unit 300 and is emitted from the exit surface 320. The light distribution formed by the plurality of projected lights L31, L32 is adjusted by individually controlling the lighting of the plurality of light sources 31, 32 (for example, on / off control or dimming control).

[0055] The exit surface 320 of the optical unit 300 has a projection area 320a through which the multiple projected light beams L11 to L14 pass. The optical axis A320a of the projection area 320a of the exit surface 320 may be eccentric with respect to the optical axes A31 and A34 of the multiple light sources 31 and 32. The configuration of the headlight device 3 is not limited to that shown in Figs. 7 and 8. Here, the optical axis A320a being eccentric with respect to the optical axes A31 and A32 refers to a state in which the optical axis A320a and the optical axes A31 and A32 do not overlap with each other (i.e., a state in which they are shifted in at least one of the x direction and the y direction), a state in which the direction of the optical axis A320a is different from that of the optical axes A31 and A32 (i.e., a state inclined), or both of these states.

[0056] <Light source section 30> 7, in the third embodiment, a light source section 30 includes a plurality of light emitting elements as a plurality of light sources 31 and 32. The light emitting elements are the same as those described in the first embodiment.

[0057] FIG. 9(A) is a front view showing the light source unit 30 of the headlight device 3, and FIG. 9(B) and (C) are diagrams showing an example of an illumination range divided into two segments. The surfaces of the light sources 31 and 32 facing the +z-axis direction are light-emitting surfaces 31a and 32a. The light source unit 30 includes a plurality of (i.e., N) light-emitting surfaces 31a and 32a. The light-emitting surfaces 31a and 32a may be arranged on the same plane (i.e., a plane parallel to the xy plane). In the third embodiment, N is 2, but is not limited to 2. Note that N is an integer equal to or greater than 2. In the third embodiment, the light-emitting surfaces 31a and 32a are arranged in the x-axis direction. The shapes of the light-emitting surfaces 31a and 32a are the same as those described in the first embodiment.

[0058] Shade 340 In the headlamp device 3, as shown in Fig. 7 and Fig. 8, a shade 340 is installed in the +z-axis direction of the light source unit 30. The shade 340 has openings 341, 342 facing the light-emitting surfaces 31a, 32a of the light sources 31, 32, and limits the luminous flux contributing to the light distribution by blocking the x-direction ends of the light emitted from the light-emitting surfaces 31a, 32a. In other words, the shade 340 is a structure that limits the size of the luminous flux diameter of the multiple lights emitted from the light-emitting surfaces 31a, 32a of the multiple light sources 31, 32, respectively. In addition, the luminous flux contributing to the light distribution may be limited by blocking both the x-direction ends and the y-direction ends of the light emitted from the light-emitting surfaces 31a, 32a of the light sources 31, 32.

[0059] The shape of the openings 341, 342 of the shade 340 is, for example, rectangular. The shape of the openings 341, 342 of the shade 340 is not limited to rectangular. For example, the shape of the openings 341, 342 may be other shapes, such as the openings shown in FIG. 13(A) described later. The shade 340 is made of, for example, a metal such as stainless steel. The area of ​​the incidence region of the incident light that passes through one of the multiple openings 341, 342 among the multiple lights and hits the incidence surface 310 is smaller than the area of ​​the light emitting surface 31a or 32a of the light source 31 or 32 corresponding to the incident light among the multiple light sources 31 and 32.

[0060] <Optics Department 300> The optical unit 300 is located in the +z-axis direction of the light source unit 30. The optical unit 300 is a light-guiding projection optical element composed of a single optical component. The optical unit 300 is composed of a single lens. A plurality of lights emitted from the light-emitting surfaces 31a, 32a of the light source unit 30 are incident on the optical unit 300. The optical unit 300 projects projection light consisting of a plurality of segments forward (in the +z-axis direction). The plurality of lights emitted from the light-emitting surfaces 31a, 32a of the plurality of light sources 31, 32 pass through two of the plurality of optical surfaces of the optical unit 300 and are projected as a plurality of projection lights L31, L32.

[0061] The incident surface 310 of the optical unit 300 has, for example, at least one light collecting region that collects the light emitted from the light source unit 30. That is, the incident surface 310 has a light collecting region 310a and an optical axis A310a. The focal point of the light collecting region 310a is, for example, a plane F parallel to the xy plane, and is on an end surface of the optical unit 300 facing the -z axis direction. It is also possible that the incident surface 310 does not have a light collecting region.

