JPH08222012A - Vehicle mirror reflector and method of forming the same - Google Patents

Abstract

(57) [Abstract] [Purpose] The use efficiency of light is improved by reducing the area of the peripheral wall portion formed on the upper and lower sides and / or the left and right sides of the reflection area of the reflecting mirror of the vehicular lamp. [Structure] First, an outer frame 1 that defines a front surface of a reflecting surface.
Is set, and reference parabolas 2 and 3 are set in the horizontal plane and the vertical plane including the optical axis of the reflecting mirror, and based on the reference parabola 3, a parabola group including a large number of parabolas having different focal lengths is set. Then, a spline curve 5 connecting the vertices of the multiple reflection line 4 formed by partially connecting parabolas belonging to the parabola group along the direction orthogonal to the common axis of the parabola group is formed, A basic surface 8 is formed from the parabola 2, the outer frame 1, and the spline curve 5. A paraboloid of revolution 9 group consisting of a number of paraboloids of revolution having different focal lengths is set, and a group of intersecting lines which is the intersection of the basic plane 8 and the paraboloid of revolution 9 is determined before adjoining. A large number of reflection steps 12 are formed along the intersecting line group by partially allocating the paraboloids of revolution between the intersecting lines.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reduces the area of peripheral wall portions formed above and / or to the left and right of a reflection area of a reflecting mirror of a vehicular lamp so as to ideally reduce to zero. It is intended to provide a novel reflector for a vehicular lamp and a method for forming the same, which enables efficient use of the above.

[0002]

2. Description of the Related Art Reflecting mirrors for vehicular lamps include a reflecting mirror which is provided separately from the lamp body and which is provided by applying a reflection treatment to the inner surface of the lamp body. Those that form a surface are known. In the latter case, the reflecting mirror has a single reflecting surface in the form of a paraboloid of revolution or a so-called multiple reflecting surface consisting of a number of reflecting steps, etc. It is formed in the shape of an open box.

For example, in a reflecting mirror a shown in FIG. 15, a part of a lamp body b is an effective reflecting portion c having a paraboloidal shape, and the upper, lower, left and right sides thereof are flat peripheral wall portions d, d, respectively.・
・ ・ Surrounded by

[0004]

By the way, in the above-mentioned lamp, since the light reflected from the peripheral wall portion of the light emitted from the light source becomes unplanned light and is not effectively utilized, the utilization efficiency of the luminous flux is improved. There is a problem that it is difficult to raise.

That is, as shown in FIG. 16, among the lights emitted from the light source e located in the lamp space of the lamp body b, the lights 1, 1, ... When the light becomes an upward light, it causes a dazzling effect on a driver of an oncoming vehicle.

In particular, when the reflecting surface is a paraboloid of revolution or when it is constituted by a plurality of reflecting steps forming a part of the paraboloid of revolution, the vertical width H and the lateral width of the lamp body b are If W is different, the length in the irradiation direction of the peripheral wall portion that defines the narrower width becomes longer, and the amount of light wasted on the peripheral wall portion increases. For example, when the vertical width H is narrower than the horizontal width W, the length D in the irradiation direction of the peripheral wall portions located above and below the reflecting portion c becomes large, so the solid angle ω when the effective reflecting portion c is seen from the light source is There is a limit to how large it can be.

[0007]

Therefore, in order to solve the above-mentioned problems, the reflecting mirror of the vehicular lamp of the present invention has a plurality of rotating frames having different reflecting surfaces with an outer frame of a reflecting surface in one plane. A large number of rotating paraboloids are partially assigned between the intersecting lines that are adjacent to each other along the intersecting line group obtained as the intersection of the parabolic rotating parabolic group and the reflecting basic surface. A reflecting mirror for a vehicle lamp having a reflecting surface on which a reflecting step is formed, the reflecting mirror extending in a vertical direction and having end points along an intersection line located on the upper and lower frames and / or the left and right frames of the outer frame of the reflecting mirror. The step is formed.

Further, a method of forming a reflecting mirror of a vehicular lamp according to the present invention is to form the above reflecting mirror by the following steps (1) to (8).

(1) An outer frame defining the front shape of the reflecting surface is set.

