JP6755289B2 - Vehicle headlights - Google Patents

Description

The present invention relates to a lamp, and more particularly to a vehicle headlight that forms a light distribution by reflecting light emitted from a light source that emits light in a planar manner by a reflector.

In recent years, the development of vehicle headlights using a light source that emits light in a plane such as an LED (Light Emitting Diode) has been promoted. Halogen bulbs and HID (High Intensity Discharge) bulbs, which are conventional light sources for vehicle headlights, have an omnidirectional irradiation angle (360 degrees), while planar light sources are half spherical (about 180 degrees). One of the features is the irradiation angle of. A headlight using an LED has diagonal and horizontal cut-off lines by reflecting the light source light with a reflector whose reflecting surface is divided into a plurality of segments having different reflection characteristics and synthesizing these projected images. Some form a low beam light distribution pattern. For example, in Patent Document 1, a light source that emits light in a planar manner using an LED is used, and when the reflector is viewed from the front, a hot zone in the light distribution pattern is formed in a segment in the central region, and hot zones in the left and right regions thereof are formed. Headlights have been proposed that form a diffuse zone of the light distribution pattern in the segment.

Japanese Unexamined Patent Publication No. 2012-227103 (FIGS. 1 to 7 and the like)

However, when the low beam light distribution pattern is formed with the above configuration, there is a problem that the illuminance in the vicinity of the cut-off line is weak.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is a lamp for forming a light distribution pattern for a low beam by reflecting light emitted from a light source that emits light in a planar manner with a reflector. By improving the reflector that makes effective use of the characteristics of the light source, it is necessary to provide a headlight for a vehicle in which the illuminance near the cut-off line in the low beam light distribution pattern is increased and the distant visibility is improved.

In order to achieve the above object, in the vehicle headlight according to one aspect of the present invention, a light source that emits light in a planar manner and an oblique light emitted by the light source are reflected forward and intersect at an elbow point. A plurality of reflectors having a cut-off line and a horizontal cut-off line to form a light distribution pattern for a low beam, the light source is arranged above or below the reflector, and the reflector has different reflection characteristics on its reflection surface. The segment comprises a first region having a large arrangement angle of the light source from the light emitting surface and a second region having a small arrangement angle of the light source from the light emitting surface when the reflector is viewed from the front. A hot zone of the light distribution pattern is formed, and a diffusion zone of the light distribution pattern is formed in a third region in the arrangement angle between the first region and the second region, and the first region is The second region is a region extending around an arrangement angle of 75 degrees with a line orthogonal to the light emitting surface of the light source, and the second region is a region extending around an arrangement angle of 0 degrees to 15 degrees.

According to this configuration, in consideration of the characteristics of the light source image of the planar light source that emits light in a planar manner, the second region, which was conventionally used for forming a diffusion pattern, has been changed to a hot zone forming application. The illuminance can be increased. That is, unlike a point light source or a three-dimensional light source, a planar light source is reflected in a smaller light source image as the arrangement angle with the light source is smaller. In particular, by using the second region where the arrangement angle with the light source extends from 0 degrees to 15 degrees for hot zone formation, this characteristic is fully utilized to create a narrow and high luminosity light source image in the hot zone. Can be projected (combined) intensively, so that the illuminance in the hot zone can be increased.

In the above aspect, it is also preferable that the segment of the second region that mainly irradiates the own lane side irradiates the region of the hot zone that includes the diagonal cut-off line including the elbow point.

According to this configuration, the narrow and high-luminosity light source image reflected in the second region is projected intensively in the region including the diagonal cut-off line near the elbow point, so that the illuminance in the vicinity of the diagonal cut-off line can be increased. it can.

In the above aspect, it is also preferable that the segment of the second region that mainly irradiates the oncoming lane side irradiates the region of the hot zone that includes the horizontal cut-off line including the elbow point.

According to this configuration, the narrow and high-luminosity light source image reflected in the second region is projected intensively in the region including the horizontal cut-off line near the elbow point, so that the illuminance in the vicinity of the horizontal cut-off line can be increased. it can.

In the above aspect, it is also preferable that the light source is arranged so that the right end or the left end of the light emitting surface coincides with the focal point of the reflector.