[0062] The optical unit 300 is integrally formed of, for example, the same material. The optical unit 300 is made of, for example, a transparent resin. The optical unit 300 is, for example, a light-guiding projection optical element whose interior is filled with a refractive material, which guides light incident from an incident surface 310 and projects it from an exit surface 320. In order to increase the light utilization efficiency, it is desirable to have a small number of optical surfaces of the optical unit 300 through which one light ray passes. In the third embodiment, the optical surfaces of the optical unit 300 through which one light ray passes are two surfaces, the incident surface 310 and the exit surface 320.

[0063] The incident surface 310 is provided at an end of the optical unit 300 in the -z axis direction. The incident surface 310 is disposed in the +y axis direction of the light source unit 30 at a distance from the light source unit 30.

[0064] Incident surface 310 has, for example, positive power. The shape of incident surface 310 may be a shape that does not depend on the position in the x-axis direction so as to facilitate manufacturing. The formula expressing the amount of sag of incident surface 310 in the x-axis direction may be different from the formula expressing the amount of sag in the y-axis direction. In addition, when the y coordinate of the apex of light-collecting region 310a is set to 0, the formula expressing the amount of sag of incident surface 310 may be different between a region where y≧0 and a region where y<0. In addition, incident surface 310 (for example, light-collecting region 310a) may be a free-form surface.

[0065] The optical axis A320a of the light collecting region 310a of the incident surface 310 may be decentered with respect to the optical axes A31, A32 of the light sources 31, 32. The incident surface 310 may be discontinuous. That is, the incident surface 310 may have discontinuous portions such as steps.

[0066] Light passing through the entrance surface 310 (for example, light collected by the light collecting area 310a) is projected by the projection area 320a of the exit surface 320 to an area in front (in the +z-axis direction) of the vehicle equipped with the headlamp device 3. The exit surface 320 has at least one projection area that is an area having a projection function. In other words, the exit surface 320 has the projection area 320a and its optical axis A320a. The multiple light beams emitted from the light emitting surfaces 31a, 32a of the multiple light sources 31, 32 are projected as projected light beams L31, L32 to individual illumination areas via the optical unit 300.

[0067] In addition, the focal point of the projection area 320a of the exit surface 320 may be provided inside the optical unit 300 so that the image collected by the light collecting area 310a of the entrance surface 310 is projected by the projection area 320a of the exit surface 320. The projection area 320a of the exit surface 320 may be a spherical surface. The projection area 320a of the exit surface 320 may be an aspheric surface. The formula expressing the sag amount of the exit surface 320 in the x-axis direction may be different from the formula expressing the sag amount in the y-axis direction. In addition, when the y coordinate of the top of the projection area 320a is set to 0, the formula expressing the sag amount of the exit surface 320 may be different between a region where y≧0 and a region where y<0. In addition, the exit surface 320 (for example, the projection area 320a) may be a free-form surface.

[0068] An optical axis A320a of a projection area 320a of the exit surface 320 is decentered with respect to the optical axes A31, A32 of the light sources 31, 32 in at least one of the x-axis direction and the y-axis direction.

[0069] Furthermore, the light exit surface 320 may have a discontinuous portion. That is, the light exit surface 320 may have a discontinuous portion such as a step.

[0070] When the light exit surface 320 has a plurality of projection areas 320a having a light collecting function, the shapes of the projection areas 320a are all the same, although the shapes of the projection areas 320a may be different from each other.

[0071] The number of optical surfaces of the optical section 300 through which one light ray emitted from the light emitting surface of the light source passes may be three or more.

[0072] 3-2 Light distribution 9(B) and (C) show an example of an illumination range divided into two segments, that is, an example of a light distribution pattern of the headlight device 3. The light emitted from each of the light emitting surfaces 31a, 32a of the multiple light sources 31, 32 passes through the optical unit 300 and becomes different projected lights L31, L32 (i.e., multiple segments) in front of the headlight device 3, illuminating different illumination ranges. The light distribution has, for example, the same number of segments as the number of the light emitting surfaces 31a, 32a.

[0073] The interval between the multiple segments of the projected light L31, L32 is determined by the degree of eccentricity of the optical axis A320a of the projection area 320a of the emission surface 320 with respect to the optical axes A31, A32 of the light sources 31, 32 and the size of the interval between the light sources 31, 32.

[0074] As shown in Fig. 9(C), it is desirable that the ends of adjacent segments of projected light be in contact with a partial overlap. The optical axis A320a of the projection area 320a of the emission surface 320 is decentered so that the boundaries of the segments are in contact (including partial overlap) in the light distribution. The boundary of the segment refers to the boundary line at the end of the segment where the luminous intensity is 625 cd. In contact means that both boundaries of adjacent segments are in contact, or both boundaries are located on the adjacent segment.

