Vehicular lighting fixture

Abstract

To provide a vehicular lighting fixture that can restrain light distribution unevenness from occurring in a low-beam light distribution pattern, and prevents a high-beam partial light distribution pattern from expanding in a horizontal direction.SOLUTION: A vehicular lighting fixture comprises a projection lens 60, an upper separator 51 arranged behind the projection lens and above an optical axis AX60 of the projection lens, a lower separator 52 arranged behind the projection lens and below the optical axis of the projection lens, a low-beam light source 31A, and a high-beam light source 31B. The upper separator includes a low-beam light incidence part and a low-beam light emission surface. The lower separator includes a high-beam light incidence part and a high-beam light emission surface. The focus of the projection lens is located between the low-beam light emission surface and the high-beam light emission surface. The optical length of the upper separator is longer than the optical length of the lower separator.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle lighting device, and more particularly to a vehicle lighting device that can reduce the number of low-beam light sources while preventing the multiple partial light distribution patterns for high beams from spreading horizontally and satisfying the required luminous intensity for the partial light distribution patterns for high beams. [Background technology]

[0002] A vehicle lighting device has been proposed that includes a projection lens, a separator positioned behind the projection lens, and a substrate on which low-beam light sources and high-beam light sources are mounted, positioned behind the separator (see, for example, Patent Document 1).

[0003] In the vehicle lighting device described in Patent Document 1, the separator includes a low-beam light-receiving section located on the rear side of the vehicle and a low-beam light-emitting surface located on the front side of the vehicle, as well as a high-beam light-receiving section located on the rear side of the vehicle and a high-beam light-emitting surface located on the front side of the vehicle. The light emitted by the low-beam light source enters from the low-beam light-receiving section, exits from the low-beam light-emitting surface, and is projected by a projection lens (the focal point of the projection lens is located between the low-beam light-emitting surface and the high-beam light-emitting surface) to form a low-beam light distribution pattern. On the other hand, the light emitted by the high-beam light source enters from the high-beam light-receiving section, exits from the high-beam light-emitting surface, and is projected by a projection lens to form a high-beam light distribution pattern.

[0004] In response to this, the present inventors considered reducing the number of low-beam light sources in the vehicle lighting fixture described in Patent Document 1, from the viewpoint of cost reduction. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2019-220404 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the present inventors have found that in the vehicle lighting device described in Patent Document 1, reducing the number of low-beam light sources reduces the area in which the multiple partial light distribution patterns for low beams formed by the light from the multiple low-beam light sources overlap with each other, resulting in uneven light distribution in the low-beam light distribution pattern formed by the multiple partial light distribution patterns for low beams.

[0007] In response to this, the inventors investigated increasing the optical length of the separator to expand the partial light distribution pattern for the low beam horizontally, thereby increasing the area in which the partial light distribution patterns for the low beam overlap, and suppressing the occurrence of uneven light distribution in the low beam light distribution pattern.

[0008] However, increasing the optical length of the separator causes the partial light distribution pattern for the high beam, formed by light from multiple high beam light sources, to expand horizontally. As a result, the required luminous intensity for the partial light distribution pattern for the high beam becomes insufficient, making it impossible to implement the ADB function using that pattern.

[0009] The present invention was made to solve these problems, and aims to provide a vehicle lighting device that can suppress the occurrence of uneven light distribution in the low beam light distribution pattern even when the number of low beam light sources is reduced, and that does not cause the partial light distribution pattern for the high beam to spread horizontally (as a result, the required luminous intensity for the partial light distribution pattern for the high beam can be satisfied and the ADB function can be realized). [Means for solving the problem]

[0010] The vehicle light fixture according to the present invention comprises a projection lens, an upper separator positioned behind the projection lens and above the optical axis of the projection lens, a lower separator positioned behind the projection lens and below the optical axis of the projection lens, a low beam light source, and a high beam light source, wherein the upper separator includes a low beam light receiving section positioned on the rear side of the vehicle and a low beam light emitting surface positioned on the front side of the vehicle, and the lower separator includes a high beam light receiving section positioned on the rear side of the vehicle and a high beam light emitting surface positioned on the front side of the vehicle, and the low beam The light source emits light that enters from the low-beam light-inlet section, exits from the low-beam light-outlet surface, and is projected by the projection lens to form a low-beam light distribution pattern; the high-beam light source emits light that enters from the high-beam light-inlet section, exits from the high-beam light-outlet surface, and is projected by the projection lens to form a high-beam light distribution pattern; the focal point of the projection lens is located between the low-beam light-outlet surface and the high-beam light-outlet surface; and the optical length of the upper separator is longer than the optical length of the lower separator.

[0011] This configuration makes it possible to reduce the number of light sources for the low beams while suppressing unevenness in the low beam light distribution pattern, and to provide a vehicle lighting device in which the partial light distribution pattern for the high beams does not spread horizontally (as a result, the required luminous intensity for the partial light distribution pattern for the high beams can be satisfied, enabling the ADB function).

[0012] This is because the optical length of the upper separator is longer than the optical length of the lower separator. In other words, by making the optical length of the upper separator longer than that of the lower separator, the partial light distribution pattern for the low beam can be expanded horizontally, increasing the area of ​​overlap between them. Therefore, even if the number of low beam light sources is reduced, unevenness in the light distribution pattern for the low beam can be suppressed. Furthermore, since the optical length of the upper separator can be increased without increasing the optical length of the lower separator, even if the optical length of the upper separator is made longer than that of the lower separator as described above, the partial light distribution pattern for the high beam will not expand horizontally. As a result, even if the number of low beam light sources is reduced, the required luminous intensity for the partial light distribution pattern for the high beam can be satisfied, and the ADB function can be realized.

