Light source distribution element for headlight device, and headlight module

Abstract

A light source distribution element (100) for a headlight device comprises: an incident unit (110) to which light from a light source (1) is inputted and which has three or more joining surfaces (111) to (115) located along one direction on a plane orthogonal to the optical axis of the light source (1); and three or more light-guiding units (121) to (125) that each have a rectangular cross section and each have a pair of opposed surfaces facing each other in another direction orthogonal to the one direction on the plane orthogonal to the optical axis of the light source (1), that have emission surfaces (121a) to (125a) corresponding to the plurality of joining surfaces (111) to (115) of the incident unit (110), respectively, and that guide light from the corresponding joining surfaces (111) to (115) to the corresponding emission surfaces (121a) to (125a). Among the plurality of light-guiding units (121) to (125), the pairs of opposed surfaces, at which the emission surfaces (122a), (123a) are located, of the light-guiding units (122), (123) on one end side in another direction with respect to the light source (1) have pairs of reflection surfaces (122b), (122c), (123b), (123c) inclined with respect to the optical axis of the light source (1), on the one end side. Among the plurality of light-guiding units (121) to (125), the pairs of opposed surfaces, at which the emission surfaces (124a), (125a) are located, of the light-guiding units (124), (125) on the other end side in the other direction with respect to the light source (1) have pairs of reflection surfaces (124b), (124c), (125b), (125c) inclined with respect to the optical axis of the light source (1), on the other end side.

Description

Light source distribution element for headlamp device and headlamp module

[0001] The present disclosure relates to a light source distribution element and a headlight module used in a headlight device that illuminates the area ahead of a vehicle body.

[0002] There is a demand for headlight devices that illuminate the area ahead of a vehicle, particularly low-beam headlights and high-beam headlights, to be thin and have improved light utilization efficiency. Patent Document 1 proposes a light source distribution element for a headlight device that has a simplified structure and is compact without sacrificing light utilization efficiency.

[0003] The light source distribution element for a headlamp device proposed in Patent Document 1 includes a first light guiding portion located between a first bonding surface of the incident portion and a first exit portion, and guiding light from the first bonding surface of the incident portion to the first exit portion, and a second light guiding portion located between a second bonding surface of the incident portion and the second exit portion, and having a first reflecting surface formed on one of the opposing side surfaces in the other direction and a second reflecting surface formed on the other of the opposing side surfaces in the other direction, and reflecting the light from the second bonding surface of the incident portion by the first reflecting surface and the second reflecting surface to guide it to the second exit portion. The light source distribution element for a headlamp device proposed in Patent Document 1 has a simple structure and can be made smaller without reducing light utilization efficiency.

[0004] Patent No. 7,031,087

[0005] There is a demand for light source distribution elements and headlight modules with even lower heights for vehicle headlight devices, and the present disclosure has been made in response to such demands, with the objective of obtaining a light source distribution element for a headlight device that has a simplified structure and is even smaller without reducing light utilization efficiency.

[0006] The light source distribution element for a headlamp device according to the present disclosure comprises an entrance section into which light from a light source is incident, the entrance section having three or more bonding surfaces positioned along one direction in a plane perpendicular to the optical axis of the light source, and three or more light guiding sections, each having a rectangular cross-sectional shape with a pair of opposing surfaces facing one direction in the plane perpendicular to the optical axis of the light source and another direction perpendicular to the one direction in the plane perpendicular to the optical axis of the light source, each having an exit surface corresponding to one of the plurality of bonding surfaces of the entrance section, and each guiding light from the corresponding bonding surface to the corresponding exit surface, wherein of the plurality of light guiding sections, the pair of opposing surfaces of the light guiding section whose exit surface is positioned at one end side in the other direction relative to the light source has a pair of reflective surfaces on one end side that are inclined with respect to the optical axis of the light source, and the pair of opposing surfaces of the light guiding section whose exit surface is positioned at the other end side in the other direction relative to the light source has a pair of reflective surfaces on the other end side that are inclined with respect to the optical axis of the light source.

[0007] According to the present disclosure, the structure can be simplified and further miniaturized without reducing the light utilization efficiency.

[0008] 1 is a perspective view showing a headlight module according to a first embodiment, as seen from above on the right side; FIG. 2 is a perspective view showing a headlight module according to a first embodiment, as seen from below on the left side; FIG. 3 is a front view showing a headlight module according to a first embodiment; FIG. 4 is a top view showing a headlight module according to a first embodiment; FIG. 5 is a bottom view showing a headlight module according to a first embodiment; FIG. 6 is a side view showing a headlight module according to a first embodiment; FIG. 7 is a front view showing a cross section of a portion of an incident portion of a headlight module according to a first embodiment; FIG. 8 is a diagram showing an illuminance distribution at a joint surface at an incident portion of a headlight module according to a first embodiment; FIG. 9 is a perspective view showing a luminous flux in a headlight module according to a first embodiment, as seen from above on the right side; FIG. 10 is a perspective view showing a headlight module according to a second embodiment, as seen from above on the right side; FIG. 11 is a perspective view showing a headlight module according to a second embodiment, as seen from below on the left side; FIG. 12 is a front view showing a headlight module according to a second embodiment; FIG. 13 is a top view showing a headlight module according to a second embodiment; FIG. 14 is a bottom view showing a headlight module according to a second embodiment; FIG. 15 is a side view showing a headlight module according to a second embodiment; 1 is a perspective view showing a light beam in a headlight module according to a second embodiment, as viewed from above on the right side; FIG. 2 is a perspective view showing a light beam in a headlight module according to a second embodiment, as viewed from below on the left side; FIG. 3 is a perspective view showing a headlight module according to a third embodiment, as viewed from above on the right side; FIG. 4 is a perspective view showing a headlight module according to a third embodiment, as viewed from below on the left side; FIG. 5 is a front view showing a headlight module according to a third embodiment; FIG. 6 is a top view showing a headlight module according to a third embodiment; FIG. 7 is a bottom view showing a headlight module according to a third embodiment; FIG. 8 is a side view showing a headlight module according to a third embodiment; FIG. 9 is an enlarged perspective view showing a light source distribution element and a light collecting optical unit in a headlight module according to a third embodiment, as viewed from above on the right side; FIG. 10 is an enlarged perspective view showing a light source distribution element and a light collecting optical unit in a headlight module according to a third embodiment, as viewed from below on the left side; FIG. 11 is a perspective view showing a headlight module according to a fourth embodiment, as viewed from above on the right side; FIG. 12 is a perspective view showing a headlight module according to a fourth embodiment, as viewed from below on the left side; FIG. 13 is a front view showing a headlight module according to a fourth embodiment;10A and 10B are a top view and a bottom view, respectively, of a headlight module according to a fourth embodiment of the present invention, and a side view, respectively, of a headlight module according to a fourth embodiment of the present invention.

[0009] Embodiment 1. A light source distribution element 100 for a headlight device (hereinafter simply referred to as the light source distribution element 100) and a headlight module according to embodiment 1 will be described with reference to Figures 1 to 10. The headlight module is used in a headlight device that satisfies a predetermined light distribution pattern stipulated by road traffic regulations and the like, and illuminates the area ahead of an automobile, a motorcycle, or a motorized tricycle known as a gyro (a scooter or motorized bicycle with three wheels, one in front and two in the rear, on a single axle). The headlight device has a low beam and a high beam.

[0010] The headlight module according to the first embodiment can be used for both low beam and high beam, but is particularly suitable for use in low beam. In the following description, an example in which the headlight module is applied to the low beam of an automotive headlight device will be described. Note that when applied to the low beam of an automotive headlight device, the headlight module may be one, or multiple headlight modules may be arranged in parallel in the left-right direction.

[0011] Before describing the light source distribution element 100 and the headlamp module in detail, the terms used in this disclosure will be explained. Light distribution refers to the spatial luminous intensity distribution of a light source. In other words, it is the spatial distribution of light emitted from the light source. Luminous intensity indicates the intensity of light emitted by a light emitter, and is calculated by dividing the luminous flux passing through a small solid angle in a certain direction by that small solid angle.

[0012] Road traffic regulations require that the low beams of automobile headlamp devices and motorcycle headlamp devices have a horizontally elongated light distribution pattern that is narrow in the vertical direction, and that the upper light boundary line of the light distribution pattern, i.e., the cut-off line, be clear so as not to dazzle drivers of oncoming vehicles. The light distribution pattern refers to the shape of the luminous flux and the light intensity distribution resulting from the direction of light emitted from a light source 1. The light distribution pattern is also used to mean the illuminance pattern on an illuminated surface. The light distribution is the distribution of light intensity relative to the direction of light emitted from a light source. The light distribution is also used to mean the illuminance distribution on an illuminated surface.

[0013] The required clear cutoff line means that the upper side of the cutoff line, i.e., the outside of the light distribution pattern, is dark, and the lower side of the cutoff line, i.e., the inside of the light distribution pattern, is bright.

[0014] The cutoff line is a dividing line between light and dark that is created when the light of a headlight device is projected onto a wall or screen, and is the dividing line at the top of the light distribution pattern. In other words, the cutoff line is the boundary line between light and dark at the top of the light distribution pattern. It is the boundary line between the bright area of ​​light at the top of the light distribution pattern, i.e., the inside of the light distribution pattern, and the dark area, i.e., the outside of the light distribution pattern. The cutoff line is a term used when adjusting the irradiation direction of a passing headlight device. Passing headlight devices are also called low beams.

[0015] Low beams are required to have maximum illuminance in the area below the cutoff line. This area of ​​maximum illuminance is called the high illuminance area. The area below the cutoff line refers to the upper part of the light distribution pattern, which corresponds to the part of a headlamp device that illuminates distant objects. To achieve a clear cutoff line, there must be no significant chromatic aberration or blurring in the cutoff line. Blurring in the cutoff line means that the cutoff line is unclear.

[0016] In the case of low beam headlight devices for automobiles, the cutoff line has a stepped shape with a rising line. In the case of low beam headlight devices for motorcycles, the cutoff line is a horizontal straight line in the left-right direction of the vehicle, and the light distribution pattern is brightest below the cutoff line, i.e., in the area inside the light distribution pattern. In addition, because headlight devices are placed in front of the vehicle, design is important, and there is a demand for headlight devices with increased design freedom. If a headlight device is made thin in the vertical direction of the vehicle in order to improve design, light utilization efficiency will be reduced.

[0017] The light source distribution element 100 and headlamp module according to the first embodiment are made smaller without reducing light utilization efficiency by reducing the thickness in the vertical direction of the light exit surface of the light source distribution element 100 and focusing on Abbe's invariant (Abbe's sine condition or the law of conservation of etendue). That is, by providing three or more, preferably five, exit surfaces for the light source distribution element 100, the length of one side of the exit surface of the light source distribution element 100, which serves as an apparent light source, can be made shorter, thereby achieving miniaturization.

[0018] In the following description, XYZ coordinates will be used for ease of explanation. The left-right direction of the vehicle is the X-axis direction. With respect to the front of the vehicle, the right side is the + direction of the X-axis, and the left side is the - direction of the X-axis. Here, "forward" refers to the direction in which the vehicle is traveling. In other words, "forward" refers to the direction in which the headlight device emits light. In the light-source distribution element 100 and headlight module according to embodiment 1, the X-axis direction is the other direction, with one end side being the - direction (right side) and the other end side being the + direction (left side). Note that although one end side is defined as the right side and the other end side as the left side, this is specified for convenience of explanation, and one end side may be defined as the left side and the other end side as the right side.

[0019] The up-and-down direction of the vehicle is the Y-axis direction. The upper side is the + direction of the Y-axis, and the lower side is the - direction of the Y-axis. The upper side is the direction toward the sky, and the lower side is the direction toward the ground (road surface, etc.). The traveling direction of the vehicle is the Z-axis direction. The traveling direction is the + direction of the Z-axis, and the opposite direction is the - direction of the Z-axis. The + direction of the Z-axis is called the forward direction, and the - direction of the Z-axis is called the backward direction. In other words, the + direction of the Z-axis is the direction in which the headlight emits light. In the light-source distribution element 100 and headlight module according to embodiment 1, the Z-axis direction is one direction, with one end side being the + direction, which is the forward direction when used for an automobile, and the other end side being the - direction, which is the backward direction when used for an automobile.