[0075] The light emitted from the light sources 31 and 32 is partially blocked, so that the luminous flux that contributes to the light distribution is limited.

[0076] 3-3 Effects As described above, according to the third embodiment, optical unit 300 is configured by a single optical element, and therefore the focal position of exit surface 320 with respect to entrance surface 310 is fixed. Therefore, the influence of variation in the position of optical unit 300 on the light distribution is small.

[0077] In addition, by using the parameters of the spacing between adjacent light sources 31, 32, the position of the openings 341, 342 of the shade 340, and the degree of eccentricity of the optical axis A320a of the exit surface 320 relative to the optical axes A31, A32 of the light sources 31, 32, the size of the spacing between the segments can be precisely designed.

[0078] Furthermore, since the light flux contributing to the light distribution is limited by the shade 340, the degree of influence on the projected lights L31 and L32 due to variations in the arrangement of the light sources 31 and 32 in the light distribution can be reduced.

[0079] Furthermore, by reducing the width of each of the projection lights L31, L32 using the shade 340, it is possible to reduce the curvature in the x-axis direction in the equation expressing the amount of sag in the x-axis direction for the incident surface 310 of the optical unit 300. This also simplifies the shape of the optical unit 300. Note that the direction in which the width of each of the projection lights L31, L32 is narrowed by the shade 340 is not limited to the x-axis direction, and may be the y-axis direction or both the x-axis and y-axis directions.

[0080] Except for the above, the third embodiment is the same as the first or second embodiment.

[0081] 4. Fourth embodiment {4-1} Configuration <Overall composition> FIG. 10 is a perspective view that shows a schematic of the main configuration of the headlight device 4 according to the fourth embodiment. FIG. 11 is a side view that shows a schematic of the main configuration of the headlight device 4. As shown in FIG. 10 and FIG. 11, the headlight device 4 includes a light source unit 40 having a plurality of light sources 41 to 44, a shade 440 as a light blocking member, and a single optical unit 400 that is a light guide projection optical element (for example, a lens) having an incident surface 410 and an exit surface 420. A plurality of lights emitted from the light emitting surfaces of the plurality of light sources 41 to 44 pass through openings 441 to 444 of the shade 440, respectively, and proceed toward the incident surface 410, and enter the optical unit 400 from the incident surface 410. The plurality of lights that enter the optical unit 400 are projected as a plurality of projection lights L41 to L44 from the projection areas 420a and 420b of the exit surface 420. 11, La indicates an example of a light ray that travels inside the optical unit 400 and is emitted from the emission surface 420. The light distribution formed by the plurality of projected lights L41-L44 is adjusted by individually controlling the lighting of the plurality of light sources 41-44 (for example, by on / off control or dimming control).

[0082] The emission surface 420 of the optical unit 400 has one or more projection areas (two projection areas 420a, 420b in this example) through which the multiple projection light beams L41 to L44 pass. The optical axes A420a, A420b of the projection areas 420a, 420b of the emission surface 420 may be eccentric with respect to the optical axes A41 to A44 of the multiple light sources 41 to 44. The configuration of the headlamp device 4 is not limited to that shown in FIGS. 10 and 11. In this disclosure, when the optical axes A420a, A420b are decentered with respect to the optical axes A41 to A44, this refers to a state in which the optical axes A420a, A420b and the optical axes A41 to A44 do not overlap with each other (i.e., a state in which they are shifted in at least one of the x and y directions), a state in which the directions of the optical axes A420a, A420b and the optical axes A41 to A44 are different (i.e., a state inclined), or both of these states.

[0083] <Light source section 40> As shown in FIG. 10, in the fourth embodiment, the light source section 40 includes a plurality of light emitting elements serving as a plurality of light sources 41-44.

[0084] FIG. 12(A) is a front view showing the light source unit 40 of the headlight device 4, and FIGS. 12(B) and (C) are diagrams showing an example of an illumination range divided into four segments. The surfaces of the light sources 41 to 44 facing the +z-axis direction are light-emitting surfaces 41a to 44a. The light source unit 40 includes a plurality of (i.e., N) light-emitting surfaces 41a to 44a. The light-emitting surfaces 41a to 44a may be arranged on the same plane (i.e., a plane parallel to the xy plane). In the fourth embodiment, N is 4, but is not limited to 4. Note that N is an integer of 2 or more. In the fourth embodiment, the light-emitting surfaces 41a and 42a are linearly arranged in the x-axis direction, and the light-emitting surfaces 43a and 44a are linearly arranged in the x-axis direction. In the fourth embodiment, the light-emitting surfaces 41a and 43a are linearly arranged in the y-axis direction, and the light-emitting surfaces 42 ... y-axis direction.

