JPH0364962B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The vehicle headlamp of the present invention will be explained in accordance with the following items.

A. Industrial field of application B. Summary of the invention C. Prior art [Fig. 8] D. Problem to be solved by the invention E. Means for solving the problem F. Example F-1 First example [1st example] Figures to Figures 4] a Reflector b Light shield c Projection lens d Light distribution pattern F-2 Second embodiment [Figures 5 to 7] a Reflector b Light shield c Projection lens d Light distribution pattern G Effects of the Invention (A. Field of Industrial Application) The present invention relates to a novel vehicle headlamp. Specifically, the present invention relates to a vehicle headlamp that uses a projection lens to obtain a desired light distribution pattern using the principle of a projector, and is designed to easily obtain the desired light distribution pattern.

(B. Summary of the Invention) The vehicle headlamp of the present invention includes a plurality of reflecting mirrors each having a first focal point and a reflecting surface having a second focal area, each having a common first focal point, and each optical axis having its own optical axis. Light shielding bodies are arranged so as to extend in different directions, and each of the light shielding bodies has a light shielding edge located near the second focal range of each reflecting mirror, and in front of each light shielding body, the focal range is located on the light shielding edge of the corresponding light shielding body. A single light distribution pattern is obtained by composing partial light distribution patterns projected by a plurality of projection units, each consisting of a reflecting mirror, a light shielding body, and a projection lens, by respectively arranging projection lenses that are approximately located in the same position. With this, a desired light distribution pattern can be obtained extremely easily.

(C. Prior Art) [Fig. 8] There is a so-called projection type headlamp for vehicles.

FIG. 8 shows an example a of a projection type vehicle headlamp.

b is a reflecting mirror equipped with a reflecting surface c having a first focal point and a second focal region, d is a light source disposed at the first focal point of the reflecting surface c, and e is a light shield, the upper edge of which is A light-shielding edge f is arranged near the second focal region of the reflective surface c. g is a projection lens placed in front of the light shield e, and its focal point is located on the light shield edge f of the light shield e.

In this vehicle headlamp a, when looking at a plane perpendicular to the optical axis of the reflector b at the part where the light shielding edge f is located, there are a light shield e and a light shield e. There is an image consisting of the light portion located above the light-shielding edge f of . Since the focal point of the projection lens g is located on the light-shielding edge f, the image is projected forward in an inverted state.

(D) Problem to be Solved by the Invention In the vehicle headlight a described above, the light distribution pattern, especially the bright and dark boundary line that limits the upper edge, is clearly formed. Headlights, especially
It is suitable as an automobile headlamp that emits a passing beam.

However, while it is important for the light distribution pattern of automobile headlamps to have a clear pattern shape, especially the bright and dark boundaries, there are other factors, such as the sideways of the light distribution. A certain degree of expansion is also necessary.

For example, if you want to spread the light distribution to the left and right using the vehicle headlight a mentioned above,
The problem is that the vertical width also increases, creating an unnecessary portion at the bottom and blurring the bright/dark boundary line.

However, if you try to reduce the vertical width of the light distribution, you will have to block a lot of light with the light shield e, which will cause a large loss of light, and the problem of blurring the bright and dark boundary will be solved. do not.

(E. Means for Solving Problems) In order to solve the above-mentioned problems, the vehicle headlamp of the present invention includes a plurality of reflecting mirrors each having a reflecting surface having a first focal point and a second focal region. Each light shield is arranged so that the first focal point is common and each optical axis extends in a different direction, and a light shield whose light shielding edge is located near the second focal region of each reflecting mirror is arranged. Projection lenses are arranged in front of each other, with their focal areas located approximately on the light-shielding edge of the corresponding light-shielding body.

Therefore, according to the vehicle headlamp of the present invention, a plurality of partial light distribution patterns projected by a plurality of projection units each comprising a common light source, a separate reflecting mirror, a light shielding body, and a projection lens are provided. Since a single light distribution pattern is obtained by combining them, a desired light distribution can be obtained extremely easily, and waste of light can be eliminated.

(F. Embodiment) Details of the vehicle headlamp of the present invention will be described below with reference to illustrated embodiments.