[0020] The Z-X plane is a plane parallel to the road surface. The road surface is usually considered to be a horizontal plane, that is, a plane perpendicular to the direction of gravity. However, the road surface may be inclined relative to the direction of travel of the vehicle due to an uphill or downhill slope, etc.

[0021] In addition, although it is rare for a typical road surface to be inclined left or right with respect to the vehicle's traveling direction, that is, in the width direction of the road, the road surface may be inclined left or right. Therefore, although the horizontal plane, which is a plane parallel to the road surface, is not necessarily a plane perpendicular to the direction of gravity, the following explanation will be given assuming that the horizontal plane is a plane perpendicular to the direction of gravity, and the Z-X plane is a plane perpendicular to the direction of gravity.

[0022] The light source distribution element 100 and the headlight module will be described in detail below. As shown in Figures 1 to 6, the headlight module includes the light source distribution element 100 and the light distribution forming unit 200. In addition to the headlight module, the headlight device also includes a light source 1. The light source 1 emits light to illuminate the area ahead of the vehicle. The light source 1 is disposed on the - side of the Y axis of the light source distribution element 100, and emits light in the + direction of the Y axis. The optical axis of the light source 1 is an axis along the Y axis direction.

[0023] The light source 1 has a rectangular light output surface that emits light to the front. The light source 1 is either a tube light source such as an incandescent lamp, a halogen lamp, or a fluorescent lamp, or a semiconductor light source such as a light emitting diode (LED) or a laser diode (LD).

[0024] Carbon dioxide (CO ２ From the viewpoint of reducing the burden on the environment by suppressing emissions of CO₂ and fuel consumption, it is preferable to use semiconductor light sources, which have higher luminous efficiency and directionality than halogen lamps and allow for a smaller and lighter optical system. The headlamp device of the present disclosure uses an LED, which is one type of semiconductor light source.

[0025] In the first embodiment, the light source distribution element 100 and the light distribution forming unit 200 are integrally formed from a transparent material, and the boundary surface between the components is not a physical boundary surface but a virtual surface. However, when the light source distribution element 100 is used alone, the exit surfaces 121a to 125a of the light source distribution element 100 are physically exposed surfaces, and when used as a headlamp module, the exit surfaces 121a to 125a of the light source distribution element 100 are coupled to the light distribution forming unit 200 when assembled with the light distribution forming unit 200.

[0026] In the first embodiment, the headlamp module is manufactured by injection molding and is made of a transparent material filled with a refractive material. The material from which the headlamp module is manufactured is preferably highly transparent from the viewpoint of light utilization efficiency, and also has excellent heat resistance because the light source distribution element 100 is disposed immediately after the light source 1. For example, a transparent resin such as glass or silicone is preferable. Specifically, suitable transparent resins include acrylic resin (especially PMMA: polymethyl methacrylate), polycarbonate (PC), and cycloolefin resin.

[0027] The light-source distribution element 100 includes an incident section 110 and a collective light-guiding section 120. As shown in Figure 7, the incident section 110 is a collimator that has a conical shape with a lens 116 at its apex, and the bottom surface of the cone serves as the joint surface of the collective light-guiding section 120. The joint surface has a diameter of, for example, 20 mm. In the incident section 110, light emitted from the light source 1 is incident on the lens 116, and the incident light is guided to the joint surface as parallel light, ideally as collimated light.

[0028] Of the light emitted from light source 1, light rays with small emission angles are incident on lens 116 and then directly guided to the conical bottom surface of incident unit 110 (the joint surface of collective light-guiding unit 120). On the other hand, of the light emitted from light source 1, light rays with large emission angles are incident on lens 116 and then reflected by reflecting surface 117 and guided to the conical bottom surface of incident unit 110. The light rays directly guided from lens 116 and the light rays reflected and guided by reflecting surface 117 are guided as parallel beams to the joint surface of collective light-guiding unit 120.

[0029] 8 shows the illuminance distribution at the joint surface of the light-source distribution element 100 when an LED that emits light elongated in the X-axis direction is used as the light source 1. In the first embodiment, the joint surface of the light-source distribution element 100 is divided into equal lengths, i.e., equal widths, along one direction in a plane perpendicular to the optical axis of the light source 1, i.e., along the Z-axis, as shown in FIG. 8 , and includes a first joint surface 111 located at the center, a second joint surface 112 and a third joint surface 113 located in this order from the center to one end in that direction, i.e., on the + side of the Z-axis, and a fourth joint surface 114 and a fifth joint surface 115 located in this order from the center to the other end in that direction, i.e., on the - side of the Z-axis. The first to fifth joint surfaces 111 to 115 are imaginary surfaces that indicate boundaries with the collective light-guiding section 120.

[0030] Collective light-guiding section 120 has a joint surface that joins with the joint surface of incident section 110. Collective light-guiding section 120 has five exit surfaces, namely, first exit surface 121 a to fifth exit surface 125 a, that are arranged in a plane parallel to the joint surface of incident section 110, i.e., the Z-X plane, without overlapping in the Z-axis direction and the X-axis direction, and guides light from the joint surface of incident section 110 to first exit surface 121 a to fifth exit surface 125 a.

[0031] Along the X-axis, the fifth exit surface 125a, the fourth exit surface 124a, the first exit surface 121a, the second exit surface 122a, and the third exit surface 123a are arranged in this order from the other end. Along the Z-axis, the fifth exit surface 125a, the fourth exit surface 124a, the first exit surface 121a, the second exit surface 122a, and the third exit surface 123a are arranged in this order from the other end. The first exit surface 121a to the fifth exit surface 125a are rectangular, and each has the same length W in the X-axis direction and the same length in the Z-axis direction. Note that the length of each exit surface in the X-axis direction may be different.

[0032] The collective light-guiding section 120 includes a first light-guiding section 121 to a fifth light-guiding section 125. Each of the first light-guiding section 121 to the fifth light-guiding section 125 has a pair of opposing surfaces that face each other parallel to the X-axis direction in the Z-X plane, which is a plane orthogonal to the optical axis of the light source 1, i.e., the Y-axis, and is a columnar body with a rectangular Z-X cross section. The first light-guiding section 121 has a first light-emitting surface 121a and guides light from the first joint surface 111 of the incident section 110 to the first light-emitting surface 121a.

[0033] The first light guiding unit 121 has a pair of opposing surfaces parallel to the Y axis, and is formed integrally with the incident unit 110, standing upright from the first bonding surface 111 of the incident unit 110. The distance between the pair of opposing surfaces along the X axis direction is W. The first light guiding unit 121 has a rectangular parallelepiped shape that linearly connects the first bonding surface 111 of the incident unit 110 to the first exit surface 121a. As shown in FIGS. 9 and 10 as a light beam L1, the first light guiding unit 121 causes light from the first bonding surface 111 of the incident unit 110 to travel straight along the Y axis to the first exit surface 121a.

[0034] Second light guiding unit 122 has second exit surface 122a and guides light from second bonding surface 112 of incident unit 110 to second exit surface 122a. A pair of opposing surfaces in second light guiding unit 122 has a pair of reflecting surfaces, that is, first reflecting surface 122b located toward the center in the X-axis direction and second reflecting surface 122c located toward one end. In the first embodiment, first reflecting surface 122b and second reflecting surface 122c are each the entire surface of the pair of opposing surfaces.

[0035] The second light guiding unit 122 is formed integrally with the incident unit 110 such that the first reflecting surface 122b and the second reflecting surface 122c are each inclined at 45 degrees toward one end with respect to the second bonding surface 112. In other words, the second light guiding unit 122 is formed integrally with the incident unit 110 such that the first reflecting surface 122b and the second reflecting surface 122c are each inclined at 45 degrees toward one end with respect to the optical axis of the light source 1.

[0036] The distance along the X-axis direction between first reflecting surface 122b and second reflecting surface 122c is W. Second light guiding unit 122 has a columnar shape, with the distance along the X-axis direction between first reflecting surface 122b and second reflecting surface 122c linearly connecting second bonding surface 112 of incident unit 110 to second exit surface 122a at an angle of 45 degrees toward one end with respect to second bonding surface 112.

[0037] Note that 45 degrees does not refer to an exact angle, but rather refers to a range of 45 degrees ±α, taking into account a design margin of ±α. In the following description, 45 degrees refers to a range of 45 degrees ±α. Furthermore, the tilt angle of the reflective surface does not need to be limited to 45 degrees. Since it is desirable for the reflective surface to be a total reflective surface, the ideal tilt angle is approximately 45 degrees. However, in the case of a mirror surface formed by metal vapor deposition or the like, the tilt angle can be freely designed. However, it is desirable for the reflective surface to function as a total reflective surface. This is because a total reflective surface has a higher reflectivity than a mirror surface and contributes to improving light utilization efficiency. Furthermore, eliminating the mirror vapor deposition process simplifies the manufacturing process of the light source distribution element 100, contributing to reducing the manufacturing cost of the light source distribution element 100.

[0038] 9 and 10 , the second light guiding unit 122 totally reflects the light from the second bonding surface 112 of the incident unit 110 to the second reflecting surface 122c, which then totally reflects the light to the second exit surface 122a, thereby guiding the light to the second exit surface 122a, as shown as light beam L2 in Fig. 9 and 10 . The second light guiding unit 122 finally guides the light from the second bonding surface 112 of the incident unit 110 to the second exit surface 122a as parallel light along the Y axis.

[0039] The third light guiding unit 123 has a third exit surface 123a, and guides light from the third bonding surface 113 of the incident unit 110 to the third exit surface 123a. A pair of opposing surfaces of the third light guiding unit 123 has a pair of reflecting surfaces, that is, a third reflecting surface 123b located on the central side in the X-axis direction and a fourth reflecting surface 123c located on one end side.

[0040] The third light guiding unit 123 is formed integrally with the incident unit 110 such that the third reflecting surface 123b and the fourth reflecting surface 123c are each inclined at 45 degrees toward one end with respect to the third bonding surface 113. In other words, the third light guiding unit 123 is formed integrally with the incident unit 110 such that the third reflecting surface 123b and the fourth reflecting surface 123c are each inclined at 45 degrees toward one end with respect to the optical axis of the light source 1.

[0041] The distance along the X-axis direction between third reflecting surface 123b and fourth reflecting surface 123c is 2W, which is twice W. Third light guiding unit 123 has a length along the X-axis direction of 2W and a columnar shape inclined 45 degrees toward one end with respect to third bonding surface 113. Fourth reflecting surface 123c of third light guiding unit 123 is located away from the position of second reflecting surface 122c of second light guiding unit 122 toward one end in the other direction by the length W of third emission surface 123a in the other direction.

[0042] 9 and 10 , the third light guiding unit 123 totally reflects the light from the third bonding surface 113 of the incident unit 110 to the fourth reflecting surface 123c, which then totally reflects the light to the third exit surface 123a, thereby guiding the light to the third exit surface 123a, as shown as light beam L3 in Fig. 9 and 10 . The third light guiding unit 123 finally guides the light from the third bonding surface 113 of the incident unit 110 to the third exit surface 123a as parallel light along the Y axis.

[0043] Third reflecting surface 123b of third light guiding unit 123 is continuous with first reflecting surface 122b of second light guiding unit 122 on one end side in the Z-axis direction. Third light guiding unit 123 is formed integrally with second light guiding unit 122 from third bonding surface 113 of incident unit 110 to the position of first reflecting surface 122b of second light guiding unit 122 to the position of second reflecting surface 122c.

[0044] The fourth reflecting surface 123c of the third light guiding unit 123 is located at a position away from the position of the second reflecting surface 122c of the second light guiding unit 122 toward one end in the X-axis direction by the length W of the third exit surface 123a in the X-axis direction. That is, the distance along the X-axis direction between the third reflecting surface 123b and the fourth reflecting surface 123c is twice the distance W along the X-axis direction between the first reflecting surface 122b and the second reflecting surface 122c of the second light guiding unit 122, i.e., 2W.

[0045] The third light guiding unit 123 has a shape in which two second light guiding units 122 are arranged in parallel in the X-axis direction. The third light guiding unit 123 is integrally formed with the second light guiding unit 122 from the third reflecting surface 123b of the third light guiding unit 123 to the second reflecting surface 122c of the second light guiding unit 122.

[0046] A common light guiding section having a shape in which two second light guiding sections 122 are arranged in parallel in the Z-axis direction extends from the position of first reflecting surface 122b to the position of second reflecting surface 122c of second light guiding section 122 and from the position of third reflecting surface 123b of third light guiding section 123 to the position of second reflecting surface 122c of second light guiding section 122. From the position of first reflecting surface 122b to the position of second reflecting surface 122c of second light guiding section 122, the boundary surface between second light guiding section 122 and third light guiding section 123 is not a physical boundary surface but a virtual surface.