[0085] Each of the light emitting surfaces 41a to 44a has a rectangular shape, such as a square. However, each of the light emitting surfaces 41a to 44a is not limited to a rectangular shape. Each of the light emitting surfaces 41a to 44a may have another shape, such as a circular shape.

[0086] <Shade 440> In the headlamp device 4, as shown in Fig. 10 and Fig. 11, a shade 440 is installed in the +z-axis direction of the light source unit 30. The shade 440 has openings 441-444 facing the light emitting surfaces 41a-44a of the light sources 41-44, and limits the luminous flux contributing to the light distribution by blocking the x-direction ends of the light emitted from the light emitting surfaces 41a-44a. In other words, the shade 440 is structured to limit the size of the luminous flux diameter of the multiple lights emitted from the light emitting surfaces 41a-44a of the multiple light sources 41-44. The shade 440 may also limit the luminous flux contributing to the light distribution by blocking both the x-direction ends and the y-direction ends of the light emitted from the light emitting surfaces 41a-44a of the light sources 41-44. The shape of the openings 441-444 of the shade 440 is, for example, rectangular. The shape of the openings 441 to 444 of the shade 440 is not limited to a rectangle.

[0087] <Optics Department 400> The optical unit 400 is located in the +z-axis direction of the light source unit 40. The optical unit 400 is a light-guiding projection optical element composed of a single optical component. The optical unit 400 is composed of a single lens. A plurality of beams of light emitted from the light-emitting surfaces 41a to 44a of the light source unit 40 are incident on the optical unit 400. The optical unit 400 projects projection beams L41 to L44 composed of a plurality of segments forward (in the +z-axis direction).

[0088] The incident surface 410 of the optical unit 400 has at least one light collecting area that collects light emitted from the light source unit 40, for example. For example, the incident surface 410 has a plurality of light collecting areas 410a, 410b and a plurality of optical axes A410a, A410b. However, the incident surface 110 of the optical unit 100 may have a single light collecting area and its optical axis. In FIG. 10 and FIG. 11, the incident surface 110 has two light collecting areas 410a, 410b. The focal points of the light collecting areas 410a, 410b are, for example, a plane F parallel to the xy plane, on the end surface of the optical unit 400 facing the -z axis direction. It is also possible that the incident surface 410 does not have a light collecting area.

[0089] The optical unit 400 is integrally formed of, for example, the same material. The optical unit 400 is made of, for example, a transparent resin. The optical unit 400 is, for example, a light-guiding projection optical element whose interior is filled with a refractive material, which guides light incident from an incident surface 410 and projects it from an exit surface 420. In order to increase the light utilization efficiency, it is desirable to have a small number of optical surfaces of the optical unit 400 through which one light ray passes. In the first embodiment, the optical surfaces of the optical unit 400 through which one light ray passes are two surfaces, the incident surface 410 and the exit surface 420.

[0090] The incident surface 410 is provided at an end of the optical unit 400 in the -z-axis direction. The incident surface 410 is disposed in the +y-axis direction of the light source unit 40 and in the +y-axis direction of the shade 440 at a distance from the shade 440.

[0091] The incident surface 410 has, for example, a positive power. The shape of the incident surface 410 is the same as the shape of the incident surface 110 in the first embodiment.

[0092] The light passing through the incident surface 410 (for example, the light collected by the light collecting areas 410a, 410b) is projected by the projection areas 420a, 420b of the exit surface 420 to a region in front (in the +z-axis direction) of the vehicle equipped with the headlamp device 4. The exit surface 420 has at least one projection area that is an area having a projection function. That is, the exit surface 420 has a plurality of projection areas 420a, 420b and a plurality of optical axes A420a, A420b thereof. For example, the exit surface 420 has a plurality of projection areas 420a, 420b and a plurality of optical axes A420a, A420b. However, the exit surface 420 of the optical unit 400 may have a single projection area and its optical axis.

[0093] Emission surface 420 has, for example, a positive power. The shape of emission surface 420 is the same as the shape of emission surface 120 in the first embodiment.

