Vehicle headlight

Abstract

A vehicle headlight (10) includes: a first optical unit (70) that irradiates light on a cutoff line (CL), a region below the cutoff line (CL), and a region including a first upper region above the cutoff line (CL); a second optical unit (80) that irradiates light on a region above the cutoff line (CL) in a dimmable manner; and a third optical unit (90) that irradiates light on a region overlapping a portion of the cutoff line (CL), and a region including a third upper region above the cutoff line (CL) and below the first upper region. When a high beam is ON, the vehicle headlight (10) turns ON the first optical unit (70) and the second optical unit (80) and irradiates light on the first upper region to form a first OHS light distribution pattern, and when a low beam is ON, the vehicle headlight turns ON the first optical unit (70) and the third optical unit (90) and irradiates light on the first upper region and the third upper region to form a second OHS light distribution pattern.

Description

Vehicle headlamp

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

[0002] There is known a vehicle headlamp that forms an OHS (Over Head Sign) light distribution pattern above the cut-off line of a low beam light distribution pattern. Patent Document 1 and Patent Document 2 disclose a vehicle headlamp configured not to irradiate light in a region where glare is likely to be given by providing a light shielding portion that shields a part of the light from the light source in order to reduce glare to a vehicle traveling ahead or the like due to the OHS light distribution pattern.

[0003] Japanese Patent Application Laid-Open No. 2014-029772, Japanese Patent Application Laid-Open No. 2007-179994

[0004] Both Patent Document 1 and Patent Document 2 attempt to widen the light shielding region by the light shielding portion so as not to give glare to a vehicle traveling ahead or the like, but the irradiation region becomes narrower accordingly, making it difficult to form a wide OHS light distribution pattern.

[0005] Also, from the viewpoint of not giving glare to a vehicle traveling ahead or an oncoming vehicle, the cut-off line of the low beam light distribution pattern is preferably clear in brightness contrast. On the other hand, when the driver wants to see a dark region in the distance, if the contrast ratio between light and dark is too large, the dark region becomes difficult to see, so a cut-off line with a gentle gradient of light and dark is preferable.

[0006] Therefore, an object of the present disclosure is to provide a vehicle headlamp that is difficult to give glare to a vehicle traveling ahead or the like and forms a wide OHS light distribution pattern.

[0007] A vehicle headlight according to one aspect of the present disclosure comprises: a first optical unit that irradiates light onto a cutoff line, a region including at least a region below the cutoff line, and a region including a first upper region above the cutoff line; a second optical unit capable of irradiating light onto a region including at least a region above the cutoff line, and capable of dimming any region thereof; and a third optical unit that irradiates light onto a region overlapping at least a portion of the cutoff line, and a region including a third upper region above the cutoff line and below the first upper region, wherein when the high beam is on, the first optical unit and the second optical unit are turned on to irradiate light onto the first upper region to form a first OHS light distribution pattern; and when the low beam is on, the first optical unit and the third optical unit are turned on to irradiate light onto the first upper region and the third upper region to form a second OHS light distribution pattern.

[0008] According to this disclosure, the on / off state of the third optical unit is switched depending on whether the high beam is on or the low beam is on. Furthermore, the first OHS light distribution pattern when the high beam is on is formed only by the first upper region of the first optical unit, and the second OHS light distribution pattern when the low beam is on is formed by two illumination regions: the first upper region of the first optical unit and the third upper region of the third optical unit.

[0009] More specifically, when the high beams are on, the first optical unit lights up, so light is shone on the first upper region, but the third optical unit does not light up, so light is not shone on the third upper region. This makes it less likely to cause glare to the vehicle in front caused by the third upper region.

[0010] On the other hand, when the low beam is on, the first optical unit and the third optical unit are lit, so light is irradiated to both the first upper region and the third upper region, forming a second OHS light distribution pattern that is wider in the vertical direction than the first OHS light distribution pattern.