[0047] The fourth light guiding unit 124 has a fourth exit surface 124a and guides light from the fourth bonding surface 114 of the incident unit 110 to the fourth exit surface 124a. A pair of opposing surfaces in the fourth light guiding unit 124 has a pair of reflecting surfaces, that is, a fifth reflecting surface 124b located toward the center in the X-axis direction and a sixth reflecting surface 124c located toward the other end. In the first embodiment, the fifth reflecting surface 124b and the sixth reflecting surface 124c are each the entire surface of the pair of opposing surfaces.

[0048] The fourth light guiding unit 124 is formed integrally with the incident unit 110 such that the fifth reflecting surface 124b and the sixth reflecting surface 124c are each inclined at 45 degrees toward the other end with respect to the fourth bonding surface 114. In other words, the fourth light guiding unit 124 is formed integrally with the incident unit 110 such that the fifth reflecting surface 124b and the sixth reflecting surface 124c are each inclined at 45 degrees toward one end with respect to the optical axis of the light source 1.

[0049] The distance between the fifth reflecting surface 124b and the sixth reflecting surface 124c along the X-axis direction is W. The fourth light guiding unit 124 has a columnar shape that connects the fourth bonding surface 114 of the incident unit 110 to the fourth exit surface 124a in a straight line at an angle of 45 degrees toward the other end with respect to the fourth bonding surface 114, and the distance between the fifth reflecting surface 124b and the sixth reflecting surface 124c along the X-axis direction is W.

[0050] 9 and 10 , the fourth light guiding unit 124 totally reflects light from the fourth bonding surface 114 of the incident unit 110 to the sixth reflecting surface 124c, which then totally reflects the light to the fourth exit surface 124a, thereby guiding the light to the fourth exit surface 124a. The fourth light guiding unit 124 finally guides the light from the fourth bonding surface 114 of the incident unit 110 to the fourth exit surface 124a as parallel light along the Y axis. The shape of the fourth light guiding unit 124 is in a line-symmetric relationship with the shape of the second light guiding unit 122 with respect to the Y axis.

[0051] Fifth light guiding unit 125 has fifth exit surface 125a, and guides light from fifth bonding surface 115 of incident unit 110 to fifth exit surface 125a. A pair of opposing surfaces of fifth light guiding unit 125 has a pair of reflecting surfaces, that is, seventh reflecting surface 125b located on the central side in the X-axis direction and eighth reflecting surface 125c located on the other end side.

[0052] The fifth light guiding unit 125 is formed integrally with the incident unit 110 such that the seventh reflecting surface 125b and the eighth reflecting surface 125c are each inclined at 45 degrees toward the other end with respect to the fifth bonding surface 115. In other words, the fifth light guiding unit 125 is formed integrally with the incident unit 110 such that the seventh reflecting surface 125b and the eighth reflecting surface 125c are each inclined at 45 degrees toward one end with respect to the optical axis of the light source 1.

[0053] The distance between seventh reflecting surface 125b and eighth reflecting surface 125c along the X-axis direction is 2W, which is twice W. Fifth light guiding unit 125 has a length of 2W along the X-axis direction and a columnar shape inclined 45 degrees toward the other end with respect to fifth bonding surface 115. Eighth reflecting surface 125c of fifth light guiding unit 125 is located at a position away from the position of sixth reflecting surface 124c of fourth light guiding unit 124 toward the other end in the other direction by the length W of fifth emission surface 125a in the other direction.

[0054] 9 and 10 , the fifth light guiding unit 125 totally reflects the light from the fifth bonding surface 115 of the incident unit 110 to the eighth reflecting surface 125c, which then totally reflects the light to the fifth exit surface 125a, thereby guiding the light to the fifth exit surface 125a, as shown as light beam L5 in Fig. 9 and 10 . The fifth light guiding unit 125 finally guides the light from the fifth bonding surface 115 of the incident unit 110 to the fifth exit surface 125a as parallel light along the Y axis.

[0055] Seventh reflecting surface 125b of fifth light guiding unit 125 is continuous with the other end in the Z-axis direction of fifth reflecting surface 124b of fourth light guiding unit 124. Fifth light guiding unit 125 is formed integrally with fourth light guiding unit 124 from fifth bonding surface 115 of incident unit 110 to the position of fifth reflecting surface 124b to the position of sixth reflecting surface 124c of fourth light guiding unit 124.

[0056] The eighth reflecting surface 125c of the fifth light guiding unit 125 is located at a position away from the sixth reflecting surface 124c of the fourth light guiding unit 124 by the length W in the X-axis direction of the fifth exit surface 125a toward the other end in the X-axis direction. That is, the distance along the X-axis direction between the seventh reflecting surface 125b and the eighth reflecting surface 125c is twice the distance W along the X-axis direction between the fifth reflecting surface 124b and the sixth reflecting surface 124c of the fourth light guiding unit 124, i.e., 2W.

[0057] The fifth light guiding unit 125 has a shape in which two fourth light guiding units 124 are arranged in parallel in the X-axis direction. The portion from the seventh reflecting surface 125 b of the fifth light guiding unit 125 to the sixth reflecting surface 124 c of the fourth light guiding unit 124 is formed integrally with the fourth light guiding unit 124. The portion from the fifth reflecting surface 124 b to the sixth reflecting surface 124 c of the fourth light guiding unit 124 and the portion from the seventh reflecting surface 125 b of the fifth light guiding unit 125 to the sixth reflecting surface 124 c of the fourth light guiding unit 124 form a common light guiding unit in which two fourth light guiding units 124 are arranged in parallel in the Z-axis direction.

[0058] The boundary between the fourth light guiding unit 124 and the fifth light guiding unit 125 is not a physical boundary but a virtual surface from the position of the fifth reflecting surface 124b to the position of the sixth reflecting surface 124c of the fourth light guiding unit 124. The shape of the fifth light guiding unit 125 and the shape of the third light guiding unit 123 are in a line-symmetric relationship with respect to the Y axis.

[0059] In the light source distribution element 100 configured in this manner, by providing three or more, preferably five, exit surfaces of the collective light guide section 120, it is possible to reduce the height to the exit surface of the collective light guide section 120 without reducing the light utilization efficiency of the light from the light source 1. The apparent size of the light source is defined by "Abbe's invariant," which is determined by the product of the divergence angle in a certain direction of the light source and the length of the side of the light source in that direction. In other words, the height of the light source, that is, the length in the vertical direction, is defined as h ０ The vertical divergence angle of the light from the light source is θ0, and the vertical length of the exit surface, that is, the length of the vertical side, is h １ The vertical divergence angle of the light emitted from the exit surface is θ １ Then, h ０ ×sin θ ０ >h １ ×sin θ １ This becomes a relationship.

[0060] Therefore, by dividing the light beam from light source 1 into multiple beams, the apparent height of the light source can be reduced, and in the first embodiment, first light guiding unit 121 to fifth light guiding unit 125 divide the light from light source 1 collimated by incident unit 110 into five beams, so that the length of the side in the Z-axis direction of the exit surface of collective light guiding unit 120 can be reduced, and the length of the side in the Z-axis direction of first exit surface 121 a to fifth exit surface 125 a can be reduced. When light-source distribution element 100 according to the first embodiment is applied to a headlight module, the height of the projection surface can be reduced, and miniaturization can be achieved.

[0061] The light distribution forming unit 200 totally reflects light in the Y-axis direction from the exit surface of the collective light-guiding unit 120 in the light-source distribution element 100, which in the first embodiment are the first to fifth exit surfaces 121a to 125a, forward in the Z-axis direction, and guides the light to the projection surfaces, which in the first embodiment are the first to fifth projection surfaces 231a to 235a. The light distribution forming unit 200 includes a collective light-collecting optical unit 210, a collective light distribution unit 220, and a projection unit 230. The light distribution forming unit 200 is integrally formed from a transparent material.

[0062] The collective light-collecting optical unit 210 collects light from the exit surface of the collective light-guiding unit 120 downward and forward in the Z-axis direction by total reflection. The collective light-collecting optical unit 210 is formed integrally with the collective light-guiding unit 120. The collective light-collecting optical unit 210 includes a first light-collecting optical unit 211 to a fifth light-collecting optical unit 215. The first light-collecting optical unit 211 to the fifth light-collecting optical unit 215 are arranged along the X-axis in the order of the fifth light-collecting optical unit 215, the fourth light-collecting optical unit 214, the first light-collecting optical unit 211, the second light-collecting optical unit 212, and the third light-collecting optical unit 213 from the other end side.

[0063] The first focusing optical unit 211 has a bonding surface that bonds with the first emission surface 121a of the first light guide unit 121, a reflecting surface that faces the bonding surface, is inclined toward one end of the Z axis, i.e., forward, with respect to the bonding surface, and has a light focusing function, a pair of parallel opposing surfaces along the X axis, and a front surface that is located on the one end of the Z axis and serves as an exit port for light reflected by the reflecting surface. The length along the X axis of the bonding surface of the first focusing optical unit 211, the distance between the pair of opposing surfaces of the first focusing optical unit 211, and the length along the X axis of the front surface of the first focusing optical unit 211 are all W, which is the same as the length W of the first emission surface 121a in the X axis direction.

[0064] In the first focusing optical unit 211, the reflecting surface is a flat surface inclined forward at an angle of less than 45 degrees with respect to the bonding surface, and may have a curved surface depending on the application. The first focusing optical unit 211 reflects light from the first exit surface 121 a of the first light guiding unit 121 downward and forward in the Z-axis direction by the reflecting surface to focus the light. Note that in the first embodiment, the bonding surface of the first focusing optical unit 211 and the first exit surface 121 a of the first light guiding unit 121 are not physically bonded surfaces but are virtual surfaces.

[0065] The second focusing optical unit 212 has a bonding surface that bonds with the second emission surface 122a of the second light guide unit 122, a reflective surface that faces the bonding surface, is inclined toward one end of the Z axis, i.e., forward, with respect to the bonding surface, and has a light focusing function, a pair of parallel opposing surfaces along the X axis, and a front surface that is located on the one end of the Z axis and serves as an exit port for light reflected by the reflective surfaces. The length along the X axis of the bonding surface of the second focusing optical unit 212, the distance between the pair of opposing surfaces of the second focusing optical unit 212, and the length along the X axis of the front surface of the second focusing optical unit 212 are all W, which is the same as the length W of the second emission surface 122a in the X axis direction.

[0066] In the second focusing optical unit 212, the reflecting surface is a flat surface inclined forward at an angle of less than 45 degrees with respect to the bonding surface, and may have a curved surface depending on the application. The second focusing optical unit 212 reflects light from the second exit surface 122a of the second light guiding unit 122 downward and forward in the Z-axis direction by the reflecting surface to focus the light. Note that in the first embodiment, the bonding surface of the second focusing optical unit 212 and the second exit surface 122a of the second light guiding unit 122 are not physically bonded surfaces but are virtual surfaces.

[0067] The third focusing optical unit 213 has a bonding surface that bonds with the third exit surface 123a of the third light guide unit 123, a reflective surface that faces the bonding surface, is inclined downward toward one end of the Z axis, i.e., forward, with respect to the bonding surface, and has a light focusing function, a pair of parallel opposing surfaces along the X axis, and a front surface that is located on the one end of the Z axis and serves as an exit port for light reflected by the reflective surfaces. The length along the X axis of the bonding surface of the third focusing optical unit 213, the distance between the pair of opposing surfaces of the third focusing optical unit 213, and the length along the X axis of the front surface of the third focusing optical unit 213 are all W, which is the same as the length W of the third exit surface 123a in the X axis direction.

[0068] In the third light-collecting optical unit 213, the reflecting surface is a flat surface inclined forward at less than 45 degrees with respect to the bonding surface, and may have a curved surface depending on the application. The third light-collecting optical unit 213 reflects light from the third exit surface 123a of the third light-guiding unit 123 downward and forward in the Z-axis direction by the reflecting surface to collect the light. Note that in the first embodiment, the bonding surface of the third light-collecting optical unit 213 and the third exit surface 123a of the third light-guiding unit 123 are not physically bonded surfaces but are virtual surfaces.

