Headlight assembly that emits first light in one emission direction and includes a light receiver for second light arriving in the opposite direction of emission.

Abstract

Headlight assembly (100, 100a, 100b, 100c, 100d), comprising: a first optical system (101, 101a, 101b, 101d) that emits first light (L1) in a predetermined emission direction; and a second optical system (102, 102a, 102c, 102d) comprising a light receiver (20) and a beam splitter (30), wherein second light (L2) which propagates in an incident direction opposite to the emission direction is incident on the beam splitter (30), wherein a part of an optical axis (C1) of the first optical system (101, 101a, 101b, 101d) coincides with a part of an optical axis of the second optical system (102, 102a, 102c, 102d) in the emission direction, and wherein the beam splitter (30) has a central part (32a) which adjusts the diameter of the second light (L2) propagating through the second optical system (102, 102a, 102c, 102d) towards the light receiver (20) to be smaller than the diameter of the second light (L2) at the entrance to the second optical system (102, 102a, 102c, 102d); wherein the beam splitter (30) emits the first light (L1) in the emission direction and the second light (L2), which propagates in the incidence direction, leads to the light receiver (20), and wherein the central part (32a) is arranged on the optical axis (C1) of the first optical system (101, 101a, 101b, 101d), wherein the central part (32a) reflects a part of the second light (L2) propagating in the direction of incidence, and wherein the central part (32a) directs this part of the second light (L2) to the light receiver (20); wherein the beam splitter (30) further comprises a peripheral part (32b) which is arranged on an outer side relative to the central part (32a), transmits the first light (L1) and reflects the second light (L2), and where the reflectivity of the peripheral part (32b) is lower than the reflectivity of the central part (32a).

Description

AREA OF TECHNOLOGY

[0001] The present disclosure relates to a headlight device which emits first light in one emission direction and includes a light receiver for second light entering in the opposite direction of emission. BACKGROUND ON THE STATE OF THE TECHNOLOGY

[0002] A highly functional headlight assembly has been proposed, comprising an optical projection system that emits illumination light and an optical imaging system with a light receiver onto which incident light is directed to detect a target object, such as another vehicle, located in the direction of emission of the illumination light. The headlight assembly controls a light distribution pattern of the illumination light based on the result of detection by the light receiver. Reference is made, for example, to patent reference 1. In the headlight assembly of patent reference 1, a portion of the optical projection system shares a portion of the optical imaging system.

[0003] US 2014 / 0204398A1 describes a lighting device that can detect a deviation of a relative positional relationship between an excitation light source, an optical element, and a light emission section of the lighting device from a relative reference positional relationship.

[0004] EP 3 375 663 A1 describes a headlight device for a vehicle which can prevent an increase in the size of the headlight unit in the direction of the vehicle's width and prevent an impairment of the vehicle's external appearance. REFERENCE ON THE STATE OF THE TECHNOLOGY PATENT REFERENCE

[0005] Patent reference 1: JP 2019 - 64 371 A SUMMARY OF THE INVENTION; PROBLEM TO BE SOLVED BY THE INVENTION

[0006] However, in the headlight device of patent reference 1, the rays incident on the light receiver also contain peripheral rays that are embedded in the incident light and move at positions far from an optical axis. The problem is therefore that aberration occurs in the image produced on the light receiver, and the detection accuracy for incident light at the light receiver decreases.

[0007] One objective of the present disclosure is to provide a headlight device having increased detection accuracy for incident light in the light receiver. MEANS TO SOLVENT THE PROBLEM

[0008] This problem is solved by the subject matter with the features according to the independent claim. Advantageous embodiments of the invention are the subject of the figures, the description, and the dependent claims. A headlight device according to one aspect of the present disclosure comprises a first optical system that emits first light in a predetermined emission direction, and a second optical system comprising a light receiver and a first optical part that is incident on the second light, which propagates in an incident direction opposite to the emission direction. A portion of an optical axis of the first optical system coincides with a portion of an optical axis of the second optical system in the emission direction.The first optical part includes an aperture section that adjusts the diameter of the second light propagating through the second optical system towards the light receiver to be smaller than the diameter of the second light entering the second optical system. IMPACT OF THE INVENTION

[0009] According to the present disclosure, a headlight device with increased detection accuracy for incident light can be provided in the light receiver. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a side view schematically representing a main configuration of a headlight assembly according to a first embodiment. Fig. Figure 2 is a top view which schematically represents the main configuration of the headlight assembly according to the first embodiment. Fig. Figure 3 is a perspective view that schematically illustrates the main configuration of the headlight assembly according to the first embodiment. Fig. 4 is a diagram that shows a configuration of a Fig. 1, Fig. 2 to Fig. 3 represents the light source part shown. Fig. 5 is a diagram that shows a configuration of a Fig. 1, Fig. 2 to Fig. 3 represents the light receiver shown. Fig. Figure 6 is a side view that schematically represents a main configuration of a headlight assembly according to a first modification of the first embodiment. Fig. Figure 7 is a side view that schematically represents a main configuration of a headlight assembly according to a second modification of the first embodiment. Fig. Figure 8 is a side view schematically representing a main configuration of a headlight assembly according to a third modification of the first embodiment. Fig. Figure 9 is a side view schematically representing a main configuration of a headlight assembly according to a fourth modification of the first embodiment. Fig. Figure 10 is a perspective view that schematically represents a main configuration of a headlight assembly according to a fifth modification of the first embodiment. Fig. Figure 11 is a perspective view schematically representing a main configuration of a headlight assembly according to a sixth modification of the first embodiment. Fig. Figure 12 is a diagram showing an example of a spot diagram of light incident on the light receiver of a headlight device according to a second embodiment. Fig. Figure 13 is a diagram that presents an example of a spot diagram of light incident on the light receiver of a headlight device according to a comparative example. Fig. Figure 14 is a perspective view that schematically represents a main configuration of a headlight assembly according to a third embodiment. Fig. Figure 15 is a perspective view that schematically represents a main configuration of a headlight assembly according to a first modification of the third embodiment. Fig. Figure 16 is a perspective view that schematically represents a main configuration of a headlight assembly according to a second modification of the third embodiment. Fig. Figure 17 is a side view schematically representing a main configuration of a headlight assembly according to a fourth embodiment. TYPE AND METHOD OF EXECUTION OF THE INVENTION

[0010] Headlight devices according to the embodiments are described below with reference to the drawings. The following embodiments are only examples, and it is possible to combine embodiments in a suitable manner and to modify each embodiment as appropriate.

[0011] The headlight assembly according to the respective embodiment is, for example, a headlight assembly for a vehicle. The vehicle is, for example, a four-wheeled automobile, a motorized tricycle, a motorcycle, or the like.

[0012] The following is an example where one emission state of the light emitted by the headlight assembly, according to the respective embodiment, is high beam. High beam represents a light emission state for the vehicle's movement. The light emitted by the high beam headlight has a light distribution pattern with a greater range and higher illuminance than the light emitted by a low beam headlight, which represents an emission state for overtaking. Therefore, when the light is emitted by the headlight assembly via the high beam headlight, the driver's field of vision is thus excellently protected. However, when the light is emitted by the high beam headlight, there is a possibility of dazzling the drivers of a vehicle ahead and an oncoming vehicle.To prevent glare, the headlight assembly, according to the respective embodiment, incorporates a control system to adjust the light distribution pattern, such as ADB (Adaptive Driving Beam) control. In the headlight assembly according to the respective embodiment, the light distribution pattern of the light emitted by the high-beam headlight is adjusted so that the emitted area of ​​the light matches a target area (for example, an area that excludes the vehicle ahead and the oncoming vehicle).

[0013] For easier understanding of the description, the drawings show the coordinate axes of an orthogonal xyz coordinate system. The axes shown in the drawings are explained below. An x-axis is a coordinate axis that runs parallel to a transverse direction of the vehicle. More precisely, an x-axis direction is a latitude direction of the vehicle. When viewed head-on from a forward direction of the vehicle, a direction to the left is a +x-axis direction and a direction to the right is a -x-axis direction. A y-axis is a coordinate axis that runs parallel to an up / down direction of the vehicle. An upward direction of the vehicle is a +y-axis direction, and a downward direction of the vehicle is a -y-axis direction. More precisely, a +y-axis side of the vehicle is the sky side and a -y-axis side of the vehicle is the road surface side.A z-axis is a coordinate axis orthogonal to both the x-axis and the y-axis. The z-axis direction is the direction of movement of the vehicle. In the following description, a "+z-axis direction" is also referred to as the "forward direction". (First embodiment) (Headlight configuration)

[0014] Fig. Figure 1 is a side view schematically representing a main configuration of a headlight device 100 according to a first embodiment. Fig. Figure 2 is a top view which schematically represents the main configuration of the headlight assembly 100 according to the first embodiment. Fig. Figure 3 is a perspective view schematically illustrating the main configuration of the headlight assembly 100 according to the first embodiment. The first embodiment describes an example in which the headlight assembly 100 comprises a single headlight module. Therefore, the headlight assembly 100 will also be referred to as a "headlight module" in the following description. However, the headlight assembly 100 can also comprise a plurality of headlight modules.

[0015] As in the Fig. 1, Fig. 2 to Fig. As shown in Figure 3, the headlight assembly 100 comprises a light source part 10, a light receiver 20, and a beam splitter 30 as a first optical part. Furthermore, the configuration of the headlight assembly 100 is not limited to that shown in the Fig. 1, Fig. 2 to Fig. The configuration shown in 3 is limited, but can also be configured in one of the Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10 to Fig. The configuration shown is 11, which will be explained later.

[0016] The light source part 10 is one of the elements that form an optical projection system 101 of the headlight assembly 100. The optical projection system 101 has an optical axis C1 as a first optical axis and emits light L1 as the first light in a predetermined emission direction. In the first embodiment, the emission direction is the +z-axis direction, which is a direction along the optical axis C1. The configuration of the light source part 10 is described in more detail later.

[0017] The light receiver 20 and the beam splitter 30 are elements that form an optical imaging system 102. The light receiver 20 is a light detector that detects incident light L2 as a second light that propagates in an incident direction (in the first embodiment in the -z-axis direction) opposite to the emission direction. In the Fig. 1, Fig. 2 to Fig. Figure 3 is an optical axis of the light receiver 20, designated as optical axis C20. The configuration of the light receiver 20 will be described later.