[0011] According to this disclosure, a vehicle headlight is provided that is less likely to cause glare to preceding vehicles and other objects, and that forms a wide OHS light distribution pattern.

[0012] Figure 1 is a block diagram of the vehicle system configuration, including the vehicle headlights. Figure 2 is a cross-sectional view of the overall optical unit of the vehicle headlights. Figure 3 is a partially enlarged cross-sectional view of the front surface of the first secondary lens of the optical unit. Figure 4 is a diagram illustrating the various light distribution patterns emitted by the vehicle headlights. Figure 5 is a diagram illustrating the low beam light distribution pattern and the second OHS light distribution pattern when the low beam is on. Figure 6 is a diagram illustrating the high beam light distribution pattern and the first OHS light distribution pattern when the high beam is on. Figure 7 is a diagram illustrating the OHS light distribution pattern according to a comparative example when the high beam is on.

[0013] The embodiments of this disclosure will be described below with reference to the drawings. For the sake of clarity, the description of components having the same reference numeral as those already described in the description of the embodiments will be omitted. Furthermore, the dimensions of the components shown in these drawings may differ from the actual dimensions of the components for the sake of clarity.

[0014] Furthermore, in the description of this embodiment, for the sake of clarity, the terms "left-right direction," "up-down direction," and "front-back direction" may be mentioned as appropriate. These directions are relative directions set for the vehicle headlight 10 illustrated in Figure 2. Here, the "left-right direction" includes the "left direction" and the "right direction," as well as the vehicle width direction of the vehicle on which the vehicle headlight 10 is mounted. The "up-down direction" includes the "up direction" and the "down direction." The "front-back direction" is the front-back direction of the vehicle, and includes the "forward direction" and the "rear direction." The front-back direction is perpendicular to the left-right direction and the up-down direction. In each figure, the symbol U indicates the upward direction. The symbol D indicates the downward direction. The symbol F indicates the forward direction. The symbol B indicates the rear direction. The symbol L indicates the left direction. The symbol R indicates the right direction. The left-right direction is an example of the horizontal direction.

[0015] (First Embodiment) A vehicle headlight 10 according to the first embodiment will be described with reference to Figures 1 to 7. The vehicle headlight 10 is mounted on the front right and front left sides of the vehicle 1, respectively. The vehicle headlight 10 is configured to form a high beam light distribution pattern PH, a low beam light distribution pattern PL, a first OHS (Over Head Sign) light distribution pattern PO1, and a second OHS light distribution pattern PO2.

[0016] Figure 1 is a block diagram of the system configuration of vehicle 1, including the vehicle headlight 10. As illustrated in Figure 1, vehicle 1 comprises the vehicle headlight 10, a camera 30, a light switch 40, and a vehicle control unit 50.

[0017] The vehicle headlight 10 comprises a lamp control unit 60, a first optical unit 70, a second optical unit 80, and a third optical unit 90. Details of the vehicle headlight 10 will be described later.

[0018] Camera 30 is positioned near the windshield of vehicle 1. Camera 30 is a camera that includes an image sensor such as a CCD (Charge-Coupled Device) or CMOS (Complementary MOS). Camera 30 acquires image data by imaging the area around vehicle 1 (for example, in front of vehicle 1). Camera 30 outputs the image data to vehicle control unit 50.

[0019] The light switch 40 is located near the steering mechanism of the vehicle 1. The light switch 40 is configured to switch the vehicle headlights 10 ON / OFF or to switch the light distribution pattern in response to an operation by the driver of the vehicle 1. When the driver of the vehicle 1 operates the light switch 40, the light switch 40 generates a control signal to illuminate with a light distribution pattern corresponding to the operation and transmits the signal to the vehicle control unit 50.

[0020] The vehicle control unit 50 is configured to control the driving of the vehicle 1. The vehicle control unit 50 is configured to determine the surrounding environment of the vehicle 1 based on surrounding environment information and to transmit the determination result to the lamp control unit 60 of the vehicle headlight 10. The vehicle control unit 50 is composed of, for example, at least one electronic control unit (ECU). The electronic control unit includes, for example, a computer system including one or more processors and one or more memories, and an electronic circuit composed of active elements such as transistors and passive elements.

