阅读说明：本技术 车辆用前照灯 (Vehicle headlamp ) 是由 藤田翔士 于 2020-04-25 设计创作，主要内容包括：具备：反射器(7),其具有在左右方向上排列的多个反射面(13)；n个光源(9),其朝向在左右方向上排列的反射面中的某一个反射面射出光；位于相邻位置的至少两个光源作为朝向同一反射面射出光的共有光源(14)而设置,由从n个光源分别射出的光形成照射在左右方向上不同区域的n个照射图案(20),以如下方式分别设定多个反射面的焦距,即n个照射图案在左右方向上依次设为第一照射图案到第n照射图案,紧接其后的编号的照射图案中的至少一半的区域与紧接其前的编号的照射图案中的至少一半的区域为在左右方向上重叠的状态,由从共有光源射出的光分别形成区域不重叠的相邻的照射图案。(The disclosed device is provided with: a reflector (7) having a plurality of reflecting surfaces (13) arranged in the left-right direction; n light sources (9) that emit light toward any one of the reflection surfaces arranged in the left-right direction; at least two light sources located at adjacent positions are provided as a common light source (14) for emitting light toward the same reflecting surface, n irradiation patterns (20) for irradiating different regions in the left-right direction are formed by the light emitted from the n light sources, the focal lengths of the plurality of reflecting surfaces are set such that the n irradiation patterns are sequentially set as a first irradiation pattern to an nth irradiation pattern in the left-right direction, at least one half region of the immediately subsequent irradiation pattern and at least one half region of the immediately preceding irradiation pattern overlap in the left-right direction, and adjacent irradiation patterns, the regions of which do not overlap, are formed by the light emitted from the common light source.)

1. A vehicle headlamp is provided with:

a reflector having a plurality of reflecting surfaces arranged in a left-right direction;

n light sources that emit light toward any one of the reflection surfaces arranged in the left-right direction;

at least two of the light sources located at adjacent positions are provided as a common light source for emitting light toward the same reflecting surface,

n irradiation patterns irradiating different regions in the left-right direction are formed by the lights emitted from the n light sources respectively,

the focal lengths of the plurality of reflection surfaces are respectively set as follows:

the n irradiation patterns are sequentially set to a first irradiation pattern to an nth irradiation pattern in a left-right direction,

at least half of the regions in the irradiation patterns of the number immediately after and at least half of the regions in the irradiation patterns of the number immediately before are in a state of overlapping in the left-right direction,

the adjacent irradiation patterns having non-overlapping regions are formed by the light emitted from the common light source.

2. The vehicle headlamp as defined in claim 1,

the focal length is set to 10mm to 15 mm.

3. The vehicular headlamp according to claim 1 or 2,

the common light source is constituted by two of the light sources.

4. The vehicular headlamp according to any one of claims 1 to 3, wherein,

a plurality of said common light sources are provided.

5. The vehicular headlamp according to any one of claims 1 to 4,

at least one of the light sources is provided as a non-shared light source other than the shared light source.

Technical Field

The present invention relates to a vehicle headlamp in which light emitted from a plurality of light sources for performing lighting control is reflected by a reflecting surface of a reflector.

Background

In a vehicle headlamp, each part such as a plurality of light sources and reflectors is disposed in a lamp chamber which is an internal space of a lamp housing constituted by a lamp housing and a cover, and lighting and turn-off control of the plurality of light sources is performed based on a traveling state of a vehicle (for example, see patent document 1).

The vehicle headlamp described in patent document 1 is configured to be capable of, for example, controlling so-called variable high Beam (ADB) that changes the light distribution pattern of high Beam by irradiating a region where another vehicle such as a preceding vehicle exists, which is detected by processing an image captured by a camera.

In the vehicle headlamp described in patent document 1, light is emitted from each of a plurality of semiconductor light emitting elements (LEDs) arranged side by side on the left and right and provided as light sources, different irradiation patterns are formed by the light emitted from each light source, and a light distribution pattern of the irradiation light to be irradiated forward is formed by these irradiation patterns.