[0069] The fourth focusing optical unit 214 has a bonding surface that bonds with the fourth emission surface 124a of the fourth light guide unit 124, a reflective surface that faces the bonding surface, is inclined downward toward one end of the Z axis, i.e., forward, with respect to the bonding surface, and has a light focusing function, a pair of parallel opposing surfaces along the X axis, and a front surface that is located on the one end of the Z axis and serves as an exit port for light reflected by the reflective surfaces. The length along the X axis of the bonding surface of the fourth focusing optical unit 214, the distance between the pair of opposing surfaces of the fourth focusing optical unit 214, and the length along the X axis of the front surface of the fourth focusing optical unit 214 are all W, which is the same as the length W of the fourth emission surface 124a in the X axis direction.

[0070] In the fourth focusing optical unit 214, the reflecting surface is a flat surface inclined forward at less than 45 degrees with respect to the bonding surface, and may have a curved surface depending on the application. The fourth focusing optical unit 214 reflects light from the fourth exit surface 124a of the fourth light guiding unit 124 downward and forward in the Z-axis direction by the reflecting surface to focus the light. Note that in the first embodiment, the bonding surface of the fourth focusing optical unit 214 and the fourth exit surface 124a of the fourth light guiding unit 124 are not physically bonded surfaces but are virtual surfaces.

[0071] The fifth focusing optical unit 215 has a bonding surface that bonds with the fifth exit surface 125a of the fifth light guide unit 125, a reflective surface that faces the bonding surface, is inclined toward one end of the Z axis, i.e., forward, with respect to the bonding surface, and has a light focusing function, a pair of opposing surfaces along the X axis, and a front surface that is located on the one end side of the Z axis and serves as an exit port for light reflected by the reflective surfaces. The length along the X axis of the bonding surface of the fifth focusing optical unit 215, the distance between the pair of opposing surfaces of the fifth focusing optical unit 215, and the length along the X axis of the front surface of the fifth focusing optical unit 215 are all W, which is the same as the length W of the fifth exit surface 125a in the X axis direction.

[0072] In the fifth focusing optical unit 215, the reflecting surface is a flat surface inclined forward and downward at an angle of less than 45 degrees with respect to the bonding surface, and may have a curved surface depending on the application. The fifth focusing optical unit 215 reflects light from the fifth exit surface 125a of the fifth light guiding unit 125 forward and downward in the Z-axis direction using the reflecting surface to focus the light. Note that in the first embodiment, the bonding surface of the fifth focusing optical unit 215 and the fifth exit surface 125a of the fifth light guiding unit 125 are not physically bonded surfaces but are virtual surfaces.

[0073] By making the reflective surfaces of each of the first focusing optical unit 211 to the fifth focusing optical unit 215 reflective surfaces having a focusing function, it is possible to easily form the complex light distribution required for a headlamp device.

[0074] The collective light distribution unit 220 guides the multiple light beams reflected and collected by the collective light collecting optical unit 210 to multiple projection surfaces, that is, first projection surface 231a to fifth projection surface 235a in the first embodiment. The collective light distribution unit 220 is formed integrally with the collective light collecting optical unit 210. The collective light distribution unit 220 includes first light distribution unit 221 to fifth light distribution unit 225. The first light distribution unit 221 to fifth light distribution unit 225 are arranged along the X axis in the order of fifth light distribution unit 225, fourth light distribution unit 224, first light distribution unit 221, second light distribution unit 222, and third light distribution unit 223 from the other end side, and are formed integrally. Adjacent light distribution units are not physically joined together.

[0075] First light distribution unit 221 guides light resulting from a luminous flux reflected and collected from the front surface of first light collection optical unit 211 to projection unit 230. The joint surface between first light distribution unit 221 and the front surface of first light collection optical unit 211 is not a physically joined surface but a virtual surface. The width along the X axis of first light distribution unit 221 is W, which is the same as the length W of first emission surface 121a in the X axis direction.

[0076] The second light distribution unit 222 guides light resulting from the luminous flux reflected and collected from the front surface of the second light collection optical unit 212 to the projection unit 230. The joint surface between the second light distribution unit 222 and the front surface of the second light collection optical unit 212 is not a physically joined surface but a virtual surface. The width along the X axis of the second light distribution unit 222 is W, which is the same as the length W of the second emission surface 122a in the X axis direction.

[0077] The third light distribution unit 223 guides light resulting from the luminous flux reflected and collected from the front surface of the third light collection optical unit 213 to the projection unit 230. The joint surface between the third light distribution unit 223 and the front surface of the third light collection optical unit 213 is not a physically joined surface but a virtual surface. The width along the X axis of the third light distribution unit 223 is W, which is the same as the length W of the third emission surface 123a in the X axis direction.

[0078] The fourth light distribution unit 224 guides light resulting from the luminous flux reflected and collected from the front surface of the fourth light collection optical unit 214 to the projection unit 230. The joint surface between the fourth light distribution unit 224 and the front surface of the fourth light collection optical unit 214 is not a physically joined surface but a virtual surface. The width along the X axis of the fourth light distribution unit 224 is W, which is the same as the length W of the fourth emission surface 124a in the X axis direction.

[0079] Fifth light distribution unit 225 guides light resulting from the luminous flux reflected and collected from the front surface of fifth light collection optical unit 215 to projection unit 230. The joint surface between fifth light distribution unit 225 and the front surface of fifth light collection optical unit 215 is not a physically joined surface but a virtual surface. The width along the X axis of fifth light distribution unit 225 is W, which is the same as the length W of fifth emission surface 125a in the X axis direction.

[0080] The projection unit 230 has a plurality of projection surfaces, first to fifth projection surfaces 231a to 235a in the first embodiment, and projects light guided as a luminous flux by the collective light distribution unit 220 from the plurality of projection surfaces. The projection unit 230 is formed integrally with the collective light distribution unit 220. The projection unit 230 includes a first to fifth projection lens 231 to 235. The first to fifth projection lenses 231 to 235 are arranged along the X axis in the order of the fifth projection lens 235, the fourth projection lens 234, the first projection lens 231, the second projection surface 232a, and the third projection surface 233a from the other end side.

[0081] The first projection lens 231 has a first projection surface 231a, and projects the light guided as a luminous flux by the first light distribution unit 221 forward from the first projection surface 231a as low beam irradiation light. The first projection lens 231 is a convex lens having the first projection surface 231a with a convex shape on its surface. The joint surface between the first projection lens 231 and the first light distribution unit 221 is not a physically joined surface, but a virtual surface.

[0082] The second projection lens 232 has a second projection surface 232a, and projects the light guided as a luminous flux by the second light distribution unit 222 forward from the second projection surface 232a as low beam irradiation light. The second projection lens 232 is a convex lens having the second projection surface 232a with a convex shape on its surface. The joint surface between the second projection lens 232 and the second light distribution unit 222 is not a physically joined surface, but a virtual surface.

[0083] The third projection lens 233 has a third projection surface 233a, and projects the light guided as a luminous flux by the third light distribution unit 223 forward from the third projection surface 233a as low beam irradiation light. The third projection lens 233 is a convex lens having the third projection surface 233a with a convex shape on its surface. The joint surface between the third projection lens 233 and the third light distribution unit 223 is not a physically joined surface, but a virtual surface.

[0084] The fourth projection lens 234 has a fourth projection surface 234a, and projects the light guided as a luminous flux by the fourth light distribution unit 224 forward from the fourth projection surface 234a as low beam irradiation light. The fourth projection lens 234 is a convex lens having the fourth projection surface 234a with a convex shape on its surface. The joint surface between the fourth projection lens 234 and the fourth light distribution unit 224 is not a physically joined surface, but a virtual surface.

[0085] The fifth projection lens 235 has a fifth projection surface 235a and projects the light guided as a light beam by the fifth light distribution unit 225 forward from the fifth projection surface 235a as low beam irradiation light. The fifth projection lens 235 is a convex lens having the fifth projection surface 235a with a convex surface on its surface. The joint surface between the fifth projection lens 235 and the fifth light distribution unit 225 is not a physically joined surface but a virtual surface. Note that each of the first projection lens 231 to the fifth projection lens 235 may be a concave lens having a concave projection surface on its surface.

[0086] Next, the path of light from the bonding surface of the incident unit 110 will be described with reference to Figures 9 and 10. Light guided from the first bonding surface 111 of the incident unit 110 to the first light guide unit 121 travels straight along the Y axis to the first emission surface 121a, as shown as light beam L1 in Figures 9 and 10. The light that reaches the reflective surface of the first concentrating optical unit 211 is totally reflected and concentrated forward in the Z axis direction by the reflective surface of the first concentrating optical unit 211, and then propagates through the first light distribution unit 221 to reach the first projection lens 231. The light that reaches the first projection lens 231 is concentrated by the first projection lens 231 and emitted forward as low beam illumination light.

[0087] 9 and 10 , the light guided from the second bonding surface 112 of the incident unit 110 to the second light guide unit 122 travels straight along the Y axis to the first reflecting surface 122b, and the light that reaches the first reflecting surface 122b is totally reflected at a right angle by the first reflecting surface 122b toward one end in the X axis direction. The light that is totally reflected at a right angle by the first reflecting surface 122b and reaches the second reflecting surface 122c is totally reflected at a right angle by the second reflecting surface 122c, and is guided along the Y axis to the second exit surface 122a, and reaches the reflecting surface of the second focusing optical unit 212.

[0088] The light that reaches the reflecting surface of the second focusing optical unit 212 is totally reflected and focused forward in the Z-axis direction by the reflecting surface of the second focusing optical unit 212, and then propagates through the second light distribution unit 222 to reach the second projection lens 232. The light that reaches the second projection lens 232 is focused by the second projection lens 232 and emitted forward as low-beam illumination light.

[0089] 9 and 10 , the light guided from the third bonding surface 113 of the incident unit 110 to the third light guide unit 123 travels straight along the Y axis to the third reflecting surface 123b, and the light that reaches the third reflecting surface 123b is totally reflected at a right angle by the third reflecting surface 123b toward one end in the X axis direction. The light that is totally reflected at a right angle by the third reflecting surface 123b and reaches the fourth reflecting surface 123c is totally reflected at a right angle by the fourth reflecting surface 123c, and is guided along the Y axis to the third exit surface 123a, and reaches the reflecting surface of the third light collecting optical unit 213.

[0090] The light that reaches the reflecting surface of the third focusing optical unit 213 is totally reflected and focused forward in the Z-axis direction by the reflecting surface of the third focusing optical unit 213, and then propagates through the third light distribution unit 223 to reach the third projection lens 233. The light that reaches the third projection lens 233 is focused by the third projection lens 233 and emitted forward as low-beam irradiation light.

[0091] 9 and 10 , the light guided from the fourth bonding surface 114 of the incident unit 110 to the fourth light guide unit 124 travels straight along the Y axis to the fifth reflecting surface 124b, and the light that reaches the fifth reflecting surface 124b is totally reflected at a right angle by the fifth reflecting surface 124b toward the other end in the X axis direction. The light that is totally reflected at a right angle by the fifth reflecting surface 124b and reaches the sixth reflecting surface 124c is totally reflected at a right angle by the sixth reflecting surface 124c, and is guided along the Y axis to the fourth exit surface 124a, and reaches the reflecting surface of the fourth light collecting optical unit 214.

[0092] The light that reaches the reflecting surface of the fourth focusing optical unit 214 is totally reflected and focused forward in the Z-axis direction by the reflecting surface of the fourth focusing optical unit 214, and then propagates through the fourth light distribution unit 224 to reach the fourth projection lens 234. The light that reaches the fourth projection lens 234 is focused by the fourth projection lens 234 and emitted forward as low-beam irradiation light.

[0093] 9 and 10 , the light guided from the fifth bonding surface 115 of the incident unit 110 to the fifth light guide unit 125 travels straight along the Y axis to the seventh reflecting surface 125b, and the light that reaches the seventh reflecting surface 125b is totally reflected at a right angle by the seventh reflecting surface 125b toward the other end in the X axis direction. The light that is totally reflected at a right angle by the seventh reflecting surface 125b and reaches the eighth reflecting surface 125c is totally reflected at a right angle by the eighth reflecting surface 125c, and is guided along the Y axis to the fifth exit surface 125a, and reaches the reflecting surface of the fifth light collecting optical unit 215.