(2) A reference parabola is set in a horizontal plane and a vertical plane including the optical axis of the reflecting mirror.

(3) A parabola group consisting of a large number of parabolas having different focal lengths is set with respect to the reference parabola of (2),
A parabola belonging to the parabola group is partially connected along a direction orthogonal to the common axis of the parabola group to form a complex curve.

(4) A spline curve connecting the vertices of the compound curve of (3) is formed.

(5) A basic surface of the reflecting surface is formed based on the outer frame, the spline curve of (4) and / or the reference parabola of (2).

(6) Set a paraboloid of revolution consisting of a large number of paraboloids of revolution having different focal lengths.

(7) The intersection line group is determined as the intersection of the basic surface and the paraboloid of revolution.

(8) A large number of reflection steps are formed along the intersecting line group by partially allocating the paraboloid of revolution between adjacent intersecting lines.

[0017]

According to the present invention, a spline connecting the vertices of a compound curve obtained by setting a contour frame defining the front shape of the reflecting surface and using a parabola group set based on the reference parabola. By forming a curved line and forming a basic surface of the reflecting surface based on this and the outline frame and the spline curve, it is possible to prevent a flat portion from being formed at the peripheral edge of the reflecting surface, and to form the basic surface and the paraboloid of revolution. After deciding the intersection line group between the intersection lines, by partially allocating the paraboloids of revolution between the adjacent intersection lines respectively, the endpoints extend in the vertical direction and the end points are the upper and lower frames and / or the left and right sides of the outer frame of the reflecting mirror. Since the reflection step is formed along the line of intersection located on the frame, it is possible to reduce the ineffective reflection area in the peripheral wall portion of the reflecting mirror.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A reflecting mirror of a vehicular lamp of the present invention and a method of forming the same will be described below with reference to the illustrated embodiments.

The reflecting mirror according to the present invention is such that the inner area of the peripheral wall portion in the vertical and / or horizontal direction is reduced to increase the solid angle of the reflecting surface seen from the light source.

First, regarding the shape design of the reflecting mirror, it is divided into two steps, that is, a step of forming a basic surface which is a basis of the reflecting surface and a step of forming a reflecting step on the basic surface.
3 will be described.

1 to 7 show a procedure for forming a basic surface. In FIGS. 1 to 3, an axis extending in the front-rear direction through the center of the reflecting surface is an x-axis, and an axis extending in the horizontal and vertical directions orthogonal to the x-axis is an y-axis and a z-axis are orthogonal to each other. The coordinate system is set.

(A1) Set the outer frame of the reflecting surface.

First, as shown in FIG. 1, an outer frame 1 which is the outer shape of the reflecting surface when viewed from the front (when viewed from the x-axis direction) is determined. The outer frame 1 has a horizontally long rectangular shape in the present embodiment, but any shape may be used as long as it is in a plane. In addition, the point A in the figure is the outer frame 1
The middle point of the upper side (the point located above the intersection of the outer frame 1 and the x-z plane), the point B is the middle point of the left side of the outer frame 1 (of the intersection of the outer frame 1 and the xy plane). Of these, the point is located on the left when viewed from the front).

(A2) The depth of the reflecting surface is determined.

That is, as shown in FIG. 2, the length L of the reflecting surface in the x-axis direction is determined.

(A3) A reference parabola of the focus Fs passing through the point A is drawn in the vertical plane.

As shown in FIG. 2, a reference parabola 2 passing through the point A and having the point Fs as a focal point is set in a vertical plane passing through the point A.

(A4) A reference parabola of the focus Fs passing through the point B is drawn in the horizontal plane.

As shown in FIG. 3, a reference parabola 3 passing through the point B and having the point Fs as a focal point is set in a horizontal plane passing through the point B.

(A5) A "multiple reflection line" is formed based on the reference parabola 3.

The "multiple reflection line" defined here means
It is a compound curve formed by using a parabola group consisting of a plurality of parabola having different focal lengths and sequentially connecting some of the parabola belonging to the parabola group according to a predetermined rule.