By performing such control, it is possible to prevent glare from occurring in other vehicles such as a preceding vehicle.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2013-243080

Disclosure of Invention

Problems to be solved by the invention

However, in recent years, the shape of a vehicle body has been changed to various shapes due to the height design of a vehicle, and accordingly, there has been an increasing demand for a vehicle headlamp having a small size and a thin shape with a small vertical width.

Therefore, in order to achieve miniaturization, particularly miniaturization of the vertical width, in a vehicle headlamp using a reflector having the ADB function as described above, for example, it is conceivable to reduce the focal length of the reflecting surface of the reflector and reduce the curvature of the reflecting surface.

However, although the vehicle headlamp can be downsized by reducing the focal length of the reflection surface to form a reflector having a small vertical width, the position of the irradiation pattern of the light emitted from the light source is shifted in the left-right direction with the change of the focal length, and there is a possibility that luminance unevenness occurs in the light distribution pattern formed by these irradiation patterns.

Therefore, an object of the vehicle headlamp of the present invention is to reduce the size of the vehicle headlamp while suppressing the luminance unevenness in the light distribution pattern.

Means for solving the problems

First, a vehicle headlamp according to the present invention includes: a reflector having a plurality of reflecting surfaces arranged in a left-right direction; n light sources that emit light toward any one of the reflection surfaces arranged in the left-right direction; at least two of the light sources located adjacent to each other are provided as a common light source for emitting light toward the same reflecting surface, n irradiation patterns for irradiating different regions in the left-right direction are formed by light emitted from the n light sources, and focal lengths of the plurality of reflecting surfaces are set as follows: the n irradiation patterns are sequentially set from a first irradiation pattern to an nth irradiation pattern in a left-right direction, at least half of the irradiation patterns of the number immediately after the first irradiation pattern and at least half of the irradiation patterns of the number immediately before the first irradiation pattern overlap each other in the left-right direction, and the adjacent irradiation patterns, the areas of which do not overlap each other, are formed from the light emitted from the common light source.

Thus, in a state where at least half of the regions of the irradiation patterns respectively formed by the lights emitted from the respective light sources overlap each other in the left-right direction, the adjacent irradiation patterns whose regions do not overlap each other are formed by the lights emitted from the common light source.

Secondly, in the vehicle headlamp of the present invention, it is preferable that the focal length is 10mm to 15 mm.

Thereby, the curvature of the reflector becomes sufficiently small.

Third, in the vehicle headlamp of the present invention, it is preferable that the common light source is composed of two light sources.

This makes it possible to increase the number of reflecting surfaces without excessively increasing the size of each reflecting surface corresponding to each shared light source.

Fourth, in the vehicle headlamp of the present invention, it is preferable that a plurality of the common light sources are provided.

Thereby, the number of reflecting surfaces is greatly reduced with respect to the number of light sources.

Fifth, in the vehicle headlamp of the present invention, it is preferable that at least one of the light sources is provided as an unshared light source other than the shared light source.

This improves the degree of freedom in the arrangement of the plurality of light sources in relation to the plurality of reflection surfaces.

Effects of the invention

According to the present invention, in a state where at least half of the regions of the irradiation patterns formed by the lights emitted from the respective light sources overlap each other in the left-right direction, the adjacent irradiation patterns whose regions do not overlap each other are formed by the lights emitted from the common light source, and therefore, the focal length of the reflection surface in the reflector can be reduced while forming a light distribution pattern in which luminance unevenness is less likely to occur, and the vehicle headlamp can be downsized while suppressing the luminance unevenness in the light distribution pattern.

Drawings

Fig. 1 is a view showing an embodiment of a vehicle headlamp of the present invention together with fig. 2 to 8, and this view is a sectional view of the vehicle headlamp.

Fig. 2 is a schematic front view of the lamp unit.

Fig. 3 is a conceptual diagram illustrating an irradiation pattern.

Fig. 4 is a diagram showing a comparison between a difference in light sources forming each irradiation pattern and the like and a conventional vehicle headlamp.

Fig. 5 is a conceptual diagram illustrating an irradiation pattern of the lamp unit according to the first modification.

Fig. 6 is a diagram illustrating differences in light sources and the like for forming each irradiation pattern in the lamp unit of the first modification.

Fig. 7 is a conceptual diagram illustrating an irradiation pattern of a lamp unit according to a second modification.