[0094] The light that reaches the reflecting surface of the fifth concentrating optical unit 215 is totally reflected and concentrated forward in the Z-axis direction by the reflecting surface of the fifth concentrating optical unit 215, and then propagates through the fifth light distribution unit 225 to reach the fifth projection lens 235. The light that reaches the fifth projection lens 235 is concentrated by the fifth projection lens 235 and emitted forward as low-beam irradiation light.

[0095] In the light-source distribution element 100 according to the first embodiment configured as described above, the incident portion 110 has three or more bonding surfaces 111 to 115, and has exit surfaces 121 a to 125 a corresponding to the bonding surfaces 111 to 115 of the incident portion 110, and three or more light guide portions 121 to 125 are provided, each of which guides light from the corresponding bonding surface 111 to 115 to the corresponding exit surface 121 a to 125 a, and among the plurality of light guide portions 121 to 125, the pair of opposing surfaces of the light guide portions 122 and 123 whose exit surfaces 122 a and 123 a are located on one end side from the center in the X-axis direction are located on one end side. The light guides 124, 125 have a pair of reflecting surfaces 122b, 122c, 123b, 123c on the side thereof that are inclined with respect to the optical axis of the light source 1, and among the plurality of light guides 121 to 125, the pair of opposing surfaces of the light guides 124, 125 whose exit surfaces 124a, 125a are located on the other end side of the center in the X-axis direction have a pair of reflecting surfaces 124b, 124c, 125b, 125c on the other end side that are inclined with respect to the optical axis of the light source 1, and by utilizing three or more plurality of light guides 121 to 125, the incident light beam that has entered the entrance portion 110 is split into a plurality of beams in the Z-axis direction, and the split light beams are emitted from the exit surfaces 121a to 125a.

[0096] In this way, by dividing and branching the incident light beam incident from the incident section 110 into three or more beams in one direction by the three or more light guiding sections 121 to 125, it is possible to further reduce the apparent size of the light source in the division direction relative to the three or more joint surfaces 111 to 115, i.e., in one direction. Therefore, the light utilization efficiency of the light source distribution element 100 is not deteriorated, and the light source distribution element 100 can be made thinner in one direction by simplifying the structure without reducing the light utilization efficiency.

[0097] Furthermore, in the light-source distribution element 100 according to the first embodiment, the bonding surface of the incident portion 110 is divided into first bonding surface 111 to fifth bonding surface 115 at equal lengths in one direction, and first light guiding portion 121 to fifth light guiding portion 125 have first emission surface 121 a to fifth emission surface 125 a corresponding to the first bonding surface 111 to fifth bonding surface and arranged without overlapping in one direction and the other direction, and a second light guiding portion 121 is provided at one end side with a pair of reflecting surfaces inclined at 45 degrees toward one end side with respect to the corresponding bonding surface of the incident portion 110. The light source distribution element 100 has a light section 122 and a third light guiding section 123, and a fourth light guiding section 124 and a fifth light guiding section 125 at the other end thereof, each having a pair of reflective surfaces inclined at 45 degrees toward the other end thereof relative to the corresponding joint surface of the incident section 110. The third light guiding section 123 has a light guiding section that is continuous in one direction from the third joint surface 113 to the second light guiding section 122, and the fifth light guiding section 125 has a light guiding section that is continuous in one direction from the third joint surface 113 to the fourth light guiding section 124. This makes it possible to obtain a thin light source distribution element 100 with a simple structure and without reducing light utilization efficiency.

[0098] The headlight module according to the first embodiment applies the light source distribution element 100 described above, has a plurality of projection surfaces positioned along the other direction, and is equipped with a light distribution forming section 200 that reflects light from the exit surfaces 121a to 125a of the plurality of light-guiding sections 121 to 125 in the light source distribution element 100 to one end side in one direction and guides it to the plurality of projection surfaces 231a to 235a. This makes it possible to reduce the length in the direction perpendicular to the plane formed by the one direction and the other direction of the plurality of projection surfaces 231a to 235a, i.e., the height direction, and thereby simplify the structure and make it possible to make the module thinner in the height direction without reducing light utilization efficiency.

[0099] The headlamp module according to the first embodiment is resistant to variations in placement accuracy for multiple light beams and is easy to handle because the light-source distribution element 100 and the light distribution forming unit 200 are integrally formed from a transparent material. Furthermore, integral formation reduces loss due to Fresnel reflection. The headlamp module according to the first embodiment may be used as one element of a low-beam automotive headlamp device, and multiple headlamp modules according to the first embodiment may be arranged in parallel in other directions, such as the left and right directions of the vehicle.

[0100] Embodiment 2 A light-source distribution element 100 and a headlight module according to embodiment 2 will be described with reference to Figures 11 to 18. The headlight module according to embodiment 2 differs from the headlight module according to embodiment 1 in that the joining surfaces of the incident portion 110 are five first joining surfaces 111 to fifth joining surfaces 115, the collective light-guiding portion 120 are five first light-guiding portions 121 to fifth light-guiding portions 125, the collective light-collecting optical portion 210 are five first light-collecting optical portions 211 to fifth light-collecting optical portions 215, the collective light-distributing portion 200 are five first light-distributing portions 221 to fifth light-distributing portions 225, and the projection portion 230 are five first projection lenses 231 to fifth projection lenses 235. 11 to 18 in that the surfaces are three, a first bonding surface 111, a second bonding surface 112, and a fourth bonding surface 114, the collective light-guiding section 120 is three, a first light-guiding section 121, a second light-guiding section 122, and a fourth light-guiding section 124, the collective light-collecting optical section 210 is three, a first light-collecting optical section 211, a second light-collecting optical section 212, and a fourth light-collecting optical section 214, the collective light-distributing section 200 is three, a first light-distributing section 221, a second light-distributing section 222, and a fourth light-distributing section 224, and the projection section 230 is three, a first projection lens 231, a second projection lens 232, and a fourth projection lens 234. Note that in Figures 11 to 18, the same reference numerals as those in Figures 1 to 10 indicate the same or corresponding parts.

[0101] The following description will focus on the differences from the headlamp module according to embodiment 1. The joint surfaces of the incident portion 110 are divided along the Z-axis direction into portions having the same length, i.e., the same width, and include a first joint surface 111 located in the center, a second joint surface 112 located on one end side in one direction from the center, and a fourth joint surface 114 located on the other end side in one direction from the center.

[0102] The collective light-guiding section 120 has a joint surface that joins with the joint surface of the light-source distribution element 100, and has three exit surfaces, i.e., a first exit surface 121 a, a second exit surface 122 a, and a fourth exit surface 124 a, that are arranged without overlapping in the Z-axis direction and the X-axis direction, and guides light from the joint surface of the light-source distribution element 100 to the first exit surface 121 a, the second exit surface 122 a, and the fourth exit surface 124 a. The length W in the X-axis direction of each of the first exit surface 121 a, the second exit surface 122 a, and the fourth exit surface 124 a is the same as the length W in the X-axis direction of each of the first exit surface 121 a, the second exit surface 122 a, and the fourth exit surface 124 a in the first embodiment.

[0103] The collective light-guiding section 120 includes a first light-guiding section 121, a second light-guiding section 122, and a fourth light-guiding section 124. The first light-guiding section 121, the second light-guiding section 122, and the fourth light-guiding section 124 differ from the first light-guiding section 121, the second light-guiding section 122, and the fourth light-guiding section 124 in embodiment 1 only in their lengths along the Z-axis direction, but are otherwise the same.

[0104] In this way, in light-source distribution element 100 in which collective light-guiding section 120 has three exit surfaces, by dividing the luminous flux from light source 1 into three, the apparent height of the light source can be reduced, the length of the side in the Z-axis direction of the exit surface of collective light-guiding section 120 can be reduced, and the length of the side in the Z-axis direction of each of first exit surface 121 a, second exit surface 122 a, and fourth exit surface 124 a can be reduced. When light-source distribution element 100 according to embodiment 1 is applied to a headlight module, the height of the projection surface can be reduced, and miniaturization can be achieved.

[0105] The light distribution forming unit 200 guides light from the first exit surface 121a, the second exit surface 122a, and the fourth exit surface 124a of the light source distribution element 100 to the first projection surface 231a, the second projection surface 232a, and the fourth projection surface 234a, respectively, and projects the light from the first projection surface 231a, the second projection surface 232a, and the fourth projection surface 234a.

[0106] The first light collecting optical unit 211, the second light collecting optical unit 212, and the fourth light collecting optical unit 214 of the collective light collecting optical unit 210 in the light distribution forming unit 200 are the same as the first light collecting optical unit 211, the second light collecting optical unit 212, and the fourth light collecting optical unit 214, respectively, in embodiment 1. The first light distribution unit 221, the second light distribution unit 222, and the fourth light distribution unit 224 of the collective light distribution unit 220 in the light distribution forming unit 200 are the same as the first light distribution unit 221, the second light distribution unit 222, and the fourth light distribution unit 224, respectively, in embodiment 1. The first projection lens 231, the second projection lens 232, and the fourth projection lens 234 of the projection section 230 in the light distribution forming section 200 are the same as the first projection lens 231, the second projection lens 232, and the fourth projection lens 234, respectively, in embodiment 1.

[0107] Next, the path of light from the bonding surface of the incident unit 110 will be described with reference to Figures 17 and 18. Light guided from the first bonding surface 111 of the incident unit 110 to the first light guiding unit 121 travels straight along the Y axis to the first emission surface 121a, as shown as light beam L1 in Figures 17 and 18. The light that reaches the reflective surface of the first concentrating optical unit 211 is totally reflected and concentrated forward and downward in the Z axis direction by the reflective surface of the first concentrating optical unit 211, propagates through the first light distribution unit 221, and reaches the first projection lens 231. The light that reaches the first projection lens 231 is focused by the first projection lens 231 and emitted forward as low beam illumination light.

[0108] 17 and 18 , the light guided from the second bonding surface 112 of the incident unit 110 to the second light guide unit 122 travels straight along the Y axis to the first reflecting surface 122 b, and the light that reaches the first reflecting surface 122 b is totally reflected at a right angle by the first reflecting surface 122 b toward one end in the X axis direction. The light that has been totally reflected at a right angle by the first reflecting surface 122 b and reaches the second reflecting surface 122 c is totally reflected at a right angle by the second reflecting surface 122 c, and is guided along the Y axis to the second exit surface 122 a, and reaches the reflecting surface of the second focusing optical unit 212.

[0109] The light that reaches the reflective surface of the second focusing optical unit 212 is totally reflected and focused downward in the Z-axis direction by the reflective surface of the second focusing optical unit 212, and then propagates through the second light distribution unit 222 to reach the second projection lens 232. The light that reaches the second projection lens 232 is focused by the second projection lens 232 and emitted forward as low-beam illumination light.

[0110] 17 and 18 , the light guided from the fourth bonding surface 114 of the incident unit 110 to the fourth light guide unit 124 travels straight along the Y axis to the fifth reflecting surface 124b, and the light that reaches the fifth reflecting surface 124b is totally reflected at a right angle by the fifth reflecting surface 124b toward the other end in the X axis direction. The light that is totally reflected at a right angle by the fifth reflecting surface 124b and reaches the sixth reflecting surface 124c is totally reflected at a right angle by the sixth reflecting surface 124c, and is guided along the Y axis to the fourth exit surface 124a, and reaches the reflecting surface of the fourth light collecting optical unit 214.

[0111] The light that reaches the reflecting surface of the fourth focusing optical unit 214 is totally reflected and focused downward in the Z-axis direction by the reflecting surface of the fourth focusing optical unit 214, and then propagates through the fourth light distribution unit 224 to reach the fourth projection lens 234. The light that reaches the fourth projection lens 234 is focused by the fourth projection lens 234 and emitted forward as low-beam irradiation light.

[0112] The light-source distribution element 100 according to the second embodiment configured as described above splits and branches the incident light flux incident from the incident unit 110 into three in one direction by the first light guiding unit 121, the second light guiding unit 122, and the fourth light guiding unit 124, thereby making it possible to reduce the apparent size of the light source in the split direction, i.e., in one direction, relative to the three light-emitting reference surfaces, i.e., the first bonding surface 111, the second bonding surface 112, and the fourth bonding surface 114. Therefore, the light utilization efficiency is not deteriorated, and the structure can be simplified and made thin.