[0018] The beam splitter 30 emits the light L1 in the emission direction and guides the incident light L2 to the light receiver 20. In the first embodiment, the beam splitter 30 reflects a central luminous flux L20, which is part of the incident L2, and emits the reflected light as light L21, which drives the light receiver 20. The central luminous flux L20 is a luminous flux contained within the incident light L2 and includes a central ray of the incident light L2. Furthermore, the central luminous flux L20 can also be described as a beam of rays contained within the incident light L2 and propagating along the optical axis C1 or in a region in the vicinity of the optical axis C1 (hereinafter also referred to as a "paraxial region").The central luminous flux L20 can contain rays that move parallel to the optical axis C1 and rays that do not move parallel to the optical axis C1, in the paraxial region of the optical axis C1.

[0019] The beam splitter 30 comprises a central part 32a as an aperture element. The central part 32a is arranged on the optical axis C1 and ensures that the diameter of the light L21 propagating through the optical imaging system 102 towards the light receiver 20 is smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 102. The central part 32a is positioned on the beam splitter 30 to cover the area where, for example, the central light flux L20 arrives. Various configurations of the beam splitter 30 are described later. (Light source part)

[0020] Fig. 4 is a diagram showing the configuration of the in Fig. 1, Fig. 2 to Fig. 3 shows the light source part 10. Fig. 4 is a diagram of the in Fig. 1, Fig. 2 to Fig. 3. Light source part 10 shown, viewed from a position on the +z-axis side. As in Fig. As shown in Figure 4, the light source component 10 can, for example, comprise a variety of light-emitting elements 11. The light-emitting element 11 is a solid-state light source. This solid-state light source is a directional light source, such as a semiconductor light source like a light-emitting diode (LED). As another example of a solid-state light source, the light-emitting element 11 could also be an organic electroluminescent light source or a light source that emits excitation light from a fluorescent material, causing the fluorescent material to emit light. The light-emitting element 11 should be an LED because LEDs are small, easy to use in an array, offer high luminance, have a low impact on living organisms, and are inexpensive.

[0021] In the following description, a surface of the light-emitting element 11 facing the +z-axis direction is referred to as a light-emitting surface 12. The light source part 10 comprises one or a plurality of light-emitting surfaces 12. If the light source part 10 comprises a plurality of light-emitting surfaces 12, the light source part 10 comprises, for example, N light-emitting surfaces 12 arranged in a specified orientation. N is a positive integer, which in the Fig. Example 5, as shown in section 4, is shown in the example. In the example shown in the example 4, the following example is shown: Fig. In the example shown in 4, the arrangement direction of the multitude of light-emitting surfaces 12 is the x-axis direction. In the example shown in Fig. In the example shown in Figure 4, the plurality of light-emitting surfaces 12 are arranged linearly in a row. Furthermore, the plurality of light-emitting surfaces 12 arranged in the X-axis direction are also referred to as 12a, 12b, 12c, 12d, and 12e in the following description. Additionally, the number of light-emitting surfaces 12 on the light source part 10 can also be one, as mentioned above. The light source part 10 can also include a configuration for adjusting the light distribution, such as a movable light-blocking plate (not shown).

[0022] The shape of the light-emitting surface 12, viewed in the z-axis direction, is, for example, a rectangular shape. Fig. 4 is the length of a side S12 of the light-emitting surface 12 extending in the x-axis direction, equal to the length of a side S11 of the light-emitting surface 12 extending in the y-axis direction. More specifically, in Fig. 4. The shape of the light-emitting surface 12 is a square shape. However, the shape of the light-emitting surface 12 is not limited to a square shape, but can also have another rectangular shape, such as a non-square rectangular shape, or another shape, such as a circular shape. (Projection / imaging dual-function lens)

[0023] The headlight assembly 100 can have a lens as a second optical component. More precisely, the headlight assembly 100 can have at least one lens. As in the Fig. 1, Fig. 2 to Fig. As shown in Figure 3, the headlight assembly 100 can, for example, have a projection / imaging dual-function lens 50. The projection / imaging dual-function lens 50 is arranged on an optical path of the light L1, which propagates in the emission direction, and on an optical path of the incident light L2, which propagates in the incidence direction. Furthermore, the headlight assembly 100 can also be operated without the lens shown in Figure 3. Fig. The projection / imaging dual-function lens 50 shown and explained later will be implemented.

[0024] The projection / imaging dual-function lens 50 has a function of projecting the light L1 emitted by the light source part 10, and a function of causing the externally incident light L2 to form an image on the light receiver 20 as the detection light. The projection / imaging dual-function lens 50 is, for example, a lens with positive refractive power. The projection / imaging dual-function lens 50 can be either a spherical lens or an aspherical lens. In the first embodiment, the projection / imaging dual-function lens 50 consists of a single lens. The projection / imaging dual-function lens 50 can also be formed from a lens group comprising a plurality of lenses.In the case where the projection / imaging dual-function lens 50 is formed from a lens group, the light utilization efficiency decreases with an increase in the number of lenses, and therefore it is desirable for the projection / imaging dual-function lens 50 to be formed from two lenses. Therefore, it is desirable for the projection / imaging dual-function lens 50 to be formed from two or more lenses. The projection / imaging dual-function lens 50 is, for example, formed from transparent resin or the like. Furthermore, in the first embodiment, the second optical part, which projects the light L1 emitted by the light source part 10 in the forward direction, can also be formed by a combination of the projection / imaging dual-function lens 50 and a reflecting mirror.

[0025] The light L1 entering the projection / imaging dual-function lens 50 passes through it and is emitted in the forward direction in the direction of a predefined emission area. Here, the "predefined emission area" is a predefined region on an emission surface 90 located at a position on the +z-axis side relative to the projection / imaging dual-function lens 50. The emission surface 90 is a virtual projection surface onto which the light distribution pattern of the light L1 is projected.

[0026] In the Fig. 1, Fig. 2 to Fig. In section 3, an optical axis of the projection / imaging dual-function lens 50 is designated as optical axis C5, and an optical axis of the light source part 10 is designated as optical axis C10. The optical axis C10 of the light source part 10 and the optical axis C5 of the projection / imaging dual-function lens 50 lie on the same straight line. More precisely, the optical axis C10 and the optical axis C5 coincide. (Beam splitter)

[0027] Next, the configuration of the beam splitter 30 is described. The beam splitter 30 is an optical element that divides the optical path of the externally incident light L2 by reflecting a portion of the incident light L2 onto a light-reflecting surface 32 having a predetermined reflectivity. The beam splitter 30 can, for example, be formed from a dichroic mirror. The beam splitter 30 transmits the incident light L1 and emits the light in the +z-axis direction. In the first embodiment, the light source part 10 is arranged at a position on the -z-axis side relative to the beam splitter 30. Thus, the beam splitter 30 emits the light L1 entering from the -z-axis side in the emission direction (more precisely, in the +z-axis direction) as the illumination light.

[0028] Furthermore, the light receiver 20 is positioned on the -y-axis side relative to the beam splitter 30. The light receiver 20 can also be positioned on the +y-axis side relative to the beam splitter 30. The beam splitter 30 directs the incident light L2, which falls onto it via the projection / imaging dual-function lens 50, to the light receiver 20. In particular, the beam splitter 30 emits the incident light L2, which propagates in the direction of incidence (i.e., in the -z-axis direction), as the light L21, which propagates towards the light receiver 20.

[0029] The beam splitter 30 has a light-transmitting surface 33 that transmits the light L1. In this way, the beam splitter 30 can have the property of transmitting light L1, that is, optical transparency. Furthermore, the beam splitter 30 has the light-reflecting surface 32 that reflects the incident light L2. In the Fig. In the example shown in Figure 1, the angle θ of the light-reflecting surface 32 with respect to the optical axis C1 is 45 degrees. The angle θ is not limited to 45 degrees but can be set to a different value. The incident light L2 reflected by the light-reflecting surface 32 propagates in the -y-axis direction as the light L21, which is directed towards the light receiver 20. In the first embodiment, the light-reflecting surface 32 and the light-transmitting surface 33 are parallel to each other. Furthermore, the light-reflecting surface 32 and the light-transmitting surface 33 can also be non-parallel to each other, as shown in Figure 1. Fig. 17 is shown, which will be explained later.

[0030] As in Fig. As shown in Figure 3, the light-reflecting surface 32 of the beam splitter 30 comprises the central part 32a as the aperture portion. The central part 32a is arranged on the optical axis C1. The central part 32a reflects the central light flux L20 as part of the incident light L2 and directs the central light flux L20 to the light receiver 20. Accordingly, the beam of light L21 incident on the light receiver 20 is formed by rays that move in the paraxial region of the optical axis C1. Moreover, the central part 32a ensures that the diameter of the light L21 propagating through the beam splitter 30 towards the light receiver 20 is smaller than the diameter of the incident light L2 at the entrance to the projection / imaging dual-function lens 50. Therefore, it is unlikely that peripheral rays L22 (see Figure 3) Fig. 1) The particles contained in the incident light L2, which are located at positions far from the optical axis C1, strike the light receiver 20, thus reducing aberration of the image produced on the light receiver 20. This increases the detection accuracy of the incident light L2 in the light receiver 20.

[0031] The light-reflecting surface 32 of the beam splitter 30 further comprises a peripheral part 32b, which is arranged on an outer surface relative to the central part 32a. The peripheral part 32b transmits the light L1 and reflects the incident light L2. The reflectivity of the peripheral part 32b is lower than the reflectivity of the central part 32a. This feature allows the incidence of the peripheral rays L22 contained in the incident light L2 (see Fig. 1) are inhibited on the light receiver 20. In other words, it is likely that in the incident light L2, the light L21, which is reflected by the central part 32a, will fall on the light receiver 20. Accordingly, the aberration of the image produced on the light receiver 20 is reduced, which can increase the detection accuracy of the incident light L2 in the light receiver 20.