[0094] 《4-2》Light distribution 12(B) and (C) show an example of an illumination range divided into four segments, that is, an example of a light distribution pattern of the headlight device 4. Light emitted from each of the light emitting surfaces 11a-14a of the multiple light sources 41-44 passes through the openings 441-444 of the shade 440, respectively, and passes through the optical unit 400 to become different projected lights L41-L44 (i.e., multiple segments) in front of the headlight device 4, and illuminate different illumination ranges. The light distribution has, for example, the same number of segments as the number of the light emitting surfaces 41a-44a.

[0095] In forming the light distribution, it is preferable that the exit surface 420 of the optical unit 400 has a plurality of optical axes. It is preferable that the projected lights of adjacent segments are emitted from projection areas 420a and 420b having different optical axes A420a and A420b on the exit surface 420.

[0096] By arranging the light emitted from different emission surfaces 420, i.e., projection areas 420a, 420b, side by side, it is possible to arrange the segments corresponding to light-emitting surfaces 43a, 44a in the same row in the x-axis direction as the segments corresponding to light-emitting surfaces 41a, 42a, as shown in FIG. 12(B).

[0097] The spacing between the multiple segments of the projected light is determined by the degree of eccentricity of the optical axes A420a, A420b of the projection areas 420a, 420b of the exit surface 420 relative to the optical axes A41-A44 of the light sources 41-44 and the spacing between the light sources 41-44.

[0098] As shown in Fig. 12(C), it is desirable for the ends of adjacent segments of projected light to be in contact with a partial overlap. The optical axes A420a, A420b of the projection areas 420a, 420b of the exit surface 420 are decentered so that the boundaries of the segments are in contact (including partial overlap) in the light distribution.

[0099] The intervals between the segments emitted from the projection areas including the same optical axis on the emission surface 420 are all the same, but the intervals between the segments do not have to be the same.

[0100] The widths of each segment of light distribution in at least one of the x-axis direction (horizontal direction of the vehicle) and y-axis direction (vertical direction of the vehicle) are equal to each other. In other words, when the light sources 41-44 are all of the same shape, and the emission surface 420 of the optical unit 400 has multiple optical axes, the focal lengths of the projection areas 420a, 420b corresponding to each optical axis are all equal. However, the widths of each segment of light distribution in at least one of the horizontal direction and the vertical direction may include unequal widths. The areas of the light emitting surfaces 41a-44a corresponding to each segment may be different from each other. Furthermore, when the emission surface 420 has multiple optical axes, the focal lengths of the projection areas corresponding to each optical axis may be different.

[0101] 4-3 Effects As described above, according to the fourth embodiment, optical unit 400 is configured by a single optical element, and therefore the focal position of exit surface 420 with respect to entrance surface 410 is fixed. Therefore, the influence of variation in the position of optical unit 400 on the light distribution is small.

[0102] In addition, by using the parameters of the spacing between adjacent light sources 41-44, the positions of the openings 441-444 of the shade 440, and the degree of eccentricity of the optical axes A420a, A420b of the exit surface 420 relative to the optical axes A41-A44 of the light sources 41-44 as parameters, the size of the spacing between the segments can be precisely designed.

[0103] Furthermore, by limiting the luminous flux contributing to the light distribution by the shade 440, it is possible to reduce the degree of influence that appears on the projected lights L41 to L44 due to variations in the arrangement of the light sources 41 to 44 in the light distribution.

[0104] Furthermore, by reducing the width of each of the projection lights L41 to L44 using the shade 440, it is possible to reduce the curvature in the x-axis direction in the equation expressing the amount of sag in the x-axis direction for the incident surface 410 of the optical unit 400. This also simplifies the shape of the optical unit 400. Note that the direction in which the shade 440 reduces the width of each of the projection lights L41 to L44 is not limited to the x-axis direction, and may be the y-axis direction or both the x-axis and y-axis directions.

[0105] In addition, since adjacent segments among the multiple segments of projected light L41 to L44 are segments of projected light projected from projection areas 420a, 420b of different optical axes A420a, A420b, as shown in Figures 12(B) and (C), the effect of light seeping into adjacent segments on the light distribution can be reduced.

[0106] Except for the above, the fourth embodiment is the same as any one of the first to third embodiments.

