Lamp unit
The lamp unit addresses the challenge of compact, low-cost design and efficient light distribution by using a light guide with a cutoff line forming section, second optical element, and light control surface to minimize material usage and enhance light guidance efficiency.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- KOITO MFG CO LTD
- Filing Date
- 2025-12-15
- Publication Date
- 2026-07-02
AI Technical Summary
Vehicle lamps with vertically small and horizontally long shapes are demanded due to design requirements, but using materials with excellent heat resistance characteristics for optical elements increases costs, and existing designs struggle to efficiently form desired light distribution patterns while minimizing material usage.
A lamp unit with a light guide that includes a cutoff line forming section, a second optical element, a second reflective surface, and a light control surface to efficiently guide light to a projection lens, reducing material usage and enabling compact, low-cost design.
The lamp unit achieves a vertically compact and cost-effective solution capable of forming desired light distribution patterns by minimizing the amount of material used in the light guide, enhancing light guidance efficiency and reducing material costs.
Smart Images
Figure JP2025043661_02072026_PF_FP_ABST
Abstract
Description
Lamp unit
[0001] The present disclosure relates to a lamp unit.
[0002] Patent Document 1 discloses a lamp unit that forms a light distribution pattern of a desired shape by controlling incident light to a projection lens by a light guide body disposed between a light source and the projection lens. The light guide body includes a first emission surface for emitting light for a low beam light distribution pattern and a second emission surface for emitting light for an additional light distribution pattern added when forming a high beam light distribution pattern.
[0003] Japanese Patent Application Laid-Open No. 2022-94635
[0004] By the way, in recent years, due to design requirements, vehicle lamps having a vertically small and horizontally long shape have been demanded.
[0005] Further, when efficiently making light from a light source incident on one optical element, in order to dispose the optical element near the light source which is a heat generating body, it is necessary to use a material (silicone resin) having excellent heat resistance characteristics for the optical element. However, as the amount of use of such a material having excellent heat resistance characteristics increases, the cost tends to increase accordingly.
[0006] An object of the present disclosure is to provide a lamp unit that is vertically small, low in cost, and capable of forming a desired light distribution pattern.
[0007] A lighting unit according to one aspect of the present disclosure comprises: a first light source that emits light to form a low-beam light distribution pattern including a cutoff line and a high-beam light distribution pattern; a second light source that emits light to form the high-beam light distribution pattern; a projection lens that projects the light emitted from the first light source and the second light source forward; and a light guide that guides the light emitted from the first light source and the second light source to the projection lens, wherein the light guide has: a cutoff line forming section that totally reflects a portion of the light emitted from the first light source to form the cutoff line of the low-beam light distribution pattern; a second optical element that converts the light emitted from the second light source into parallel light; a second reflective surface that totally reflects the parallel light formed by the second optical element so that it passes below the cutoff line forming section and is directed toward the projection lens; and a light control surface provided below the cutoff line forming section that controls the light totally reflected by the second reflective surface to be focused toward the projection lens.
[0008] According to this disclosure, the light guide is provided below the cutoff line forming portion and has a light control surface that controls the light totally reflected by the second reflecting surface to be focused and directed toward the projection lens. Therefore, compared to the case without a light control surface, it is easier to guide the light totally reflected by the second reflecting surface through a narrower region to the projection lens, and the light guide below the cutoff line forming portion can be miniaturized. Consequently, the amount of material used for the light guide can be reduced.
[0009] According to this disclosure, a luminaire unit is provided that is vertically compact, low-cost, and capable of forming a desired light distribution pattern.
[0010] Figure 1 is a longitudinal cross-sectional view illustrating the configuration of a lighting unit according to the first embodiment. Figure 2 is a longitudinal cross-sectional view illustrating the configuration of a lighting unit according to a reference example.
[0011] The embodiments of this disclosure will be described below with reference to the drawings. For the sake of explanation, the dimensions of each component shown in these drawings may differ from the actual dimensions of each component. 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 backward direction. These directions are relative directions set for the lighting unit 1 illustrated in Figure 1, with the direction of light emitted from the lighting unit 1 being defined as the forward direction.
[0012] (First Embodiment) Figure 1 is a longitudinal cross-sectional view illustrating the configuration of a lighting unit 1 according to the first embodiment. In Figure 1, some of the light emitted from the light source is shown as light L1 to L4.
[0013] The lighting unit 1 is mounted on a vehicle headlight and is configured to form a low-beam light distribution pattern and a high-beam light distribution pattern, including a cutoff line.