[0032] The central part 32a can, for example, be coated with a metal vapor deposition coating or a dielectric coating of a beam splitter. The peripheral part 32b can, for example, be coated with an AR (anti-reflective) coating. Alternatively, the edge region 32b can also be applied without an AR coating. The shape of the central part 32a is, for example, circular. The shape of the central part 32a is not limited to a circular shape but can also be other. Furthermore, a multitude of reflective areas with different reflectances can be continuously formed on the light-reflecting surface 32, so that the reflectance increases smoothly as the position moves from an outer edge of the beam splitter 30 towards the optical axis C1.Furthermore, a multitude of reflective areas can be individually formed on the light-reflecting surface 32, such that the reflectivity gradually increases as the position moves from the outer edge of the beam splitter 30 towards the optical axis C1. From the perspective of efficiently guiding the incident light L2, which propagates in the vicinity of the optical axis to the light receiver 20, it is desirable to utilize the configuration in which a multitude of reflective areas, differing in reflectivity, are continuously formed on the light-reflecting surface 32, so that the reflectivity increases smoothly as the position moves towards the optical axis C1. (Light receiver)

[0033] Next, the configuration of the light receiver 20 will be explained. The light receiver 20 is arranged in the z-axis direction between the light source part 10 and the projection / imaging dual-function lens 50. The light receiver 20 detects the incident light L2, which is emitted by a predefined light-receiving area located in the forward direction and falls upon it via the projection / imaging dual-function lens 50 and the beam splitter 30. The incident light L2 is the detection light detected by the light receiver 20. Here, the "predefined light-receiving area" is a predefined area located at a position on the +z-axis side relative to the projection / imaging dual-function lens 50 and encompasses at least the "predefined emission area" mentioned above.For example, if a light-emitting object is located within the area illuminated by light L1, which is on the +z-axis side relative to the projection / imaging dual-function lens 50, the incident light L2 can be light emitted by the object. For example, if an oncoming vehicle is in the specified light-receiving area in the forward direction, the incident light L2 can be the light emitted by a headlight of the oncoming vehicle. If a preceding vehicle is in the specified light-receiving area in the forward direction, the incident light L2 can be the light emitted by a taillight of the preceding vehicle.If a light-reflecting object is located in the area emitted with light L1, which is on the +z-axis side relative to the projection / imaging dual-function lens 50, the incident light L2 can be light reflected from the object. For example, if a pedestrian wearing reflective material, a road surface, a guardrail coated with reflective material, or the like is present in the specified light-receiving area in the forward direction, the incident light L2 can be light reflected from the pedestrian, the road surface, or the guardrail.As described above, the object as a light-emitting point of the incident light L2 can be any object (a road surface, an oncoming vehicle, a vehicle ahead, a pedestrian or the like) that is located on the +z-axis side relative to the projection / imaging dual-function lens 50.

[0034] Fig. 5 is a diagram that shows the configuration of the in Fig. 1, Fig. 2 to Fig. 3 shows the light receiver 20. Fig. 5 is a diagram of the one in the Fig. 1, Fig. 2 to Fig. 3. Light receiver 20 shown, viewed from a position on the - y-axis side. As in Fig. As shown in Figure 5, the light receiver 20 comprises a plurality of light-receiving elements 21. The light-receiving element 21 is, for example, a semiconductor element that converts the energy of the received light L21 into an electrical signal. The light-receiving element 21 is, for example, a photodiode, a CCD (Charge Coupled Device) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like. The light receiver 20 can be a line sensor with a plurality of light-receiving elements 21. In the following description, a surface of the light-receiving element 21 pointing in the -y-axis direction is referred to as a light-receiving surface 22.

[0035] The light receiver 20 comprises a plurality of light-receiving surfaces 22 arranged in the x-axis direction. In the following description, the plurality of light-receiving surfaces 22 arranged in the x-axis direction are also referred to as the light-receiving surfaces 22a, 22b, 22c, 22d, and 22e. The light receiver 20 comprises M light-receiving surfaces 22 arranged in a direction corresponding to the arrangement direction of the plurality of light-emitting surfaces 12 (see Figure 1). Fig. 4) N ​​is a positive integer that is in the Fig. Example 5 is shown. The “direction corresponding to the arrangement direction of the plurality of light-emitting surfaces 12” here means either a direction parallel to the arrangement direction of the plurality of light-emitting surfaces 12 or a direction that is not parallel to the arrangement direction of the plurality of light-emitting surfaces 12 but is inclined. In the Fig. In the example shown in Figure 5, the plurality of light-receiving surfaces 22 are arranged in the x-axis direction parallel to the arrangement direction of the plurality of light-emitting surfaces 12. Furthermore, in the first embodiment, the number M of the plurality of light-receiving surfaces 22 is equal to the number N of the plurality of light-emitting surfaces 12, which are arranged in Fig. Figure 4 is shown. In the first embodiment, the plurality of light-receiving surfaces 22 and the plurality of light-emitting surfaces 12 correspond one-to-one.

[0036] As further in Fig. As shown in Figure 5, the multitude of light-receiving surfaces 22 can, for example, be arranged linearly in a row. The shape of the light-receiving surface 22, viewed in the y-axis direction, is, for example, a rectangular shape. In the Fig. In the example shown in Figure 5, the length of a side S21 of the light-receiving surface 22, which extends in the z-axis direction, is longer than the length of a side S22 of the light-receiving surface 22, which extends in the x-axis direction. Fig. 5. The shape of the light-receiving surface 22 is a non-square rectangular shape. With this configuration, an edge in the upward / downward direction of the light-receiving surface 22 (i.e., the z-axis direction) can be secured, and a moving object (for example, another vehicle, a pedestrian, or the like) moving in the forward direction can be accurately detected. Furthermore, the shape of the light-receiving surface 22 is not limited to the non-square rectangular shape but can also be another rectangular shape, such as a square shape. Additionally, the shape of the light-receiving surface 22 is not limited to the rectangular shape but can also be another shape, such as a circular shape. (Light distribution control unit)

[0037] The headlight assembly 100 also includes a light distribution control unit 40, which is connected to the light source part 10 and the light receiver 20. The light distribution control unit 40 causes the light source part 10 to adjust the light distribution pattern of the light L1 based on a detection signal that corresponds to the light L21 detected by the light receiver 20.

[0038] For example, the light distribution control unit 40 assesses whether or not the intensity of the light L21 emitted by each of the multitude of light-receiving surfaces 22 (see Fig. 5) is detected, is greater than or equal to a predefined threshold. If then the intensity of the light L21, which is emitted by at least one (for example, the one in Fig. 5 light-receiving surface 22c) shown, the multitude of light-receiving surfaces 22 is detected and is judged to be greater than or equal to the threshold value, the light distribution control unit 40 controls the light-emitting surfaces 12 (see Fig. 4) of the light source part 10. In particular, the light distribution control unit 40 performs a control to stop light emission at the light-emitting surface 12c corresponding to the light-receiving surface 22c where the light L21 is detected with an intensity greater than or equal to the threshold value, and to start light emission at the other light-emitting surfaces 12a, 12b, 12d, and 12e from the plurality of light-emitting surfaces 12. With this method, it is possible to cause the light source part 10 to adjust the light distribution pattern of the light L1. In the first embodiment, the detection accuracy of the light L21 in the light receiver 20 was increased. Therefore, the light distribution pattern of the light L1 is correctly applied to the target illumination area, and the driver's field of vision in the vehicle equipped with the headlight device 100 can be excellently protected.

[0039] The light distribution control unit 40 is a control circuit that is, for example, composed of integrated semiconductor circuits. The light distribution control unit 40 can also consist of a processor that executes a program stored in memory. (Optical projection system and optical imaging system)

[0040] The following describes optical systems realized by combinations of the light source part 10, the light receiver 20, the beam splitter 30, and the projection / imaging dual-function lens 50, which are components of the headlight module. In the first embodiment, the light source part 10, the beam splitter 30, and the projection / imaging dual-function lens 50 form the optical projection system 101 as a first optical system, which emits the light L1 as the illumination light in the forward direction of the vehicle equipped with the headlight module. The light L1 emitted by the light source part 10 passes through the beam splitter 30 and is emitted by the projection / imaging dual-function lens 50 in the forward direction of the vehicle.

[0041] Furthermore, the projection / imaging dual-function lens 50, the beam splitter 30, and the light receiver 20 form the optical imaging system 102 as a second optical system that captures images of the scene in front of the vehicle. The light L2 incident from the outside via the projection / imaging dual-function lens 50 is reflected by the beam splitter 30 and focused onto the light-receiving surface 22 of the light receiver 20 to produce an image. The optical imaging system 102 has an optical axis C2 as a second optical axis. In the first embodiment, the optical projection system 101 and the optical imaging system 102 share the beam splitter 30 and the projection / imaging dual-function lens 50. More precisely, the optical projection system 101 and the optical imaging system 102 have the common optical axis C5 in front of the beam splitter 30.Thus, part of the optical axis C1 of the optical projection system 101 coincides with part of the optical axis C2 of the optical imaging system 102 in the emission direction. (Effect of the first embodiment)

[0042] According to the first embodiment described above, in the headlight assembly 100, a portion of the optical axis C1 of the optical projection system 101 coincides with a portion of the optical axis C2 of the optical imaging system 102 in the emission direction (specifically, in front of the beam splitter 30). Therefore, a process of adjusting the optical axis C1 of the optical projection system 101 and the optical axis C2 of the optical imaging system 102 in the headlight assembly 100 is not necessary. Accordingly, it is simply a matter of making the emission range L1 of the light emitted by the headlight assembly 100 and the incidence range L2 of the light incident on the headlight assembly 100 coincide.

[0043] According to the first embodiment, the optical imaging system 102 of the headlight assembly 100 further comprises the beam splitter 30. The beam splitter 30 includes the central part 32a as the aperture portion, and the central part 32a ensures that the diameter of the light L21 propagating through the optical imaging system 102 (more precisely, the beam splitter 30) towards the light receiver 20 is smaller than the diameter of the incident light L2 at the point of entry into the optical imaging system 102 (more precisely, the projection / imaging dual-function lens 50). Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will fall on the light receiver 20.Accordingly, the aberration of the image produced on the light receiver 20 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 20.