FIG. 5 illustrates a method of forming multiple reflection lines, and each parabola p forming a parabola group.
For ar_i (i = 1, 2, ...), the focus F is shared, and the respective focal lengths f_i (i = 1, 2,
...) are different from each other. The above-mentioned reference parabola 3 is used as a reference line when a parabola group is generated.

The Y axis shown in the drawing extends in a direction orthogonal to the common axis AA of the parabola group passing through the focal point F, and the point S on the parabola par_1 located closest to the focal point F undergoes multiple reflection. The first change point of the line is shown. That is, the curved portion in the range Ys of the parabola par_1 becomes the first element of the multiple reflection line.

Then, the step width ΔY along the Y-axis direction
Therefore, each parabola par_i (i = 2, 3, ...) Is partially connected one after another. In the figure, “Δf” indicates the amount of change in the focal length, and the outer parabola has a larger focal length. Further, when connecting the parabolas, it is set so that the boundary line between the adjacent parabolas lies on a straight line passing through the focal point F.

Thus, the four parameters f_1,
The multiple reflection line 4 is formed as a multi-node compound curve in which the parabola group is partially connected by controlling the shape and connection of the curve by Δf, Ys, and ΔY. In this example, the parabola group has a common focus, but in general, the actual light source is not a point light source but always has a certain range, so the focus of the parabola group is distributed over a certain range. be able to.

(A6) Draw a spline curve passing through each vertex of the multiple reflection line 4.

As is apparent from the above forming method, the multiple reflection line 4 is a compound curve having a plurality of irregularities, and based on this, a multiple curve is obtained as shown by the broken line in FIG. 6 in order to obtain a smooth curve. Each vertex V_i (i =
1, 2, ...) to form a spline curve 5.

(A7) A basic surface is formed based on the outer frame 1 and the spline curve 5.

The vertical width in the vertical direction of the reference parabola 2 in (a3) above is defined by the upper and lower frames of the outer frame 1, and the multiple reflection line 4 and the left and right frames of the outer frame 1 in (a5). Thus, the curves 6, 7 as shown in FIG.
Can be obtained. That is, the curve 6 is a spline curve that passes through the upper left point P1 and the lower left point P2 of the outer frame 1, and the left end point of the spline curve 5, and the curve 7 is the upper right point P3 and the lower right point P4 of the outer frame 1. , And spline curve 5
Is a spline curve that passes through the right end point of. A basic surface can be formed by generating a spline curved surface from these curves 6 and 7, the reference parabola 2 and the spline curve 5.

FIG. 7A shows a case where the left and right end points of the spline curve 5 and the four corner points of the outer frame 1 are not on the same straight line. Although a flat portion will be generated, the end points of the spline curve can be positioned on the left and right frame lines of the outer frame 1 as shown in FIG. 7B. That is, the end points of the spline curve 5'can be placed on the multiple reflection line by setting the reference parabola and selecting the formation parameters of the multiple reflection line.

In the above description, the reference parabola 2 in the vertical direction is left as it is. However, in some cases, multiple reflection lines are formed with respect to the reference parabola 2 and each vertex of the multiple reflection line is formed. It is needless to say that a spline curve connecting the two can be obtained, and the basic surface can be formed based on the spline curve in the horizontal direction and the outer frame 1.

Next, the procedure for forming the reflection step on the above-mentioned basic surface will be described with reference to FIGS.

(B1) Set the basic surface.

The basic surface 8 designed by the above procedure is shown in FIG.
Set as shown in.

(B2) Setting of paraboloids of rotation.

Next, as shown in FIG. 9, a paraboloid of revolution group 9 which defines the light distribution performance of the reflecting surface is prepared. The group of rotational paraboloids 9 has a common axis of rotational symmetry and has different focal lengths (the focal positions are not always the same), and includes a large number of rotational paraboloids 9a, 9a ,. ing. The paraboloids of rotation 9a, 9a, ... Are selected so that they do not spatially intersect.

(B3) Generation of intersecting line group.

Then, as shown in FIG. 10, the lines of intersection 10, 10, ... Between the basic surface 8 and the paraboloid of revolution 9 are determined. The intersecting lines 10, 10, ... Do not intersect each other.