According to this configuration, the projected image of the planar light source can be formed so as to be more attached to the oblique cut-off line, so that the distance visibility is further improved.

According to the present invention, the illuminance in the hot zone of the low beam light distribution pattern is increased, and the distant visibility is improved.

Front view of a vehicle headlight according to an embodiment of the present invention Longitudinal section of the headlight Perspective view of a planar light source The figure which shows the light distribution pattern for a low beam formed on a virtual vertical screen by a lamp unit. Front view of the reflector to explain the configuration of the reflective surface 6 (a) is a light source image of the planar light source seen from the viewpoint A of FIG. 1, FIG. 6 (b) is a light source image of the planar light source seen from the viewpoint B of FIG. 1, and FIG. 6 (c) is. , Light source image of the planar light source seen from the viewpoint C in FIG. FIG. 7 (a) is a diagram schematically showing a segment included in the second hot zone forming portion, and FIG. 7 (b) is for a hot zone formed on a virtual vertical screen by the segment of FIG. 7 (a). Diagram showing the light distribution pattern FIG. 8 (a) is a diagram schematically showing a segment included in the third hot zone forming portion, and FIG. 8 (b) is for a hot zone formed on a virtual vertical screen by the segment of FIG. 8 (a). Diagram showing the light distribution pattern FIG. 9 (a) is a diagram schematically showing a segment included in the first hot zone forming portion, and FIG. 9 (b) is a diagram for a hot zone formed on a virtual vertical screen by the segment of FIG. 9 (a). Diagram showing the light distribution pattern Comparative diagram of the light distribution according to the embodiment of the present invention and the light distribution according to the conventional embodiment.

Next, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of the vehicle headlight 10 according to an embodiment of the present invention, and FIG. 2 is a vertical sectional view of the headlight 10 (cross-sectional view taken along line II-II of FIG. 1).

The vehicle headlight 10 is defined by a box-shaped lamp body 2 having an opening and a front cover 4 made of a translucent resin or glass attached to the opening. A lamp unit 6 is provided in the lamp chamber. The vehicle headlights 10 are provided on the left and right sides of the front portion of the vehicle, respectively, and the following configurations are common to the left and right sides. As shown in the figure, the direction of the front cover 4 is the front (arrow F) referred to in the present specification, and the direction of the lamp body 2 is the rear (arrow B) referred to in the present specification.

The lamp unit 6 includes a planar light source 11 as a light source, a reflector 12, a vertical support plate 14 and a horizontal support plate 15 as support members thereof. In front of the lighting chamber of the lighting unit 6, an extension (not shown) for blindfolding the configuration of the lighting unit 6 from the front of the lighting is provided in an area other than the light emitting area.

Three of the corners of the vertical support plate 14 are fixed to the lamp body 2 by the aiming screw 16, and the vertical support plate 14 can be tilted and adjusted in the vertical and horizontal directions. The horizontal support plate 15 is fixed to the front surface of the vertical support plate 14. The planar light source 11 is attached to the lower surface of the horizontal support plate 15. The horizontal support plate 15 is made of a metal having high thermal conductivity such as aluminum, and the upper surface of the horizontal support plate 15 is integrally formed with heat radiation fins 17 and functions as a heat sink. Therefore, the heat generated by the planar light source 11 is efficiently cooled via the heat radiating fins 17.

FIG. 3 is a perspective view of the planar light source 11. The planar light source 11 is a light emitting module having a plurality of LED chips 21 and a phosphor 22 on a substrate 23 made of aluminum nitride. Four 1 mm square LED chips 21 are arranged side by side in a row. A blue LED that mainly emits blue light is adopted as the LED chip 21. The phosphor 22 is linearly applied on the row of the LED chips 21. As the phosphor 22, a phosphor that converts blue light into yellow light is adopted. When the LED chip 21 emits light, the blue light emitted by the LED chip 21 and the yellow light wavelength-converted by the phosphor 22 are mixed, and white light is emitted from the surface of the phosphor 22. That is, the planar light source 11 has a light emitting surface (surface of a phosphor) 22a that emits light in a rectangular shape, and has an irradiation angle of 180 degrees with respect to the direction in which the light emitting surface 22a is directed. The value of this irradiation angle does not have to be exactly 180 degrees, and may be a value before or after that. Further, the LED chip 21 may mainly emit a wavelength other than blue, such as ultraviolet light. The above is an example of the number and shape of the LED chips 21, and the LED chips 21 may be arranged in a plane so that they can emit light. Since the phosphor 22 is known, details thereof will be omitted.