[0044] Furthermore, according to the first embodiment, the projection / imaging dual-function lens 50 is divided between the optical projection system 101 and the optical imaging system 102. This improves the design of the headlight assembly 100. (First modification of the first embodiment)

[0045] In the first embodiment described above, the configuration in which the headlight assembly 100 includes the projection / imaging dual-function lens 50 was described. The headlight assembly 100 can also be implemented with a configuration without the projection / imaging dual-function lens 50. Fig. Figure 6 is a side view schematically showing a main configuration of a headlight assembly 100a according to a first modification of the first embodiment. Fig. 6 is each component that is connected to a Fig. The component shown in section 1 is identical to or corresponds to the same reference symbol as in the original text. Fig. 1 assigned.

[0046] As in Fig. As shown in Figure 6, the headlight assembly 100a comprises the light source part 10, the light receiver 20, and the beam splitter 30. In the first modification of the first embodiment, an optical projection system 101a is formed by the light source part 10 and the beam splitter 30. In the Fig. In the example shown in Figure 6, the light L1 emitted by the light source part 10 is projected in the forward direction after passing the beam splitter 30.

[0047] Furthermore, in the first modification of the first embodiment, an optical imaging system 102a is formed by the beam splitter 30 and the light receiver 20. In the Fig. In the example shown in Figure 6, the externally incident light L2 is directed towards the light receiver 20 after it has been reflected by the beam splitter 30.

[0048] According to the first modification of the first embodiment described above, the beam splitter 30 and the projection / imaging dual-function lens 50 are separated from the optical projection system 101a and the optical imaging system 102a of the headlight assembly 100a. More precisely, a portion of the optical axis C1 of the optical projection system 101a coincides with a portion of the optical axis C2 of the optical imaging system 102a in the emission direction (specifically, in front of the beam splitter 30). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101a and the optical axis C2 of the optical imaging system 102a in the headlight assembly 100a is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 100a and the incidence range L2 of the light incident on the headlight assembly 100a.

[0049] According to the first modification of the first embodiment, the central part 32a causes the diameter of the light L21, which propagates through the optical imaging system 102a (specifically the beam splitter 30) towards the light receiver 20, to be smaller than the diameter of the incident light L2 as it enters the optical imaging system 102a (more precisely, the projection / imaging dual-function lens 50). Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20. Consequently, the aberration of the image produced on the light receiver 20 is reduced, thereby increasing the detection accuracy of the incident light L2 in the light receiver 20.

[0050] Furthermore, according to the first modification of the first embodiment, the optical projection system 101a of the headlight assembly 100a is formed by the light source part 10 and the beam splitter 30, and the optical imaging system 102a is formed by the beam splitter 30 and the light receiver 20. With this configuration, the number of elements forming the optical projection system 101a and the optical imaging system 102a in the headlight assembly 100a is smaller compared to the headlight assembly 100 according to the first embodiment, and thus the headlight assembly 100a can be miniaturized. (second modification of the first embodiment)

[0051] In the first embodiment described above, an example was described in which the headlight assembly 100 comprises the projection-imaging dual-function lens 50 as the second optical part. In a second modification of the first embodiment, an example is described in which the headlight assembly 100 comprises, in addition to the projection-imaging dual-function lens 50 as the second optical part, a condenser lens 60. Fig. Figure 7 is a side view schematically illustrating a main configuration of a headlight assembly 100b according to the second modification of the first embodiment. Fig. 7 is assigned to each component that is part of a larger set of parts. Fig. Component 1 shown is the same as or corresponds to the same reference symbol as in Fig. 1.

[0052] As in Fig. As shown in Figure 7, the headlight assembly 100b comprises the light source part 10, the light receiver 20, the beam splitter 30, the projection / imaging dual-function lens 50 as a first optical element, and the condenser lens 60 as a second optical element. In the second modification of the first embodiment, the headlight assembly 100b comprises a plurality of lenses (namely, the projection / imaging dual-function lens 50 and the condenser lens 60) as the second optical part. In the second modification of the first embodiment, an optical projection system 101b is further formed by the light source part 10, the beam splitter 30, the projection / imaging dual-function lens 50, and the condenser lens 60.

[0053] The condenser lens 60 is arranged on the optical path of the light L1 emitted by the light source part 10, which is directed towards the beam splitter 30. In the Fig. In the example shown in Figure 7, the condenser lens 60 is arranged between the light source 10 and the beam splitter 30. The condenser lens 60 has the function of condensing the light L1 emitted by the light source 10 and focusing the light onto the beam splitter 30. With this function, the condenser lens 60 is able to modify the light distribution pattern of the incident light L1. More precisely, the condenser lens 60 is a light distribution modifying lens that modifies the light distribution pattern of the light L1. In the example shown in Figure 7, the condenser lens 60 is arranged between the light source 10 and the beam splitter 30. Fig. In the example shown, the optical projection system 101b comprises a single condenser lens 60. However, the optical projection system 101b can also comprise a plurality of condenser lenses 60. More precisely, the optical projection system 101b can have one or more condenser lenses 60. Furthermore, the second optical element, which directs the light L1 emitted from the light source part 10 to the beam splitter 30, is also formed by a combination of the condenser lens 60 and a reflecting mirror.

[0054] In Fig. 7 is an optical axis of the condenser lens 60, designated C6. The optical axis C10 of the light source part 10 and the optical axis C6 of the condenser lens 60 lie on the same straight line. More precisely, the optical axis C10 and the optical axis C6 coincide. Incidentally, the headlight assembly 100b can also be implemented if the optical axis C10 and the optical axis C6 do not coincide. For example, the condenser lens 60 has a rotationally symmetric shape about the optical axis C6 as its axis of rotation. The condenser lens 60 can also be a lens with a rotationally asymmetric shape. For example, the condenser lens 60 is an aspherical lens. In this case, the sag values ​​in the x-axis and y-axis directions of the surface of the condenser lens 60 can differ.Furthermore, the sag amount on the +y-axis side relative to the optical axis C6 and the sag amount on the -y-axis side relative to the optical axis C6 can differ. The surface of the condenser lens 60 can be a freeform surface. Additionally, the surface of the condenser lens 60 can be eccentric with respect to the optical axis C6. Furthermore, the surface of the condenser lens 60 can be inclined in a direction orthogonal to the optical axis C6 in the y-axis direction. The condenser lens 60 is made, for example, of a plastic material such as PC (polycarbonate), resin, or glass. While a case in which the headlight assembly 100b contains the projection / imaging dual-function lens 50, in which in . Fig. As described in the example shown in Figure 7, the headlight device 100b can also be implemented without the projection-imaging dual-function lens 50.

[0055] According to the second modification of the first embodiment described above, the beam splitter 30 and the projection / imaging dual-function lens 50 are separated from the optical projection system 101b and the optical imaging system 102 of the headlight assembly 100b. More precisely, a portion of the optical axis C1 of the optical projection system 101b coincides with a portion of the optical axis C2 of the optical imaging system 102a in the emission direction (specifically, in front of the beam splitter 30). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101b and the optical axis C2 of the optical imaging system 102a in the headlight assembly 100b is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 100b and the incidence range L2 of the light incident on the headlight assembly 100b.

[0056] According to the second modification of the first embodiment, the central part 32a further ensures that the diameter of the light L21 propagating through the optical imaging system 102 (more precisely, the beam splitter 30) towards the light receiver 20 is smaller than the diameter of the incident light L2 upon entering the optical imaging system 102 (more precisely, the projection / imaging dual-function lens 50). Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20. Consequently, the aberration of the image produced on the light receiver 20 is reduced, thereby increasing the detection accuracy of the incident light L2 in the light receiver 20.

[0057] According to the second modification of the first embodiment, the optical projection system 101b of the headlight assembly 100b also includes the condenser lens 60, which is arranged on the optical path of the light L1 emitted by the light source 10 and points towards the beam splitter 30. With this configuration, it is possible to project the light L1 in the forward direction after the light distribution pattern of the light L1 has been modified by the condenser lens 60. This increases the degree of freedom in designing the light distribution pattern of the light L1. (third modification of the first embodiment)

[0058] In the first embodiment described above, an example was described in which the headlight assembly 100 has the projection-imaging dual-function lens 50 as the second optical part. In a third modification of the first embodiment, an example is described in which a headlight assembly 100c has, in addition to the projection / imaging dual-function lens 50, an imaging lens 70 as the second optical part. Fig. Figure 8 is a side view schematically illustrating a main configuration of the headlight assembly 100c according to the third modification of the first embodiment. Fig. 8 is assigned to each component that is in Fig. Component 1 shown is the same as or corresponds to the same reference symbol as in Fig. 1.

[0059] As in Fig. As shown in Figure 8, the headlight assembly 100c comprises the light source part 10, the light receiver 20, the beam splitter 30, the projection / imaging dual-function lens 50 as the first optical element, and the imaging lens 70 as a third optical element. In the third modification of the first embodiment, the headlight assembly 100b comprises a plurality of lenses (more precisely, the projection / imaging dual-function lens 50 and the imaging lens 70) as the second optical part. In the third modification of the first embodiment, an optical imaging system 102c is formed by the projection / imaging dual-function lens 50, the beam splitter 30, the imaging lens 70, and the light receiver 20.

[0060] The imaging lens 70 is arranged on the optical path of the light L21, which is directed towards the light receiver 20 via the beam splitter 30. In the Fig. In the example shown in Figure 8, the imaging lens 70 is arranged between the beam splitter 30 and the light receiver 20. The imaging lens 70 has the function of focusing the light L21 reflected from the beam splitter 30 onto the light receiver 20 in order to produce an image. The imaging lens 70 can be either a spherical lens or an aspherical lens.

[0061] In Fig. 8 is an optical axis of the imaging lens 70, also known as an optical axis C7. In the Fig. In the example shown in Figure 8, the optical axis C7 coincides with the optical axis C5 of the projection / imaging dual-function lens 50 on the +z-axis side of the beam splitter 30. In the case where the optical axis C7 and the optical axis C5 coincide, it is easy to direct the central light flux L20, which is contained in the incident light L2 and propagates along the optical axis C1, to the light receiver 20. This reduces the aberration of the image produced on the light receiver 20 and increases the detection accuracy of the incident light L2 in the light receiver 20.

[0062] The imaging lens 70 is made, for example, of a plastic material such as PMMA (polymethyl methacrylate), a resin, or glass. Equipping the optical imaging system 102c with the imaging lens 70 increases the number of optical surfaces that control the light L21 incident on the light receiver 20. This increases the degree of freedom in the design of the optical imaging system 102c. Furthermore, the third optical element, which directs the incident light L2 reflected from the beam splitter 30 to the light receiver 20, can also be formed by a combination of the imaging lens 70 and a reflecting mirror.