FIG. 11 shows the basic plane 8 for forming the intersection line 10.
Of the optical path L with respect to the point P on the basic surface 8. In the figure, a vector "V_IN" is a direction vector of an incident light beam emitted from a focal point of a certain paraboloid of revolution 9a and directed to a point P, and a vector "V_OUT" is a point P.
And the direction vector of the reflected light ray at each point, and "R" indicates the minute reflection surface at the point P on the basic surface 8,
In addition, the vector “N_R” is the minute reflection surface R at the point P.
Is a normal vector, "T" is a tangent plane at a point P of the basic surface 8, and a vector "N_T" is a tangent plane T at a point P.
The normal vectors set up are shown.

The vector W is the normal vectors N_R and N_
The cross product 10 with T and the intersecting line 10 indicated by a broken line is the cross product W
Can be obtained as a spline curve by giving as a tangent vector at an arbitrary point P.

(B4) Formation of reflection step.

When the intersection lines 10, 10, ... Are determined,
The reflection step is formed according to these. That is, FIG.
As shown in, the reflection step 11, by partially embedding the paraboloid of revolution 9 in the space between the adjacent intersecting lines,
11 are formed. In FIG. 13, the front view of the curved surface is arranged in the upper stage, and the schematic view of the cross-sectional shape when cut along the line BB of the front view is arranged in the lower stage. The intersection lines on the curved surface are 10a in order from the one close to the center 12 of the intersection line group,
10b, 10c, ..., These appear as boundaries of reflection steps. The broken line in the figure indicates the paraboloid of revolution 9, and the reflection step 11a indicates the intersection line 10.
It is said that the reflection step 11b is formed in the inner area defined by a, the reflection step 11b is formed in the inner area between the intersection lines 10a and 10b, and the reflection step 11c is formed in the inner area between the intersection lines 10b and 10c. The shape of the reflection step is specified. That is, the individual step surfaces are formed so as to form a part of a paraboloid of revolution having different focal lengths, and are formed stepwise when viewed in cross section.

As described above, when a reflecting surface having a reflecting step formed along a group of multiple intersecting lines and a reflecting mirror having the reflecting surface are created using a CAD system, the reflecting mirror is based on this. It is possible to obtain the CAM data for making the mold.

FIG. 14 is a front view showing the geometrical characteristics of the reflecting surface formed by the above method, showing the arrangement of the intersecting line group 13 on the curved surface.

As shown, the intersection lines 13a, 13a ,.
.. are arranged in vertical stripes, and intersecting line group 1
Reference numeral 3 includes a line of intersection curved outward in the left-right direction and a line of intersection curved inward in the opposite direction. That is, the intersecting lines 13b, 13b at the central portion of the reflecting surface (the inner region (indicated by diagonal lines in the figure) has a paraboloid of revolution).
Is curved in a convex shape toward the outside, and the intersecting lines located on both left and right sides thereof are curved in a convex shape toward the inside. The curve of the line of intersection is small in the middle of the curved surface, and there is a tendency that the line of intersection gradually curves toward both ends. It should be noted that it is clear from the way of forming the reflecting surface that the end points of these intersecting lines are located on the outer frame.

However, as is apparent from the above-described method of forming the reflection surface, multiple reflection lines are set in the horizontal plane and / or the vertical plane, and the end points of the spline curve passing through the respective vertices of the multiple reflection line are contoured. By placing the reflection step along the intersecting line group on the curved surface obtained based on the spline curve, the outline frame, and the reference parabola so as to be placed on the upper and lower frames and / or the left and right frames of the frame, By reducing the ineffective reflection area, it is possible to increase the solid angle in which the reflection surface is seen from the center of the light source, and to improve the utilization efficiency of the light flux.

[0057]

As is apparent from the above description, according to the reflecting mirror of the vehicular lamp and the method for forming the same of the present invention, first, the outer frame for defining the front shape of the reflecting surface is set, A complex curve formed using a parabola group set based on a reference parabola is used to form a spline curve connecting each vertex of the parabola, and the basic surface of the reflecting surface is formed based on this and the outline frame and the reference parabola. Then, by determining the intersecting line group that is the intersection of the basic surface and the paraboloid of revolution, and by partially allocating the paraboloid of revolution between adjacent intersecting lines, respectively, it is possible to extend in the vertical direction and Since the reflection step can be formed along the intersection line whose end points are located on the upper and lower frames and / or the left and right frames of the outer frame of the reflecting mirror, the effective reflection area on the peripheral wall of the reflecting mirror can be reduced and the reflection from the light source can be reduced. Enlarging the solid angle to see the surface It can be.