[0107] 4-4 Variations FIG. 13(A) is a perspective view that shows a schematic view of a shade 740 as a light blocking member of a headlight device according to a modification of the fourth embodiment. FIG. 13(B) is a view showing an example of an illumination range divided into four segments when the shade 740 is used. The headlight device according to the modification of the fourth embodiment is obtained by replacing the shade 440 of the headlight device 4 shown in FIG. 10 with the shade 740 shown in FIG. 13(A). The shade 740 has openings 741-744 that are through holes. The openings 741-744 are shaped such that the width in a direction perpendicular to the predetermined direction (the width in the x-axis direction in the illustrated example) becomes narrower as the openings advance in a predetermined direction (the -y-axis direction in the illustrated example). That is, the openings 741-744 are shaped such that the width gradually becomes narrower toward the predetermined direction. The shape of the openings 741-744 is a shape in which the hypotenuse (i.e., the longest side) of a right-angled triangle is bulged in an arc shape (i.e., a shape convex outward). However, the shape of the openings 741-744 may be other shapes. For example, the shape of the openings 741-744 may be other shapes in which the width in a direction perpendicular to a predetermined direction becomes narrower as the openings advance in the predetermined direction. In addition, the number of the openings 741-744 is not limited to four. In addition, the shapes and sizes of the openings 741-744 are the same as each other, but the shapes and sizes of the openings 741-744 may be different from each other depending on the required light distribution.

[0108] By using shade 740 having openings 741-744 as shown in FIG. 13(A), it is possible to form a light distribution in which projected lights L71-L74 are aligned as shown in FIG. 13(B), and it is possible to obtain a light distribution in which the illuminance gradually decreases as one moves in the +y-axis direction (i.e., a light distribution in which the illuminance changes smoothly).

[0109] <5> Fifth embodiment FIG. 14 is a perspective view showing a schematic configuration of the headlight device 5 according to the fifth embodiment. FIG. 15 is a side view showing a schematic configuration of the headlight device 5. In the fourth embodiment, the incident surface 410 of the optical unit 400 is provided with the light collection areas 410a and 410b of the convex portion having two apexes extending in the x-axis direction, and the emission surface 420 is provided with the projection areas 420a and 420b which are two convex portions. In the fifth embodiment, as shown in FIG. 14 and FIG. 15, the incident surface 510 of the optical unit 500 is provided with the light collection area 510a which is a single convex portion, and the emission surface 520 is provided with the projection area 520a which is a single convex portion.

[0110] The headlamp device 5 includes a light source unit 50 having a plurality of light sources 51-54, a shade 540 as a light blocking member, and a single optical unit 500 which is a light guide projection optical element (for example, a lens) having an incident surface 510 and an exit surface 520. A plurality of light beams emitted from the light emitting surfaces of the plurality of light sources 51-54 pass through openings 541-544 of the shade 540, respectively, and enter the optical unit 500 from the incident surface 510. The shade 540 has a structure for restricting the size of the luminous flux diameter of the plurality of light beams emitted from the light emitting surfaces 51a-54a of the plurality of light sources 51-54, respectively. The plurality of light beams entering the optical unit 500 are projected as a plurality of projection light beams L51-L54 from a projection area 520a of the exit surface 520. In FIG. 15, La indicates an example of a light beam that travels through the optical unit 500 and is emitted from the exit surface 520. The light distribution formed by the plurality of projection lights L51-L54 is adjusted by individually controlling the lighting of the plurality of light sources 51-54. The shape of the openings 541-542 may be another shape, such as the opening shown in FIG. 13(A).

[0111] Moreover, the optical axis A520a of the projection area 520a of the exit surface 520 is decentered with respect to the optical axes A51-A54 of the multiple light sources 51-54.

[0112] FIG. 16(A) is a front view showing the light source unit 50 of the headlight device 5, and FIGS. 16(B) and (C) are diagrams showing an example of an illumination range divided into four segments. The surfaces of the light sources 51 to 54 facing the +z-axis direction are light-emitting surfaces 51a to 54a. The light source unit 50 includes a plurality of light-emitting surfaces 51a to 54a. The light-emitting surfaces 51a to 54a are arranged, for example, on the same plane (i.e., a plane parallel to the xy plane). In the fifth embodiment, the light-emitting surfaces 51a and 52a are arranged in the x-axis direction, and the light-emitting surfaces 53a and 54a are arranged in the x-axis direction. Moreover, the light-emitting surfaces 51a and 53a are arranged in the y-axis direction, and the light-emitting surfaces 52a and 54a are arranged in the y-axis direction.

[0113] The optical unit 500 is located in the +z-axis direction of the light source unit 50. A plurality of beams of light emitted from the light emitting surfaces 51a to 54a of the light source unit 50 are incident on the optical unit 500. The optical unit 500 projects projection light made up of a plurality of segments forward (in the +z-axis direction).