[0113] Furthermore, the headlight module according to the second embodiment applies the above-described light source distribution element 100, and uses the light distribution forming unit 200 to project light from the first projection lens 231, the second projection lens 232, and the fourth projection lens 234, which are positioned along the other direction. This makes it possible to reduce the length in the direction perpendicular to the plane formed by the one direction and the other direction of the first projection lens 231, the second projection lens 232, and the fourth projection lens 234, i.e., the height direction, and thereby simplify the structure and make it possible to reduce the thickness in the height direction without reducing the light utilization efficiency.

[0114] In the first embodiment, the joint surface of the incident portion 110 is divided into five, and light from the five divided joint surfaces 111 to 115 of the incident portion 110 is guided to the five exit surfaces 121 a to 125 a of the light-source distribution element 100, and the light from the five exit surfaces 121 a to 125 a of the light-source distribution element 100 is propagated to the light distribution formation portion 200 to be projected from the five projection surfaces 231 a to 235 a. In the second embodiment, the joint surface of the incident portion 110 is divided into three, and the joint surfaces 111, 112 of the incident portion 110 are guided to the five divided joint surfaces 111, 112 of the light-source distribution element 100. , 114 is guided to three exit surfaces 121a, 122a, 124a of the light source distribution element 100, and the light from the three exit surfaces 121a, 122a, 124a of the light source distribution element 100 is propagated to the light distribution forming unit 200 and projected from three projection surfaces 231a, 232a, 234a. However, the joining surface of the incident portion 110 may be divided into four or seven, and the light source distribution element 100 and the light distribution forming unit 200 may be configured to match the number of divisions of the joining surface of the incident portion 110, as in the first embodiment.

[0115] A preferred headlamp module is one in which the joint surface of incident portion 110 is divided into an odd number of portions equal to or greater than three, a first light guiding portion is disposed on the joint surface located in the center, half of the remaining light guiding portions are disposed in the Z-axis direction on either side of the first light guiding portion, and half of the light guiding portions disposed on one end side of the Z-axis direction are inclined toward one end side of the X-axis direction, and half of the light guiding portions disposed on the other end side of the Z-axis direction are inclined toward the other end side of the X-axis direction. In this case, the light flux from lens 116 can be concentrated at the joint surface located in the center of incident portion 110, making it easier to form a light distribution from the projection surface.

[0116] Embodiment 3 A light-source distribution element 100 and a headlight module according to embodiment 3 will be described with reference to Fig. 19 to Fig. 26. In the headlight module according to embodiment 1, the lengths in the X-axis direction of the first to fifth emission surfaces 121a to 125a are all W, whereas the length in the X-axis direction of the first emission surface 121a is W, and the lengths in the X-axis direction of the second emission surface 122a and the fourth emission surface 124a are W, which are shorter than W. １ , the length of the third light exit surface 123a and the fifth light exit surface 125a in the X-axis direction is W １ Shorter W ２ The difference is that

[0117] Due to this difference, the distance between the pair of reflecting surfaces in the second light guiding unit 122 and the fourth light guiding unit 124, the length in the X-axis direction of the second light collecting optical unit 212 and the fourth light collecting optical unit 214, the length in the X-axis direction of the second light distribution unit 222 and the fourth light distribution unit 224, and the length in the X-axis direction of the second projection lens 232 and the fourth projection lens 234 are W １ , the distance between the pair of reflecting surfaces in the third light guiding unit 123 and the fifth light guiding unit 125, the lengths in the X-axis direction of the third light collecting optical unit 213 and the fifth light collecting optical unit 215, the lengths in the X-axis direction of the third light distribution unit 223 and the fifth light distribution unit 225, and the lengths in the X-axis direction of the third projection lens 233 and the fifth projection lens 235 are W ２ The difference is in the other points. １ , W ２ The relationship is W>W １ >W ２ is.

[0118] However, the lengths in the X-axis direction of the second emission surface 122a, the second light guiding unit 122, the second collecting optical unit 212, the second light distribution unit 222, and the second projection lens 232 may be different from the lengths in the X-axis direction of the fourth emission surface 124a, the fourth light guiding unit 124, the fourth collecting optical unit 214, the fourth light distribution unit 224, and the fourth projection lens 234. Similarly, the lengths in the X-axis direction of the third emission surface 123a, the third light guiding unit 123, the third collecting optical unit 213, the third light distribution unit 223, and the third projection lens 233 may be different from the lengths in the X-axis direction of the fifth emission surface 125a, the fifth light guiding unit 125, the fifth collecting optical unit 215, the fifth light distribution unit 225, and the fifth projection lens 235. 19 to 26, the same reference numerals as those in FIGS. 1 to 10 indicate the same or corresponding parts.

[0119] The following description will focus on differences from the headlamp module according to embodiment 1. The first light guiding section 121 is the same as the first light guiding section 121 in embodiment 1. The opposing surface on one end side in the X-axis direction of the pair of opposing surfaces in the second light guiding section 122 has a second rising surface 122d that is perpendicular to the second joining surface 112 from the bottom surface that contacts the second joining surface 112 of the incident section 110, and a second reflecting surface 122c that is inclined 45 degrees toward one end side with respect to the second joining surface 112 from the upper side of the second rising surface 122d to the second emission surface 122a. The distance along the X-axis between the first reflecting surface 122b and the second reflecting surface 122c is W １ and the distance W between the second light exit surfaces 122a along the X-axis direction １ is the same as

[0120] The length from the bottom to the top of the second rising surface 122d is the length W of the second light exit surface 122a in the X-axis direction. １ Offset amount (W-W １ The amount of light totally reflected by second reflecting surface 122c after being totally reflected by first reflecting surface 122b is comparable to that in the case where second rising surface 122d is not provided, because there is no light from second bonding surface 112 of incident section 110 at both ends of the bonding surface of second light guiding section 122 that contacts second bonding surface 112 of incident section 110.

[0121] The opposing surface on one end side in the X-axis direction of the pair of opposing surfaces in the third light guiding unit 123 has a fourth rising surface 123d that is perpendicular to the third bonding surface 113 from the bottom surface that contacts the third bonding surface 113 of the incident unit 110, and a fourth reflecting surface 123c that is inclined 45 degrees toward one end side with respect to the third bonding surface 113 from the upper side of the fourth rising surface 123d to the third emission surface 123a. The distance along the X-axis direction between the third reflecting surface 123b and the fourth reflecting surface 123c is (W １ +W ２ )

[0122] The distance W between the third light exit surfaces 123a along the X-axis direction ２ is the distance (W １ +W ２ ) to the distance W between the first reflecting surface 122b and the second reflecting surface 122c in the second light guiding section 122 along the X-axis direction. １ The distance (W １ +W ２ ) is the distance W between the first reflecting surface 122b and the second reflecting surface 122c of the second light guiding section 122 along the X-axis direction. １ Twice as much as 2W １ Shorter.

[0123] The length from the bottom to the top of the fourth rising surface 123d is the offset (W-W2) relative to the length W2 of the third exit surface 123a in the X-axis direction, in other words, (2W-(W １ The amount of light totally reflected by fourth reflecting surface 123c after being totally reflected by third reflecting surface 123b is comparable to that in the case where fourth rising surface 123d is not provided, because there is no light from third bonding surface 113 of incident unit 110 at both ends of the bonding surface of third light guiding unit 123 that contacts third bonding surface 113 of incident unit 110.

[0124] The opposing surface on the other end side in the X-axis direction of the pair of opposing surfaces in the fourth light guiding unit 124 has a sixth rising surface 124d that is perpendicular to the fourth bonding surface 114 from the bottom surface that contacts the fourth bonding surface 114 of the incident unit 110, and a sixth reflecting surface 124c that is inclined 45 degrees toward the other end side with respect to the fourth bonding surface 114 from the upper side of the sixth rising surface 124d to the fourth emission surface 124a. The distance along the X-axis direction between the fifth reflecting surface 124b and the sixth reflecting surface 124c is W １ and the distance W between the fourth light exit surfaces 124a along the X-axis direction １ is the same as

[0125] The length from the bottom to the top of the sixth rising surface 124d is the length W of the fourth light exit surface 124a in the X-axis direction. １ Offset amount (W-W １ The amount of light totally reflected by sixth reflecting surface 124c after being totally reflected by fifth reflecting surface 124b is comparable to that in the case where sixth rising surface 124d is not provided, because there is no light from fourth bonding surface 114 of incident section 110 at both ends of the bonding surface of fourth light guiding section 124 that contacts fourth bonding surface 114 of incident section 110.

[0126] The opposing surface on the other end side in the X-axis direction of the pair of opposing surfaces in the fifth light guiding unit 125 has an eighth rising surface 125d that is perpendicular to the fifth bonding surface 115 from the bottom surface that contacts the fifth bonding surface 115 of the incident unit 110, and an eighth reflecting surface 125c that is inclined 45 degrees toward the other end side with respect to the fifth bonding surface 115 from the upper side of the eighth rising surface 125d to the fifth emission surface 125a. The distance along the X-axis direction between the seventh reflecting surface 125b and the eighth reflecting surface 125c is (W １ +W ２ )

[0127] The distance W between the fifth light exit surfaces 125a along the X-axis direction ２ is the distance (W) between the seventh reflecting surface 125b and the eighth reflecting surface 125c along the X-axis direction. １ +W ２ ) to the distance W between the fifth reflecting surface 124b and the sixth reflecting surface 124c in the fourth light guiding section 124 along the X-axis direction. １The distance (W ) between the seventh reflecting surface 125 b and the eighth reflecting surface 125 c of the fifth light guiding unit 125 along the X-axis direction is １ +W ２ ) is the distance W between the fifth reflecting surface 124b and the sixth reflecting surface 124c of the fourth light guiding section 124 along the X-axis direction. １ Twice as much as 2W １ Shorter.

[0128] The length from the bottom to the top of the eighth rising surface 125d is the offset (W-W2) relative to the length W2 of the fifth exit surface 125a in the X-axis direction, in other words, (2W-(W １ The amount of light totally reflected by eighth reflecting surface 125c after being totally reflected by seventh reflecting surface 125b is comparable to that in the case where eighth rising surface 125d is not provided, because there is no light from fifth bonding surface 115 of incident unit 110 at both ends of the bonding surface of fifth light guiding unit 125 that contacts fifth bonding surface 115 of incident unit 110.

[0129] The sum of the lengths in the X-axis direction from the first light exit surface 121a to the fifth light exit surface 125a (W+2(W １ +W2)) is 5W-((W+2(W) where the total length of all W is 5W １ +W2))), that is, 4W-2(W １ +W2) becomes shorter.

[0130] The light distribution forming unit 200 is the same as the light distribution forming unit 200 in the first embodiment except for its length in the X-axis direction. The first light collecting optical unit 211 is the same as the first light collecting optical unit 211 in the first embodiment. The lengths in the X-axis direction of the second light collecting optical unit 212 and the fourth light collecting optical unit 214 are W １ and the distance W between the second light exit surface 122a and the fourth light exit surface 124a along the X-axis direction is １ is the same as

[0131] The lengths of the second light distribution section 222 and the fourth light distribution section 224 in the X-axis direction are W １ and the distance W between the second light exit surface 122a and the fourth light exit surface 124a along the X-axis direction is １The lengths of the second projection lens 232 and the fourth projection lens 234 in the X-axis direction are respectively W １ and the distance W between the second light exit surface 122a and the fourth light exit surface 124a along the X-axis direction is １ is the same as

[0132] The lengths of the third and fifth focusing optical units 213 and 215 in the X-axis direction are W ２ and the distance W between the third and fifth light exit surfaces 123a and 125a along the X-axis direction is ２ The lengths of the third light distribution section 223 and the fifth light distribution section 225 in the X-axis direction are respectively W ２ and the distance W between the third and fifth light exit surfaces 123a and 125a along the X-axis direction is ２ is the same as

[0133] The lengths of the third projection lens 233 and the fifth projection lens 235 in the X-axis direction are W ２ and the distance W between the third and fifth light exit surfaces 123a and 125a along the X-axis direction is ２ The sum of the lengths in the X-axis direction of the first projection surface 231a to the fifth projection surface 235a arranged in a row along the X-axis (W+2(W １ +W2)) is 4W-2 (W for the total of 5W of all lengths １ +W2) becomes shorter.

[0134] As described above, the light source distribution element 100 according to embodiment 3 has the same effects as the light source distribution element 100 according to embodiment 1, and in addition, it can shorten the length in the X-axis direction, simplify the structure, and shorten the width direction and make it thinner without reducing light utilization efficiency. Furthermore, by including the light source distribution element 100 and the light distribution forming unit 200 described above, the headlamp module according to embodiment 3 can shorten the width direction and make it thinner in the height direction without reducing light utilization efficiency with a simple structure.