Fig. 8 is a diagram illustrating differences in light sources and the like for forming each irradiation pattern in the lamp unit of the second modification.

Detailed Description

Hereinafter, a mode of a vehicle headlamp for implementing the present invention will be described with reference to the drawings.

The vehicle headlamp 1 is mounted and arranged on both left and right end portions of a front end portion of a vehicle body.

The vehicle headlamp 1 includes: a lamp housing 2 having an opening at a front end; and a cover 3 attached to the lamp housing 2 in a state where an opening of the lamp housing 2 is closed (see fig. 1). The lamp housing 2 and the cover 3 constitute a lamp housing 4. The inner space of the lamp housing 4 is formed as a lamp chamber 4 a.

A lamp unit 5 is disposed in the lamp chamber 4 a. The luminaire unit 5 has a support 6, a reflector 7, a base plate 8 and light sources 9, … ….

The bracket 6 has a plate-shaped coupling portion 10 facing in the front-rear direction and a plate-shaped attachment portion 11 facing in the up-down direction, and an upper end portion of the coupling portion 10 is continuous with a rear end portion of the attachment portion 11. The front half of the mounting portion 11 is provided as a reflector mounting portion 11a thicker than the rear half, and the rear half is provided as a substrate mounting portion 11 b. The lower surface of the reflector mounting portion 11a is located below the lower surface of the substrate mounting portion 11 b.

The reflector 7 includes a plate-shaped attached portion 12 facing in the vertical direction and a reflecting portion 13 formed in a curved surface shape that displaces in the forward direction as it goes downward, and a rear end portion of the attached portion 12 is continuous with an upper end portion of the reflecting portion 13. The mounted portion 12 is formed with a light-transmitting hole 12 a. The reflection unit 13 is divided into, for example, four parts in the left-right direction (see fig. 2). The inner surfaces of the four portions of the reflection portion 13 are formed as a first reflection surface 13a, a second reflection surface 13b, a third reflection surface 13c, and a fourth reflection surface 13d, respectively, in this order from the inside toward the outside in the lateral direction of the vehicle. The first reflection surface 13a, the second reflection surface 13b, the third reflection surface 13c, and the fourth reflection surface 13d are each formed as a paraboloid which is convex obliquely rearward and downward.

The focal lengths of the first reflection surface 13a, the second reflection surface 13b, the third reflection surface 13c, and the fourth reflection surface 13d of the reflector 7 are set to 10mm to 15mm, for example. The front half of the mounted portion 12 of the reflector 7 is mounted on the reflector mounting portion 11a of the bracket 6, and the reflector 7 is positioned on the front side of the coupling portion 10 (see fig. 1).

The substrate 8 is formed to be laterally long and is mounted on the lower surface of the substrate mounting portion 11b of the holder 6 (see fig. 2). The substrate 8 is connected to a control circuit not shown.

The light sources 9, … … are mounted on the lower surface of the substrate 8 so as to be separated from each other. The Light sources 9, … … are Light Emitting Diodes (LEDs), and are provided in 7 numbers, for example. Therefore, the number n of light sources 9 is 7. The light emitted from the light sources 9, and … … passes through the transmission hole 12a and travels toward the reflection portion 13 of the reflector 7, is reflected by the reflection portion 13, passes through the cover 3, and is emitted forward (see fig. 1).

The light sources 9, … … are a second light source 9B, a first light source 9A, a fourth light source 9D, a third light source 9C, a sixth light source 9F, a fifth light source 9E, and a seventh light source 9G (see fig. 2) in this order from the inside toward the outside in the lateral direction of the vehicle.

The second light source 9B and the first light source 9A are provided as a first shared light source 14A for emitting light toward the first reflection surface 13a, the fourth light source 9D and the third light source 9C are provided as a second shared light source 14B for emitting light toward the second reflection surface 13B, and the sixth light source 9F and the fifth light source 9E are provided as a third shared light source 14C for emitting light toward the third reflection surface 13C. The seventh light source 9G is provided as the unshared light source 15, and light emitted from the seventh light source 9G is directed toward the fourth reflection surface 13 d.

The lamp unit 5 configured as described above is movable in a horizontal direction and a vertical direction with respect to the lamp housing 4 via the optical axis adjustment mechanism 16 (see fig. 1).