[0021] The vehicle control unit 50 is configured to perform image analysis on the image data output from the camera 30. The vehicle control unit 50 detects ambient environment information indicating the surrounding environment of the vehicle 1 from the image data and transmits this ambient environment information to the lamp control unit 60 of the vehicle headlight 10. The ambient environment information includes, for example, position information of objects located in front of the vehicle 1 (oncoming vehicles, vehicles ahead, signs, etc.).

[0022] The vehicle control unit 50 transmits a signal to the lamp control unit 60 of the vehicle headlight 10 to control the vehicle headlight 10 based on the control signal from the light switch 40.

[0023] The lamp control unit 60 of the vehicle headlight 10 may have the same hardware configuration as the vehicle control unit 50. The lamp control unit 60 is configured to control the first optical unit 70, the second optical unit 80, and the third optical unit 90 based on surrounding environment information received from the vehicle control unit 50.

[0024] Next, the details of the vehicle headlight 10 will be described. Figure 2 is a cross-sectional view of the overall optical unit of the vehicle headlight 10. As illustrated in Figure 2, the vehicle headlight 10 comprises a first optical unit 70, a second optical unit 80, and a third optical unit 90, and these optical units are housed in a lamp chamber inside the lamp fixture.

[0025] The first optical unit 70 is configured to illuminate a region including the cutoff line and at least the region below the cutoff line. Furthermore, the first optical unit 70 is configured to illuminate a region including a first upper region above the cutoff line. Details of the light distribution pattern illuminated by the first optical unit 70 will be described later.

[0026] The first optical unit 70 includes, for example, a first light source 71, a first primary lens 72, a first secondary lens 73, and a shade 74. The first light source 71 may be composed of, for example, an LED (Light Emitting Diode) element or an LD (Laser Diode) element. The first light source 71 is configured to emit light toward the first primary lens 72.

[0027] The first primary lens 72 is positioned in front of the first light source 71. The first primary lens 72 is configured to convert the light emitted from the first light source 71 into parallel light and emit it towards the first secondary lens 73. The front surface of the first primary lens 72 may be a convex surface that is convex toward the front, and the rear surface of the first primary lens 72 may be a convex surface that is convex toward the rear. The optical axis of the first primary lens 72 is set to be slightly tilted downward compared to the optical axis of the first light source 71 and the optical axis of the first secondary lens 73. This configures the first primary lens 72 to direct a portion of the light from the first light source 71 toward the front end of the shade 74.

[0028] The shade 74 is located between the first primary lens 72 and the first secondary lens 73, and is positioned below the first primary lens 72. The shade 74 is configured to form a cutoff line in which the upper part is blocked from light and light is shone on the lower part. Specifically, the shade 74 has a region that allows light to pass through and a region that does not allow light to pass through. The front end of the shade 74 has a stepped shape that corresponds to the shape of the cutoff line when viewed from the front, and is located near the focal point F of the first secondary lens 73. Furthermore, a reflecting portion 741 is provided at the front end of the shade 74. With this configuration, light that passes above the shade 74 goes directly to the first secondary lens 73, while light guided to the front end of the shade 74 is reflected by the reflecting portion 741 and goes indirectly to the first secondary lens 73. In this way, the reflecting portion 741 of the shade 74 increases the utilization rate of the light flux of the first light source 71.

[0029] The first secondary lens 73 is positioned in front of the first primary lens 72 and the shade 74. The front surface 73F of the first secondary lens 73 may be a convex surface that is convex to the front, and the rear surface 73B of the first secondary lens 73 may be a convex surface that is convex to the rear. The first secondary lens 73 is configured to project the light emitted from the first primary lens 72 into the front area of ​​the vehicle 1.