[Brief description of drawings]

FIG. 1 is a view for explaining formation of a basic surface of a reflecting surface according to the present invention together with FIGS. 2 to 7, and this drawing is a front view showing an outer frame.

FIG. 2 is a side view showing a reference parabola set in the vertical direction.

FIG. 3 is a bottom view showing a reference parabola set in the horizontal direction.

FIG. 4 is a perspective view showing an outer frame and a reference parabola.

FIG. 5 is a diagram for explaining formation of multiple reflection lines.

FIG. 6 is a diagram showing how to form a spline curve for multiple reflection lines.

FIG. 7 shows a curved surface formed based on an outer frame, a reference parabola, and a spline curve. (A) shows the case where the end of the spline curve is not placed on the outer frame, (b).
Shows the case where the end of the spline curve is placed on the outer frame.

FIG. 8 is a view for explaining the method for forming a reflecting surface according to the present invention, together with FIGS. 9 to 13, and this drawing is a view showing a basic surface.

FIG. 9 is a diagram showing a group of rotary paraboloids.

FIG. 10 is a diagram showing a line of intersection obtained as a line of intersection between the paraboloid of revolution and the basic surface.

FIG. 11 is a perspective view for explaining formation of intersecting lines.

FIG. 12 is a diagram for explaining formation of reflection steps along a group of intersecting lines.

FIG. 13 is a diagram showing a front shape and a cross-sectional shape of a reflection step.

FIG. 14 is a front view showing an example of an arrangement of intersecting lines of reflecting surfaces.

FIG. 15 is a perspective view showing a configuration of a conventional reflecting mirror.

FIG. 16 is a diagram for explaining a conventional problem.

[Explanation of symbols]

 1 outline frame 2, 3 reference parabola 4 multiple reflection line (composite curve) 5 spline curve 8 basic surface 9 rotational parabolic surface group 9a rotational parabolic surface 10 intersection line 12 reflection step 13 intersection line group par_i (i = 1, 2 , ...) Parabolic group

Claims (2)

[Claims] 1. An intersection line obtained by intersecting a basic surface of a reflective surface with a group of rotational parabolic surfaces having a large number of rotational parabolic surfaces having different focal lengths, the outer frame of the reflective surface being in one plane. A reflecting mirror of a vehicle lamp having a reflecting surface in which a large number of reflecting steps are formed by partially allocating respective paraboloids of revolution between adjacent intersecting lines along a group, the reflecting mirror extending in the vertical direction. A reflecting mirror of a vehicular lamp, wherein a reflecting step is formed along an intersection line whose end points are located on the upper and lower frames and / or the left and right frames of the outer frame of the reflecting mirror. 2. A method of forming a reflector of a vehicle lamp according to claim 1, wherein (1) an outer frame defining a front shape of the reflector is set, and (2) an optical axis of the reflector is set. A reference parabola is set in the horizontal plane and the vertical plane containing the parabola, and (3) a parabola group consisting of a large number of parabolas having different focal lengths is set for the reference parabola in (2), and the parabola belonging to the parabola group is set. Form a compound curve formed by connecting parts along a direction orthogonal to the common axis of
(4) Forming a spline curve connecting the vertices of the composite curve of (3), and defining the basic surface of the reflecting surface based on the outline frame of (5), the spline curve of (4) and / or the reference parabola of (2). After the formation, (6) set a paraboloid of revolution consisting of a large number of paraboloids of revolution with different focal lengths, and (7) determine a group of intersecting lines as an intersection of the basic surface and the paraboloid of revolution. And (8) a plurality of reflection steps are formed along the intersection line group by partially allocating the paraboloid of revolution between the adjacent intersection lines, respectively. Method of forming reflector.