(F-1 First Embodiment) [Figures 1 to 4] Figures 1 to 4 show the first embodiment of the vehicle headlamp of the present invention.
This is an example of the following. This first example 1
The present invention is applied to an automobile headlamp for emitting a low beam beam.

(a reflecting mirror) 2 is a reflector, and four reflecting mirrors 3 ₁ , 3 ₂ , 3
₃ , 3 and ₄ are integrally formed.

Each of the reflecting mirrors 3 ₁ to 3 ₄ is provided with reflecting surfaces 4 ₁ , 4 ₂ , 4 ₃ , and 4 ₄ each forming a part of an ellipsoid of revolution. That is, the reflecting surface 4 ₁ has a shape of approximately the upper third of an ellipsoid of revolution, the reflecting surface 4 ₂ has a shape of approximately the lower third of an ellipsoid of revolution, and the reflecting surface 4 ₃ has a shape of approximately the lower third of an ellipsoid of revolution. The reflective surface 44 has the shape of approximately the left half of an ellipsoid, and the reflecting surface ₄₄ has the shape of approximately the right half of the ellipsoid of revolution.

The left edge of the reflecting mirror 3 ₁ and the upper edge of the reflecting mirror 3 ₃ are connected by the connecting part 5 ₁ , and the right edge of the reflecting mirror 3 ₁ and the upper edge of the reflecting mirror 3 ₄ are connected by the connecting part 5 ₂ . Well, reflector 3
The _left side edge of the reflector 32 and the lower edge of the reflector ₃₃ are integrally connected by a connecting part ₅₃ , and the right side edge of the reflective mirror ₃₂ and the lower edge of the reflective mirror ₃₄ are integrally connected by a connecting part ₅₄ . As a result, a reflector 2 in which the respective reflectors 3 ₁ to 3 ₄ are integrated is formed.

The reflecting surfaces 4 ₁ to 4 ₄ of the reflecting mirrors 3 ₁ to 3 ₄ have a common first focal point f ₀ . In addition, each reflective surface 4
₁ to ₄ have their optical axes extending in different directions. That is, the optical axes x ₁ and x ₂ of the reflective surfaces 4 ₁ and 4 ₂ are substantially coaxial, and they extend straight toward the front. The optical axis x ₃ of the reflective surface 4 ₃ is the reflective surface 4 ₁ , 4
_The optical axis x ₄ of the reflecting surface _{4 4 is} inclined to the right with respect to the optical axes x _{1 and} x ₂ . Note that f ₁ is the second focal point of the reflective surface 4 ₁ , f ₂ is the second focal point of the reflective surface 4 ₂ , f ₃ is the second focal point of the reflective surface 4 ₃ , and f ₄ is the second focal point of the reflective surface 4 ₄ . be. and,
The second focal points f ₁ and f ₂ of the reflecting surfaces 4 ₁ and 4 ₂ are located at approximately the same location.

Reference numeral 6 denotes a light source, for example, a filament of a light bulb, and is arranged at a position including the first focal point f ₀ .

Therefore, light is emitted from the light source 6, and each reflecting mirror 3 ₁
The light reflected by the reflective surfaces 4 _{1 to} 4 ₄ of the reflective surfaces 4 ₁ to 4 4 is focused on the second focal points f ₁ to f ₄ of the reflective surfaces 4 1 to 4 ₄ .
However, even though the light is focused, the light source 6 is not a point but has a certain size, so the optical axis is x ₁ to x _4.
The light is focused within a certain spread range within a plane perpendicular to .

(b light shielding body) 7 is a light shielding plate, and three light shielding bodies 8 ₁ , 8 ₂ , 8
₃ are integrally formed.