The reflector 12 is an optical member having a reflecting surface 12a formed with a rotating paraboloid as a basic shape, and reflects the light emitted by the planar light source 11 forward to form a low beam light distribution pattern PL described later. To do. The base end of the reflector 12 is attached below the horizontal support plate 15 and in front of the vertical support plate 14. That is, the planar light source 11 is provided in the direction perpendicular to the optical axis Ax of the reflector 12 (see FIG. 2). This meaning means that the planar light source 11 is arranged above or below the optical axis Ax of the reflector 12, and as shown in FIG. 2, the light emitting surface 22a of the planar light source 11 is not necessarily arranged. It is not necessary to arrange the surface light source 11 so that the optical axis Ay of the planar light source 11 intersects the optical axis Ax of the reflector perpendicularly. That is, the light emitting surface 22a of the planar light source 11 may be arranged so as to be inclined in the front-rear direction of the lamp, and the optical axis Ay of the planar light source 11 and the optical axis Ax of the reflector may be provided so as to be inclined and intersect.

The reflection surface 12a of the reflector 12 is divided into a plurality of segments having different reflection characteristics, which will be described later. Each segment is formed as a smooth curved surface, and adjacent segments are connected to each other through a step or a crease. Each segment of the reflector 12 has a first hot zone forming portion 31, a second hot zone forming portion 32, a third hot zone forming portion 33, a first diffusion zone forming portion 41, and a second diffusion zone, which will be described later. It is divided into forming portions 42. The projected images reflected by each of these segments are combined to form the following low beam light distribution pattern PL.

FIG. 4 is a diagram showing a low beam light distribution pattern PL formed on a virtual vertical screen by the lamp unit 6. The lamp unit 6 reflects the light emitted by the planar light source 11 in front of the lamp on the reflecting surface 12a, and diagonally cuts off-line CL2 and horizontally on a virtual vertical screen virtually erected 25 m in front of the lamp. A low beam light distribution pattern PL having a cut-off line CL1 is formed. The horizontal cut offline CL1 is a line extending parallel to the HH line on the right side of the VV line on the virtual vertical screen, and the diagonal cut offline CL2 is the horizontal cut offline CL1 and VV line on the virtual vertical screen. It is a line that rises from the intersection of the above to the left with an inclination of 15 degrees with respect to the HH line.

The low beam light distribution pattern PL includes an oblique cut-offline CL2 and a horizontal cut-offline CL1 in the vicinity of the vanishing point (intersection of the HH line and the VV line) on the virtual vertical screen, and other areas (described later). It has a hot zone PA with higher illuminance than the PB region). Further, in the left region of the VV line, below the horizontal cut-off line CL1, in the right region of the VV line, below the HH line, in the horizontal region wider than the hot zone PA, and in the HH line. An extension of the diagonally cut offline CL2 above has a widespread diffusion zone PB. The low beam light distribution pattern PL is formed by synthesizing the diffusion zone PB and the hot zone PA.

Hereinafter, the configuration of the reflecting surface 12a of the reflector 12, which is the gist of the present application, will be described in detail.

FIG. 5 is a front view of the reflector 12 for explaining the configuration of the reflection surface 12a. The reflecting surface 12a of the reflector is formed between a region θb having a large arrangement angle θ from the light emitting surface 22a of the planar light source 11 and a region θs having a small arrangement angle θ from the light emitting surface 22a when the reflector 12 is viewed from the front. The arrangement angle θ from the light emitting surface 22a is a region θm in the middle.

Here, in the present specification, the arrangement angle θ means that the reflector 12 is viewed from the front, the center of the light emitting surface 22a of the planar light source 11 is set as a reference point, and the reference point is passed in the longitudinal direction of the light emitting surface 22a. It is assumed that the stretched line is 0 degrees as the horizontal reference, and the line orthogonal to the light emitting surface 22a at the reference point is 90 degrees, and can be expressed by 0 ° ≤ θ ≤ 90 °. That is, the arrangement angle θ is defined on the reflecting surface 12a in each of the left side region and the right side region with the 90 degree line as a boundary. Therefore, the region θs having a small arrangement angle, the region θm in the arrangement angle, and the region θb having a large arrangement angle exist in pairs on the left and right sides of the reflection surface 12a of the reflector.