The optical axis adjusting mechanism 16 includes alignment screws 17 and a pivot point portion not shown. The alignment screws 17, 17 extend in the front-rear direction, and have screw portions 17a, 17a at the front end portions thereof. The alignment screws 17, 17 are coupled to the coupling portion 10 of the bracket 6 via the nut members 18, 18 in a state where the screw-threaded portions 17a, 17a are respectively screwed to the nut members 18, and the rear end portions are respectively coupled to the lamp housing 2 so as to be rotatable in a state where they cannot move in the front-rear direction. The connection portion 10 of the bracket 6 is also connected to the lamp housing 2 via a pivot point portion, and is provided to be rotatable in an arbitrary direction with respect to the lamp housing 2 with the pivot point portion as a fulcrum.

In the vehicle headlamp 1, when one of the alignment screws 17 is rotated, the lamp unit 6 is tilted in a direction corresponding to the rotation direction thereof with the other alignment screw 17 and the pivot point portion as a fulcrum, and alignment adjustment of the lamp unit 6 is performed.

Further, the vehicle headlamp 1 may be provided with a so-called leveling adjustment mechanism that adjusts the direction of the optical axis inclined by the weight of the vehicle load.

The vehicle is provided with a camera, not shown, for capturing an image of the state of the irradiation region of the vehicle headlamp 1, and a detection unit, not shown, for detecting the state of the irradiation region based on image data captured by the camera. In the vehicle headlamp 1, the control circuit performs lighting and turn-off control of the light sources 9, and … … based on the detection result of the detection unit.

In this way, in the vehicle headlamp 1, the lighting-off control of the light sources 9, … … is performed based on the detection result of the detection unit, and thus, for example, a function called an Adaptive Driving Beam (ADB) for lighting-off the light source 9 that irradiates an area where another vehicle such as a preceding vehicle detected by processing an image captured by a camera exists and changing the light distribution pattern of the high Beam exerts an actual effect.

In the vehicle headlamp 1, different irradiation patterns 20, … … are formed by light emitted from the light sources 9, … …. The irradiation patterns 20, … … are formed as a first irradiation pattern 20A, a second irradiation pattern 20B, a third irradiation pattern 20C, a fourth irradiation pattern 20D, a fifth irradiation pattern 20E, a sixth irradiation pattern 20F, and a seventh irradiation pattern 20G, respectively, in this order. A light distribution pattern 21 (see fig. 3) of the vehicle headlamp 1 is formed by the first irradiation pattern 20A, the second irradiation pattern 20B, the third irradiation pattern 20C, the fourth irradiation pattern 20D, the fifth irradiation pattern 20E, the sixth irradiation pattern 20F, and the seventh irradiation pattern 20G. Therefore, the number of the irradiation patterns 20 is the same as the number of the light sources 9, and the number n of the irradiation patterns 20 is 7.

For simplicity, the first irradiation pattern 20A, the second irradiation pattern 20B, the third irradiation pattern 20C, the fourth irradiation pattern 20D, the fifth irradiation pattern 20E, the sixth irradiation pattern 20F, and the seventh irradiation pattern 20G will be described below as only the irradiation pattern 20A, the irradiation pattern 20B, the irradiation pattern 20C, the irradiation pattern 20D, the irradiation pattern 20F, and the irradiation pattern 20G, respectively.

The irradiation patterns 20A, 20B, and 20G are formed in order from the inside to the outside in the lateral direction of the vehicle, and irradiate different regions in the lateral direction. The irradiation patterns 20A, 20B, … …, and 20G are formed such that the half portions of the irradiation patterns 20 and 20 adjacent to each other in the left-right direction overlap each other. In fig. 3, the irradiation patterns 20A, 20C, 20E, and 20G and the irradiation patterns 20B, 20D, and 20F are illustrated in a state of being slightly shifted in the vertical direction in order to easily understand the regions of the irradiation patterns 20A, 20B, … …, and 20G.

The relationship between the positions where the irradiation patterns 20, … … are formed and the light emitted from the light sources 9, … … will be described below (see fig. 4).