[0013] The above-described vehicle lighting device further comprises a circuit board on which the low-beam light source and the high-beam light source are mounted, wherein the low-beam light receiving section is positioned on the rearward side of the vehicle from the high-beam light receiving section, and the circuit board may be positioned at an angle such that the low-beam light source and the low-beam light receiving section face each other, and the high-beam light source and the high-beam light receiving section face each other.

[0014] Furthermore, in the above-mentioned vehicle light fixture, the low-beam light-receiving section includes a low-beam light-receiving surface and a low-beam total reflective surface positioned above the low-beam light-receiving surface, and the high-beam light-receiving section includes a high-beam light-receiving surface, a high-beam total reflective surface positioned above the high-beam light-receiving surface and a pair of side surfaces, and a cutoff shape corresponding to the cutoff line of the low-beam light distribution pattern may be provided between the low-beam light-emitting surface and the high-beam light-emitting surface.

[0015] Furthermore, in the above-mentioned vehicle lighting device, the low-beam total reflection surface is a total reflection surface that totally reflects the light from the low-beam light source that enters from the low-beam light-inlet and is incident on the low-beam total reflection surface, so as to concentrate the light near the focal point of the projection lens, and the high-beam total reflection surface is a total reflection surface that totally reflects the light from the high-beam light source that enters from the high-beam light-inlet and is incident on the high-beam total reflection surface, so as to concentrate the light near the focal point of the projection lens.

[0016] Furthermore, in the above-mentioned vehicle lighting device, the total reflective surface for the low beam is an elliptical total reflective surface with a first focal point located near the low beam light source and a second focal point located near the focal point of the projection lens, and the total reflective surface for the high beam may be a curved total reflective surface.

[0017] Furthermore, in the above-mentioned vehicle lighting device, in a horizontal cross-section, the central portion of the low-beam light-emitting surface and the central portion of the high-beam light-emitting surface are aligned with the focal plane of the projection lens, and the portions on both sides of the central portion of the low-beam light-emitting surface and the portions on both sides of the central portion of the high-beam light-emitting surface may be separated from the focal plane of the projection lens toward the rear of the vehicle.

[0018] Furthermore, in the above-mentioned vehicle lighting fixture, in a vertical cross-section, the low-beam light-emitting surface may extend upward via an inclined portion that slopes toward the front of the vehicle from the lower end of the low-beam light-emitting surface, and the high-beam light-emitting surface may extend downward via an inclined portion that slopes toward the front of the vehicle from the upper end of the high-beam light-emitting surface.

[0019] Furthermore, the above-mentioned vehicle lighting device may further include a light-shielding member disposed between the upper separator and the lower separator. [Effects of the Invention]

[0020] The present invention makes it possible to reduce the number of light sources for low beams while suppressing unevenness in the low beam light distribution pattern, and to provide a vehicle lighting device in which the partial light distribution pattern for high beams does not spread horizontally (as a result, the required luminous intensity for the partial light distribution pattern for high beams can be satisfied, and the ADB function can be realized). [Brief explanation of the drawing]

[0021] [Figure 1] This is a longitudinal cross-sectional view of the vehicle lighting fixture 10, cut along a vertical plane that includes the optical axis AX60 (reference axis) of the projection lens 60. [Figure 2] This is a perspective view of the circuit board 30. [Figure 3] This is a side view of the substrate 30 and the separator 50. [Figure 4] This is a top view of separator 50. [Figure 5] This is a front view of separator 50. [Figure 6] This is a perspective view of separator 50. [Figure 7] (a) A diagram (top view) showing the optical paths of Ray A4 emitted by the low-beam light source 31A4 and Ray A1 emitted by the low-beam light source 31A1, and (b) A diagram (side view) showing the optical path of Ray A4 emitted by the low-beam light source 31A4. [Figure 8] (a) An example of a partial light distribution pattern PLo4 for low beams formed by the light RayA4 emitted by the low beam light source 31A4, (b) An example of partial light distribution patterns PLo1 to PLo6 for low beams formed by the light emitted by the low beam light sources 31A1 to 31A6, and (c) An example of a low beam light distribution pattern PLO formed by the superposition of the partial light distribution patterns PLo1 to PLo6. [Figure 9] This is a bottom view of separator 50. [Figure 10] This is a magnified view of the vicinity of the light-receiving section 52a7 for the high beam. [Figure 11](a) A diagram (bottom view) showing the optical paths of Ray B7 emitted by the high beam light source 31B7 and Ray B2 emitted by the high beam light source 31B2, and (b) A diagram (side view) showing the optical path of Ray B7 emitted by the high beam light source 31B7. [Figure 12] (a) An example of a partial light distribution pattern PHi7 formed by the light RayB7 emitted by the high beam light source 31B7, (b) An example of a partial light distribution pattern PHi1 to PHi12 formed by the light emitted by the high beam light sources 31B1 to 31B12, and (c) An example of a high beam light distribution pattern PHi formed by the superposition of the partial light distribution patterns PHi1 to PHi12. [Figure 13] This is an enlarged view (modified example) of the vicinity of the light-receiving section 52a7 for the high beam. [Modes for carrying out the invention]

[0022] Hereinafter, a vehicle lighting device 10, which is one embodiment of the present invention, will be described with reference to the attached drawings. In each figure, corresponding components are denoted by the same reference numerals, and redundant explanations are omitted.

[0023] Figure 1 shows the optical axis AX of the projection lens 60 for the vehicle light fixture 10. 60 This is a longitudinal cross-sectional view taken along a vertical plane that includes the (reference axis).

[0024] The vehicle lighting fixture 10 of this embodiment is a vehicle headlight that functions as a low-beam or high-beam headlamp, and is mounted on both the left and right sides of the front end of a vehicle (not shown), such as an automobile. Since the vehicle lighting fixtures 10 mounted on both the left and right sides have a symmetrical configuration, the vehicle lighting fixture 10 mounted on the right side of the front end of the vehicle (right side when facing forward) will be described below as a representative example.