A first hot zone is formed in the region θb having a large placement angle, that is, in the region around the placement angle of 90 degrees, preferably from around the placement angle of 75 degrees to 90 degrees (from the 90 degree line to around 15 degrees to the left and right). The portion 31 is formed.

In the region θs with a small placement angle, that is, around the placement angle of 0 degrees, preferably around 0 to 15 degrees of the placement angle, the second hot zone forming portion 32 is on the left side and the third hot zone is on the right side. The forming portion 33 is formed. The term "periphery" as used herein means, for example, that the term "periphery" does not mean that it is strictly on the 15-degree line, but includes a region of plus or minus several tens of degrees on the 15-degree line. To do.

The region between the region θs with a small placement angle and the region θb with a large placement angle is the region θm in the placement angle, with the first diffusion zone forming portion 41 on the left side and the second diffusion zone forming on the right side. The portion 42 is formed.

The first hot zone forming portion 31, the second hot zone forming portion 32, and the third hot zone forming portion 33 form the above hot zone PA, and the first diffusion zone forming portion 41 and the second hot zone forming portion 41 and the second The diffusion zone forming portion 42 forms the above-mentioned diffusion zone PB. The first hot zone forming portion 31, the second hot zone forming portion 32, and the third hot zone forming portion 33 have a region θs with a small arrangement angle or an arrangement angle in order to avoid complication of the shape of the reflector 12. It is not necessary to use all the regions of the large region θb, and it is preferable that the region θs having a small arrangement angle and the region θb having a large arrangement angle are provided at the maximum in the area that can be formed.

Here, in the configuration of the reflector of Patent Document 1, when the reflector is viewed from the front, a hot zone PA is formed in a segment in the central region, that is, a region θb having a large arrangement angle, and segments in other regions, that is, small and medium arrangement angles. The diffusion zone PB is formed in the regions θs and θm. In contrast to this configuration, in the reflector 12 of the present embodiment, the second hot zone forming portion 32 and the third hot zone forming portion 33 are located in the region θs having a small arrangement angle conventionally used for forming the diffusion zone PB. It is formed. This portion was adopted for forming the hot zone PA in order to make the best use of the characteristics of the light source image of the planar light source 11. This will be described below.

6 (a) is a light source image of the planar light source 11 seen from the viewpoint A of FIG. 1, and FIG. 6 (b) is a light source image of the planar light source 11 seen from the viewpoint B of FIG. 1, FIG. 6 (c). ) Is a light source image of the planar light source 11 as seen from the viewpoint C in FIG.

Looking at the planar light source 11 from the viewpoint A (approximately the center position on the 90-degree arrangement angle line) of FIG. 1, the light emitting surface 22a (hereinafter, also referred to as the light source image 22i) of the planar light source 11 is shown in FIG. 6 (a). It looks like a rectangle. On the other hand, when the planar light source 11 is viewed from the viewpoint B of FIG. 1, which is located farther from the planar light source 11 than the viewpoint A in the same direction, the light source image 22i is as shown in FIG. 6 (b). It looks smaller than the light source image 22i of the viewpoint A. Further, although the distance from the planar light source 11 is about the same as that of the viewpoint A, when the planar light source 11 is viewed from the viewpoint C of FIG. 1, which is a position where the arrangement angle θ is smaller than that of the viewpoint A, the light source image 22i is shown in FIG. As shown in 6 (c), it looks like a trapezoid smaller than the light source image 22i of the viewpoint A and the viewpoint B.

As described above, the light source image 22i of the planar light source 11 is reflected in a smaller light source as the distance from the light source increases and the arrangement angle θ from the light source decreases. Therefore, when the light source image 22i is projected, a projected image having high luminosity can be formed in a narrow range. In a point light source or a three-dimensional light source, such a difference in the light source image due to an angle or a distance does not occur as much as in a planar light source, and this is a characteristic unique to a planar light source.

Based on this, regarding the first hot zone forming portion 31, the second hot zone forming portion 32, the third hot zone forming portion 33, the first diffusion zone forming portion 41, and the second diffusion zone forming portion 42. The details will be described.