[0014] As illustrated in Figure 1, the lighting unit 1 comprises a plurality of first light sources 2, a plurality of second light sources 3, a projection lens 4, and a light guide 5.
[0015] Multiple first light sources 2 are arranged side by side in the left-right direction (perpendicular to the plane of the paper in Figure 1). Only one first light source 2 is shown in Figure 1. The first light source 2 is mounted on the wiring board 6 with its light-emitting surface facing diagonally upward and forward. The first light source 2 is, for example, an LED (Light Emitting Diode) element or an LD (Laser Diode) element.
[0016] The first light source 2 is controlled to light up when forming the low-beam and high-beam light distribution patterns. In other words, the light emitted from the first light source 2 is emitted from the luminaire unit 1 as light to form the low-beam and high-beam light distribution patterns.
[0017] Multiple second light sources 3 are arranged side by side in the left-right direction (perpendicular to the plane of the paper in Figure 1). Only one second light source 3 is shown in Figure 1. The second light source 3 is located behind the first light source 2. The second light source 3 is mounted on the wiring board 6 with its light-emitting surface facing diagonally upward and forward. The second light source 3 is, for example, an LED element or an LD element.
[0018] The second light source 3 is controlled to light up when forming the high beam light distribution pattern. In other words, the light emitted from the second light source 3 is emitted from the luminaire unit 1 as light to form the high beam light distribution pattern.
[0019] The projection lens 4 is configured to project light emitted from the first light source 2 and the second light source 3 forward. The projection lens 4 has an optical axis Ax extending in the front-rear direction of the luminaire unit 1, and is configured to form a light distribution pattern by inverting and projecting the image formed on the rear focal plane.
[0020] The light guide 5 is configured to guide the light emitted from the first light source 2 and the second light source 3 to the projection lens 4. The light guide 5 is made of a resin such as silicone resin, acrylic resin, or PC (polycarbonate) resin. The light guide 5 is positioned above the first light source 2 and the second light source 3. The light guide 5 is positioned behind the projection lens 4. Light emitted from the first light source 2 and the second light source 3 enters the light guide 5 from below and emits light forward.
[0021] The light guide 5 has a plurality of first optical elements 51, a cutoff line forming portion 52, a first reflective surface 53, a plurality of second optical elements 54, a second reflective surface 55, a first emission surface 56, a second emission surface 58, and a light control surface 59.
[0022] The first optical element 51 is the part that takes in the light guide 5 from the first light source 2. Multiple first optical elements 51 are arranged side by side in the left-right direction (the direction perpendicular to the plane of the paper in Figure 1). Only one first optical element 51 is shown in Figure 1. The first optical element 51 is positioned opposite the corresponding first light source 2. The first optical element 51 is configured to refract or reflect the light emitted from the first light source 2 to make it parallel light.
[0023] In this embodiment, the first optical element 51 is a TIR (Total Internal Reflection) lens. Specifically, the first optical element 51 has a first incident surface 511, a second incident surface 512, and a reflecting surface 513. The first incident surface 511 is positioned facing the first light source 2. In this embodiment, the first incident surface 511 has a convex shape toward the first light source 2. The second incident surface 512 is provided as a vertical wall surrounding the first incident surface 511. The reflecting surface 513 is provided so as to surround the second incident surface 512. Light incident on the first incident surface 511 from the first light source 2 is refracted by the first incident surface 511 and becomes parallel light toward the first reflecting surface 53. Light incident on the second incident surface 512 from the first light source 2 is reflected by the reflecting surface 513 and becomes parallel light toward the first reflecting surface 53. The parallel light rays traveling from the first incident surface 511 to the first reflection surface 53 and the parallel light rays traveling from the reflection surface 513 to the first reflection surface 53 are parallel to each other.
[0024] The cutoff line forming section 52 is configured to totally reflect a portion of the light emitted from the first light source 2 to form a cutoff line for the low beam light distribution pattern.
[0025] In this embodiment, the light guide 5 has a notched element 57 formed between the first reflective surface 53 and the first emitting surface 56. The notched element 57 extends backward from near the rear focal point F1 of the projection lens 4. In this embodiment, the notched element 57 is a space (opening) formed as a roughly rectangular prism that penetrates in the left-right direction. The space inside the notched element 57 is hollow. The cutoff line forming portion 52 is formed in the notched element 57.