[0025] As shown in Figure 1, the vehicle lighting fixture 10 comprises a heat sink 20, a circuit board 30 on which low-beam light sources 31A and high-beam light sources 31B are mounted, a holder 40, a separator 50, and a projection lens 60. For the sake of explanation, the X, Y, and Z axes are defined below. The X axis extends in the longitudinal direction of the vehicle, the Y axis extends in the width direction of the vehicle, and the Z axis extends in the vertical direction.

[0026] The heat sink 20 includes a substrate fixing surface 20a to which the substrate 30 is fixed. The substrate fixing surface 20a is inclined at an angle θ1 with respect to the Z axis. The angle θ1 is, for example, 50°. As the material for the heat sink 20, metals with high thermal conductivity such as aluminum or copper, or alloys thereof, or alloys with low specific gravity such as magnesium are used. The heat sink 20 is manufactured by methods such as cutting, extrusion, insert, brazing, or die casting.

[0027] Figure 2 is a perspective view of the substrate 30.

[0028] The substrate 30 is a metal substrate such as aluminum, and includes low-beam light sources 31A1 to 31A6 and high-beam light sources 31B1 to 31B 12 This includes the light source mounting surface 30a on which the light source is mounted and the back surface 30b on the opposite side. Hereinafter, the light sources for low beam 31A1 to 31A6 and the light sources for high beam 31B1 to 31B 12 Unless otherwise specified, they are referred to as low-beam light source 31A and high-beam light source 31B.

[0029] The low-beam light source 31A and the high-beam light source 31B are semiconductor light-emitting elements such as LEDs. As shown in Figure 2, in this embodiment, six low-beam light sources 31A1 to 31A6 are mounted on the substrate 30 (light source mounting surface 30a) in an upper row, spaced apart from each other and arranged in a line along the Y-axis, and twelve high-beam light sources 31B1 to 31B are mounted on the lower row. 12 These are implemented with a spacing between them, arranged in a line along the Y-axis.

[0030] The low beam light source 31A and the high beam light source 31B have a light emitting surface. The light emitting surface is, for example, a rectangular light emitting surface with a side length of 1 mm. The low beam light source 31A and the high beam light source 31B are mounted on the substrate 30 (light source mounting surface 30a) in a state where the light emitting surface is parallel to the light source mounting surface 30a. The optical axis AX 31A (see FIGS. 1 and 3) of the low beam light source 31A extends through the center of the light emitting surface and in a direction perpendicular to the light emitting surface. Similarly, the optical axis AX 31B (see FIGS. 1 and 3) of the high beam light source 31B extends through the center of the light emitting surface and in a direction perpendicular to the light emitting surface.

[0031] The substrate 30 is fixed (e.g., screwed) to the heat sink 20 (substrate fixing surface 20a) in a state inclined at an angle θ1 with respect to the Z axis (see FIG. 1). Specifically, the substrate 30 is fixed to the heat sink 20 (substrate fixing surface 20a) in a state inclined at an angle θ1 with respect to the Z axis by the back surface 30b on the opposite side of the light source mounting surface 30a abutting against the substrate fixing surface 20a of the heat sink 20. Between the heat sink 20 (substrate fixing surface 20a) and the substrate 30 (back surface 30b), TIM (Thermal Interface Materials: thermal conductive members) such as thermal grease, thermal conductive sheet, thermal conductive adhesive, etc. are provided to enhance the adhesion between the two and reduce the contact thermal resistance.

[0032] FIG. 3 is a side view of the substrate 30 and the separator 50. FIG. 4 is a top view of the separator 50.

[0033] The separator 50 is made of silicone resin and includes an upper separator 51 and a lower separator 52 as shown in FIG. 3. Note that the separator 50 may be made of a heat-resistant material and is not limited to being made of silicone resin. For example, the separator 50 may be made of glass.

[0034] The upper separator 51 is disposed above the optical axis AX 60 of the projection lens 60. On the other hand, the lower separator 52 is disposed below the optical axis AX 60 of the projection lens 60. The optical axis AX 60It extends in the X-axis direction. Also, as shown in Figure 4, the separator 50 is aligned with the optical axis AX of the projection lens 60 when viewed from above. 60 It is constructed symmetrically with respect to it.

[0035] The upper separator 51 and the lower separator 52 are integrally molded with the lower end of the low-beam light-emitting surface 51b of the upper separator 51 and the upper end of the high-beam light-emitting surface 52b of the lower separator 52 connected (see Figure 3). The upper separator 51 and the lower separator 52 may be molded separately.

[0036] The separator 50 is positioned in front of the substrate 30 in a state where the low-beam light-receiving section 51a (low-beam light-receiving surface 51c) and the high-beam light-receiving section 52a (high-beam light-receiving surface 52c) face the low-beam light source 31A and the high-beam light source 31B (see Figure 3) by fixing the holder 40 that holds the separator 50 to the heat sink 20 (see Figure 1).

[0037] The holder 40 includes a light-shielding section 41 (see Figure 1). The light-shielding section 41 is positioned between the upper separator 51 and the lower separator 52 so that light from the low-beam light source 31A that enters the upper separator 51 does not leak out and enter the lower separator 52, and light from the high-beam light source 31B that enters the lower separator 52 does not leak out and enter the upper separator 51.

[0038] The projection lens 60 is an aspherical lens. The projection lens 60 is positioned in front of the separator 50 by fixing it to the heat sink 20 or the like while the projection lens 60 is positioned relative to the separator 50. The focal point F of the projection lens 60 60 (See Figures 3 and 5) This is located between the lower end of the low-beam light-emitting surface 51b of the upper separator 51 and the upper end of the high-beam light-emitting surface 52b of the lower separator 52 (cutoff shape 51g).