In the following, in order to facilitate understanding of the structure of the vehicle headlamp 1, the structure of the vehicle headlamp 1 will be described while showing the structure of the conventional vehicle headlamp X having the ADB function. In fig. 4, the drawing shown in the uppermost stage schematically shows the positional relationship between the reflection surfaces 13a to 13d and the light sources 9, and … …, and in order to facilitate comparison between the vehicle headlamp 1 and the conventional vehicle headlamp X, the conventional vehicle headlamp X also shows an example in which the irradiation pattern is formed by the same configuration as that of the vehicle headlamp 1 shown in the uppermost stage of fig. 4.

In the graph comparing the vehicle headlamp X and the vehicle headlamp 1 of fig. 4, the upper diagram is a schematic diagram showing which light source each irradiation pattern is formed by, the middle diagram is a schematic diagram showing a relationship between each irradiation pattern and the light source forming each irradiation pattern, and the lower diagram is a schematic diagram showing a shape of the reflector.

In the vehicle headlamp X, the irradiation patterns sequentially arranged in the left-right direction are formed by light reflected by the reflecting surfaces sequentially arranged in the left-right direction.

Specifically, the irradiation patterns 20A and 20B are formed by light emitted from the first light source 9A and the second light source 9B and reflected by the first reflection surface 13a, the irradiation patterns 20C and 20D are formed by light emitted from the third light source 9C and the fourth light source 9D and reflected by the second reflection surface 13B, the irradiation patterns 20E and 20F are formed by light emitted from the fifth light source 9E and the sixth light source 9F and reflected by the third reflection surface 13C, and the irradiation pattern 20G is formed by light emitted from the seventh light source 9C and reflected by the fourth reflection surface 13D, respectively. In this case, the focal lengths of the first reflecting surface 13a, the second reflecting surface 13b, the third reflecting surface 13c, and the fourth reflecting surface 13d in the vehicle headlamp X are, for example, about 20 mm.

In the vehicle headlamp X as described above, since the ADB function is exhibited well and the irradiation patterns 20 and 20 adjacent to each other in the left-right direction are formed in a pattern in which the respective halves overlap, it is difficult for luminance unevenness to occur in light distribution.

However, in order to cope with the recent high design of the vehicle, it is desired to develop a vehicle headlamp having a small vertical width, and it is desired to miniaturize the reflector while maintaining the basic structure of the vehicle headlamp X. In order to miniaturize the reflector, it is considered that the focal length of the reflecting surface in the reflector is made smaller than the focal length of the reflecting surface in the vehicle headlamp X.

If the focal length of the reflecting surface is reduced, the curvature of the reflecting surface is increased, and the vertical width of the reflector is reduced, thereby realizing the miniaturization of the vehicle headlamp.

However, if the focal length of the reflection surface is reduced, the irradiation patterns formed by the light emitted from the light source are shifted in the left-right direction, and the manner of overlapping the irradiation patterns changes, which tends to cause luminance unevenness. For example, if the focal length of the reflection surface is made smaller by about several millimeters than the reflection surface of the reflection portion 13X in the vehicle headlamp X while maintaining the basic structure of the vehicle headlamp X, the irradiation pattern 20B formed by the light emitted from the light source 9B is shifted in a direction away from the irradiation pattern 20A, for example.

Therefore, in the lamp unit 5 of the vehicle headlamp 1, the focal lengths of the first reflecting surface 13a, the second reflecting surface 13b, the third reflecting surface 13c, and the fourth reflecting surface 13d are further reduced by about several millimeters with respect to the reflecting surface of the reflecting portion 13X in the vehicle headlamp X, and as described below in detail, at least half of the regions in the irradiation pattern of the immediately subsequent number and at least half of the regions in the irradiation pattern of the immediately preceding number overlap in the left-right direction, and adjacent irradiation patterns, the regions of which do not overlap, are formed from light emitted from the common light source. In the following, a case where half regions in the irradiation pattern overlap each other will be described as an example.

Specifically, as shown in the right-hand drawing in fig. 4, the irradiation patterns 20A and 20C are formed by light emitted from the first light source 9A and the second light source 9B and reflected by the first reflecting surface 13a, the irradiation patterns 20B and 20D are formed by light emitted from the third light source 9C and the fourth light source 9D and reflected by the second reflecting surface 13B, the irradiation patterns 20E and 20G are formed by light emitted from the fifth light source 9E and the sixth light source 9F and reflected by the third reflecting surface 13C, and the irradiation pattern 20F is formed by light emitted from the seventh light source 9C and reflected by the fourth reflecting surface 13D.