[0030] Figure 3 is an enlarged cross-sectional view of the front surface 73F of the first secondary lens 73. As shown in Figure 3, the front surface 73F of the first secondary lens 73 is provided with a first optical control surface 731 and a first OHS control surface 732. The first optical control surface 731 is configured to guide the light emitted from the first primary lens 72 to a region below the cutoff line. The first OHS control surface 732 is provided on a portion of the front surface 73F, adjacent to the first optical control surface 731. The first OHS control surface 732 may be provided so as to be sandwiched between the first optical control surfaces 731. The first OHS control surface 732 is configured to guide the light to a first upper region above the cutoff line. The radius of curvature of the first OHS control surface 732 is different from the radius of curvature of the first optical control surface 731.

[0031] Returning to Figure 2, we will continue the description of the second optical unit 80 and the third optical unit 90. The second optical unit 80 is configured to irradiate light to a region that includes at least the region above the cutoff line. Furthermore, the second optical unit 80 can dim any region within the region above the cutoff line. In this specification, the term "dimming" includes at least one of the following: at least a portion of the light emitted from the second optical unit 80 is blocked, and the intensity of the light emitted from the second optical unit 80 is weakened. The second optical unit 80 can irradiate, for example, an ADB (Adaptive Driving Beam) light distribution pattern. The ADB light distribution pattern is a high beam light distribution pattern PH that does not irradiate light to the region where objects such as preceding vehicles or oncoming vehicles are present, and is a light distribution pattern that changes the unirradiated region depending on the presence and location of such objects.

[0032] The second optical unit 80 includes a second light source 81, a second primary lens 82, and a second secondary lens 83. The second light source 81 may be composed of, for example, a plurality of micro-LED light-emitting elements. The lighting state of the plurality of micro-LED light-emitting elements included in the second light source 81 can be changed independently of each other. In other words, in the vehicle headlight 10, the lamp control unit 60 can perform ON / OFF control and brightness adjustment for each of the micro-LED light-emitting elements included in the second light source 81.

[0033] The second primary lens 82 is positioned in front of the second light source 81. The second primary lens 82 is configured to make the light emitted from the second light source 81 parallel and emit it toward the first secondary lens 73 (second secondary lens 83). The front surface of the second primary lens 82 may be a convex surface that is convex toward the front, and the rear surface of the second primary lens 82 may be a convex surface that is convex toward the rear. The second primary lens 82 may be located below the first primary lens 72 and connected to the first primary lens 72.

[0034] The second secondary lens 83 is positioned in front of the second primary lens 82. The second secondary lens 83 is provided as a part of the first secondary lens 73. In other words, the first secondary lens 73 and the second secondary lens 83 are formed as optical elements that are integrally molded with each other. The front surface of the second secondary lens 83 is configured to guide the light emitted from the second primary lens 82 to a region above the cutoff line.

[0035] The third optical unit 90 is configured to emit light so as to overlap with at least a portion of the cutoff line. Furthermore, the third optical unit 90 is configured to emit light to a region that includes a third upper region that is above the cutoff line and below the first upper region. Details of the light distribution pattern emitted by the third optical unit 90 will be described later.

[0036] The third optical unit 90 includes, for example, a third light source 91, a third primary lens 92, and a third secondary lens 93. The third optical unit 90 may further have a third shade 94 between the third primary lens 92 and the third secondary lens 93. The third light source 91 may be composed of, for example, an LED element or an LD element. The third light source 91 is configured to emit light toward the third primary lens 92. The third primary lens 92 is configured to emit light emitted from the third light source 91 toward the third secondary lens 93. The front surface of the third primary lens 92 may be a convex surface that is convex toward the front, and the rear surface of the third primary lens 92 may be a convex surface that is convex toward the rear.

[0037] The third secondary lens 93 is positioned in front of the third primary lens 92. The front surface 93F of the third secondary lens 93 may be a convex surface that is convex to the front, and the rear surface 93B of the third secondary lens 93 may be a convex surface that is convex to the rear. The third secondary lens 93 is configured to project the light emitted from the third primary lens 92 into the front area of ​​the vehicle 1.