The segment of the first diffusion zone forming portion 41 is formed by dividing the region into four rows in the left-right direction and three rows in the up-down direction. The segments in the third row from the left and the third row from the top are further divided into two, and as a result, the first diffusion zone forming portion 41 has 13 segments (see FIG. 5). Each of the segments of the first diffusion zone forming portion 41 forms a projected image extending to the left below the HU line on the virtual vertical screen.

The segment of the second diffusion zone forming portion 42 is formed by dividing the region into four rows in the left-right direction and three rows in the up-down direction. As a result, the second diffusion zone forming portion 42 has 12 segments (see FIG. 5). Each of the segments of the second diffusion zone forming portion 42 forms a projected image extending to the right below the HU line on the virtual vertical screen. These are combined to form a diffusion zone PB. Details of this light distribution will be omitted because it is described in Patent Document 1.

FIG. 7A is a diagram schematically showing segments A321 and A322 included in the second hot zone forming portion 32, and FIG. 7B is a virtual vertical in segments A321 and A322 of FIG. 7A. It is a figure which shows the light distribution pattern PA321, PA322 for a hot zone formed on a screen.

The second hot zone forming portion 32 includes a hypotenuse-shaped segment A321 having a hypotenuse having a hypotenuse substantially parallel to the hypotenuse 15 degree line in a region of an arrangement angle of 0 to 15 degrees, and a region of an arrangement angle of 15 to 30 degrees. A parallel quadrilateral segment A322 having a hypotenuse substantially parallel to the arrangement angle 15 degree line is formed therein. The number of segment divisions of the second hot zone forming portion 32 may be arbitrary in the vertical and horizontal directions, and the number of divisions may be increased particularly around the arrangement angle of 15 to 30 degrees in order to facilitate the light distribution design. The segments A321 and A322 project the light source image 22i of the planar light source 11 and form rectangular projection images PA321 and PA322 in the hot zone PA at positions where one long side thereof substantially coincides with the oblique cut-off line CL2. To do. The segment A321 forms a projection image PA321 narrower than the projection image PA322 by utilizing the fact that the arrangement angle θ is smaller than that of the segment A322.

FIG. 8A is a diagram schematically showing the segment A331 included in the third hot zone forming portion 33, and FIG. 8B is a diagram formed on the virtual vertical screen by the segment A331 of FIG. 8A. It is a figure which shows the light distribution pattern PA331 for a hot zone.

In the third hot zone forming portion 33, a rectangular segment A331 having a horizontal side is formed in a region where the arrangement angle is 0 to 15 degrees. The number of segment divisions of the third hot zone forming portion 33 may be arbitrary in the vertical and horizontal directions. The segment A331 projects the light source image 22i of the planar light source 11 and forms a rectangular projected image PA331 in the hot zone PA at a position where approximately half of one long side thereof substantially coincides with the horizontal cut-off line CL1. ..

FIG. 9 (a) is a diagram schematically showing segments A311 to A319 included in the first hot zone forming portion 31, and FIG. 9 (b) is a virtual vertical in segments A31 to A319 of FIG. 9 (a). It is a figure which shows the light distribution pattern PA311-PA319 for a hot zone formed on a screen.

The first hot zone forming portion 31 is largely divided into two rows in the left-right direction, and segments A311 to A313 in the left region and segments A314 to A319 in the right region are formed. The segments A311 to A313 in the left region are divided into three rows in the vertical direction, and the segments A311, A312, and A313 are formed in order from the top. The segments A314 to A319 in the right region are divided into six rows in the vertical direction, and the segments A314, A315, A316, A317, A318, and A319 are formed in this order from the top. The segments A315 to A319 are further divided in the left-right direction, and segments A315'to A319' are formed on the left side and segments A315'to A319' are formed on the right side.