[0039] Figure 5 is a front view of the separator 50.

[0040] As shown in Figure 5, between the lower end of the low-beam light-emitting surface 51b of the upper separator 51 and the upper end of the high-beam light-emitting surface 52b of the lower separator 52, there is a low-beam light distribution pattern P Lo A cutoff shape 51g (Z-shaped step) corresponding to the cutoff line is provided. The optical length of the upper separator 51 (the optical distance that light from the low-beam light source 31A passes through the upper separator 51) is longer than the optical length of the lower separator 52 (the optical distance that light from the high-beam light source 31B passes through the lower separator 52) (see Figure 3).

[0041] First, let's explain the upper separator 51.

[0042] Figure 6 is a perspective view of the separator 50.

[0043] The upper separator 51 includes a low-beam light-receiving section 51a (51a1 to 51a7; see Figures 3, 4, and 6) located on the rear side of the vehicle, and a low-beam light-emitting surface 51b (see Figure 3) located on the front side of the vehicle. Hereafter, unless otherwise distinguished, the low-beam light-receiving sections 51a1 to 51a7 will be referred to as the low-beam light-receiving section 51a.

[0044] The low-beam light-receiving sections 51a1 to 51a7 are arranged in a single line along the Y-axis. In the vehicle lighting device 10 mounted on the right side of the front end of the vehicle (right side when facing forward), as in this embodiment, the low-beam light sources 31A1 to 31A6 are arranged so that the low-beam light-receiving sections 51a1 to 51a6 face each other, as shown in Figure 4. The dotted rectangle in Figure 4 represents the low-beam light sources 31A1 to 31A6 that are visible through the upper separator 51 (low-beam light-receiving sections 51a1 to 51a6).

[0045] On the other hand, although not shown in the diagram, in the vehicle lighting device 10 mounted on the left side of the front end of the vehicle (left side when facing forward), the low beam light sources 31A1 to 31A6 are arranged with the low beam light receiving sections 51a2 to 51a7 facing each other, rather than the low beam light receiving sections 51a1 to 51a6.

[0046] In this way, the number of low-beam light-receiving sections 51a1 to 51a7 is greater than the number of low-beam light sources 31A1 to 31A6, and the optical axis AX of the projection lens 60 of the separator 50 is viewed from above. 60 By configuring it symmetrically (see Figure 4), the separator 50 (upper separator 51) can be used for both the vehicle lighting fixture 10 mounted on the right side of the front end of the vehicle (right side when facing forward) and the vehicle lighting fixture 10 mounted on the left side of the front end of the vehicle (left side when facing forward).

[0047] As shown in Figure 3, the low-beam light-receiving section 51a includes a low-beam light-receiving surface 51c facing the low-beam light source 31A (light-emitting surface), and a low-beam total reflection surface 51d positioned above the low-beam light-receiving surface 51c.

[0048] The low-beam light-receiving surface 51c is, for example, a plane parallel to the light-emitting surface of the low-beam light source 31A. The distance between the low-beam light source 31A (light-emitting surface) and the low-beam light-receiving surface 51c is about 2 mm, and the low-beam light source 31A is positioned close to the low-beam light-receiving surface 51c.

[0049] The total reflection surface 51d for the low beam is at the focal point F of the projection lens 60. 60 The low-beam total reflection surface 51d is a total reflection surface that reflects light from the low-beam light source 31A, which enters from the low-beam light-entering surface 51c and is incident on the low-beam total reflection surface 51d, so as to concentrate the light in the vicinity. In this embodiment, the low-beam total reflection surface 51d is the first focal point F1 51d (See Figure 3) is located near the low-beam light source 31A, and the second focal spot F2 51d (See Figure 3) This is the focal point F of the projection lens 60. 60 It is a pelvic-based total reflection surface located in the vicinity.

[0050] As shown in Figure 4, in a top view (and similarly in a horizontal cross-section), the central portion 51b1 of the low-beam light-emitting surface 51b aligns with the focal plane FP of the projection lens 60. On the other hand, the portions 51b2 and 51b3 on either side of the central portion 51b1 of the low-beam light-emitting surface 51b are set back from the focal plane FP of the projection lens 60 toward the rear of the vehicle. As a result, as shown in Figure 7(a), the angle of incidence of light incident on the portions 51b2 and 51b3 on either side of the central portion 51b1 of the low-beam light-emitting surface 51b (see, for example, Ray A1 in Figure 7(a)) becomes smaller. This suppresses Fresnel reflection (Fresnel loss) or total internal reflection in the portions 51b2 and 51b3 on either side of the central portion 51b1 of the low-beam light-emitting surface 51b, allowing for efficient extraction of light from the portions 51b2 and 51b3 on either side of the central portion 51b1 of the low-beam light-emitting surface 51b. Figure 7(a) is a diagram (top view) showing the optical paths of Ray A4 emitted from the low-beam light source 31A4 and Ray A1 emitted from the low-beam light source 31A1.

[0051] As shown in Figure 3, in a side view (and similarly in a vertical cross-section), the low-beam light-emitting surface 51b extends upward from its lower end via an inclined portion 51g that slopes toward the front of the vehicle. As a result, as shown in Figure 7(b), the angle of incidence of light incident on the low-beam light-emitting surface 51b near its lower end (inclined portion 51g) (for example, see Ray A4 in Figure 7(b)) becomes smaller. This suppresses Fresnel reflection (Fresnel loss) or total internal reflection occurring near the lower end (inclined portion 51g) of the low-beam light-emitting surface 51b, allowing for efficient light extraction even in the vicinity of the lower end (inclined portion 51g) of the low-beam light-emitting surface 51b. Figure 7(b) is a diagram (side view) showing the optical path of Ray A4 emitted by the low-beam light source 31A4. The low-beam light-emitting surface 51b is at the focal point F of the projection lens 60. 60 It is preferable to position it slightly further towards the rear of the vehicle. This prevents dust and other debris adhering to the vicinity of the cutoff shape 51g from being projected onto the low beam light distribution pattern.