[0063] In the Fig. In the example shown in Figure 8, the beam splitter 30 is arranged between the projection / imaging dual-function lens 50 and the imaging lens 70. Accordingly, in the optical imaging system 102c, the beam splitter 30 achieves an effect equivalent to an aperture provided in an ordinary optical imaging system. In particular, the beam splitter 30 is able to restrict the light incident on the light receiver 20 to the central light flux L20, which propagates along the optical axis C1 and in the vicinity of the optical axis C1, more precisely in the paraxial region. This prevents vignetting of rays in the image produced on the light receiver 20. Consequently, the edge darkening on the light-receiving surface of the light receiver 20 can be reduced.

[0064] Furthermore, the optical imaging system 102c is a symmetrical optical system with respect to a plane containing the light-reflecting surface 32 of the beam splitter 30, or an optical system similar to such a symmetrical optical system. With this configuration, distortion of the image produced on the light receiver 20 can be reduced. This allows the edge darkening on the light-receiving surface of the light receiver 20 to be reduced. Moreover, in a case where the spotlight assembly 100c contains the projection / imaging dual-function lens 50, in which in Fig. As described in the example shown in Figure 8, the headlight device 100c can also be implemented without the projection-imaging dual-function lens 50.

[0065] According to the third modification of the first embodiment described above, the beam splitter 30 and the projection / imaging dual-function lens 50 are separated from the optical projection system 101 and the optical imaging system 102c of the headlight assembly 100c. More precisely, a portion of the optical axis C1 of the optical projection system 101 coincides with a portion of the optical axis C2 of the optical imaging system 102c in the emission direction (specifically, in front of the beam splitter 30). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101 and the optical axis C2 of the optical imaging system 102c in the headlight assembly 100c is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 100c and the incidence range L2 of the light incident on the headlight assembly 100c.

[0066] According to the third modification of the first embodiment, the central part 32a causes the diameter of the light L21, which propagates through the optical imaging system 102c (more precisely, the beam splitter 30) towards the light receiver 20, to be smaller than the diameter of the incident light L2 as it enters the optical imaging system 102d (more precisely, the projection / imaging dual-function lens 50). Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20. Consequently, the aberration of the image produced on the light receiver 20 is reduced. This allows the detection accuracy of the incident light L2 in the light receiver 20 to be increased.

[0067] According to the third modification of the first embodiment, the optical imaging system 102c of the headlight assembly 100c also includes the imaging lens 70, which is arranged on the optical path of the light L21 that passes through the beam splitter 30 towards the light receiver 20. This increases the number of optical surfaces that control the light L21 incident on the light receiver 20. This allows for an increase in the degree of freedom in the design of the optical imaging system 102c. (fourth modification of the first embodiment)

[0068] In the first embodiment described above, an example was described in which the headlight assembly 100d comprises the projection / imaging dual-function lens 50. In a fourth modification of the first embodiment, an example is described in which a headlight assembly 100d, in addition to the projection / imaging dual-function lens 50, includes the condenser lens 60 described in the second modification of the first embodiment and the imaging lens 70 described in the third modification of the first embodiment. Fig. Figure 9 is a side view schematically illustrating a main configuration of a headlight assembly 100d according to the fourth modification of the first embodiment. Fig. 9 is assigned to each component that is part of a larger set of parts. Fig. Component 1 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in . Fig. 1.

[0069] As in Fig. As shown in Figure 9, the headlight assembly 100d comprises the light source part 10, the light receiver 20, the beam splitter 30, the projection / imaging dual-function lens 50, the condenser lens 60, and the imaging lens 70. In the fourth modification of the first embodiment, the optical projection system 101d is formed from the light source part 10, the condenser lens 60, the beam splitter 30, and the projection / imaging dual-function lens 50. Furthermore, an optical imaging system 102d is formed by the projection / imaging dual-function lens 50, the beam splitter 30, the imaging lens 70, and the light receiver 20. Thus, the beam splitter 30 and the projection / imaging dual-function lens 50 are shared by the optical projection system 101d and the optical imaging system 102d of the headlight assembly 100d.

[0070] According to the fourth modification of the first embodiment described above, the beam splitter 30 and the projection / imaging dual-function lens 50 are separated from the optical projection system 101d and the optical imaging system 102d of the headlight assembly 100d. More precisely, a portion of the optical axis C1 of the optical projection system 101 coincides with a portion of the optical axis C2 of the optical imaging system 102 in the emission direction (specifically, in front of the beam splitter 30). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101d and the optical axis C2 of the optical imaging system 102d in the headlight assembly 100d is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 100d and the incidence range L2 of the light incident on the headlight assembly 100d.

[0071] According to the fourth modification of the first embodiment, the central part 32a causes the diameter of the light L21 propagating through the optical imaging system 102d (more precisely, the beam splitter 30) towards the light receiver 20 to be smaller than the diameter of the incident light L2 as it enters the optical imaging system 102d (more precisely, the projection / imaging dual-function lens 50). Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20. Consequently, the aberration of the image produced on the light receiver 20 is reduced. This allows the detection accuracy of the incident light L2 in the light receiver 20 to be increased.

[0072] According to the fourth modification of the first embodiment, the optical projection system 101d comprises the condenser lens 60, which is arranged on the optical path of the light L1 emitted by the light source part 10 and directed towards the beam splitter 30, and the optical imaging system 102d comprises the imaging lens 70, which is arranged on the optical path of the light L21 directed through the beam splitter 30 towards the light receiver 20. With this configuration, the degree of freedom in designing the light distribution pattern of the light L1 can be increased, and the degree of freedom in designing the optical imaging system 102d can be expanded. (fifth modification of the first embodiment)

[0073] In the first embodiment described above, an example was described in which the beam splitter 30 comprises the central part 32a, which is arranged on the optical axis C1, and the peripheral part 32b, which is arranged on the outside relative to the central part 32a. In a fifth modification of the first embodiment, an example is described in which the beam splitter 30e comprises only a central part 32e. Fig. Figure 10 is a perspective view schematically representing a main configuration of a headlight assembly 100e according to the fifth modification of the first embodiment. Fig. 10 is assigned to each component that is in Fig. Component 3 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in the other component. Fig. 3.

[0074] As in Fig. As shown in Figure 10, the headlight assembly 100e comprises the light source part 10, the light receiver 20, the beam splitter 30e, and the projection / imaging dual-function lens 50. In the fifth modification of the first embodiment, an optical projection system 101e is formed by the light source part 10, the beam splitter 30e, and the projection / imaging dual-function lens 50, and an optical imaging system 102e is formed by the projection / imaging dual-function lens 50, the beam splitter 30e, and the light receiver 20.

[0075] The optical projection system 101e and the optical imaging system 102e share the beam splitter 30e and the projection / imaging dual-function lens 50. Thus, the optical projection system 101e and the optical imaging system 102e have a common optical axis C5. More precisely, a portion of the optical axis C1 of the optical projection system 101e coincides with a portion of the optical axis C2 of the optical imaging system 102e in the emission direction. Accordingly, it is easy to make the emission range L1 of the light emitted by the headlight assembly 100 and the incidence range L2 of the light incident on the headlight assembly 100 coincide.

[0076] The beam splitter 30e contains the central part 32e as the aperture portion, which is arranged on the optical axis C1. The central part 32e reflects a portion of the incident light L2 (i.e., the central luminous flux L20) and directs the reflected light to the light receiver 20. More precisely, the central part 32e is a light-reflecting part that reflects the central luminous flux L20 contained in the incident light L2 and propagating in the paraxial region.

[0077] Furthermore, in the fifth modification of the first embodiment, the shape of the central part 32e is, for example, circular. Alternatively, the shape of the central part 32a can also be elliptical or another shape. The diameter of the central part 32e is smaller than the diameter of the incident light L2 as it enters the optical imaging system 102e. Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will fall on the light receiver 20. Accordingly, the aberration of the image produced on the light receiver 20 is reduced. This allows the detection accuracy of the incident light L2 in the light receiver 20 to be increased.

[0078] In the fifth modification of the first embodiment, the light L1 emitted by the light source part 10 passes through the central part 32e and also passes through an area on the outside relative to the beam splitter 30e.

[0079] According to the fifth modification of the first embodiment described above, in the headlight assembly 100e, a portion of the optical axis C1 of the optical projection system 101e coincides with a portion of the optical axis C2 of the optical imaging system 102e in the emission direction (more precisely, in front of the beam splitter 30). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101e and the optical axis C2 of the optical imaging system 102e in the headlight assembly 100e is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 100e and the incidence range L2 of the light incident on the headlight assembly 100e.

[0080] According to the fifth modification of the first embodiment, the optical imaging system 102 of the headlight assembly 100e comprises the beam splitter 30e, which reflects a portion of the incident light L2 and directs the reflected light to the light receiver 20. The beam splitter 30e includes the central part 32e as the aperture portion. The central part 32e directs the central luminous flux L20 contained in the incident light L2 to the light receiver and ensures that the diameter of the light L21 propagating through the optical imaging system 102e to the light receiver 20 is smaller than the diameter of the incident light L2 at the point of entry into the optical imaging system 102e. Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20.Accordingly, the aberration of the image generated on the light receiver 20 is reduced. This allows the detection accuracy of the incident light L2 in the light receiver 20 to be increased. (Sixth modification of the first embodiment)

[0081] In the first embodiment described above, an example was provided in which the aperture portion is located in the beam splitter 30, which reflects a portion of the incident light L2 and directs the reflected light to the light receiver 20. A sixth modification of the first embodiment describes an example in which the aperture portion is a separate part from the beam splitter 30. Fig. Figure 11 is a perspective view schematically representing a main configuration of a headlight assembly 100f according to the sixth modification of the first embodiment. Fig. 11 is assigned to each component that is part of a larger structure. Fig. Component 3 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in the other component. Fig. 3.