That is, the light shielding body 8 ₁ is located at the center, and the light shielding bodies 8 ₂ and 8 ₃ are integrally connected on both sides thereof. And upper edges 9 ₁ , 9 ₂ , 9 ₃ of each light shielding body 8 ₁ , 8 ₂ , 8 ₃
serves as a light-shielding edge. Then, the left and right light shields 8
The light-shielding edges 9 ₂ , 9 ₃ of ₂ , 8 ₃ extend horizontally,
The light-shielding edge 9 ₁ of the central light-shielding body 8 ₁ has a portion 9 ₁ ′ on the left side of the center formed as a diagonal edge downward to the left.
The centers of the light shielding edges ₉₁ to ₉₃ of the light shielding bodies ₈₁ to ₈₃ are close to the optical axes _x1 to _x4 of the reflecting surfaces ₄₁ to ₄₄ , and the respective second focal points _f1 to Located in close proximity to _f4 . That is, the light-shielding edge 9 ₁ of the central light-shielding body 8 ₁ has its central portion aligned with the optical axes x ₁ , x ₂ of the central reflecting surfaces 4 ₁ , 4 ₂ and their second focal point f ₁ ,
The light shielding edge 9 ₂ of the left light shield 8 ₂ is in contact with the optical axis x ₃ of the left reflecting surface 4 ₃ from approximately below near its second focal point f _{3 .} The light-shielding edge 9 ₃ of the right-hand light shield 8 ₃ is arranged at a position where it touches the optical axis x ₄ of the right-hand reflective surface 4 ₄ near its second focal point f ₄ from approximately below.

Therefore, the light-shielding edge 9 of each light-shielding body 8 ₁ , 8 ₂ , 8 ₃
Each optical axis x ₁ , _{x 2} , x ₃ , x ₄ at the position of ₁ , 9 ₂ , 9 _3
When viewed _{in a cross section perpendicular to} A bundle of reflected light exists as an image.

(c projection lens) 10 ₁ , 10 ₂ and 10 ₃ are projection lenses,
10 ₁ is arranged in front of the center light shield 8 ₁ , 10 ₂ is arranged in front of the left light shield 8 ₂ , and 10 ₃ is arranged in front of the receiving side light shield 8 ₃ .

The projection lens 10 ₁ has a convex lens shape, and its focal point F ₁ is located at the center of the light shielding edge 9 ₁ of the central light shield 8 ₁ . The projection lenses 10 ₂ and 10 ₃ located on the left and right sides of the projection lens 10 have a semi-cylindrical shape, and are arranged so that they have a rectangular shape in a horizontal cross section and a convex lens shape in a vertical cross section. Therefore, the focal points of these projection lenses 10 ₂ and 10 ₃ appear not as points but as lines extending horizontally (hereinafter referred to as "focal lines").

The projection lens 10 ₂ is arranged in front of the light shield 8 ₂ , and its focal line F ₂ is located along the light shield edge _{9 2 of} the light shield 8 2 . Further, the projection lens 10 ₃ is arranged in front of the light shielding body 8 ₃ , and its focal line F ₃ is located along the light shielding edge 9 ₃ of the light shielding body 8 ₃ .

(d Light Distribution Pattern) Therefore, in the case of the above-mentioned automobile headlamp 1, a passing beam is emitted according to the light distribution pattern described below.

The light reflected by the reflecting surfaces 4 ₁ and 4 ₂ of the reflecting mirrors 3 ₁ and 3 ₂ has its lower edge limited by the light shield 8 ₁ and is projected forward by the projection lens 10 ₁ as an inverted image. Therefore, the light distribution pattern 11 ₁ shown in FIG.
11 ₂ .

In addition, the light reflected by the reflecting surfaces 4 ₃ and 4 ₄ of the reflecting mirrors 3 ₃ and 3 ₄ has an image whose lower edge is limited by the light shields 8 ₂ and 8 ₃ that is projected onto the projection lenses 10 ₂ and 10 _{3 .} However, since the projection lenses 10 ₂ and 10 ₃ have a light-condensing property in the vertical plane but not in the horizontal plane, Light distribution pattern 1 with wide diffusion width
1 ₃ , 11 ₄ and the optical axes of reflective surfaces 4 ₃ , 4 ₄
The light beams x ₃ and x ₄ are irradiated with a shift from each other by the amount that they are tilted to the left and right with respect to the optical axes x ₁ and x ₂ of the reflecting surfaces 4 ₁ and 4 ₂ .