[0038] The front surface 93F of the third secondary lens 93 has the same configuration as the front surface 73F of the first secondary lens 73. That is, as shown in Figure 3, the front surface 93F of the third secondary lens 93 is provided with a third light control surface 931 and a third OHS control surface 932. The third light control surface 931 is configured to guide the light emitted from the third primary lens 92 to a region that overlaps with at least a portion of the cutoff line. The third OHS control surface 932 is provided on a portion of the front surface 93F, adjacent to the third light control surface 931. The third OHS control surface 932 may be provided so as to be sandwiched between the third light control surfaces 931. The third OHS control surface 932 is configured to guide the light to a third upper region that is above the cutoff line and below the first upper region. The radius of curvature of the third OHS control surface 932 is different from the radius of curvature of the third light control surface 931.

[0039] Next, with reference to Figure 4, the light distribution patterns emitted from each optical unit will be described. The first optical unit 70 emits light that forms the first light distribution pattern P11 and the first upward light distribution pattern P21. The second optical unit 80 emits light that forms the second light distribution pattern P12. The third optical unit 90 emits light that forms the third light distribution pattern P13 and the third upward light distribution pattern P23. Figure 4 is a diagram illustrating each light distribution pattern emitted by the vehicle headlight 10. In this embodiment, the case where the vehicle 1 is traveling in the right lane will be described. Also, the first light distribution pattern P11, the first upward light distribution pattern P21, the second light distribution pattern P12, the third light distribution pattern P13, and the third upward light distribution pattern P23 illustrated in Figure 4 are shown projected onto a virtual vertical screen located at a predetermined distance in front of the vehicle 1 (for example, 25 m in front of the vehicle 1). Furthermore, the light distribution patterns illustrated in the following figures also show the state as projected onto a virtual vertical screen at a predetermined position in front of the vehicle 1. In addition, Figure 4 shows a V-V line indicating the vertical direction (up and down direction in Figure 4) at the center of the illumination range of the vehicle headlight 10, and an H-H line perpendicular to the V-V line and extending horizontally (left and right direction in Figure 4). Furthermore, the figures illustrating the light distribution patterns from here on also show a V-V line indicating the vertical direction at the center of the illumination range of the vehicle headlight 10, and an H-H line perpendicular to the V-V line and extending horizontally.

[0040] As illustrated in Figure 4, the first light distribution pattern P11 has a cutoff line CL. The first light distribution pattern P11 is illuminated by light emitted from the first light control surface 731 of the first optical unit 70, and the region including the cutoff line CL and the region below the cutoff line CL (the portion with downward sloping hatching in Figure 4) is illuminated.

[0041] The first upper light distribution pattern P21 is irradiated onto a first upper region (a portion with fine diagonal hatching sloping downward to the lower right in FIG. 4) above the cut-off line CL by the light emitted from the first OHS control surface 732 of the first optical unit 70. The first upper light distribution pattern P21 is formed above the H-H line of the virtual vertical screen and above a virtual line LZ whose vertical angular position is 1 degree above the H-H line.

[0042] The second light distribution pattern P12 forms a so-called high beam light distribution pattern PH together with the first light distribution pattern P11. The second light distribution pattern P12 is irradiated by the second optical unit 80 onto a region (a portion with diagonal hatching sloping upward to the upper right in FIG. 4) including at least a region above the cut-off line CL. In this embodiment, the second optical unit 80 is assumed to irradiate an ADB light distribution pattern. For this reason, any region in the second light distribution pattern P12 can be dimmed.

[0043] The third light distribution pattern P13 is irradiated by the light emitted from the third light control surface 931 of the third optical unit 90 so as to overlap substantially the entire cut-off line CL of the first light distribution pattern P11 (a portion with vertical hatching in FIG. 4). Note that the third light distribution pattern P13 may be irradiated so as to overlap only a part of the first light distribution pattern CL. In this embodiment, the third light distribution pattern P13 forms a low beam light distribution pattern PL together with the first light distribution pattern P11.