That is, adjacent irradiation patterns 20A, 20C are formed by light emitted from the first light source 9A and the second light source 9B constituting the first shared light source 14A, adjacent irradiation patterns 20B, 20D are formed by light emitted from the third light source 9C and the fourth light source 9D constituting the second shared light source 14B, and adjacent irradiation patterns 20E, 20F are formed by light emitted from the fifth light source 9E and the sixth light source 9F constituting the third shared light source 14C. The manner of overlapping the irradiation patterns 20, and … … is not changed from the vehicle headlamp X, and is set to a state in which the half area in the irradiation pattern 20B overlaps the half area in the irradiation pattern 20A, the half area in the irradiation pattern 20C overlaps the half area in the irradiation pattern 20B, the half area in the irradiation pattern 20D overlaps the half area in the irradiation pattern 20C, the half area in the irradiation pattern 20E overlaps the half area in the irradiation pattern 20D, the half area in the irradiation pattern 20F overlaps the half area in the irradiation pattern 20E, and the half area in the irradiation pattern 20G overlaps the half area in the irradiation pattern 20F.

In the vehicle headlamp 1, the focal lengths of the first reflecting surface 13a, the second reflecting surface 13b, the third reflecting surface 13c, and the fourth reflecting surface 13d are set to be, for example, 10mm to 15 mm.

As described above, even if the focal length of the reflection surface is reduced, the adjacent irradiation patterns are formed such that at least half of the regions in the immediately subsequent irradiation pattern and at least half of the regions in the immediately preceding irradiation pattern overlap in the left-right direction, and the regions do not overlap each other from the light emitted from the common light source, whereby luminance unevenness is less likely to occur in the light distribution of the vehicle headlamp 1.

As described above, in the vehicle headlamp 1, the focal lengths of the reflecting surfaces (13a to 13D) are set such that at least half of the regions in the immediately subsequent numbered irradiation patterns 20 and at least half of the regions in the immediately preceding numbered irradiation patterns 20 overlap in the left-right direction, and the adjacent irradiation patterns 20, 20(20A and 20C, 20B and 20D, 20E and 20G) whose regions do not overlap are formed by the light emitted from the common light sources (14A to 14C), respectively.

Therefore, in a state where at least half of the regions of the irradiation patterns 20 respectively formed by the light emitted from the light sources 9 overlap each other in the left-right direction, the adjacent irradiation patterns 20, 20 whose regions do not overlap are formed by the light emitted from the common light sources (14A to 14C). Thus, the focal length of the reflecting surfaces (13 a-13 d) can be reduced while forming the light distribution pattern 21 in which luminance unevenness is less likely to occur, and the vehicle headlamp 1 can be downsized while suppressing the luminance unevenness in the light distribution pattern 21.

Further, since the focal lengths of the first reflecting surface 13a, the second reflecting surface 13b, the third reflecting surface 13c, and the fourth reflecting surface 13d are set to be, for example, 10mm to 15mm, the curvature of the reflector 7 is sufficiently large, and the vehicle headlamp 1 can be downsized by sufficiently downsizing the reflector 7.

Further, since the first shared light source 14A, the second shared light source 14B, and the third shared light source 14C are each configured by two light sources 9, the number of reflecting surfaces 13 can be increased without excessively increasing the number of reflecting surfaces 13 corresponding to the respective shared light sources 14, and the degree of freedom of light distribution control can be improved while ensuring the downsizing of the vehicle headlamp 1.

Further, in the vehicle headlamp 1, since the plurality of shared light sources 14 are provided, the number of the reflecting surfaces 13 is greatly reduced with respect to the number of the light sources 9, and the vehicle headlamp 1 can be downsized in the right-left direction while enhancing the degree of freedom of light distribution control.