Therefore, each of the above light distribution patterns 11 ₁ to 11 ₄
are combined to form one passing beam light distribution pattern 12.

In this way, in the case of the vehicle headlight 1,
The elements of the light distribution pattern are formed by the projection unit consisting of each reflector, light shield, and projection lens, and these elements are combined to obtain one light distribution pattern, so there is no loss of light or strain on the lens. , you can obtain your favorite light distribution pattern.

(F-2 Second Embodiment) [Figures 5 to 7] Figures 5 to 7 show the second embodiment of the vehicle headlamp of the present invention.
Example 1A is shown.

(a reflecting mirror) 13 is a reflecting mirror, and four reflecting mirrors 14 ₁ , 1
4 ₂ , 14 ₃ and 14 ₄ are integrally formed.

Each of the reflecting mirrors 14 ₁ to 14 ₄ is a reflecting surface 15 ₁ , 15 ₂ , 15 that forms a part of a parabola-ellipse composite surface, respectively.
_{3,154 .} Here, the parabola-ellipse composite surface refers to a surface that exhibits a parabola in horizontal cross-section and an ellipse in vertical cross-section.

The reflective surface 15 ₁ has a shape that is approximately the upper third of the parabolic-elliptic composite surface, and the reflective surface 15 ₂ has the shape that is approximately the lower third of the parabolic-elliptical composite surface.
₃ has the shape of approximately the left half of a parabola-ellipse composite surface, and the reflecting surface ₁₅₄ has the shape of approximately the right half of the parabola-ellipse composite surface.

The left edge of the reflecting mirror 14 ₁ and the upper edge of the reflecting mirror 14 ₃ are connected by the connecting part 16 ₁ , and the right edge of the reflecting mirror 14 ₁ and the upper edge of the reflecting mirror 14 ₄ are connected by the connecting part 16 ₂ . Therefore, the left side edge of the reflecting mirror 14 ₂ and the lower edge of the reflecting mirror 14 ₃ are connected by the connecting part 16 ₃ , and the right side edge of the reflecting mirror 14 ₂ and the lower edge of the reflecting mirror 14 ₄ are connected by the connecting part 16 ₄ . and are integrally connected to each other, thereby each reflecting mirror 1
A reflector 13 in which 4 ₁ to 14 ₄ are integrated is formed.

The reflecting surfaces 15 ₁ to 15 ₄ of the respective reflecting mirrors 14 ₁ to 14 ₄ have a common first focal point f ₀ . Also,
The optical axes of each of the reflective surfaces 15 ₁ to 15 ₄ extend in different directions. That is, the reflective surface 15
The optical axes x ₁ and x ₂ of the lenses ₁ and 15 ₂ are substantially coaxial and extend straight toward the front. Reflective surface 15
₃ is tilted to the left with respect to the optical axes x ₁ , x ₂ of the reflective surfaces 15 ₁ , 15 ₂ , and conversely, the optical axis x ₄ of the reflective surface 15 ₄ is tilted to the left with respect _to the optical axes x 1 , x 2 of the reflective surfaces _{15 1} , 15 _{2 .} It is leaning to the right.

f ₁ is the second focal line of the reflective surface 15 ₁ , f ₂ is the reflective surface 15 ₂
, f ₃ is the second focal line of the reflective surface 15 ₃ , and f ₄ is the second focal line of the reflective surface 15 ₄ . That is, since the reflecting surfaces 15 ₁ to 15 ₄ form part of a parabola-ellipse compound surface, the reflected light is focused at the second focal line position in the vertical direction, but the light is focused in the horizontal direction. Since the light beam is only parallel to the axis x, the light is focused on a line extending in the horizontal direction and perpendicular to the optical axis x at the second focal line position. The second focal lines f ₁ and f ₂ of the reflective surfaces 15 ₁ and 15 ₂ are located at approximately the same location.

Reference numeral 17 denotes a light source, for example, a filament of a light bulb, and is arranged at a position including the first focal point f ₀ .