The segments A311 to A313 in the left region and the segments A314 in the right region are formed in a rectangular shape. The segment A315 in the right region is divided into a hypotenuse-shaped segment A315 ′ on the left side and a hypotenuse-shaped segment A315 ″ on the right side by an arrangement angle 75 degree line (15 degrees from the 90 degree line). The segment A316 is divided into a hypotenuse-shaped segment A316 ′ on the left side and a parallel quadrilateral segment A316 ″ on the right side by an arrangement angle 76 degree line (around 15 degrees from the 90 degree line). The segment A317 is divided into a hypotenuse-shaped segment A317 ′ on the left side and a parallel quadrilateral segment A316 ″ on the right side by an arrangement angle 78 degree line (around 15 degrees from the 90 degree line). The segment A318 is divided into a hypotenuse-shaped segment A318 ′ on the left side and a parallel quadrilateral segment A318 ″ on the right side by an arrangement angle 80 degree line (around 15 degrees from the 90 degree line). The segment A319 is divided into a hypotenuse trapezoidal segment A319 ′ on the left side and a parallel quadrilateral segment A319 ″ on the right side by an arrangement angle 82 degree line (around 15 degrees from the 90 degree line). Of these, the segments A316 ″ to A319 ″ are portions that are extended toward the diffusion zone forming portion side of the hot zone forming portion of Patent Document 1. The number of segment divisions of the first hot zone forming portion 31 may also be arbitrary in the vertical and horizontal directions. The left and right divisions of the segments A315 to A319 are made to facilitate the light distribution design, and the projected images are the same on the left and right. Therefore, one of them is the projected image PA315 to A319. It is illustrated as.

The segments A311 to A313 in the left region project the light source image 22i of the planar light source 11, and the projected images PA311 to PA313 form a horizontal region of the hot zone PA. The segment A314 in the right region projects the light source image 22i of the planar light source 11 to form a wide region of the hot zone PA extending substantially parallel to the oblique cut-off line CL2 in the projected image PA314. Details of this light distribution will be omitted because it is described in Patent Document 1.

On the other hand, the segments A315 to A319 (segments A315'to A319' and segments A315'to A319''in the right region project the light source image 22i of the planar light source 11 and project the projected image PA314 into the hot zone PA. A rectangular projection image PA315 to PA319, which is narrower than the above, is formed at a position where one long side thereof substantially coincides with the oblique cut-off line CL2. By utilizing the characteristics of the planar light source, the segments A315 to A319 are narrower and have higher luminosity in the order of the longer the arrangement distance from the planar light source 11, that is, the segments A319, A318, A317, A316, and A315. The projected images PA319, PA318, PA317, PA316, and PA315 are formed in a direction approaching the vanishing point.

According to the above configuration, the hot zone PA is formed in the segments A321, A322, and A331 of the region θs in which the arrangement angle from the light source is small, in consideration of the characteristics of the light source image 22i of the planar light source 11. The illuminance of the hot zone PA increases.

In particular, the narrow and high-luminosity projection images PA321 and PA322 of the second hot zone forming portion 32 that mainly illuminates the own lane traveling side in the region θs with a small arrangement angle are concentrated along the diagonal cut-off line CL2. The illuminance in the vicinity of the oblique cut-off line CL2 is increased by projecting the image. Further, in the region θs with a small arrangement angle, the narrow and high-luminosity projection image PA331 of the third hot zone forming portion 33 that mainly illuminates the oncoming lane side is intensively projected along the horizontal cut-off line CL1. By doing so, the illuminance in the vicinity of the horizontal cut-off line CL1 is increased.

Further, in the region θb having a large arrangement angle, the region on the side of the third hot zone forming portion 33 (the region on the side that illuminates the region including the horizontal cut-off line of the region having a small arrangement angle) is arranged from the planar light source. A narrow and high-luminosity projection image PA315-PA319 of segments A315-A319 (particularly segments A316 ″, A317 ″, A318 ″, A319 ″) in a distant region is cut along an oblique cut-off line CL2. The illuminance in the vicinity of the oblique cut-off line CL2 is further increased by the intensive projection.

Here, the reflector 12 increases the illuminance of the diagonally cut offline CL2 at the second hot zone forming portion 32 at a position suitable for irradiating the traveling side of the own lane in the region θs with a small arrangement angle. The third hot zone forming portion 33, which is mainly located at a position suitable for irradiating the oncoming lane side, is used to increase the illuminance of the horizontal cut-off line CL1. As a result, the low beam light distribution pattern PL can be formed according to the light distribution characteristics of the basic shape of the reflector 12, so that the shape of the reflector 12 is not complicated.