Further, since at least one light source 9(9G) is provided as the unshared light source 15 and the plurality of light sources 9 are configured by the shared light source 14 and the unshared light source 15, the degree of freedom of arrangement of the plurality of light sources 9 is improved in relation to the plurality of reflection surfaces 13, and the degree of freedom of design relating to light distribution can be improved.

A modification of the lamp unit 5 will be described below (see fig. 5 to 8).

First, a lamp unit 5A according to a first modification will be described (see fig. 5 and 6).

The reflector 7 of the lamp unit 5A has a first reflecting surface 13a, a second reflecting surface 13b, a third reflecting surface 13c, and a fourth reflecting surface 13d (see fig. 5). The focal lengths of the first reflection surface 13a, the second reflection surface 13b, the third reflection surface 13c, and the fourth reflection surface 13d of the reflector 7 are set to 10mm to 15mm, for example.

The light sources 9, … … are provided with, for example, 6. Therefore, the number n of light sources 9 is 6. The light sources 9, … … are a first light source 9A, a third light source 9C, a second light source 9B, a fifth light source 9E, a fourth light source 9D, and a sixth light source 9F in this order from the inside to the outside in the lateral direction of the vehicle.

The first light source 9A and the sixth light source 9F are provided as unshared light sources 15 and 15, respectively, and light emitted from the first light source 9A is directed toward the first reflection surface 13a, and light emitted from the sixth light source 9F is directed toward the fourth reflection surface 13 d. The third light source 9C and the second light source 9B are provided as a first shared light source 14D for emitting light toward the second reflecting surface 13B, and the fifth light source 9E and the fourth light source 9D are provided as a second shared light source 14E for emitting light toward the third reflecting surface 13C.

In the lamp unit 5A, at least half of the regions in the immediately subsequent numbered illumination patterns and at least half of the regions in the immediately preceding numbered illumination patterns are overlapped in the left-right direction, and adjacent illumination patterns in which the regions do not overlap are formed from the light emitted from the common light source, respectively (see fig. 6). In fig. 6, a case where half regions in the irradiation pattern overlap each other will be described as an example.

Specifically, the irradiation patterns 20A and 20C are formed by light emitted from the second light source 9B and the third light source 9C and reflected by the second reflection surface 13B, the irradiation pattern 20B is formed by light emitted from the light source 9A and reflected by the first reflection surface 13a, the irradiation patterns 20D and 20F are formed by light emitted from the fourth light source 9D and the fifth light source 9E and reflected by the third reflection surface 13C, and the irradiation pattern 20E is formed by light emitted from the sixth light source 9F and reflected by the fourth reflection surface 13D.

That is, adjacent irradiation patterns 20A and 20C are formed by light emitted from the second light source 9B and the third light source 9C constituting the first shared light source 14D, and adjacent irradiation patterns 20D and 20F are formed by light emitted from the fourth light source 9D and the fifth light source 9E constituting the second shared light source 14E. Further, the manner of overlapping the irradiation patterns 20, … … is not changed from the lamp unit 5, and it is assumed that a half area in the irradiation pattern 20B overlaps a half area in the irradiation pattern 20A, a half area in the irradiation pattern 20C overlaps a half area in the irradiation pattern 20B, a half area in the irradiation pattern 20D overlaps a half area in the irradiation pattern 20C, a half area in the irradiation pattern 20E overlaps a half area in the irradiation pattern 20D, and a half area in the irradiation pattern 20F overlaps a half area in the irradiation pattern 20E.

As described above, in the lamp unit 5A, even if the focal length of the reflecting surface is reduced, as in the lamp unit 5, at least half of the regions in the irradiation pattern of the number immediately after and at least half of the regions in the irradiation pattern of the number immediately before are overlapped in the left-right direction, and adjacent irradiation patterns whose regions do not overlap are formed by the light emitted from the common light source, respectively, so that it is difficult for luminance unevenness to occur in the light distribution of the vehicle headlamp 1.

Next, a lamp unit 5B according to a second modification will be described (see fig. 7 and 8).

A first reflecting surface 13e and a second reflecting surface 13f are formed on the reflector 7 of the lamp unit 5B (see fig. 7). The focal lengths of the first reflecting surface 13e and the second reflecting surface 13f of the reflector 7 are set to 10mm to 15mm, for example.