[0114] The incident surface 510 of the optical unit 500 has, for example, a single light collecting region 510a which is a region for collecting light emitted from the light source unit 50. That is, the incident surface 510 has a single light collecting region 510a and a single optical axis A510a. However, the incident surface 510 of the optical unit 500 may have a plurality of light collecting regions and their optical axes. The focal point of the light collecting region 510a is, for example, a plane F parallel to the xy plane, on an end surface of the optical unit 500 facing the -z axis direction. The shape of the light collecting region 510a of the incident surface 510 is the same as that of the light collecting region in the first to fourth embodiments.

[0115] As described above, according to the fifth embodiment, optical unit 500 is configured by a single optical element, and therefore the focal position of exit surface 520 with respect to entrance surface 510 is fixed. Therefore, the influence of variation in the position of optical unit 500 on the light distribution is small.

[0116] In addition, by changing the parameters such as the spacing between adjacent light sources 51-54, the positions of the openings 541-544 of the shade 540, and the degree of eccentricity of the optical axis A520a of the exit surface 520 relative to the optical axes A51-A54 of the light sources 51-54, the size of the spacing between the segments can be precisely designed.

[0117] Furthermore, since the light flux contributing to the light distribution is limited by the shade 540, the degree of influence on the projected lights L51, L52 due to variations in the arrangement of the light sources 51, 52 in the light distribution can be reduced.

[0118] Except for the above, the fifth embodiment is the same as any one of the first to fourth embodiments.

[0119] 6. Sixth embodiment FIG. 17 is a perspective view that shows a schematic of the main configuration of the headlight device 6 according to the sixth embodiment. FIG. 18 is a side view that shows a schematic of the main configuration of the headlight device 6. As shown in FIGS. 17 and 18, the headlight device 6 includes a light source section 60 having a plurality of light sources 61, 62, and a single optical section 600 that is a light-guiding projection optical element (for example, a lens) having an incident surface 610 and an exit surface 620. In the third embodiment, the shade 340 limits the width of the plurality of light beams emitted from the light-emitting surfaces of the light sources 31, 32, respectively. In the sixth embodiment, however, the light-emitting elements that limit the width of the emitted light are adopted as the plurality of light sources 61, 62. That is, in the sixth embodiment, each of the plurality of light sources 61, 62 has a structure that limits the size of the luminous flux diameter of the plurality of light beams emitted from the light-emitting surface. The plurality of light beams emitted from the light sources 61, 62 proceed toward the incident surface 410 and enter the optical section 600 from the incident surface 610. The multiple light beams incident on the optical unit 600 are projected as multiple projected light beams L61, L62 from projection areas 620a, 620b of the exit surface 620. In Fig. 18, La indicates an example of a light ray that travels through the optical unit 600 and is emitted from the exit surface 620. The light distribution formed by the multiple projected light beams L61, L62 is adjusted by individually controlling the lighting of the multiple light sources 61, 62 (for example, by on-off control or dimming control).

[0120] Fig. 19(A) is a front view showing the light source unit 60 of the headlight device 6, and Figs. 19(B) and (C) are diagrams showing an example of an illumination range divided into two segments. The surfaces of the light sources 61 and 62 facing the +z-axis direction are light-emitting surfaces 61a and 62a. The light source unit 60 includes a plurality of light-emitting surfaces 61a and 62a. The light-emitting surfaces 61a and 62a are arranged, for example, on the same plane (i.e., a plane parallel to the xy plane). In the sixth embodiment, the light-emitting surfaces 61a and 62a are arranged in the x-axis direction.

[0121] The optical unit 600 is located in the +z-axis direction of the light source unit 60. A plurality of light beams emitted from the light emitting surfaces 61a, 62a of the light source unit 60 are incident on the optical unit 600. The optical unit 600 projects projection light beams L61, L62 consisting of a plurality of segments forward (in the +z-axis direction).

[0122] The incident surface 610 of the optical section 600 does not include, for example, a region that collects the light emitted from the light source section 60. However, the optical section 600 may include a light collecting region similar to that in the second embodiment.

[0123] The interval between the multiple segments of the projected light L61, L62 is determined by the degree of eccentricity of the optical axis A620a of the projection area 620a of the emission surface 620 with respect to the optical axes A61, A62 of the light sources 61, 62 and the size of the interval between the light sources 61, 62.

[0124] As shown in Fig. 19(C), it is desirable for the ends of adjacent segments of projected light to touch with some overlap. The optical axis A620a of the projection area 620a of the exit surface 620 is decentered so that the boundaries of the segments touch (including partial overlap) in the light distribution.