[0082] As in Fig. As shown in Figure 11, the headlight assembly 100f comprises the light source part 10, the light receiver 20, a first optical part 30f, and the projection / imaging dual-function lens 50. The first optical part 30f comprises a beam splitter 31 and a light-blocking plate 35 as the aperture part. The beam splitter 31 is arranged on the optical axis C1. The beam splitter 31 reflects a portion of the incident light L2, which propagates in the direction of incidence, and directs the reflected light onto the light-blocking plate 35. In the sixth modification of the first embodiment, an optical projection system 101f is formed by the light source part 10, the beam splitter 31, and the projection / imaging dual-function lens 50.Furthermore, in the sixth modification of the first embodiment, an optical imaging system 102f is formed by the projection / imaging dual-function lens 50, the beam splitter 31, the light-blocking plate 35 and the light receiver 20.

[0083] The optical projection system 101f and the optical imaging system 102f share the beam splitter 31 and the projection / imaging dual-function lens 50. Thus, the optical projection system 101f and the optical imaging system 102f have a common optical axis C5 in front of the beam splitter 31. More precisely, a portion of the optical axis C1 of the optical projection system 101f coincides with a portion of the optical axis C2 of the optical imaging system 102f in the emission direction. Accordingly, it is easy to make the emission range L1 of the light emitted by the headlight assembly 100 and the incidence range L2 of the light incident on the headlight assembly 100 coincide.

[0084] The light-blocking plate 35 is a light-blocking element arranged between the beam splitter 31 and the light receiver 20 in the y-axis direction. The light-blocking plate 35 has an opening 35a as its aperture portion. A portion of the light-blocking plate 35, excluding the opening 35a, is a light-blocking part 35b that blocks the peripheral rays L22 contained in the incident light L2 reflected by the beam splitter 31.

[0085] In the Fig. In the example shown in Figure 11, the aperture 35a is located on the optical axis C20 of the light receiver 20. The aperture 35a transmits the central light flux L20 as part of the incident light L2, which is reflected by the beam splitter 31 and travels as light L21 towards the light receiver 20. The aperture 35a is smaller than the diameter of the incident light L2 as it enters the optical imaging system 102f (more precisely, the projection / imaging dual-function lens 50). In this configuration, the aperture 35a ensures that the diameter of the light L21, which propagates through the optical imaging system 102f (more precisely, the light-blocking plate 35) towards the light receiver 20, is smaller than the diameter of the incident light L2 as it enters the optical imaging system 102f (more precisely, the projection / imaging dual-function lens 50).Furthermore, the position of the light-blocking plate 35 is not limited to the position between the beam splitter 31 and the light receiver 20. The light-blocking plate 35 can also be arranged on the +z-axis side relative to the beam splitter 31 (for example, between the beam splitter 31 and the projection / imaging dual-function lens 50). Moreover, in a case where the headlight assembly 100f is located in . Fig. 8 or Fig. The light-blocking plate 35, which is shown in Figure 9, can be provided on the imaging lens 70 or in the vicinity of the imaging lens 70.

[0086] According to the sixth modification of the first embodiment described above, in the headlight assembly 100f, a portion of the optical axis C1 of the optical projection system 101f coincides with a portion of the optical axis C2 of the optical imaging system 102f in the emission direction (specifically, in front of the beam splitter 31). Therefore, the process of adjusting the optical axis C1 of the optical projection system 101f and the optical axis C2 of the optical imaging system 102f in the headlight assembly 100f is unnecessary. Consequently, it becomes simple to align the emission range L1 of the light emitted by the headlight assembly 100f and the incidence range L2 of the light incident on the headlight assembly 100f.

[0087] According to the sixth modification of the first embodiment, the optical imaging system 102f of the headlight assembly 100f includes the light-blocking plate 35 as the aperture portion containing the opening 35a, and the opening 35a is smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 102f. In this configuration, the opening 35a ensures that the diameter of the light L21 propagating through the optical imaging system 102f towards the light receiver 20 is smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 102f. Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 20.Accordingly, the aberration of the image produced on the light receiver 20 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 20. (Second embodiment)

[0088] In the first embodiment described above, the example was described in which the light contained in the incident light L2 and reflected by the central part 32a of the beam splitter 30 falls onto the light receiver 20. In a second embodiment, an example is described in which the area and reflectivity of the central part 32a are specified. Apart from this feature, a headlight assembly according to the second embodiment is the same as the headlight assembly 100 according to the first embodiment. Fig. 1, Fig. 2 to Fig. 3 is therefore referred to in the following description.

[0089] In the second embodiment, the area of ​​the central part 32a is less than or equal to 20% of the area of ​​the light-reflecting surface 32. More precisely, the beam of light L21, upon incident on the light receiver 20, is limited to being less than or equal to 20% of the effective cross-sectional area of ​​the beam of incident light L2 upon entering the optical imaging system 102 (the projection / imaging dual-function lens 50 in which the Fig. 1, Fig. 2 to Fig. (Example 3 shown). Accordingly, the aberration of the image produced on the light-receiving surface of the light receiver 20 can be reduced compared to a configuration where the beam splitter is a half-mirror. Furthermore, in the case where the beam splitter is a half-mirror, the illumination light passing through the optical element and the incident light reflected by the optical element are uniform. In contrast, if the area of ​​the central part 32a is less than or equal to 20% of the area of ​​the light-reflecting surface 32, the amount of light contained in the light L1 and passing through the peripheral part 32b is large, while the amount of light contained in the light L1 and passing around the vicinity of the optical axis C1 is small.Therefore, the maximum luminosity of the light L1 passing through the beam splitter 30 can be set higher than or equivalent to the maximum luminosity of the illumination light when passing through the half-mirror.

[0090] In the second embodiment, the reflectivity of the central part 32a is furthermore greater than 50% and less than or equal to 100%. Accordingly, if a half-mirror is used for the peripheral part 32b, the central luminous flux L20, which is contained in the incident light L2 and propagates in the paraxial region of the optical axis C1, is more likely to fall on the light receiver 20 than in a configuration where the entire beam splitter is a half-mirror.

[0091] Fig. Figure 12 is a diagram showing an example of a spot diagram of the light incident on the light receiver 20 of the headlight device according to the second embodiment. The diagram in Fig. The spot diagram shown in 12 is a spot diagram at an intersection of the light-receiving surface 22 (see Fig. 5) and the optical axis C20 of the light receiver 20. In the Fig. In the spot diagram shown in Figure 12, the RMS radius (Root Mean Square) is 15.338 µm, which indicates a spot size that represents a distribution of intersection points between the light L21 and the light-receiving surface 22 of the light receiver 20.

[0092] Fig. Figure 13 is a diagram illustrating an example of a spot diagram of light incident on the light receiver of a headlight assembly, according to a comparative example. The headlight assembly according to the comparative example differs from the headlight assembly according to the second embodiment in that the optical element is a semi-mirror. The Fig. The spot diagram shown in Figure 13 is a spot diagram at a central position of the light-receiving surface 22, at which the angle of incidence of the ray with respect to the optical axis of the light receiver is 0 degrees. In the Fig. In the spot diagram shown in Figure 13, the RMS radius, which indicates the spot size of the light, is 1451.20 µm. Provided that the area of ​​the central part 32a is less than or equal to 20% of the area of ​​the light-reflecting surface 32 and the reflectivity of the central part 32a is greater than 50% and less than or equal to 100%, the spot size of the image produced on the light-receiving surface 22 can be kept small. The spot size (area) in the headlight device according to the second embodiment is approximately 14%, assuming, for example, that the light-reflecting surface 32 comprises 20% of the area and has a circular shape. If the area of ​​the light-reflecting surface 32 is further reduced, the spot size (area) in the headlight device according to the second embodiment is expected to be less than approximately 14%.

[0093] According to the second embodiment described above, the area of ​​the central part 32a is less than or equal to 20% of the area of ​​the light-reflecting surface 32, and the reflectivity of the central part 32a is greater than 50% and less than or equal to 100%. Under this condition, the aberration of the image produced on the light receiver 20 can be reduced and the detection accuracy of the incident light L2 in the light receiver 20 can be increased. (Third embodiment)

[0094] In the first embodiment described above, an example was described in which the light L1 emitted by the light source part 10 passes through the beam splitter 30 and is emitted in the emission direction, and the incident light L2 is reflected by the beam splitter 30 and falls on the light receiver 20. In a third embodiment, an example is described in which the light L1 emitted by a light source part 310 is reflected by a beam splitter 330 and is emitted in the emission direction, and the incident light L2 passes through the beam splitter 330 and falls on a light receiver 320. Fig. Figure 14 is a perspective view schematically illustrating a main configuration of a headlight assembly 300 according to the third embodiment. Fig. 14 is each component that is in Fig. Component 1 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in . Fig. 1.

[0095] As in Fig. As shown in Figure 14, the headlight assembly 300 comprises the light source part 310, the light receiver 320, the beam splitter 330 as the first optical part, and the projection / imaging dual-function lens 50. The beam splitter 330 is arranged on the optical axis C1. In the third embodiment, an optical projection system 301 is formed by the light source part 10, the beam splitter 330, and the projection / imaging dual-function lens 50, and an optical imaging system 302 is formed by the projection / imaging dual-function lens 50, the beam splitter 330, and the light receiver 320.

[0096] The optical projection system 301 and the optical imaging system 302 share the beam splitter 330 and the projection / imaging dual-function lens 50. Thus, the optical projection system 301 and the optical imaging system 302 share a common optical axis C5 in front of the beam splitter 330. More precisely, a portion of the optical axis C1 of the optical projection system 301 coincides with a portion of the optical axis C2 of the optical imaging system 302 in the emission direction. Therefore, the process of adjusting the optical axis C1 of the optical projection system 301 and the optical axis C2 of the optical imaging system 302 in the headlight assembly 300 is unnecessary. Consequently, it is easy to align the emission range L1 of the light emitted by the headlight assembly 300 and the incidence range L2 of the light incident on the headlight assembly 300.

[0097] In the Fig. In the example shown in Figure 14, the light source part 310 is arranged at a position on the -y-axis side relative to the beam splitter 330. The beam splitter 330 reflects the light L1 incident on the -y-axis side and emits the reflected light towards the +z-axis side as light L3. Alternatively, the light source part 310 can also be arranged at a position on the +y-axis side relative to the beam splitter 330.