[0044] The third upper light distribution pattern P23 is irradiated by the light emitted from the third OHS control surface 932 of the third optical unit 90 onto a third upper region (a portion with fine vertical hatching in FIG. 4) above the cut-off line and below the first upper region. The third upper light distribution pattern P23 is formed above the H-H line of the virtual vertical screen and below a virtual line LZ whose vertical angular position is 1 degree above the H-H line.

[0045] Next, with reference to Figures 5 and 6, the low-beam light distribution pattern PL emitted from the vehicle headlight 10 when the low beam is on, and the high-beam light distribution pattern PH emitted from the vehicle headlight 10 when the high beam is on will be explained. Note that "when the low beam is on" refers to the time when the driver of vehicle 1 operates the light switch 40 to emit the low-beam light distribution pattern PL. "When the high beam is on" refers to the time when the driver of vehicle 1 operates the light switch 40 to emit the high-beam light distribution pattern PH. Figure 5 is an example diagram illustrating the low-beam light distribution pattern PL and the second OHS light distribution pattern PO2 when the low beam is on. Figure 6 is an example diagram illustrating the high-beam light distribution pattern PH and the first OHS light distribution pattern PO1 when the high beam is on. Note that the high-beam light distribution pattern PH emitted in this embodiment is an ADB light distribution pattern.

[0046] As illustrated in Figure 5, when the low beam is on, the vehicle headlight 10 illuminates a low beam light distribution pattern PL consisting of a first light distribution pattern P11 and a third light distribution pattern P13 by illuminating the first optical unit 70 and the third optical unit 90. That is, in this embodiment, the low beam light distribution pattern PL includes the third light distribution pattern P13, and the third light distribution pattern P13 is illuminated so as to overlap with the cutoff line CL. Therefore, the area illuminated by the overlapping first light distribution pattern P11 and the third light distribution pattern P13 is brighter than the area illuminated only by the first light distribution pattern P11 and not by the third light distribution pattern P13.

[0047] Furthermore, when the vehicle headlight 10 is illuminated in low beam, the first optical unit 70 illuminates a first upward light distribution pattern P21, and the third optical unit 90 illuminates a third upward light distribution pattern P23. When both the first upward light distribution pattern P21 and the third upward light distribution pattern P23 are formed, a second OHS light distribution pattern PO2, which is relatively wide in the vertical direction, is formed.

[0048] On the other hand, as illustrated in FIG. 6, when the high beam is turned on, the vehicle headlamp 10 irradiates a high beam light distribution pattern PH composed of a first light distribution pattern P11 and a second light distribution pattern P12 by lighting the first optical unit 70 and the second optical unit 80.

[0049] In the example shown in FIG. 6, since there is a preceding vehicle 1B in front of the vehicle 1, the camera 30 outputs imaging data regarding the preceding vehicle 1B to the vehicle control unit 50. The vehicle control unit 50 detects surrounding environment information including the position information of the preceding vehicle 1B from the imaging data output from the camera 30, and transmits the surrounding environment information to the lamp control unit 60. The lamp control unit 60 controls the second optical unit 80 so that light is not emitted toward the preceding vehicle 1B based on the surrounding environment information received from the vehicle control unit 50. For this reason, in the example shown in FIG. 6, the peripheral area of the preceding vehicle 1B is shielded. Thus, when the high beam is turned on, the peripheral area of the preceding vehicle 1B is shielded and the third light distribution pattern P13 is not irradiated, so that the portion C11 of the cut-off line CL located below the preceding vehicle 1B has a distinct brightness difference. That is, the cut-off line CL formed when the low beam selection light distribution pattern PL is irradiated looks blurrier than the cut-off line CL formed when the high beam light distribution pattern PH (ADB light distribution pattern) is irradiated. Note that since a general low beam light distribution pattern is formed by blocking a part of light, usually, the brightness difference of the cut-off line is distinct. For this reason, the cut-off line of the low beam light distribution pattern PL of the present embodiment is also blurrier than the cut-off line of a general low beam light distribution pattern.