[0125] As described above, according to the sixth embodiment, optical unit 600 is configured by a single optical element, and therefore the focal position of exit surface 620 with respect to entrance surface 610 is fixed. Therefore, the influence of variation in the position of optical unit 600 on the light distribution is small.

[0126] In addition, by changing the parameters of the distance between adjacent light sources 61, 62 and the degree of eccentricity of the optical axis A620a of the exit surface 620 relative to the optical axes A61, A62 of the light sources 61, 62, the size of the distance between the segments can be precisely designed.

[0127] Except for the above, the sixth embodiment is the same as any one of the first to fifth embodiments. [Explanation of symbols]

[0128] 1 to 6 Headlamp device, 10, 20, 30, 40, 50, 60 Light source unit, 11 to 14, 21 to 24, 31, 32, 41 to 44, 51 to 54, 61, 62 Light source, 11a to 14a, 21a to 24a, 31a, 32a, 41a to 44a, 51a to 54a, 61a, 62a Light emitting surface, 100, 200, 300, 400, 500, 600 Optical unit (lens), 110, 210, 310, 410, 510, 610 Incident surface, 110a, 110b, 210a, 310a, 410a, 410b, 510a Light collecting area, 120, 220, 320, 420, 520, 620 Exit surface, 120a, 120b, 220a, 320a, 420a, 420b, 520a, 620a projection area, 340, 440, 540, 740 shade (light blocking member), 341, 342, 441-444, 541-544, 741-744 opening, A11-A14, A21-A24, A31, A32, A41-A44, A51-A54, A61, A62 optical axis (optical axis of light source), A110a, A110b, A210a, A310a, A410a, A410b, A510a optical axis (optical axis of light collecting area of ​​entrance surface), A120a, A120b, A220a, A320a, A420a, A420b, A520a, A620a Optical axis (optical axis of the projection area of ​​the exit surface), L11~L14, L21~L24, L31, L32, L41~L44, L51~L54, L61, L62, L71~L74 Projected light.

Claims

1. A light source unit having a plurality of light sources; a single optical unit having an incident surface and an exit surface, in which a plurality of light beams emitted from the light emitting surfaces of the plurality of light sources are incident on the incident surface, and the incident plurality of light beams are projected from the exit surface as a plurality of projected light beams to form a light distribution by the plurality of projected light beams; a structure for limiting the size of a luminous flux diameter of each of the plurality of light beams emitted from the light emitting surfaces of the plurality of light sources; A headlamp device comprising:

2. The entrance surface of the optical unit includes at least one light collecting area having a light collecting function.

2. The headlamp device according to claim 1 .

3. The structure includes a shade disposed between the light-emitting surface and the light-receiving surface, the shade having a plurality of openings for passing the light beams emitted from the light-emitting surface.

3. The headlamp device according to claim 2.

4. The shape of the plurality of openings is rectangular or has a shape whose width gradually narrows in a predetermined direction.

4. The headlamp device according to claim 3.

5. The area of ​​an incidence region of the incident light among the plurality of lights that passes through any one of the plurality of openings and strikes the incidence surface is The area of ​​the light emitting surface of the light source corresponding to the incident light among the plurality of light sources is smaller than that of the light emitting surface of the light source corresponding to the incident light, 5. The headlamp device according to claim 4.

6. The light emitting surfaces of the plurality of light sources are arranged on the same plane.

6. The headlamp device according to claim 5.

7. the at least one light collecting region has a convex portion protruding toward the light source portion and having an apex extending in a predetermined extension direction; The cross-sectional shape of the at least one light collecting region taken in a direction perpendicular to the extending direction is the same shape independent of the position in the extending direction.

7. The headlamp device according to claim 6.

8. the at least one light collecting region has a convex portion protruding toward the light source portion and having an apex extending in a predetermined direction; a profile of the at least one light collecting region is different on one side and the other side across the apex of the convex portion; The headlamp device according to claim 7.

9. The plurality of light beams emitted from the light emitting surfaces of the plurality of light sources pass through two of the plurality of optical surfaces of the optical unit and are projected as the plurality of projection light beams.

9. The headlamp device according to claim 1,

10. The exit surface of the optical unit has at least one projection area that is an area having a projection function.

10. The headlamp device according to claim 9.

11. The plurality of light beams emitted from the light emitting surfaces of the plurality of light sources are projected onto individual illumination regions via the optical unit. The headlamp device according to claim 10 .

Images