[0098] The light receiver 320 is arranged at a position on the -z-axis side relative to the beam splitter 330. The beam splitter 330 transmits the incident light L2 via the projection / imaging dual-function lens 50 and directs the light to the light receiver 320. More precisely, in the third embodiment, the beam splitter 330 reflects the light L1 and emits the light in the emission direction, and transmits the incident light L2 and directs the light to the light receiver 320.

[0099] The beam splitter 330 has a light-reflecting surface 332 that reflects the light L1 and transmits the incident light L2. The light-reflecting surface 332 includes a central part 332a, which is the aperture part. The central part 332a is located on the optical axis C1. The central part 332a is a light transmission part that transmits the central luminous flux L20, which is contained in the incident light L2 and propagates in the paraxial region, and guides the central luminous flux L20 to the light receiver 320. The central luminous flux L20, passing through the central part 332a, propagates in the -z-axis direction like the light L21, which propagates to the light receiver 320.

[0100] The central part 332a guides the central light flux L20 to the light receiver 320 and ensures that the diameter of the light L21 propagating through the optical imaging system 302 to the light receiver 320 is smaller than the diameter of the incident light L2 upon entering the optical imaging system 102. Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 320. Consequently, the aberration of the image produced on the light receiver 320 is reduced, thereby increasing the detection accuracy of the incident light L2 in the light receiver 320.

[0101] The light-reflecting surface 332 further comprises a peripheral part 332b, which is located on the outside relative to the central part 332a and reflects the light L1. The reflectivity of the peripheral part 332b is higher than that of the central part 332a. Accordingly, the peripheral rays L22, which are contained in the incident light L2 and are located at positions away from the optical axis C1, are reflected by the peripheral part 332b. More precisely, it becomes unlikely that the peripheral rays L22 contained in the incident light L2 will pass through the beam splitter 330, and thus it becomes unlikely that the peripheral rays L22 will reach the light receiver 320. Consequently, the aberration of the image produced on the light receiver 320 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 320.

[0102] The central part 332a can, for example, be provided with an AR (anti-reflective) coating. Alternatively, the central part 332a can also be applied without an AR coating. The peripheral part 332b can, for example, be provided with a metal vapor deposition coating or a dielectric coating of a beam splitter. The shape of the central part 332a is, for example, circular. However, the shape of the central part 332a is not limited to circular; it can also be another shape. Furthermore, a multitude of reflective areas with differing reflectances can be continuously formed on the light-reflecting surface 332, so that the reflectance decreases smoothly as the position moves from the outer edge of the beam splitter 330 towards the optical axis C1.Furthermore, a multitude of reflective areas can be formed on the light-reflecting surface 332, such that the reflectivity gradually decreases as the position moves from the outer edge of the beam splitter 330 towards the optical axis C1. From the perspective of efficiently guiding the incident light L2, which propagates in the vicinity of the optical axis C1, to the light receiver 320, it is desirable to employ a configuration in which a multitude of reflective areas, differing in their reflectivity, are continuously formed on the light-reflecting surface 332, so that the reflectivity decreases smoothly as the position moves towards the optical axis C1.

[0103] According to the third embodiment described above, in the headlight assembly 300, a portion of the optical axis C1 of the optical projection system 301 coincides with a portion of the optical axis C2 of the optical imaging system 302 in the emission direction (specifically, in front of the beam splitter 330). Therefore, the process of adjusting the optical axis C1 of the optical projection system 301 and the optical axis C2 of the optical imaging system 302 in the headlight assembly 300 is unnecessary. Consequently, it becomes easy to align the emission range L1 of the light emitted by the headlight assembly 300 and the incidence range L2 of the light incident on the headlight assembly 300.

[0104] According to the third embodiment, the optical imaging system 302 of the headlight assembly 300 further comprises the beam splitter 330, which transmits a portion of the incident L2 light, and the beam splitter 330 includes the central part 332a as the aperture portion arranged on the optical axis C1. The central part 332a guides the central luminous flux L20, which is contained in the incident light L2, to the light receiver 320 and ensures that the diameter of the light L21, which propagates via the optical imaging system 302 to the light receiver 320, is smaller than the diameter of the incident light L2 at the point of entry into the optical imaging system 302. Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will incident on the light receiver 320.Accordingly, the aberration of the image produced on the light receiver 20 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 320. (First modification of the third embodiment)

[0105] In the third embodiment described above, an example was described in which the aperture portion is the light transmission portion of the beam splitter 330, which transmits a portion of the incident light L2 and directs the light to the light receiver 320. In a first modification of the third embodiment, an example is described in which the aperture portion is an opening 330c formed in the beam splitter 330a. Fig. Figure 15 is a perspective view schematically representing a main configuration of a headlight assembly 300a according to the first modification of the third embodiment. Fig. 15 is assigned to each component that is in Fig. Component 14 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in Fig. 14.

[0106] As in Fig. As shown in Figure 15, the headlight assembly 300a comprises the light source part 310, the light receiver 320, the beam splitter 330a and the projection / imaging dual-function lens 50. In the first modification of the third embodiment, an optical projection system 301a is formed by the light source part 310, the beam splitter 330a and the projection / imaging dual-function lens 50, and an optical imaging system 302a is formed by the projection / imaging dual-function lens 50, the beam splitter 330a and the light receiver 320.

[0107] The optical projection system 301a and the optical imaging system 302a share the beam splitter 330a and the projection / imaging dual-function lens 50, and thus have a common optical axis C5 in front of the beam splitter 330a. More precisely, a portion of the optical axis C1 of the optical projection system 301a coincides with a portion of the optical axis C2 of the optical imaging system 302a in the emission direction. Accordingly, it is easy to make the emission range L1 of the light emitted by the headlight assembly 300 and the incidence range L2 of the light incident on the headlight assembly 300 coincide.

[0108] The beam splitter 330a comprises the central part 332a as the aperture portion. The central part 332a includes the aperture 330c, which transmits the central luminous flux L20, a portion of the incident light L2, and directs the central luminous flux L20 to the light receiver 320. Through the aperture 330c, the diameter of the light L21, which propagates via the optical imaging system 302a (more precisely, the beam splitter 330a) towards the light receiver 320, is adjusted to be smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 302a (more precisely, the projection / imaging dual-function lens 50). In the light L1 emitted by the light source portion 310, a central luminous flux L10 passes through the aperture 330c.In the light L1 emitted by the light source part 310, peripheral rays L12 are reflected by the peripheral part 332b of the beam splitter 330a and emitted as the light L3 to the +z-axis side.

[0109] According to the first modification of the third embodiment described above, in the headlight assembly 300a, a portion of the optical axis C1 of the optical projection system 301a coincides with a portion of the optical axis C2 of the optical imaging system 302a in the emission direction (specifically, in front of the beam splitter 330a). Therefore, the process of adjusting the optical axis C1 of the optical projection system 301a and the optical axis C2 of the optical imaging system 302a in the headlight assembly 300a is unnecessary. Consequently, it becomes simple to align the emission range L1 of the light emitted by the headlight assembly 300a and the incidence range L2 of the light incident on the headlight assembly 300a.

[0110] According to the first modification of the third embodiment, the optical imaging system 302a of the headlight assembly 300 comprises the beam splitter 330a, and the beam splitter 330 comprises the central part 332a as the aperture portion arranged on the optical axis C1. The central part 332a comprises the aperture 330c, and the aperture 330c ensures that the diameter of the light L21 propagating through the optical imaging system 302a towards the light receiver 320 is smaller than the diameter of the incident light L2 at the point of entry into the optical imaging system 302a. Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will strike the light receiver 320.Accordingly, the aberration of the image produced on the light receiver 20 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 320. (Second modification of the third embodiment)

[0111] In the third embodiment described above, an example was described in which the aperture portion is provided in the beam splitter 330. In a second modification of the third embodiment, an example is described in which the aperture portion is a part separate from a beam splitter 331b. Fig. Figure 16 is a perspective view schematically illustrating a main configuration of a headlight assembly 300b according to the second modification of the third embodiment. Fig. 16 is assigned to each component that is part of a larger structure. Fig. Component 14 shown is the same as or corresponds to the same component, and is assigned the same reference symbol as in Fig. 14.

[0112] As in Fig. As shown in Figure 16, the headlight assembly 300b comprises the light source part 310, the light receiver 320, a first optical part 330b, and the projection / imaging dual-function lens 50. The first optical part 330b comprises the beam splitter 331b and a light-blocking plate 335 as the aperture part. In the second modification of the third embodiment, an optical projection system 301b is formed by the light source part 310, the beam splitter 331b, and the projection / imaging dual-function lens 50. Furthermore, in the second modification of the third embodiment, an optical imaging system 302b is formed by the projection / imaging dual-function lens 50, the first optical part 330b (i.e., the beam splitter 331b and the light-blocking plate 335), and the light receiver 320.

[0113] The optical projection system 301b and the optical imaging system 302b share the beam splitter 331b and the projection / imaging dual-function lens 50. Thus, the optical projection system 301b and the optical imaging system 302b have a common optical axis C5 in front of the beam splitter 331b. More precisely, a portion of the optical axis C1 of the optical projection system 301b coincides with a portion of the optical axis C2 of the optical imaging system 302b in the emission direction.

[0114] The beam splitter 331b is arranged on the optical axis C1. The beam splitter 331b has the light-reflecting surface 332, which reflects the light L1 and transmits the incident light L2. The beam splitter 331b transmits the incident light L2 and directs the incident light L2 onto the light-blocking plate 335.

[0115] In the Fig. In the example shown in Figure 16, the light-blocking plate 335 is a light-blocking element arranged between the beam splitter 331b and the light receiver 320. The light-blocking plate 335 includes an aperture 335a, which is arranged on the optical axis C1. A portion of the light-blocking plate 335, excluding the aperture 335a, is a light-blocking part 335b, which blocks the peripheral rays L22 contained in the incident light L2 passing through the beam splitter 331b.

[0116] The aperture 335a is smaller than the diameter of the incident light L2 as it enters the optical imaging system 302b. The aperture 335a transmits the central light flux L20 as part of the incident light L2, which travels from the beam splitter 331b towards the light receiver 320. With this configuration, the aperture 335a ensures that the diameter of the light L21 propagating through the optical imaging system 302b towards the light receiver 320 is smaller than the diameter of the light L21 as it enters the optical imaging system 302b. Therefore, it is unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will reach the light receiver 320.Accordingly, the aberration of the image generated on the light receiver 320 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 320.