[0050] As described above, when the high beam is turned on, the vehicle headlamp 10 lights the first optical unit 70 to irradiate the first upper light distribution pattern P21, but the third optical unit 90 is turned off so that the third upper light distribution pattern P23 is not irradiated. Therefore, when the high beam is turned on, only the first upper light distribution pattern P21 is irradiated, and a first OHS light distribution pattern PO1, which is narrower in the vertical direction than the second OHS light distribution pattern PO2, is formed.

[0051] Figure 7 illustrates an OHS light distribution pattern POZ according to a comparative example. Unlike this embodiment, the OHS light distribution pattern POZ according to the comparative example is formed by a single optical unit. In this case, it is difficult to form a wide OHS light distribution pattern while avoiding glare to the preceding vehicle 1B, etc. This is because attempting to form a wide OHS light distribution pattern POZ with a single optical unit makes it easy to glare the preceding vehicle 1B, etc. Furthermore, if one attempts to widen the non-illuminated area to avoid glare to the preceding vehicle 1B, etc. with a single optical unit, the illuminated area becomes narrower, making it difficult to form a wide OHS light distribution pattern.

[0052] According to this embodiment, the second OHS light distribution pattern PO2 is formed by two optical units, the first optical unit 70 and the third optical unit 90. In other words, the second OHS light distribution pattern PO2, which is wide in the vertical direction, is divided into two parts: a first upper region (first upper light distribution pattern P21) and a third upper region (third upper light distribution pattern P23). The first upper region is illuminated by the first optical unit 70, and the third upper region is illuminated by the third optical unit 90. In addition, by turning the third optical unit 90 on and off, it is possible to switch between the first OHS light distribution pattern PO1, which includes only the first upper region, and the second OHS light distribution pattern PO2, which includes both the first and third upper regions. Therefore, when the high beam is on, only the first OHS light distribution pattern PO1 is formed to reduce glare to the vehicle in front, while when the low beam is on, the second OHS light distribution pattern PO2, which is wide in the vertical direction, can be formed.

[0053] As described above, according to this embodiment, when the low beam is illuminated, the third optical unit 90 illuminates the area so as to overlap with the cutoff line CL formed by the first optical unit 70. As a result, a low beam light distribution pattern PL is formed that is blurred and has good visibility compared to the cutoff line CL formed by the first optical unit 70 alone.

[0054] On the other hand, when the high beams are on, the so-called ADB light distribution pattern is projected, and a distinct cutoff line (CL) is formed. However, since the cutoff line (CL) only appears in the dimmed area, it does not significantly worsen visibility.

[0055] Furthermore, when the high beams are on, the first OHS light distribution pattern PO1 is formed only by the first upper region of the first optical unit 70. Since the third optical unit 90 is not lit when the high beams are on, light is not irradiated into the third upper region. Therefore, it is possible to reduce the glare caused to the vehicle in front due to the third upper region.

[0056] On the other hand, when the low beam is on, the second OHS light distribution pattern PO2 is formed by two illumination regions: a first upper region formed by the first optical unit 70 and a third upper region formed by the third optical unit 90. As a result, the second OHS light distribution pattern PO2 is formed which is wider in the vertical direction than the first OHS light distribution pattern PO1.

[0057] The first optical unit 70 includes a first light source 71, a first primary lens 72, and a first secondary lens 73. The front surface 73F of the first secondary lens 73 is provided with a first light control surface 731 that guides light to a region below the cutoff line CL, and a first OHS control surface 732 that guides light to a first upper region. The third optical unit 90 includes a third light source 91, a third primary lens 92, and a third secondary lens 93. The front surface 93F of the third secondary lens 93 is provided with a third light control surface 931 that guides light to a region overlapping with at least a portion of the cutoff line CL, and a third OHS control surface 932 that guides light to a third upper region.