Therefore, light is emitted from the light source 17, and each reflecting mirror 1
The light reflected by the reflecting surfaces 15 ₁ to 15 ₄ of _{4 1} to 14 ₄ is reflected from the second focal line f ₁ to 15 4 of each reflecting surface 15 ₁ to 15 ₄ .
Focus on f ₄ . However, although it is said that the light is focused, since the light source 17 is not a point but has a certain size, it is focused within a range that spreads horizontally in a band shape in a plane perpendicular to the optical axes x ₁ to x ₄ . It will shine.

(b Light-shielding bodies) 18 ₁ , 18 ₂ and 18 ₃ are light-shielding bodies, and the upper edges 19 ₁ , 19 ₂ and 19 ₃ are respectively light-shielding edges.
The light shielding body 18 ₁ has its light shielding edge 19 ₁ as the reflecting mirror 14 ₁ ,
Near the second focal lines f ₁ , f ₂ of 14 ₂ , their optical axes x ₁ ,
x ₂ from below, and its light-shielding edge 1
9 ₁ is the right side 19 from the center toward the reflector 13
₁ ′ is the sloped edge that slopes downward to the right. Light shielding body 18
The light-shielding edges 19 ₂ and 19 ₃ of ₂ and 18 ₃ extend horizontally, and the light-shielding body 18 ₂ has the light-shielding edges 19 ₂
The center of the optical axis is near the second focal line _f3 of the reflecting mirror ₁₄₃ .
x ₃ from below, and the light shielding body 18 ₃
is arranged such that the center of its light-shielding edge 19 ₃ is close to the second focal line f ₄ of the reflecting mirror 14 ₄ and in contact with the optical axis x ₄ from below.

_{Therefore , each} optical _{axis x 1 ,}
When viewed in a cross section perpendicular to x ₂ , x ₃ , x ₄ , they include reflective surfaces _{15 1} , 15 ₂ , whose lower sides are blocked by light shields 18 ₁ , 18 2 , 18 ₃ . 15 _3,1
The bundle of light reflected by 5 ₄ exists as an image.

(c projection lens) 20 ₁ , 20 ₂ and 20 ₃ are projection lenses,
20 ₁ is arranged in front of the center light shield 18 ₁ , 20 ₂ is arranged in front of the left light shield 18 ₂ , and 20 ₃ is arranged in front of the right light shield 18 ₃ .
Further, these projection lenses 20 ₁ to 20 ₃ have a convex lens shape, and the focal point F ₁ of the projection lens 20 ₁ is at the center of the light shielding edge 19 ₁ of the central light shield 18 ₁ , and the focal point F ₂ of the projection lens 20 ₂ is the light shielding edge 19 ₂ of the light shield 18 ₂
The focal point _F3 of the projection lens ₂₀₃ is at the center of the light shielding body 1.
They are respectively located at the center of the light-shielding edges 19 ₃ of 8 ₃ .

(d Light Distribution Pattern) Therefore, in the case of the above-mentioned automobile headlamp 1A, a passing beam is emitted according to the light distribution pattern described below.

The light reflected by the reflecting surfaces 15 ₁ and 15 ₂ of the reflecting mirrors 14 ₁ and 14 ₂ has an image whose lower edge is limited by the light shield 18 ₁ and is projected forward as an upside-down image by the projection lens 20 ₁ . Since the light is projected onto the light beam, it is irradiated by light distribution patterns 21 ₁ and 21 ₂ shown in FIG.

In addition, the reflecting surfaces 15 ₃ and 1 of the reflecting mirrors 14 ₃ and 14 ₄
The light reflected by 5 ₄ passes through the light shielding bodies 18 ₂ , 18 ₃
The image whose lower edge is limited by the projection lens 20 ₂ ,
20 ₃ is projected forward as an upside-down image,
In addition, since the optical axes x ₃ and x ₄ of the reflecting mirrors 14 ₃ and 14 ₄ are tilted to the left or right with respect to the optical axes x ₁ and x ₂ of the central reflecting mirrors 14 ₁ and 14 ₂ , respectively, Light distribution patterns 21 ₃ and 21 ₄ shifted to the right are shown.

Therefore, each of the above light distribution patterns 21 ₁ to 21 ₄
are combined to form one passing beam light distribution pattern 22.