[0135] Embodiment 4 A headlight module according to embodiment 4 will be described with reference to Figures 27 to 32. The headlight module according to embodiment 4 differs from the headlight module according to embodiment 3 in that a cutoff line forming surface 220a is provided in the collected light distribution section 220 in the light distribution forming section 200. Note that in Figures 27 to 32, the same reference numerals as those in Figures 1 to 10 and Figures 19 to 26 indicate the same or corresponding parts.

[0136] The following mainly describes the differences from the headlight module according to embodiment 3. Since the headlight module according to embodiment 3 is basically the same as the headlight module according to embodiment 3 except for the collective light distribution section 220 in the light distribution forming section 200, the description will mainly focus on the collective light distribution section 220. The collective light distribution section 220 has a cutoff line forming surface 220a on its bottom surface, that is, the surface located on the side of the incident section 110 in the Y-axis direction, which has a ridge line for forming a cutoff line along the X-axis direction, and the area from the ridge line of the cutoff line forming surface 220a to the front surface of the collective light-collecting optical section 210 is a first region 220A, and the area from the ridge line of the cutoff line forming surface 220a to the projection section 230 is a second region 220B.

[0137] In the first region 220A, the bottom surface is a horizontal plane along the Z-X plane, and the top surface opposite the bottom surface is also a horizontal plane along the Z-X plane. In order to form a cutoff line, the bottom surface may be a surface that is inclined toward the Z-axis direction relative to the Z-X plane, and the top surface may also be a surface that is inclined toward the Z-axis direction relative to the Z-X plane. Furthermore, at least one of the bottom surface and the top surface may be changed to a surface that is parallel to the Z-X plane. The bottom surface of the first region 220A has a reflective surface.

[0138] In the collective light distribution unit 220, light from the front surface of the collective light collecting optical unit 210 is totally reflected by the cutoff line forming surface 220a, which is a reflective surface in the first region 220A, and the light on which a cutoff line is formed is propagated to the projection unit 230 via the second region 220B. The bottom and top surfaces of the second region 220B are also horizontal surfaces along the Z-X plane, like the bottom and top surfaces of the first region 220A, but may be surfaces that are inclined toward the Z-axis direction with respect to the Z-X plane, or surfaces that are parallel to the Z-X plane.

[0139] The first light distribution section 221 constituting the collective light distribution section 220 has a first cutoff line forming surface 221a having a ridge line for forming a cutoff line along the X-axis direction. The first region 221A is the region from the ridge line of the first cutoff line forming surface 221a to the front surface of the first light collecting optical section 211, and the second region 221B is the region from the ridge line of the first cutoff line forming surface 221a to the first projection lens 231.

[0140] In the first region 221A, the bottom surface is a surface located on the side of the incident portion 110 and is a horizontal plane along the Z-X plane. The top surface is also a horizontal plane along the Z-X plane. The bottom surface of the first region 221A has a first cutoff line forming surface 221a, which is a reflective surface. The length in the X-axis direction of a pair of opposing surfaces that face each other parallel to the X-axis direction, i.e., the distance between them, is W. A portion of the light beam L1 from the front surface of the first focusing optical unit 211 is reflected by the first cutoff line forming surface 221a. The light that is reflected by the first cutoff line forming surface 221a and on which a cutoff line is formed is guided to the first projection lens 231 via the second region 221B.

[0141] Furthermore, the remaining light of the light beam L1 from the front surface of the first converging optical unit 211 is not reflected by the first cutoff line forming surface 221a, but is guided directly to the first projection lens 231 via the second area 221B. The light reflected by the first cutoff line forming surface 221a and the light not reflected by the first cutoff line forming surface 221a are combined to form a cutoff light distribution, which is projected from the first projection lens 231 as a low beam.

[0142] The second light distribution section 222 constituting the collective light distribution section 220 has a second cutoff line forming surface 222a having a ridge line for forming a cutoff line along the X-axis direction. The first region 222A is the region from the ridge line of the second cutoff line forming surface 222a to the front surface of the second concentrating optical section 212, and the second region 222B is the region from the ridge line of the second cutoff line forming surface 222a to the second projection lens 232.

[0143] In the first region 222A, the bottom surface is a surface located on the side of the incident section 110 and is a horizontal plane along the Z-X plane. The top surface is also a horizontal plane along the Z-X plane. The bottom surface of the first region 222A has a second cutoff line forming surface 222a, which is a reflective surface. The length in the X-axis direction of a pair of opposing surfaces that face each other parallel to the X-axis direction, i.e., the distance between them, is W. A portion of the light beam L2 from the front surface of the second focusing optical section 212 is reflected by the second cutoff line forming surface 222a. The light reflected by the second cutoff line forming surface 222a and on which a cutoff line has been formed is guided to the second projection lens 232 via the second region 222B.

[0144] Furthermore, the remaining light of the light beam L2 from the front surface of the second converging optical unit 212 is not reflected by the second cutoff line forming surface 222a, but is guided directly to the second projection lens 232 via the second area 222B. The light reflected by the second cutoff line forming surface 222a and the light not reflected by the first cutoff line forming surface 222a are combined to form a cutoff light distribution, which is projected as a low beam from the second projection lens 232.

[0145] The third light distribution section 223 constituting the collective light distribution section 220 has a third cutoff line forming surface 223a having a ridge line for forming a cutoff line along the X-axis direction. The first region 223A is the region from the ridge line of the third cutoff line forming surface 223a to the front surface of the third concentrating optical section 213, and the second region 223B is the region from the ridge line of the third cutoff line forming surface 223a to the third projection lens 233.

[0146] In the first region 223A, the bottom surface is a surface located on the side of the incident section 110 and is a horizontal plane along the Z-X plane. The top surface is also a horizontal plane along the Z-X plane. The bottom surface of the first region 223A has a third cutoff line forming surface 223a, which is a reflective surface. The length in the X-axis direction of a pair of opposing surfaces that face each other parallel to the X-axis direction, i.e., the distance between them, is W. A portion of the light beam L3 from the front surface of the third focusing optical section 213 is reflected by the third cutoff line forming surface 223a. The light that is reflected by the first cutoff line forming surface 223a and on which a cutoff line is formed is guided to the third projection lens 233 via the second region 223B.

[0147] Furthermore, the remaining light of the light beam L3 from the front surface of the third converging optical unit 213 is not reflected by the third cutoff line forming surface 223 a, but is guided directly to the second projection lens 232 via the second area 223B. The light reflected by the third cutoff line forming surface 223 a and the light not reflected by the third cutoff line forming surface 223 a are combined to form a cutoff light distribution, which is projected as a low beam from the second projection lens 232.

[0148] The fourth light distribution section 224 constituting the collective light distribution section 220 has a fourth cutoff line forming surface 224a having a ridge line for forming a cutoff line along the X-axis direction. The first region 224A is the region from the ridge line of the fourth cutoff line forming surface 224a to the front surface of the fourth light collecting optical section 214, and the second region 224B is the region from the ridge line of the fourth cutoff line forming surface 224a to the fourth projection lens 234.

[0149] In the first region 224A, the bottom surface is a surface located on the side of the incident section 110 and is a horizontal plane along the Z-X plane. The top surface is also a horizontal plane along the Z-X plane. The bottom surface of the first region 224A has a fourth cutoff line forming surface 224a, which is a reflective surface. The length in the X-axis direction of a pair of opposing surfaces that face each other parallel to the X-axis direction, i.e., the distance between them, is W. A portion of the light beam L4 from the front surface of the fourth focusing optical section 214 is reflected by the fourth cutoff line forming surface 224a. The light reflected by the fourth cutoff line forming surface 224a and on which a cutoff line has been formed is guided to the fourth projection lens 234 via the second region 224B.

[0150] Furthermore, the remaining light of the light beam L4 from the front surface of the fourth converging optical unit 214 is not reflected by the fourth cutoff line forming surface 224a, but is guided directly to the fourth projection lens 234 via the second area 224B. The light reflected by the fourth cutoff line forming surface 224a and the light not reflected by the fourth cutoff line forming surface 224a are combined to form a cutoff light distribution, which is projected from the fourth projection lens 234 as a low beam.

[0151] The fifth light distribution section 225 constituting the collective light distribution section 220 has a fifth cutoff line forming surface 225a having a ridge line for forming a cutoff line along the X-axis direction. The first region 225A is the region from the ridge line of the fifth cutoff line forming surface 225a to the front surface of the fifth concentrating optical section 215, and the second region 225B is the region from the ridge line of the fifth cutoff line forming surface 225a to the fifth projection lens 235.

[0152] In the first region 225A, the bottom surface is a surface located on the side of the incident portion 110 and is a horizontal plane along the Z-X plane. The top surface is also a horizontal plane along the Z-X plane. The bottom surface of the first region 225A has a fifth cutoff line forming surface 225a, which is a reflective surface. The length in the X-axis direction of a pair of opposing surfaces that face each other parallel to the X-axis direction, i.e., the distance between them, is W. A portion of the light beam L5 from the front surface of the fifth focusing optical unit 215 is reflected by the fifth cutoff line forming surface 225a. The light reflected by the fifth cutoff line forming surface 225a and on which a cutoff line is formed is guided to the fifth projection lens 235 via the second region 225B.

[0153] Furthermore, the remaining light of the light beam L5 from the front surface of the fifth converging optical unit 215 is not reflected by the fifth cutoff line forming surface 225a, but is guided directly to the fifth projection lens 235 via the second area 225B. The light reflected by the fifth cutoff line forming surface 225a and the light not reflected by the fifth cutoff line forming surface 225a are combined to form a cutoff light distribution, which is projected as a low beam from the fifth projection lens 235.

[0154] The ridge lines for forming the cutoff lines of each of the first cutoff line forming surface 221 a to the fifth cutoff line forming surface 225 a are underlines on the joint surfaces of the first region portions 221 A to 225 A and the second region portions 221 B to 225 B, that is, the front edge of the reflecting surface on the bottom surface of each of the first region portions 221 A to 225 A. The ridge lines for forming the cutoff lines are positioned so that the upper side, that is, the outside of the light distribution pattern, is dark and the lower side, that is, the inside of the light distribution pattern, is bright.

[0155] The headlight module according to the fourth embodiment configured in this manner not only achieves the same effects as the headlight module according to the third embodiment, but also, because the collective light distribution unit 220 has the cutoff line forming surface 220a for forming a cutoff line, the light projected from the projection unit 230 can be projected forward as low-beam irradiation light, which is light of a light distribution pattern having a cutoff line. Furthermore, by changing the shape of the ridge line for forming the cutoff line of each of the cutoff line forming surfaces 221a to 225a of the first light distribution unit 221 to the fifth light distribution unit 225, it is possible to obtain a light distribution pattern having a desired cutoff line shape.

[0156] In the headlight module according to the fourth embodiment, the cutoff line forming surfaces 221a to 225a, the first regions 221A to 225A, and the second regions 221B to 225B are each unique in the first light distribution section 221 to the fifth light distribution section 225, but the cutoff line forming surfaces may be continuous in the X-axis direction. That is, the cutoff line forming surfaces 221a to 225a are all rectangular with no steps located on the same plane.

[0157] The first light distribution section 221 to the fifth light distribution section 225 in the first and second embodiments may be replaced with the first light distribution section 221A to the fifth light distribution section 225A having the cutoff line forming surfaces 221a to 225a, respectively, of the fourth embodiment. This makes it possible to obtain a light distribution pattern having a desired cutoff line shape.

[0158] Furthermore, the embodiments may be freely combined, or any of the components in each embodiment may be modified, or any of the components in each embodiment may be omitted.

[0159] The light source distribution element for a headlamp device and the headlamp module according to the present disclosure are suitable for use in headlamp devices for automobiles and motorcycles, particularly in low-beam headlights.