[0058] In this way, a light control surface and an OHS control surface are provided on the front surface of each of the two secondary lenses. Therefore, according to this embodiment, without increasing the number of parts, each of the two secondary lenses, the first secondary lens 73 and the third secondary lens 93, can easily form multiple light distribution patterns, such as the low beam light distribution pattern PL and the first OHS light distribution pattern PO1 or the second OHS light distribution pattern PO2.

[0059] The radius of curvature of the third OHS control surface 932 is different from the radius of curvature of the third optical control surface 931. Thus, according to this embodiment, by changing the curvature of the front surface 93F of the third secondary lens 93, multiple light distribution patterns can be formed without increasing the number of parts.

[0060] The third upper region formed on the virtual vertical screen is above the H-H line of the virtual vertical screen and below the virtual line LZ, which is located at a vertical angle position of 1 degree above the H-H line. In other words, on the virtual vertical screen, the third upper region is formed in a relatively low region, below the virtual line LZ, which is at a vertical angle position of 1 degree. The third optical unit 90 illuminates this third upper region, which is located in such a relatively low region. Therefore, when the high beam is on, the third optical unit 90 is turned off to reduce glare to the vehicle in front, while when the low beam is on, the third optical unit 90 is turned on to form a relatively wide second OHS light distribution pattern.

[0061] The first optical unit 70 may be a two-dimensional LED array or a micro-LED array. With this configuration, the illumination area of ​​the first optical unit 70 is divided into multiple areas in which any area can independently change its lighting state. The first optical unit 70 can form the first light distribution pattern P11 by lighting some of the LEDs corresponding to the first light distribution pattern P11, or form the first upward light distribution pattern P21 by lighting some other LEDs corresponding to the first upward light distribution pattern P21. The same applies to the second optical unit 80 and the third optical unit 90.

[0062] This application claims priority under Japanese application No. 2024-206139 filed on 27 November 2024, and incorporates all the provisions contained in the said Japanese application.

Claims

1. A vehicle headlight comprising: a first optical unit that irradiates light onto a cutoff line, a region including at least a region below the cutoff line, and a region including a first upper region above the cutoff line; a second optical unit capable of irradiating light onto a region including at least a region above the cutoff line, and capable of dimming any region thereof; and a third optical unit that irradiates light onto a region overlapping at least a portion of the cutoff line, and a third upper region above the cutoff line and below the first upper region, wherein when the high beam is on, the first optical unit and the second optical unit are lit, irradiating light onto the first upper region to form a first OHS light distribution pattern; and when the low beam is on, the first optical unit and the third optical unit are lit, irradiating light onto the first upper region and the third upper region to form a second OHS light distribution pattern.

2. The vehicle headlight according to claim 1, wherein the first optical unit comprises a first light source, a first primary lens, and a first secondary lens, and the front surface of the first secondary lens is provided with a first light control surface for guiding light to the region below the cutoff line and a first OHS control surface for guiding light to the first upper region, and the third optical unit comprises a third light source, a third primary lens, and a third secondary lens, and the front surface of the third secondary lens is provided with a third light control surface for guiding light to the region overlapping with at least a portion of the cutoff line and a third OHS control surface for guiding light to the third upper region.

3. The headlight for a vehicle according to claim 2, wherein the radius of curvature of the third OHS control surface is different from the radius of curvature of the third light control surface.

4. The headlight for a vehicle according to claim 1, wherein the illumination areas of the first optical unit, the second optical unit, and the third optical unit are each divided into a plurality of areas in which any area can independently change the illumination state.

5. The vehicle headlight according to any one of claims 1 to 4, wherein the third upper region formed on a virtual vertical screen positioned at a predetermined distance from the vehicle is formed above the H-H line of the virtual vertical screen and below a virtual line located at a vertical angle position of 1 degree above the H-H line.

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