[0026] Specifically, the notched element 57 has an upper surface 57U that extends backward from near the rear focal point F1 of the projection lens 4. The upper surface 57U extends in the front-to-back and left-to-right directions. The upper surface 57U also extends along the optical axis Ax of the projection lens 4. The upper surface 57U is the interface between the cavity (air) of the notched element 57 and the other part (resin), and is formed as a total reflection surface where light from the first reflection surface 53 is totally reflected due to the difference in refractive index between air and resin. In other words, the upper surface 57U forms the cutoff line forming portion 52. The upper surface 57U is configured to have a roughly Z shape when viewed from the front, corresponding to the cutoff line of the low beam light distribution pattern.
[0027] The lower surface 57D of the notched element 57 is the interface between the cavity (air) of the notched element 57 and the other part (resin). Due to the difference in refractive index between air and resin, it is formed as a totally reflective surface where light from the second reflective surface 55 is totally reflected. The lower surface 57D extends in the front-to-back direction. The lower surface 57D is an example of a flat surface.
[0028] The notched element 57 is positioned above the first light source 2 and the second light source 3. Furthermore, the notched element 57 is positioned above the first optical element 51. In other words, the cutoff line forming section 52 is located above the first light source 2, the second light source 3, and the first optical element 51. The notched element 57 is positioned between the first reflective surface 53 and the second reflective surface 55 in the vertical direction.
[0029] The first reflective surface 53 is located on the rear surface 5B of the light guide 5 above the notched element 57. That is, the first reflective surface 53 is located above the cutoff line forming section 52. In the cross-section shown in Figure 1, the first reflective surface 53 is an inclined surface extending diagonally forward and upward. The inclined surface is not limited to a flat surface, but may also be a curved surface. The first reflective surface 53 extends in the left-right direction along the plurality of first optical elements 51. The first reflective surface 53 is configured to totally reflect the parallel light formed by the first optical elements 51 so that it passes above the cutoff line forming section 52 and heads toward the projection lens 4. The first reflective surface 53 is also configured to totally reflect the light from the plurality of first light sources 2. The light distribution patterns from each of the plurality of first light sources 2 are arranged and irradiated in the left-right direction, forming a wide light distribution pattern in the left-right direction.
[0030] The second optical element 54 is the part that takes in the light emitted from the second light source 3 into the light guide 5. The second optical element 54 is configured to refract or reflect the light emitted from the second light source 3 to make it parallel light. The second optical element 54 is located below the notched element 57.
[0031] In this embodiment, the second optical element 54 is a TIR lens. Specifically, the second optical element 54 has a first incident surface 541, a second incident surface 542, and a reflecting surface 543. The first incident surface 541 is positioned facing the second light source 3. In this embodiment, the first incident surface 541 has a convex shape toward the second light source 3. The second incident surface 542 is provided as a vertical wall surrounding the first incident surface 541. The reflecting surface 543 is provided so as to surround the second incident surface 542. Light incident on the first incident surface 541 from the second light source 3 is refracted by the first incident surface 541 and becomes parallel light that travels toward the second reflecting surface 55. Light incident on the second incident surface 542 from the second light source 3 is reflected by the reflecting surface 543 and becomes parallel light that travels toward the second reflecting surface 55. The parallel light rays traveling from the first incident surface 541 to the second reflection surface 55 and the parallel light rays traveling from the reflection surface 543 to the second reflection surface 55 are parallel to each other.
[0032] The second reflective surface 55 is provided on the rear surface 5B of the light guide below the notched element 57. That is, the second reflective surface 55 is located below the cutoff line forming portion 52. In the cross-section shown in Figure 1, the second reflective surface 55 is an inclined surface extending diagonally forward and upward. The second reflective surface 55 extends in the left-right direction along the plurality of second optical elements 54. The second reflective surface 55 is located behind the first reflective surface 53. The second reflective surface 55 is located below the first reflective surface 53. The second reflective surface 55 is configured to totally reflect the parallel light formed by the second optical elements 54 so that it passes below the cutoff line forming portion 52 and heads toward the projection lens 4.
[0033] The first emitting surface 56 is located on the front of the light guide 5. The first emitting surface 56 is configured to emit forward light that has been totally reflected by the first reflecting surface 53. The second emitting surface 58 is located on the front of the light guide 5, below the first emitting surface 56. The second emitting surface 58 is configured to emit forward light that has been totally reflected by the second reflecting surface 55.
[0034] The light control surface 59 is located below the cutoff line forming section 52. The light control surface 59 is located below the lower surface 57D of the notched element 57. Furthermore, the light control surface 59 is located between the second reflective surface 55 and the second emission surface 58 in the front-rear direction. The light control surface 59 is configured to concentrate the light totally reflected by the second reflective surface 55 and control it so that it is directed towards the projection lens 4.