[0052] As shown in Figure 3, a lower surface 51e is provided between the lower end of the low-beam light-emitting surface 51b and the low-beam light-receiving surface 51c. Furthermore, an upper surface 51f is provided between the upper end of the low-beam light-emitting surface 51b and the low-beam total reflection surface 51d.

[0053] Figure 8(a) shows the partial light distribution pattern P for the low beam, formed by the light RayA4 emitted by the low beam light source 31A4. Lo4 This is one example. Note that the partial light distribution pattern P in Figure 8(a) Lo4 The outline is an isoluminescence line (representing 625 cd). Figure 8(b) shows the partial light distribution pattern P for the low beam formed by the light emitted by the low beam light sources 31A1 to 31A6. Lo1 ~P Lo6 This is one example. In reality, partial light distribution pattern P Lo1 ~P Lo6 The upper and lower edges of the light distribution pattern P are roughly aligned, but since it would be difficult to see if they were drawn in that aligned state, a partial light distribution pattern P is shown in Figure 8(b). Lo1 ~P Lo6 The diagram is drawn with the elements shifted vertically. Figure 8(c) shows the partial light distribution pattern P. Lo1 ~P Lo6 Low beam light distribution pattern P is formed by the superposition of these elements. LO This illustrates one example. Note that the light distribution patterns shown in Figures 8(a) to 8(c) are formed on a virtual vertical screen (located approximately 25m in front of the vehicle's front) that is directly facing the front of the vehicle.

[0054] The low beam light distribution pattern P shown in Figure 8(c) LO It is formed as follows:

[0055] First, the low-beam light sources 31A1 to 31A6 are turned on. For example, the light RayA4 emitted by the low-beam light source 31A4 (see Figures 7(a) and 7(b)) enters the low-beam light-incoming surface 51c opposite the low-beam light source 31A4, is totally reflected by the low-beam total reflection surface 51d, and is emitted from the low-beam light-out surface 51b. This results in the partial light distribution pattern P shown in Figure 8(a). Lo4A corresponding luminosity distribution is formed near the focal plane FP of the projection lens 60.

[0056] This partial light distribution pattern P Lo4 The corresponding luminous intensity distribution is projected forward by the projection lens 60, resulting in a partial light distribution pattern P as shown in Figure 8(a). Lo4 A formation is created.

[0057] Similarly, the light emitted by the low-beam light sources 31A1-31A3, 31A5, and 31A6, other than the low-beam light source 31A4, also enters through the low-beam light-incoming surface 51c opposite each of the low-beam light sources 31A1-31A3, 31A5, and 31A6, is totally reflected by the low-beam total reflection surface 51d, and is emitted from the low-beam light-out surface 51b. This results in the partial light distribution pattern P shown in Figure 8(b). Lo1 ~P Lo6 A corresponding luminosity distribution is formed near the focal plane FP of the projection lens 60.

[0058] As described above, a partial light distribution pattern P is formed near the focal plane FP of the projection lens 60. Lo1 ~P Lo6 The luminous intensity distribution corresponding to (see Figure 8(b)) is projected forward by the projection lens 60, resulting in the low beam light distribution pattern P as shown in Figure 8(c). Lo A light distribution pattern P for low beam is formed. Lo The upper edge includes a cutoff line corresponding to a cutoff shape 51g (see Figure 5) provided between the lower end of the low-beam light-emitting surface 51b of the upper separator 51 and the upper end of the high-beam light-emitting surface 52b of the lower separator 52.

[0059] Partial light distribution pattern for low beam (for example, P shown in Figure 8(a)) Lo4 (See reference) is a partial light distribution pattern for high beams, as described later (for example, P shown in Figure 12(a)). Hi7Compared to the above, it has a wider horizontal beam pattern, making it suitable for low-beam light distribution. This is because the optical length of the upper separator 51 (the optical distance that light from the low-beam light source 31A passes through the upper separator 51) is longer than the optical length of the lower separator 52 (the optical distance that light from the high-beam light source 31B passes through the lower separator 52) (see Figure 3).

[0060] Also, a partial light distribution pattern P for low beams. Lo1 ~P Lo6 Since these are formed in a state where they overlap each other in the horizontal direction (see Figure 8(b)), a low-beam light distribution pattern P spreads evenly in the horizontal direction with fewer low-beam light sources 31A. Lo It is possible to form this.

[0061] Next, we will explain the lower separator 52.

[0062] The lower separator 52 is a high beam light receiving section 52a (52a1~52a) located on the rear side of the vehicle. 13 (See Figures 3 and 6), including a high-beam light-emitting surface 52b located on the front side of the vehicle. Hereinafter, the high-beam light-receiving sections 52a1 to 52a 13 Unless otherwise specified, it will be referred to as the light-receiving section 52a for high beams.

[0063] As shown in Figure 6, the rear portion of the lower separator 52 is divided by a series of dividing grooves 52j that penetrate in the Z-axis direction, thereby creating strip-shaped high-beam light-receiving sections 52a1 to 52a 13 It constitutes [the structure].

[0064] Figure 9 is a bottom view of the separator 50.

[0065] High beam light receiving section 52a1~52a 13 These are arranged in a line along the Y-axis. In the vehicle lighting device 10 mounted on the right side of the front end of the vehicle (right side when facing forward), as in this embodiment, the high beam light sources 31B1 to 31B are arranged as shown in Figure 9. 12 The light receiving section 52a1~52a for high beam12 They are positioned facing each other.

[0066] On the other hand, although not shown in the diagram, the vehicle lighting device 10 mounted on the left side of the front end of the vehicle (left side when facing forward of the vehicle) has high beam light sources 31B1 to 31B 12 The light receiving section 52a1~52a for high beam 12 Instead, the light-receiving section 52a2~52a for high beams 13 They are positioned facing each other.