[0117] According to the second modification of the third embodiment described above, in the headlight assembly 300b, a portion of the optical axis C1 of the optical projection system 301b coincides with a portion of the optical axis C2 of the optical imaging system 302b in the emission direction (specifically, in front of the beam splitter 331a). Therefore, the process of adjusting the optical axis C1 of the optical projection system 301b and the optical axis C2 of the optical imaging system 302b in the headlight assembly 300b is unnecessary. Consequently, it becomes simple to align the emission range L1 of the light emitted by the headlight assembly 300b and the incidence range L2 of the light incident on the headlight assembly 300b.

[0118] According to the second modification of the third embodiment, the optical imaging system 302b of the headlight assembly 300b comprises the first optical part 330b, and the first optical part 330b comprises the light-blocking plate 335 as the aperture portion containing the opening 335a. The opening 335a is arranged on the optical axis C1 and is smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 302b. With this configuration, the opening 335a ensures that the diameter of the light L21, which propagates through the optical imaging system 302 towards the light receiver 320b, is smaller than the diameter of the incident light L2 at the entrance to the optical imaging system 302. Therefore, it becomes unlikely that the peripheral rays L22 contained in the incident light L2, which are located at positions far from the optical axis C1, will strike the light receiver 320.Accordingly, the aberration of the image generated on the light receiver 320 is reduced, which increases the detection accuracy of the incident light L2 in the light receiver 320. (Fourth embodiment)

[0119] In the first embodiment described above, the example was explained in which the light-transmitting surface 33 and the light-reflecting surface 32 of the beam splitter 31 are parallel to each other. In a fourth embodiment, an example is described in which a surface of a beam splitter 430 onto which the light L1 is incident and a surface of the beam splitter 430 onto which the incident light L2 is incident are not parallel to each other. Fig. Figure 17 is a side view schematically illustrating a main configuration of a headlight assembly 400 according to the fourth embodiment. Fig. 17 will be each component that is connected to a Fig. The component shown in point 1 is identical to or corresponds to it, using the same reference symbol as in point 1. Fig. 1 assigned.

[0120] As in Fig. As shown in Figure 17, the headlight assembly 400 comprises the light source part 10, the light receiver 20, the beam splitter 430, and the projection / imaging dual-function lens 50. The beam splitter 430 is arranged on the optical axis C1. In the fourth embodiment, an optical projection system 401 is formed by the light source part 10, the beam splitter 430, and the projection / imaging dual-function lens 50. Furthermore, an optical imaging system 402 is formed by the projection / imaging dual-function lens 50, the beam splitter 430, and the light receiver 20.

[0121] The beam splitter 430 has a first surface 432 onto which the light L1 emitted by the light source part 10 is incident, and a second surface 433 onto which the incident light L2 is incident. In the fourth embodiment, the first surface 432 is a light transmission surface that transmits the light L1 and directs the light onto the projection / imaging dual-function lens 50, and the second surface 433 is a light reflection surface that reflects the incident light L2 and directs the reflected light to the light receiver 20. In the embodiment described in Fig. In the example shown in Figure 17, the optical projection system 401 is an optical path that passes through the beam splitter 430, and the optical imaging system 402 is an optical path that is reflected from the beam splitter 430.

[0122] The first surface 432 and the second surface 433 are not parallel to each other. In the Fig. In the example shown in Figure 17, angle θ1, the first angle formed by the first surface 432 and the optical axis C20 of the light receiver 20, is smaller than angle θ2, the second angle formed by the second surface 433 and the optical axis C20. Thus, the shape of the optical element 430, viewed from the x-axis direction, is wedge-shaped. Furthermore, angles θ1 and θ2 may each have a tolerance.

[0123] In this case, where the optical projection system 401 is an optical path that passes through the beam splitter 430, and the optical imaging system 402 is an optical path that is reflected from the beam splitter 430, as in Fig. As shown in Figure 17, a ghost image of the light L25, emitted from the second surface 433 after entering the interior of the beam splitter 430 and being reflected from the first surface 432, falls on the light-receiving surface of the light receiver 20, in addition to an image of the light L21 contained in the incident light L2 and reflected from the second surface 433. In a case where the optical projection system is an optical path reflected from the beam splitter and the optical imaging system is an optical path passing through the beam splitter, unlike in Fig.17, there is also in the light distribution pattern of the light projected in the emission direction a ghost image of the light emitted from the light-reflecting surface after it has passed through the light-reflecting surface into the interior of the beam splitter and has been reflected from the light-transmitting surface, in addition to the light distribution pattern of the light reflected from the light-reflecting surface of the beam splitter.

[0124] In the fourth embodiment, the angle θ1 formed by the first surface 432 and the optical axis C20 differs from the angle θ2 formed by the second surface 433 and the optical axis C20, and, as mentioned above, angle θ1 is smaller than angle θ2. With this configuration, the image-forming position of the ghost image of light L25 at the light receiver 20 can be made to coincide with the image-forming position of the image of light L21. Accordingly, the ghost image is corrected, and the detection accuracy of the incident light L2 at the light receiver 20 can be further increased.

[0125] Even in the case where the optical projection system is an optical path reflected from the beam splitter and the optical imaging system is an optical path passing through the beam splitter, the light distribution pattern and the ghost image can be superimposed at a sufficiently distant position in the emission direction, since the angle θ1 and the angle θ2 are different from each other.

[0126] According to the fourth embodiment described above, on the beam splitter 430, the first surface 432, onto which the light L1 is incident, and the second surface 433, onto which the incident light L2 is incident, are not parallel to each other. Specifically, the angle θ1 is formed by the first surface 432, and the optical axis C20 is smaller than the angle θ2 formed by the second surface 433 and the optical axis C20. With this configuration, the image-forming position of the ghost image of light L25 at the light receiver 20 can be made to coincide with the image-forming position of the image of light L21. Accordingly, the ghost image is corrected, and the detection accuracy of the incident light L2 at the light receiver 20 can be further increased. DESCRIPTION OF REFERENCE MARK

[0127] 10, 310: Light source part, 11: Light-emitting element, 12: Light-emitting surface, 20, 320: Light receiver, 21: Light-receiving element, 22: Light-receiving surface, 30, 30e, 31, 330, 330a, 331b, 430: Beam splitter, 30f, 330b: First optical part, 32, 332: Light-reflecting surface, 32a, 32e, 332a: Central part 32a (aperture part), 32b, 332b: Peripheral part, 33, 333: Light transmission surface, 35, 335: Light-blocking plate (aperture part), 35a, 330c, 335a: Aperture, 40: Light distribution control unit 50: Projection / imaging dual-function lens, 60: Condenser lens, 70: Imaging lens, 90: Illumination surface, 100, 100a, 100b, 100c, 100d, 100e, 100f, 300, 300a, 300b, 400: Headlight assembly, 101, 101a, 101b, 101d, 101e, 101f, 301, 301a, 301b, 401: Optical projection system, 102, 102a, 102c, 102d, 102e, 302, 302a, 302b, 402: Optical imaging system, 432: First surface, 433: Second surface, C1 C2, C5, C6, C7, C10,C20: optical axis, L1, L3, L21: light, L2: incident light, L20: central light flux.

Claims

[1] Headlight assembly (100, 100a, 100b, 100c, 100d), comprising: a first optical system (101, 101a, 101b, 101d) that emits first light (L1) in a predetermined emission direction; and a second optical system (102, 102a, 102c, 102d) comprising a light receiver (20) and a beam splitter (30), wherein second light (L2) which propagates in an incident direction opposite to the emission direction is incident on the beam splitter (30), wherein a part of an optical axis (C1) of the first optical system (101, 101a, 101b, 101d) coincides with a part of an optical axis of the second optical system (102, 102a, 102c, 102d) in the emission direction, and wherein the beam splitter (30) has a central part (32a) which adjusts the diameter of the second light (L2) propagating through the second optical system (102, 102a, 102c, 102d) towards the light receiver (20) to be smaller than the diameter of the second light (L2) at the entrance to the second optical system (102, 102a, 102c, 102d); wherein the beam splitter (30) emits the first light (L1) in the emission direction and the second light (L2), which propagates in the incidence direction, leads to the light receiver (20), and wherein the central part (32a) is arranged on the optical axis (C1) of the first optical system (101, 101a, 101b, 101d), wherein the central part (32a) reflects a part of the second light (L2) propagating in the direction of incidence, and wherein the central part (32a) directs this part of the second light (L2) to the light receiver (20); wherein the beam splitter (30) further comprises a peripheral part (32b) which is arranged on an outer side relative to the central part (32a), transmits the first light (L1) and reflects the second light (L2), and where the reflectivity of the peripheral part (32b) is lower than the reflectivity of the central part (32a). [2] Headlight device (100, 100a, 100b, 100c, 100d) according to claim 1, wherein the central part (32a) is smaller than the diameter of the second light (L2) at the entrance to the second optical system (102, 102a, 102c, 102d). [3] Headlight assembly (100, 100a, 100b, 100c, 100d) according to claim 1 or 2, wherein at least one of the first optical system (101, 101a, 101b, 101d) and the second optical system (102, 102a, 102c, 102d) has a second optical part (50, 60, 70). [4] Headlight device (100, 100a, 100b, 100c, 100d) according to claim 3, wherein the second optical part (50, 60, 70) comprises a first optical element (50) arranged on an optical path of the first light (L1) propagating in the emission direction and on an optical path of the second light (L2) propagating in the incident direction. [5] Headlight device (100, 100a, 100b, 100c, 100d) according to claim 3 or 4, wherein the first optical system (101, 101a, 101b, 101d) comprises a light source part (10) emitting the first light (L1) and the second optical part (50, 60), and wherein the second optical part (50, 60) comprises a second optical element (60) arranged on an optical path of the first light (L1) emitted by the light source part (10) and directed towards the central part (32a). [6] Headlight device (100, 100a, 100b, 100c, 100d) according to one of claims 3 to 5, wherein the second optical system (102, 102a, 102c, 102d) has the second optical part (70), and wherein the second optical part (70) has a third optical element (70) arranged on an optical path of the second light (L2) which is directed through the central part (32a) to the light receiver (20).

Images