[0160] 1 Light source, 100 Light source distribution element for headlamp device, 110 Incident portion, 111 First bonding surface, 112 Second bonding surface, 113 Third bonding surface, 114 Fourth bonding surface, 115 Fifth bonding surface, 120 Collective light guiding portion, 121 First light guiding portion, 122 Second light guiding portion, 123 Third light guiding portion, 124 Fourth light guiding portion, 125 Fifth light guiding portion, 121a First exit surface, 122a Second exit surface, 123a Third exit surface, 124a Fourth exit surface, 125a Fifth exit surface, 122b First reflecting surface, 122c Second reflecting surface, 123b Third reflecting surface, 123c Fourth reflecting surface, 124b Fifth reflecting surface, 124c Sixth reflecting surface, 125b Seventh reflecting surface, 125c Eighth reflecting surface, 200 Light distribution forming portion, 210 Collecting and concentrating optical portion, 211 First concentrating optical portion, 212 Second concentrating optical portion, 213 Third concentrating optical portion, 214 Fourth concentrating optical portion, 215 Fifth concentrating optical portion, 220 Collecting and distributing portion, 220A First region, 220B Second region, 220a Cutoff line forming surface, 221 First light distribution portion, 221a First cutoff line forming surface, 222 Second light distribution portion, 222a Second cutoff line forming surface, 223 Third light distribution portion, 223a Third cutoff line forming surface, 224 Fourth light distribution portion, 224a Fourth cutoff line forming surface, 225 Fifth light distribution portion, 225a Fifth cutoff line forming surface, 230 projection unit, 231 first projection lens, 232 second projection lens, 233 third projection lens, 234 fourth projection lens, 235 fifth projection lens, 231a first projection surface, 232a second projection surface, 233a third projection surface, 234a fourth projection surface, 235a fifth projection surface, L1 to L5 first light beam to fifth light beam.

Claims

1. an incidence section to which light from a light source is incident and which has three or more bonding surfaces located along one direction in a plane perpendicular to an optical axis of the light source; a light guide portion including three or more light guide sections each having a pair of opposing surfaces facing one direction in a plane perpendicular to the optical axis of the light source and another direction perpendicular to the optical axis of the light source, each having a rectangular cross section parallel to the plane perpendicular to the optical axis of the light source, each having an exit surface corresponding to each of the plurality of bonding surfaces of the incident portion, and each guiding light from the corresponding bonding surface to the corresponding exit surface; Among the plurality of light guiding sections, the pair of opposing surfaces of the light guiding section whose exit surface is located at one end side in the other direction with respect to the light source each have a reflection surface at one end side that is inclined with respect to the optical axis of the light source, Among the plurality of light guiding sections, each of the pair of opposing surfaces of a light guiding section whose exit surface is located on the other end side in the other direction relative to the light source has a reflection surface on the other end side that is inclined with respect to the optical axis of the light source. A light source distribution element for a headlamp device.

2. 2. The light source distribution element for a headlamp device according to claim 1, wherein the reflecting surface inclined with respect to the optical axis of the light source is inclined at 45 degrees with respect to the optical axis of the light source.

3. 2. The light source distribution element for a headlamp device according to claim 1, wherein the entrance portion and the plurality of light guiding portions are integrally formed from a transparent material.

4. the plurality of bonding surfaces of the incident portion are divided in the one direction, and are five bonding surfaces including a first bonding surface located in a central portion, a second bonding surface and a third bonding surface located in this order from the central portion to one end side in the one direction, and a fourth bonding surface and a fifth bonding surface located in this order from the central portion to the other end side in the one direction, the plurality of light guiding sections are five light guiding sections including a first light guiding section to a fifth light guiding section each having a first light emitting surface to a fifth light emitting surface, a pair of opposing surfaces of the first light guiding portion are parallel to an optical axis of the light source, and the first light guiding portion guides light from a first joint surface of the incident portion to the first exit surface; a first reflecting surface and a second reflecting surface which are a pair of reflecting surfaces of the second light guiding section are inclined toward one end side in the other direction with respect to an optical axis of the light source, the first reflecting surface is located on the optical axis side of the light source, and the second reflecting surface is located on the one end side in the other direction, and the second light guiding section reflects light from a second joint surface of the incident section to the second reflecting surface by the first reflecting surface, and the second reflecting surface reflects light to the second exit surface, a third reflecting surface and a fourth reflecting surface which are a pair of reflecting surfaces of the third light guiding section are inclined toward one end side in the other direction with respect to the optical axis of the light source, the third reflecting surface of the third light guiding section is continuous with the first reflecting surface at one end side in the one direction, the third light guiding section is integrally formed with the second light guiding section from the third reflecting surface to the position of the second reflecting surface of the second light guiding section, the fourth reflecting surface of the third light guiding section is at a position away from the position of the second reflecting surface of the second light guiding section at the one end side in the other direction by a length of the third exit surface in the other direction, and the third reflecting surface of the third light guiding section reflects light from a third joint surface of the incident section to the fourth reflecting surface, and the fourth reflecting surface reflects light to the third exit surface, a fifth reflecting surface and a sixth reflecting surface which are a pair of reflecting surfaces of the fourth light guiding section are inclined toward the other end side in the other direction with respect to the optical axis of the light source, the fifth reflecting surface is located on the optical axis side of the light source, and the sixth reflecting surface is located on the other end side in the other direction, and the fourth light guiding section reflects light from a fourth joint surface of the incident section to the sixth reflecting surface, and the sixth reflecting surface reflects light to the fourth exit surface, The seventh reflecting surface and the eighth reflecting surface, which are a pair of reflecting surfaces of the fifth light guiding section, are inclined toward the other end side in the other direction with respect to the optical axis of the light source, the seventh reflecting surface of the fifth light guiding section is continuous with the fifth reflecting surface on the other end side in the one direction, the fifth light guiding section is integrally formed with the fourth light guiding section from the seventh reflecting surface to the position of the sixth reflecting surface of the fourth light guiding section, the eighth reflecting surface of the fifth light guiding section is located at a position away from the sixth reflecting surface of the fourth light guiding section on the other end side in the other direction by a length of the fifth exit surface in the other direction, and the seventh reflecting surface of the fifth light guiding section reflects light from a fifth joint surface of the entrance section to the eighth reflecting surface, and the eighth reflecting surface reflects light to the fifth exit surface. The light source distribution element for a headlamp device according to any one of claims 1 to 3.

5. a distance between the pair of reflecting surfaces of the third light guiding section in the other direction is shorter than twice the distance between the pair of reflecting surfaces of the second light guiding section in the other direction; a length in the other direction of a third exit surface of the third light guiding portion is shorter than a length in the other direction of a second exit surface of the second light guiding portion; a distance between the pair of reflecting surfaces of the fifth light guiding unit in the other direction is shorter than twice the distance between the pair of reflecting surfaces of the fourth light guiding unit in the other direction; a length in the other direction of a fifth exit surface of the fifth light guiding portion is shorter than a length in the other direction of a fourth exit surface of the fourth light guiding portion; The light source distribution element for a headlamp device according to claim 4.

6. The light-source distribution element for a headlamp device according to claim 4 , wherein the incident portion condenses incident light and guides parallel light from the first joint surface to the fifth joint surface.

7. A headlamp device comprising the light source distribution element for a headlamp device according to claim 4 and a light distribution forming unit, The light distribution forming unit is a first light collecting optical unit that reflects and collects light from a first exit surface of the first light guiding unit toward one end side in the one direction; a second light collecting optical unit that reflects and collects light from the second exit surface of the second light guiding unit toward one end side in the one direction; a third light collecting optical unit that reflects and collects light from a third exit surface of the third light guiding unit toward one end side in the one direction; a fourth light collecting optical unit that reflects and collects light from a fourth exit surface of the fourth light guiding unit toward one end side in the one direction; a fifth light collecting optical unit that reflects and collects light from a fifth exit surface of the fifth light guiding unit toward one end side in the one direction; a first light distribution unit that guides the light flux reflected and collected by the first light collecting optical unit; a second light distribution unit that guides the light flux reflected and collected by the second light collecting optical unit; a third light distribution unit that guides the light flux reflected and collected by the third light collecting optical unit; a fourth light distribution unit that guides the light flux reflected and collected by the fourth light collecting optical unit; a fifth light distribution unit that guides the light flux reflected and collected by the fifth light collecting optical unit; a first projection lens having a first projection surface and projecting the light guided as a luminous flux by the first light distribution unit from the first projection surface; a second projection lens having a second projection surface and projecting the light guided as a light beam by the second light distribution unit from the second projection surface; a third projection lens having a third projection surface and projecting the light guided as a light beam by the third light distribution unit from the third projection surface; a fourth projection lens having a fourth projection surface and projecting the light guided as a light beam by the fourth light distribution unit from the fourth projection surface; a fifth projection lens having a fifth projection surface and projecting the light guided as a light beam by the fifth light distribution section from the fifth projection surface; A headlight module in which the first projection surface to the fifth projection surface are arranged in the other direction from one end side to the other end side in the order of the third projection surface, the second projection surface, the first projection surface, the fourth projection surface, and the fifth projection surface without overlapping.

8. The first light distribution unit has a first cutoff line forming surface having a ridge for forming a cutoff line along the other direction, and projects a cutoff light distribution formed by reflecting a portion of the light from the first focusing optical unit onto the first cutoff line forming surface and directing the remaining light from the first focusing optical unit directly to the first projection lens; the second light distribution unit has a second cutoff line forming surface having a ridge line for forming a cutoff line along the other direction, and projects a cutoff light distribution formed by reflecting a part of the light from the second converging optical unit onto the second cutoff line forming surface and guiding the part of the light from the second converging optical unit directly to the second projection lens, the third light distribution unit has a third cutoff line forming surface having a ridge line for forming a cutoff line along the other direction, and projects a cutoff light distribution formed by reflecting a part of the light from the third converging optical unit onto the third cutoff line forming surface and guiding the part of the light from the third converging optical unit directly to the third projection lens, the fourth light distribution unit has a fourth cutoff line forming surface having a ridge line for forming a cutoff line along the other direction, and projects a cutoff light distribution formed by reflecting a part of the light from the fourth converging optical unit onto the fourth cutoff line forming surface and guiding the part of the light from the fourth converging optical unit to the fourth projection lens, and guiding the other light from the fourth converging optical unit directly to the fourth projection lens; the fifth light distribution unit has a fifth cutoff line forming surface having a ridge line for forming a cutoff line along the other direction, and projects a cutoff light distribution formed by reflecting a part of the light from the fifth converging optical unit onto the fifth cutoff line forming surface and guiding the part of the light from the fifth converging optical unit to the fifth projection lens, and guiding the other light from the fifth converging optical unit directly to the fifth projection lens.

8. A headlamp module according to claim 7.

9. The headlamp module according to claim 7 , wherein the headlamp device light source distribution element and the light distribution forming portion are integrally formed from a transparent material.

10. A light source distribution element for a headlamp device according to claim 1; a light distribution forming unit having a plurality of projection surfaces located along the other direction, the light distribution forming unit reflecting light from the exit surfaces of the plurality of light guiding units in the headlamp device light source distribution element toward one end side in the one direction and guiding the light to the plurality of projection surfaces; A headlamp module comprising:

11. The light distribution forming section, a collective light-collecting optical unit that reflects and collects light from the exit surfaces of the plurality of light-guiding units toward one end side in the one direction; a collective light distribution unit that guides the plurality of light beams reflected and concentrated by the collective light concentration optical unit to the plurality of projection surfaces; a projection unit having the plurality of projection surfaces and projecting the light guided as a plurality of luminous fluxes by the collective light distribution unit from each of the plurality of projection surfaces; The headlamp module of claim 10 .

12. A headlight module as described in claim 11, wherein the projection unit comprises a plurality of projection lenses each having a respective one of the plurality of projection surfaces.

13. A headlight module as described in claim 10, wherein the light source distribution element for the headlight device and the light distribution forming portion are integrally formed from a transparent material.

14. A headlight module as described in claim 11 or claim 12, wherein the collective light distribution unit has a cutoff line forming surface having a ridge for forming a cutoff line along another direction, a first region is from the ridge of the cutoff line forming surface to the collective focusing optical unit, and a second region is from the ridge of the cutoff line forming surface to the projection unit, and each of a plurality of light beams from the collective focusing optical unit is reflected by the cutoff line forming surface, and the light beams on which a cutoff line has been formed are guided to the projection unit via the second region.

15. A headlight module as described in claim 14, wherein the cutoff line forming surface has a cutoff line forming surface each having its own unique characteristic corresponding to each of the multiple light beams from the collective focusing optical unit.

16. A headlight module as described in Claim 14, wherein the cutoff line forming surface is a cutoff line forming surface located on the same plane that is continuous in the other direction with respect to multiple light beams from the collective focusing optical unit.

17. A headlight module as described in claim 14, wherein the light source distribution element for the headlight device and the light distribution forming portion are integrally formed from a transparent material.