[0067] Thus, the light sources for high beams 31B1~31B 12 The number of light-receiving sections 52a1 to 52a for high beams 13 The number of these elements is increased, and the optical axis AX of the projection lens 60 is projected onto the separator 50 when viewed from above. 60 By configuring it symmetrically (see Figure 4), the separator 50 (lower separator 52) can be used for both the vehicle lighting fixture 10 mounted on the right side of the front end of the vehicle (right side when facing forward) and the vehicle lighting fixture 10 mounted on the left side of the front end of the vehicle (left side when facing forward).

[0068] As shown in Figure 3, the high-beam light-receiving section 52a includes a high-beam light-receiving surface 52c facing the high-beam light source 31B (light-emitting surface), and a high-beam total reflection surface 52d positioned above the high-beam light-receiving surface 52c. Furthermore, as shown in Figure 10, the high-beam light-receiving section 52a includes a pair of side surfaces 52g and 52h. Figure 10 is an enlarged view of the vicinity of the high-beam light-receiving section 52a7.

[0069] The light-receiving surface 52c for the high beam is, for example, a plane parallel to the light-emitting surface of the high beam light source 31B. The distance between the high beam light source 31B (light-emitting surface) and the light-receiving surface 52c for the high beam is about 2 mm, and the high beam light source 31B is positioned close to the light-receiving surface 52c for the high beam.

[0070] The total reflective surface 52d for the high beam is at the focal point F of the projection lens 60. 60The high-beam total reflection surface 52d is a total reflection surface that totally reflects light from the high-beam light source 31B that enters from the high-beam light-receiving surface 52c and is incident on the high-beam total reflection surface 52d, so as to concentrate the light in the vicinity. In this embodiment, the high-beam total reflection surface 52d is a curved reflection surface. The high-beam total reflection surface 52d has a first focal point located near the high-beam light source 31B, and a second focal point at the focal point F of the projection lens 60. 60 A nearby elliptical total reflection surface may also be used.

[0071] As shown in Figure 9, in a top view (and similarly in a horizontal cross-section), the central part 52b1 of the high-beam light-emitting surface 52b aligns with the focal plane FP of the projection lens 60. On the other hand, the parts 52b2 and 52b3 on either side of the central part 52b1 of the high-beam light-emitting surface 52b are set back from the focal plane FP of the projection lens 60 toward the rear of the vehicle. This reduces the angle of incidence of light incident on the parts 52b2 and 52b3 on either side of the central part 52b1 of the high-beam light-emitting surface 52b. As a result, Fresnel reflection (Fresnel loss) or total internal reflection is suppressed in the parts 51b2 and 51b3 on either side of the central part 52b1 of the high-beam light-emitting surface 52b, allowing light to be efficiently extracted from the parts 51b2 and 51b3 on either side of the central part 52b1 of the high-beam light-emitting surface 52b. Figure 11(a) is a diagram (bottom view) showing the optical paths of Ray B7, emitted by the high-beam light source 31B7, and Ray B2, emitted by the high-beam light source 31B2.

[0072] As shown in Figure 3, in a side view (and similarly in a vertical cross-section), the high-beam light-emitting surface 52b extends downward from its upper end via an inclined portion 52k that slopes toward the front of the vehicle. This reduces the angle of incidence of light (see, for example, Ray B7 in Figure 11(b)) incident on the high-beam light-emitting surface 52b near its upper end (inclined portion 52k). This suppresses Fresnel reflection (Fresnel loss) or total internal reflection in the high-beam light-emitting surface 52b near its upper end (inclined portion 52k), allowing for efficient light extraction even in that area. Figure 11(b) is a diagram (side view) showing the optical path of Ray B7 emitted by the high-beam light source 31B7. The high-beam light-emitting surface 52b is located at the focal point F of the projection lens 60. 60 It is preferable to position it slightly further towards the rear of the vehicle. This prevents dust and other debris adhering to the vicinity of the cutoff shape 51g from being projected onto the high beam light distribution pattern.

[0073] As shown in Figure 3, a lower surface 52e is provided between the lower end of the high beam light-emitting surface 52b and the high beam light-receiving surface 52c. Furthermore, an upper surface 52f is provided between the upper end of the high beam light-emitting surface 52b and the high beam total reflection surface 52d.

[0074] Figure 12(a) shows the partial light distribution pattern P formed by the light RayB7 emitted by the high-beam light source 31B7. Hi7 This is one example. Note that the partial light distribution pattern P in Figure 12(a) Hi7 The outline is an isoluminescence line (representing 625 cd). Figure 12(b) shows the high-beam light sources 31B1-31B. 12 Partial light distribution pattern P formed by the light emitted by [the object] Hi1 ~P Hi12 This is one example. In reality, partial light distribution pattern P Hi1 ~P Hi12 The lower edges generally coincide, but since it would be difficult to see if they were drawn in a coincidental state, the partial light distribution pattern P is shown in Figure 12(b). Hi1 ~P Hi12The diagram is drawn with an upward or downward shift. Figure 12(c) shows partial light distribution pattern P Hi1 ~P Hi12 High beam light distribution pattern P is formed by the superposition of these elements. Hi This illustrates one example. Note that the light distribution patterns shown in Figures 12(a) to 12(c) are formed on a virtual vertical screen (located approximately 25m in front of the vehicle) that is directly facing the front of the vehicle.