FIG. 10 is a comparison diagram of the light distribution according to the embodiment of the present invention and the light distribution according to the conventional embodiment. This shows the light distribution pattern on the horizontal road surface in a plan view, and the vertical axis shows the reachable distance of the irradiation light from the vehicle headlight. The broken line P1 is obtained by the conventional reflector configuration of Patent Document 1, and the solid line P2 is obtained by the configuration of the reflector 12 of this embodiment. According to FIG. 10, it can be seen that the configuration of the reflector 12 of this embodiment extends the maximum reachable distance of the irradiation light and improves the distant visibility.

It should be noted that preferably, the planar light source 11 is "horizontally placed" in which the longitudinal direction of the light emitting surface 22a of the planar light source 11 is not in the front-rear direction (FB direction) of the lamp but in the left-right direction (LR direction). Place with. Further, it is preferable that the planar light source 11 is arranged horizontally so that the right end 22aR of the light emitting surface 22a coincides with the focal point F1 of the reflector 12 (see FIG. 1). As a result, it is possible to form a projected image that sticks to the more oblique cut-off line CL2, which leads to further improvement of distant visibility.

With the configuration of the reflector 12, the light source of the vehicle headlight 10 may be one of the planar light sources 11.

In the above-described embodiment, the reflector 12 is arranged below the planar light source 11, but the reflector 12 may be arranged above the planar light source 11 with the optical axis Ay of the planar light source 11 above. good.

Further, although the above-described embodiment has a configuration in the left light distribution, when the right light distribution is used, the above configuration may be reversed left and right. At this time, the focal point F1 of the reflector 12 may be aligned with the left end 22aL of the light emitting surface 22a of the planar light source 11.

2 ... Lamp body, 4 ... Front cover, 6 ... Lighting unit, 10 ... Vehicle headlight, 11 ... Planar light source, 12 ... Reflector, 12a ... Reflector reflection surface, 22a ... Planar light source light emitting surface, 22aR , 22aL ... Short side edge of light emitting surface, 22i ... Light source image, 31 ... First hot zone forming part, 32 ... Second hot zone forming part, 33 ... Third hot zone forming part, 41 ... First Diffusion zone forming part, 42 ... Second diffusion zone forming part, Ax ... Reflector optical axis, θ ... Placement angle, θb ... Placement angle large area, θs ... Placement angle small area, θm ... Placement angle Area, PL ... Low beam light distribution pattern, CL2 ... Diagonal cut offline, CL1 ... Horizontal cut offline, PA ... Hot zone, PB ... Diffusion zone A311-A319, A321-A322, A331 ... Segment, PA311-PA319, PA321-PA322 , PA331 ... Projection image of segment

Claims (4)

A light source that emits light in a plane and
A reflector that reflects the light emitted by the light source forward to form a low beam light distribution pattern having diagonal cut-offline and horizontal cut-off line that intersect at elbow points.
The light source is located above or below the reflector.
The reflector has a plurality of segments having different reflection characteristics on its reflection surface.
The segment is viewed from the front of the reflector.
The first region where the arrangement angle of the light source from the light emitting surface is large, and
A hot zone of the light distribution pattern is formed in the second region where the arrangement angle of the light source from the light emitting surface is small.
A diffusion zone of the light distribution pattern is formed in the third region in the arrangement angle between the first region and the second region.
The first region is a region extending around an arrangement angle of 75 degrees with a line orthogonal to the light emitting surface of the light source.
The second region is a region extending around an arrangement angle of 0 to 15 degrees.
In the second region, the light emitted by the light source is directly incident and reflected forward .
Among the segments of the second region, those that mainly irradiate the own lane side illuminate the region of the hot zone including the diagonal cut-off line including the elbow point. light. The vehicle front according to claim 1, wherein at least a part of the second region and the first region are arranged in a direction in which the light source emits light with the reflector viewed in front. Light source. Among the segments of the second region, primarily irradiates the opposite lane side, according to claim 1, characterized in that irradiating range including the horizontal cutoff line including the elbow point of the hot zone or vehicle headlamp described in 2. The vehicle headlight according to any one of claims 1 to 3 , wherein the light source is arranged so that the right end or the left end of the light emitting surface is aligned with the focal point of the reflector.

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