[0035] The light guide 5 integrally comprises a plurality of first optical elements 51, a cutoff line forming portion 52, a first reflective surface 53, a plurality of second optical elements 54, a second reflective surface 55, and a light control surface 59. For example, the light guide 5, in which the first optical elements 51, the cutoff line forming portion 52, the first reflective surface 53, the second optical elements 54, the second reflective surface 55, and the light control surface 59 are integrated, may be formed by resin molding using a mold. For example, the light guide 5, in which the first optical elements 51, the cutoff line forming portion 52, the first reflective surface 53, the second optical elements 54, the second reflective surface 55, and the light control surface 59 are integrated, may be formed by heat fusion or adhesive bonding.
[0036] In the lighting unit 1 configured in this way, when forming a low-beam light distribution pattern, the first light source 2 is turned on, and the second light source 3 is not turned on.
[0037] When light L1 and L2 emitted from the first light source 2 enters the first optical element 51, they are refracted or reflected by the first optical element 51 and travel toward the first reflective surface 53 as parallel light.
[0038] The first reflective surface 53 totally reflects the light L1 and L2 from the first light source 2, which has been made into parallel light by the first optical element 51, towards the rear focal point F1 of the projection lens 4, approximately downward and diagonally forward. The light totally reflected by the first reflective surface 53 heads toward the vicinity of the rear focal point F1 of the projection lens 4. Some of the light L1 heading toward the vicinity of the rear focal point F1 of the projection lens 4 passes over the notched element 57. On the other hand, some of the light L2 that is totally reflected by the first reflective surface 53 and heads toward the vicinity of the rear focal point F1 of the projection lens 4 is totally reflected by the total reflection surface of the cutoff line forming section 52. In the illustrated example, some of the lower part of the light L2 of the light totally reflected by the first reflective surface 53 is totally reflected by the total reflection surface of the cutoff line forming section 52, and an image with the lower part cut off is formed on the rear focal plane of the projection lens 4. The projection lens 4 inverts this image vertically and projects a light distribution pattern with the upper part cut off onto the projection screen. In other words, a low-beam light distribution pattern, including a cutoff line, is formed by the light distribution pattern formed by the light L1 and L2 emitted from the first light source 2.
[0039] On the other hand, when forming a high beam light distribution pattern, both the first light source 2 and the second light source 3 are illuminated.
[0040] When light L3 and L4 emitted from the second light source 3 enters the second optical element 54, they are refracted or reflected by the second optical element 54 and head toward the second reflective surface 55 as parallel light. The second reflective surface 55 causes total internal reflection of the light L3 and L4 from the second light source 3, which has been made into parallel light by the second optical element 54, so that it passes through the light control surface 59 below the cutoff line forming section 52 and heads toward the projection lens 4.
[0041] The second light source 3 is located behind the first light source 2, and the second reflecting surface 55 is located behind and below the first reflecting surface 53. Therefore, the lights L3 and L4 from the second light source 3 that are totally reflected by the second reflecting surface 55 intersect the lights L1 and L2 from the first light source 2 at a position after the lights L1 and L2 from the first light source 2 enter the first optical element 51 and before they enter the first reflecting surface 53.
[0042] The lights L3 and L4 that are totally reflected by the second reflecting surface 55 pass through the light control surface 59 below the cutoff line forming portion 52 before entering the second exit surface 58. By the light control surface 59, the lights L3 and L4 are condensed while passing below the lower surface 57D of the cut-off element 57. An image formed by the lights L3 and L4 condensed by the light control surface 59 is formed on the rear focal plane of the projection lens 4. The projection lens 4 projects an image that is vertically inverted onto the projection screen, projecting a light distribution pattern formed above the cutoff line. A high beam light distribution pattern is formed by the light distribution pattern formed by the light emitted from the first light source 2 and the light distribution pattern formed by the light emitted from the second light source 3.
[0043] FIG. 2 is a longitudinal sectional view illustrating the configuration of the lamp unit 100 according to the reference example. In the configuration shown in FIG. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.
[0044] As illustrated in FIG. 2, the light guide 5 of the lamp unit 100 according to the reference example is not provided with the light control surface 59. In this case, the lights L3 and L5 from the second light source 3 are totally reflected by the second reflecting surface 55 and pass through the inside of the light guide 5 and head toward the projection lens 4. The light L5 is reflected downward by the lower surface 57L of the cut-off element 57. Therefore, the lights L3 and L5 pass through a region S that is a region below the cutoff line forming portion 52 in the light guide 5 and has a wide width in the vertical direction. When guiding the lights L3 and L5 passing through such a wide region S1 in the vertical direction to the projection lens 4, in order to provide the second exit surface 58 with a wide width in the vertical direction, it is necessary to enlarge the light guide 5 below the cutoff line forming portion 52.
[0045] However, the light guide 5 of this embodiment illustrated in Figure 1 is provided with a light control surface 59 located below the cutoff line forming section 52, which controls the light L3 and L4 totally reflected by the second reflective surface 55 to be focused and directed toward the projection lens 4. Therefore, the light L3 and L4 totally reflected by the second reflective surface 55 can be efficiently guided to the projection lens 4 by passing through a narrow region of the light guide 5, and the second emission surface 58 can be made smaller in the vertical direction. Consequently, the light guide 5 below the cutoff line forming section 52 can be made smaller, and the amount of material used for the light guide 5 can be reduced.
[0046] The focal point F2 of the light control surface 59 may be located between the light guide 5 and the projection lens 4. The light control surface 59 controls the light L3 and L4, which have been totally reflected by the second reflective surface 55, to be focused at the focal point F2 of the light control surface 59. The focal point F2 of the light control surface 59 is located in front of the second emission surface 58.
[0047] In the example luminaire unit 100, the light guide 5 is not provided with a light control surface 59. As a result, some of the light totally reflected by the second reflective surface 55 does not reach the projection lens 4 and is lost, or even if it reaches the projection lens 4, it becomes stray light and does not contribute to the formation of the light distribution pattern, thus reducing the luminous flux utilization rate. Furthermore, as illustrated in Figure 2, the light L5 totally reflected by the second reflective surface 55 is totally reflected downward at the lower surface 57D, which is the interface between the cavity (air) of the notched element 57 and other parts (resin) in the cutoff line forming section 52. To guide the light L5 totally reflected downward at the lower surface 57D of the notched element 57 to the projection lens 4, it is necessary to provide a second emission surface 58 that is wide in the vertical direction.
[0048] However, in the present embodiment, as illustrated in FIG. 1, the light control surface 59 controls the light L3 and L4 that are totally reflected by the second reflection surface 55 so as to converge at the focal point F2 between the light guide 5 and the projection lens 4. Since the light L3 and L4 that are totally reflected by the second reflection surface 55 are efficiently guided to the projection lens 4, loss and stray light are reduced, and the light beam utilization rate can be increased. In particular, since the focal point F2 of the light control surface 59 is between the light guide 5 and the projection lens 4, it is possible to prevent the light L3 and L4 that are totally reflected by the second reflection surface 55 from heading downward when hitting the cutoff line forming portion 52. Since the light control surface 59 can reduce the light heading downward, it is easy to miniaturize the light guide 5 below the cutoff line forming portion 52, and the amount of material used for the light guide 5 can be reduced.
[0049] In the present embodiment, a notch 5C extending upward is formed at the lower part of the light guide 5, and the light control surface 59 may be constituted by the surface forming the notch 5C. The amount of material used for the light guide 5 can be reduced by the amount of the notch 5C. In addition, by providing the function of the light control surface 59 on the surface forming the notch 5C, the light L3 and L4 that are totally reflected by the second reflection surface 55 can be efficiently guided to the projection lens 4. Thus, the notch 5C simultaneously realizes a further reduction in the amount of material used for the light guide 5 and the control of the light L3 and L4.
[0050] The notch 5C is formed by a vertical surface 591 extending upward from the lower part 5D of the light guide 5 and an inclined surface 592 extending obliquely rearward from the upper end 59U of the vertical surface 591. The vertical surface 591 is not limited to a flat surface and may be a curved surface. The inclined surface 592 is not limited to a flat surface and may be a curved surface. Depending on the notch angle θ formed by the vertical surface 591 and the inclined surface 592 of the notch 5C, the light L3 and L4 that are totally reflected by the second reflection surface 55 are easily guided to the projection lens 4, facilitating optical design.
[0051] The cutoff line forming section 52 has a lower surface 57D, and the light guide 5 has a lower light guide section 50D located below the lower surface 57D, through which light L3 and L4 from the second reflective surface 55 passes. The light control surface 59 controls the light L3 and L4 totally reflected by the second reflective surface 55 to be directed diagonally upward towards the front. The lower surface 50DD of the lower light guide section 50D (the lower part 5D of the light guide 5) is inclined diagonally upward towards the front. Since the light L3 and L4 from the second reflective surface 55 are directed diagonally upward towards the front by the light control surface 59, even if the lower surface 50DD of the lower light guide section 50D is configured to be inclined diagonally upward towards the front, it does not obstruct the light from the second light source 3. For this reason, the amount of material used for the light guide 5 can be reduced compared to when the lower surface 50DD of the lower light guide section 50D is not inclined.
[0052] Although embodiments of the present invention have been described above, it goes without saying that the technical scope of the present invention should not be interpreted as being limited by the description of these embodiments. These embodiments are merely examples, and it will be understood by those skilled in the art that various modifications to the embodiments are possible within the scope of the invention as described in the claims. The technical scope of the present invention should be determined based on the scope of the invention as described in the claims and the scope of its equivalents.
[0053] The configurations described in each of the items listed below also constitute part of this disclosure. Item 1: A lighting unit comprising: a first light source that emits light to form a low-beam light distribution pattern including a cutoff line and a high-beam light distribution pattern; a second light source that emits light to form the high-beam light distribution pattern; a projection lens that projects the light emitted from the first light source and the second light source forward; and a light guide that guides the light emitted from the first light source and the second light source to the projection lens, wherein the light guide has: a cutoff line forming section that totally reflects a portion of the light emitted from the first light source to form the cutoff line of the low-beam light distribution pattern; a second optical element that makes the light emitted from the second light source into parallel light; a second reflective surface that totally reflects the parallel light formed by the second optical element so that it passes below the cutoff line forming section and toward the projection lens; and a light control surface provided below the cutoff line forming section that controls the light totally reflected by the second reflective surface to focus toward the projection lens. Item 2: The luminaire unit according to Item 1, wherein the light control surface controls the light totally reflected by the second reflecting surface to focus at a focal point between the light guide and the projection lens. Item 3: The luminaire unit according to Item 1 or 2, wherein a notch extending upward is formed at the lower part of the light guide, and the light control surface is composed of the surface forming the notch. Item 4: The luminaire unit according to Item 3, wherein the notch is formed by a vertical surface extending upward from the lower part of the light guide and an inclined surface extending diagonally backward from the upper end of the vertical surface. Item 5: The luminaire unit according to any one of Items 1 to 4, wherein the cutoff line forming portion has a flat portion extending in the front-rear direction, the light guide has a lower light guide portion located below the flat portion through which light from the second reflecting surface passes, the light control surface controls the light totally reflected by the second reflecting surface to diagonally upward toward the front, and the lower surface of the lower light guide portion is inclined diagonally upward toward the front.
[0054] This application claims priority under Japanese application No. 2024-228547, filed on 25 December 2024, and incorporates all the provisions contained in the said Japanese application.
Claims
1. A luminaire unit comprising: a first light source that emits light to form a low-beam light distribution pattern including a cutoff line and a high-beam light distribution pattern; a second light source that emits light to form the high-beam light distribution pattern; a projection lens that projects the light emitted from the first light source and the second light source forward; and a light guide that guides the light emitted from the first light source and the second light source to the projection lens, wherein the light guide has: a cutoff line forming section that totally reflects a portion of the light emitted from the first light source to form the cutoff line of the low-beam light distribution pattern; a second optical element that converts the light emitted from the second light source into parallel light; a second reflective surface that totally reflects the parallel light formed by the second optical element so that it passes below the cutoff line forming section and is directed toward the projection lens; and a light control surface provided below the cutoff line forming section that concentrates the light totally reflected by the second reflective surface and controls it to be directed toward the projection lens.
2. The light control surface controls the light totally reflected by the second reflecting surface to focus at the focal point between the light guide and the projection lens, as described in claim 1.
3. The luminaire unit according to claim 1, wherein a notch extending upward is formed in the lower part of the light guide, and the light control surface is composed of the surface forming the notch.
4. The luminaire unit according to claim 3, wherein the notch is formed by a vertical surface extending upward from the lower part of the light guide and an inclined surface extending diagonally backward from the upper end of the vertical surface.
5. The lamp unit according to claim 1, wherein the cutoff line forming portion has a flat portion extending in the front-rear direction, the light guide has a lower light guide portion located below the flat portion through which light from the second reflective surface passes, the light control surface controls the light totally reflected by the second reflective surface to be directed diagonally upward toward the front, and the lower surface of the lower light guide portion is inclined diagonally upward toward the front.