[0075] The high beam light distribution pattern P shown in Figure 12(c) Hi It is formed as follows:

[0076] First, the light sources for the high beams 31B1~31B 12 The lights are turned on. For example, the light RayB7 emitted by the high beam light source 31B7 (see Figures 11(a) and 11(b)) enters the high beam light-incoming surface 52c opposite the high beam light source 31B7, some of the light is totally reflected by the high beam total reflection surface 52d, some of the other light is totally reflected by a pair of side surfaces 52g and 52h (see Figure 10), and the light is emitted from the high beam light-out surface 52b. Note that some light is emitted directly from the high beam light-out surface 52b without being totally reflected by the high beam total reflection surface 52d, the pair of side surfaces 52g and 52h, etc. This results in the partial light distribution pattern P shown in Figure 12(a). Hi7 A corresponding luminosity distribution is formed near the focal plane FP of the projection lens 60.

[0077] This partial light distribution pattern P Hi7 The corresponding luminous intensity distribution is projected forward by the projection lens 60, resulting in a partial light distribution pattern P as shown in Figure 12(a). Hi7 A formation is created.

[0078] Similarly, high beam light sources 31B1-31B6, 31B8-31B, and 31B7, other than the high beam light source 31B7. 12 The light emitted is also from each of the high beam light sources 31B1~31B6, 31B8~31B 12Light enters from the opposing high-beam light-receiving surface 52c, some of the light is totally reflected by the high-beam total reflection surface 52d, and some of the other light is totally reflected by the pair of side surfaces 52g and 52h (see Figure 10), and then emitted from the high-beam light-emitting surface 52b. Note that some light is emitted directly from the high-beam light-emitting surface 52b without being totally reflected by the high-beam total reflection surface 52d, the pair of side surfaces 52g and 52h, etc. This results in the partial light distribution pattern P shown in Figure 12(b). Hi1 ~P Hi12 A corresponding luminosity distribution is formed near the focal plane FP of the projection lens 60.

[0079] This partial light distribution pattern P Hi1 ~P Hi12 The luminous intensity distribution corresponding to (see Figure 12(b)) is projected forward by the projection lens 60, resulting in the high-beam light distribution pattern P as shown in Figure 12(c). Hi A light distribution pattern P for high beams is formed. Hi The lower edge includes a cutoff line corresponding to a cutoff shape 51g (see Figure 5) provided between the lower end of the low-beam light-emitting surface 51b of the upper separator 51 and the upper end of the high-beam light-emitting surface 52b of the lower separator 52.

[0080] Partial light distribution pattern for high beams (for example, P shown in Figure 12(a)) Hi7 (See reference) The above-mentioned partial light distribution pattern for low beam (for example, P shown in Figure 8(a)) Lo4 Compared to the above, it is narrower horizontally and is suitable for the light distribution pattern of ADB (adaptive driving beam system; variable light distribution headlamp). This is because the optical length of the upper separator 51 (the optical distance that light from the low beam light source 31A passes through the upper separator 51) is longer than the optical length of the lower separator 52 (the optical distance that light from the high beam light source 31B passes through the lower separator 52) (see Figure 3).

[0081] Also, a partial light distribution pattern P for high beams. Hi1 ~P Hi12 (See Figure 12(b)) is a partial light distribution pattern P for the low beam.Lo1 ~P Lo6 It becomes brighter (see Fig. 8(b)). This is because the lower separator 52 includes strip-shaped light-incident portions 52a for high beams (a pair of side surfaces 52g and 52h) that control the light so as not to diffuse horizontally.

[0082] As described above, according to the present embodiment, even if the number of low-beam light sources is reduced, it is possible to suppress the occurrence of uneven light distribution in the low-beam light distribution pattern, and the partial light distribution pattern for high beams does not spread horizontally (as a result, the required luminous intensity of the partial light distribution pattern for high beams can be satisfied and the ADB function can be realized), and a vehicle lamp can be provided. This is because the optical length of the upper separator 51 is longer than the optical length of the lower separator 52. That is, according to the present embodiment, by making the optical length of the upper separator 51 longer than the optical length of the lower separator 52, the partial light distribution pattern P Lo1 ~P Lo6 for the low beam can be expanded horizontally to increase the overlapping area, so that even if the number of low-beam light sources is reduced, the occurrence of uneven light distribution in the low-beam light distribution pattern can be suppressed. Further, according to the present embodiment, the optical length of the upper separator 51 can be increased without increasing the optical length of the lower separator 52. Therefore, even if the optical length of the upper separator 51 is made longer than the optical length of the lower separator 52 as described above, the partial light distribution pattern P Hi1 ~P Hi12 for the high beam does not spread horizontally. As a result, even if the number of low-beam light sources is reduced, the required luminous intensity of the partial light distribution pattern for high beams can be satisfied and the ADB function can be realized.

[0083] Furthermore, according to this embodiment, the reflection angle of light from the low-beam light source 31A, which is totally reflected by the low-beam total reflection surface 51d, is sharper than the reflection angle of light from the high-beam light source 31B, which is totally reflected by the high-beam total reflection surface 52d. Also, the amount of light totally reflected is greater from the low-beam total reflection surface 51d. Therefore, the optical length of the upper separator 51 (the optical distance that light from the low-beam light source 31A passes through the upper separator 51) can be made even longer.

[0084] Furthermore, according to this embodiment, by making the optical length of the upper separator 51 (the optical distance that light from the low-beam light source 31A passes through the upper separator 51) longer than the optical length of the lower separator 52 (the optical distance that light from the high-beam light source 31B passes through the lower separator 52), the low-beam light source 31A and the high-beam light source 31B can be positioned further apart than in the above-mentioned Patent Document 1, thus providing a thermal advantage compared to the above-mentioned Patent Document 1.

[0085] Next, I will explain some variations.

[0086] The separator 50 may be molded with the low-beam light-receiving section 51a and the high-beam light-receiving section 52a from a heat-resistant material, and the remaining parts from a non-heat-resistant material (for example, acrylic or polycarbonate).

[0087] In the above embodiment, the substrate 30 was described as being fixed (for example, by screws) to the heat sink 20 (substrate fixing surface 20a) at an angle θ1 (=50°) with respect to the Z axis, but the angle θ1 is not limited to 50°. For example, the angle θ1 may be less than 50°. In this case, the number of low-beam light sources 31A can be increased. For example, if the angle θ1 is 40°, seven low-beam light sources 31A can be used. Also, the angle θ1 may be greater than 50°. In this way, the number of low-beam light sources 31A can be further reduced.

[0088] Furthermore, although the above embodiment describes an example in which the light-receiving surface 51c for the low beam and the light-receiving surface 52c for the high beam are planar (or substantially planar), the embodiment is not limited to this. For example, to provide greater directionality, the light-receiving surface 51c for the low beam (and the light-receiving surface 52c for the high beam) may be a convex surface (or a concave surface) that is convex toward the low beam light source 31A (or high beam light source 31B).

[0089] Figure 13 is an enlarged view (modified version) of the vicinity of the light-receiving section 52a7 for the high beam.

[0090] As shown in Figure 13, the light from the high-beam light source 31B, which is totally reflected by a pair of sides 52g and 52h, is along the optical axis AX 60 The high beam light-receiving sections 52a (for example, high beam light-receiving sections 52a6, 52a8) located on either side of the centrally located high beam light-receiving section 52a7 may be arranged in an inclined position so as to face the light towards the center. In this way, Fresnel reflection (Fresnel loss) or total internal reflection can be suppressed at the high beam light-emitting surface 52b.

[0091] The numerical values ​​shown in the above embodiments are all examples, and it goes without saying that other appropriate numerical values ​​can be used.

[0092] The embodiments described above are merely illustrative in all respects. The invention is not to be construed as limiting by the description of the embodiments above. The invention can be carried out in various other ways without departing from its spirit or main features. [Explanation of symbols]

[0093] 10...Vehicle lighting fixture, 20...Heat sink, 20a...Substrate fixing surface, 30...Substrate, 30a...Light source mounting surface, 30b...Back surface, 31A (31A1~31A6)...Light source for low beam, 31B (31B1~31B 12)…High beam light source, 40…Holder, 41…Light shielding part, 50…Separator, 51…Upper separator, 51a(51a1~51a7)…Low beam light incident part, 51c…Low beam light incident surface, 51d…Low beam total reflection surface, 51e…Bottom surface, 51f…Top surface, 51g…Cutoff shape, 52…Lower separator, 52a(52a1~52a 13 )…High beam light incident part, 52b…High beam light exit surface, 52c…High beam light incident surface, 52d…High beam total reflection surface, 52e…Bottom surface, 52f…Top surface, 52g, 52h…Pair of side surfaces, 52j…Division groove, 60…Projection lens, FP…Focal plane

Claims

1. A projection lens; an upper separator disposed behind the projection lens and above an optical axis of the projection lens; a lower separator disposed behind the projection lens and below an optical axis of the projection lens; A low beam light source; A high beam light source, the upper separator includes a low beam light entrance portion disposed on a rear side of the vehicle and a low beam light exit surface disposed on a front side of the vehicle, the lower separator includes a high beam light entrance portion disposed on a rear side of the vehicle and a high beam light exit surface disposed on a front side of the vehicle, the low beam light source emits light that enters through the low beam light entrance portion, exits through the low beam light exit surface, and is projected by the projection lens to form a low beam light distribution pattern; the high beam light source emits light that enters through the high beam light entrance portion, exits through the high beam light exit surface, and is projected by the projection lens to form a high beam light distribution pattern; a focal point of the projection lens is located between the low beam light output surface and the high beam light output surface; The optical length of the upper separator is longer than the optical length of the lower separator, The low beam light entrance portion includes a low beam light entrance surface and a low beam total reflection surface arranged above the low beam light entrance surface, The high beam light incident portion includes a high beam light incident surface, a high beam total reflection surface arranged above the high beam light incident surface, and a pair of side surfaces, a cutoff shape corresponding to a cutoff line of the low beam light distribution pattern is provided between the low beam light output surface and the high beam light output surface, the low beam total reflection surface is a total reflection surface that totally reflects light from the low beam light source that enters through the low beam light entrance portion and is incident on the low beam total reflection surface so as to be condensed near a focal point of the projection lens, The high beam total reflection surface is a vehicular lamp that totally reflects light from the high beam light source that enters through the high beam light entrance portion and is incident on the high beam total reflection surface so as to be concentrated near the focal point of the projection lens.

2. The low beam light source and the high beam light source are mounted on a substrate, The low beam light entrance portion is disposed rearward of the high beam light entrance portion, 2. The vehicle lamp according to claim 1, wherein the substrate is arranged in an inclined state so that the low beam light source faces the low beam light entrance portion, and the high beam light source faces the high beam light entrance portion.

3. the low beam total reflection surface is an elliptical total reflection surface having a first focal point located near the low beam light source and a second focal point located near a focal point of the projection lens, 3. The vehicle lamp according to claim 1, wherein the high beam total reflection surface is a curved total reflection surface.

4. In the horizontal section, 4. The vehicle lamp according to claim 1, wherein a central portion of the low beam light output surface and a central portion of the high beam light output surface are aligned along a focal plane of the projection lens, and both sides of the central portion of the low beam light output surface and both sides of the central portion of the high beam light output surface are separated from the focal plane of the projection lens toward the rear of the vehicle.

5. In the vertical section, The low beam light output surface extends upward via an inclined portion inclined from a lower end portion of the low beam light output surface toward the front of the vehicle, 5. The vehicular lamp according to claim 1, wherein the high beam output surface extends downward via an inclined portion that is inclined from an upper end portion of the high beam output surface toward a front of the vehicle.

6. The vehicular lamp according to claim 1 , further comprising a light blocking member disposed between the upper separator and the lower separator.

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