The light sources 9, … … are provided with, for example, 6. Therefore, the number n of light sources 9 is 6. The light sources 9, … … are a first light source 9A, a second light source 9B, a third light source 9C, a fourth light source 9D, a fifth light source 9E, and a sixth light source 9F in this order from the inside to the outside in the lateral direction of the vehicle.

The first light source 9A, the second light source 9B, and the third light source 9C are provided as a first shared light source 14F that emits light toward the first reflection surface 13E, and the fourth light source 9D, the fifth light source 9E, and the sixth light source 9F are provided as a second shared light source 14G that emits light toward the second reflection surface 13F.

In the lamp unit 5B, at least half of the regions in the immediately subsequent numbered illumination patterns and at least half of the regions in the immediately preceding numbered illumination patterns are overlapped in the left-right direction, and adjacent illumination patterns in which the regions do not overlap are formed from the light emitted from the common light source, respectively (see fig. 8). In fig. 8, a case where half regions in the irradiation pattern overlap each other will be described as an example.

Specifically, the irradiation patterns 20A, 20C, and 20E are formed by light emitted from the first light source 9A, the second light source 9B, and the third light source 9C and reflected by the first reflection surface 13E, and the irradiation patterns 20B, 20D, and 20F are formed by light emitted from the fourth light source 9D, the fifth light source 9E, and the sixth light source 9F and reflected by the second reflection surface 13F, respectively.

That is, adjacent irradiation patterns 20A, 20C, and 20E are formed by light emitted from the first light source 9A, the second light source 9B, and the third light source 9C constituting the first common light source 14F, and adjacent irradiation patterns 20B, 20D, and 20F are formed by light emitted from the fourth light source 9D, the fifth light source 9E, and the sixth light source 9F constituting the second common light source 14G. Further, the manner of overlapping the irradiation patterns 20, … … is not changed from the lamp unit 5, and a state is assumed in which a half region in the irradiation pattern 20B overlaps a half region in the irradiation pattern 20A, a half region in the irradiation pattern 20C overlaps a half region in the irradiation pattern 20B, a half region in the irradiation pattern 20D overlaps a half region in the irradiation pattern 20C, a half region in the irradiation pattern 20E overlaps a half region in the irradiation pattern 20D, and a half region in the irradiation pattern 20F overlaps a half region in the irradiation pattern 20E.

As described above, in the lamp unit 5B, even if the focal length of the reflecting surface is reduced, as in the lamp unit 5, by overlapping at least half of the area in the irradiation pattern of the number immediately after and at least half of the area in the irradiation pattern of the number immediately before in the left-right direction, and forming adjacent irradiation patterns in which the areas do not overlap each other from the light emitted from the common light source, it is difficult for luminance unevenness to occur in the light distribution of the vehicle headlamp 1.

In this way, even in the vehicle headlamp 1 using the lamp unit 5A or the lamp unit 5B, the focal length of the reflecting surfaces (13e, 13f) can be reduced in addition to forming the light distribution pattern 21 in which luminance unevenness is less likely to occur, and the vehicle headlamp 1 can be downsized while suppressing the luminance unevenness in the light distribution pattern 21.

The number of reflecting surfaces and the number of light sources in the vehicle headlamp 1 are not limited to the number of lamp units 5, 5A, and 5B described above, and may be other configurations as long as they are plural. The arrangement position of the light source with respect to the reflecting surface is not limited to the arrangement position of the lamp units 5, 5A, and 5B, and one or a plurality of light sources may be arbitrarily arranged on the plurality of reflecting surfaces.

In addition, although the above description has been given of an example in which half of the area in the irradiation pattern of the immediately subsequent number overlaps with half of the area in the irradiation pattern of the immediately preceding number, the overlapping area may be substantially half, and the overlapping area may be half or more. The present invention can also be applied to an example of forming a light distribution pattern as follows: a region of a part of the irradiation pattern of the immediately subsequent number overlaps with a region of a part of the irradiation pattern of the immediately preceding number, and the areas of these overlapping regions are set to be substantially the same area.

Description of the reference numerals

1 vehicle headlamp

7 reflector

9 light source

13a to 13g reflecting surface

14A-14G shared light source

15 non-shared light source

20A-20G irradiation pattern

21 light distribution pattern