In the automobile headlamp 1A according to the second embodiment, the elements of the light distribution pattern are formed by a projection unit consisting of each reflecting mirror, a light shield, and a projection lens, and these elements are synthesized. Since a desired light distribution pattern can be obtained, a desired light distribution pattern can be obtained without any loss of light or strain on the lens.

(G Effect of the Invention) As is clear from the above description, the vehicle headlight of the present invention includes a plurality of reflecting mirrors each having a reflecting surface having a first focal point and a second focal region, such as an ellipsoidal surface. A light shielding body is arranged so that the first focal point is common and each optical axis extends in different directions, a light source is arranged at the first focal point, and a light shielding edge is located near the second focal point of each reflecting mirror. In front of each light shield, a projection lens whose focal range is located approximately on the light shielding edge of the corresponding light shield is placed, and each of the projection lenses allows the projection lens to be positioned in the vicinity of the light shielding edge of the corresponding light shield. It is characterized in that the image and the light not blocked by these light-blocking edges are projected forward.

Therefore, according to the vehicle headlamp of the present invention, a plurality of partial light distribution patterns projected by a plurality of projection units each comprising a common light source, a separate reflecting mirror, a light shielding body, and a projection lens are provided. Since a - light distribution pattern is obtained by combining, a desired light distribution can be obtained extremely easily, and waste of light can be eliminated.

In the present invention, the optical axes of the respective reflecting mirrors do not have to be shifted in the same plane, but may be shifted in the vertical direction or in both the vertical and horizontal directions.

[Brief explanation of drawings]

Figures 1 to 4 show the first part of the vehicle headlamp of the present invention.
FIG. 1 is a schematic perspective view of the embodiment.
Figure 2 is a schematic plan view, Figure 3 is a front view of the reflecting mirror,
FIG. 4 is a light distribution pattern diagram, and FIGS. 5 to 7 show a second embodiment of the vehicle headlamp of the present invention.
Fig. 5 is a schematic perspective view, Fig. 6 is a schematic plan view, and Fig. 7 is a schematic perspective view.
The figure is a light distribution pattern diagram, and FIG. 8 is a schematic perspective view showing an example of a conventional vehicle headlamp. Explanation of symbols, 1...Vehicle headlight, 3 ₁ , 3 ₂ ,
3 ₃ , 3 ₄ ... Reflecting mirror, 4 ₁ , 4 ₂ , 4 ₃ , 4 ₄ ... Reflecting surface, 6 ... Light source, 8 ₁ , 8 ₂ , 8 ₃ ... Light shielding body,
9 ₁ , 9 ₂ , 9 ₃ ...shading edge, 10 ₁ , 10 ₂ , 10 ₃
...Projection lens, 1A...Vehicle headlight, 14 ₁ ,
14 ₂ , 14 ₃ , 14 ₄ ...Reflector, 15 ₁ , 15 ₂ ,
15 ₃ , 15 ₄ ... reflective surface, 17 ... light source, 18 ₁ ,
18 ₂ , 18 ₃ ... light shielding body, 19 ₁ , 19 ₂ , 19 ₃ ...
...shading edge, 20 ₁ , 20 ₂ , 20 ₃ ... projection lens,
f ₀ ... first focal point, f ₁ , f ₂ , f ₃ , f ₄ ... second focal point of the reflecting mirror
Focal range, x ₁ , x ₂ , x ₃ , x ₄ ...Optical axis of reflecting mirror, F ₁ ,
F ₂ , F ₃ ... Focal range of the projection lens.

Claims (1)

[Claims] 1. A plurality of reflecting mirrors each having a reflecting surface having a first focal point and a second focal region, such as an ellipsoidal surface, each having a common first focal point, and each optical axis extending in a different direction. A light source is placed at the first focal point, a light shield whose light shielding edge is located near the second focal region of each reflecting mirror is placed, and a light shield whose focal region corresponds to the light shield is placed in front of each light shield. Projection lenses are arranged approximately on the light-shielding edges, and each projection lens projects forward an image near the light-shielding edge of the corresponding light-shielding body and light that is not blocked by these light-shielding edges. A vehicle headlamp characterized by: