JPH0760613B2 - High efficiency vehicle lighting - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp, such as a tail lamp / braking lamp, which requires parallel rays to be incident on a lens in a relatively large area. The present invention relates to the improvement of the luminous flux utilization rate.

[0002]

2. Description of the Related Art FIG. 2 shows an example of the structure of a conventional vehicle lamp 90 of this type, and a light source 9 is used as a reflecting mirror 91.
A paraboloid of revolution having a focal point at 2 is adopted, whereby light from the light source 92 reflected by the reflecting mirror 91 is made to enter the lens 93 as parallel rays. At this time, if it is assumed that the light source 92 uniformly emits light in all directions, the solid angle at which the reflecting mirror is seen from the light source 92 is divided by the total solid angle. Utilization rate.

[0003]

In the vehicular lamp 90 having the above-mentioned conventional structure, when the lens 93 is required to have a relatively large light emitting area, the reflection is accompanied by the enlargement of the area of the lens 93. The mirror 91 also becomes large in size, and when the focal length is kept constant, the depth also greatly increases and it becomes difficult to mount the mirror 91 on the vehicle. By extending the focal length of the reflecting mirror 91, the depth of the entire reflecting mirror 91 increases. It is supposed to be reduced and dealt with.

However, the fact that the depth of the reflecting mirror 91 is reduced means that the solid angle seen from the light source 92 is reduced, and the luminous flux utilization rate is lowered. For this reason, this type of lens having a relatively large light emitting area is used. In the vehicular lamp 90 that employs 93, there is a problem that a bright lamp cannot be obtained for the power consumption of the light source 92, and a solution to this problem has been a problem.

[0005]

The present invention, as a concrete means for solving the above-mentioned conventional problems, is provided behind the light source so that the reflection direction is the front, and is horizontal with respect to the vertical section with respect to the lamp mounting direction. A first reflecting surface having an elliptical reflecting surface having the light source as a first focal point is formed on at least one of the cross sections, and the first reflecting surface is covered from the front except the optical path of the reflected light from the first reflecting surface. A second reflecting surface having a concave spherical surface centered on the light source, a third reflecting surface provided in the optical path of the reflected light from the first reflecting surface and diffusing and reflecting the reflected light substantially rearward, And a fourth reflecting surface which is provided in front of the second reflecting surface and substantially behind the third reflecting surface and which reflects light from the third reflecting surface as parallel rays in the irradiation direction. To solve the problem by providing a highly efficient vehicular lamp Than it is.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail based on an embodiment shown in the drawings. Reference numeral 1 in FIG. 1 denotes a vehicle lamp according to the present invention. The vehicle lamp 1 is a conventional example in that light from a light source 2 is incident on a lens 4 as parallel rays by a reflecting mirror 3. However, according to the present invention, the reflecting mirror 3 includes a first reflecting surface 31, a second reflecting surface 3
2, the third reflecting surface 33 and the fourth reflecting surface 34. It should be noted that, for ease of understanding, the drawings are shown in an exaggerated state of essential parts such as the first reflecting surface 31 and the second reflecting surface 32, and the dimensional ratios of the respective parts in actual implementation do not necessarily match. Not a thing.

The structure of the reflecting mirror 3 will be described in more detail below. First, the first reflecting surface 31 has the first focus of the light source 2 on a horizontal cross section in the mounted state of the vehicle lamp 1, for example. An elliptic cylindrical surface having an elliptic surface defined as F1 or a parabolic elliptic surface having a similar elliptical surface to the horizontal section and a parabolic surface to the vertical section, or a compound having an elliptic surface for both horizontal and vertical sections. A reflecting surface having an elliptical reflecting surface having the light source 2 as a first focal point is formed on at least one of a vertical section and a horizontal section, such as an elliptical surface and a spheroidal surface (hereinafter, this is represented by a spheroidal surface in this embodiment. Let me explain)
The light source 2 is provided behind the light source 2 so that the reflection direction thereof substantially coincides with the irradiation direction of the vehicular lamp 1.

The second reflecting surface 32 has a reflecting surface as the light source 2.
Is provided so as to cover the opening 31a on the front surface of the first reflection surface 31 as a concave spherical surface centered at, and if the first reflection surface 31 is a spheroid at this time, this first reflection surface A circular hole 32a is provided in the corresponding portion of the second reflecting surface 32 so as not to obstruct the optical path of the beam light that converges from the surface 31 to the second focus F2.

The third reflecting surface 33 is the first reflecting surface 3
It is installed in the optical path of the beam light from 1. At this time, the reflection surface shape of the third reflection surface 33 is a convex surface having different curvatures in the vertical direction and the horizontal direction, or a convex surface having the same curvature. The light beam from the first reflecting surface 31 is appropriately diffused rearward so as to reach the entire surface of the fourth reflecting surface 34, which will be described later. The third reflecting surface 33 is not limited to the front of the second focus F2 as shown in FIG. 1, but may be provided behind the second focus F2.

The fourth reflecting surface 34 is formed to have an area and a shape sufficient to cause the entire surface of the lens 4 to emit light. At this time, the fourth reflecting surface 34 is formed into the third reflecting surface 33. It is formed as a concave reflecting surface that is a curved surface that allows the reflected light from the above to enter the lens 4 as parallel light heading in the irradiation direction of the vehicular lamp 1.

Next, the operation and effect of the vehicular lamp 1 of the present invention having the above-described structure will be described. The first reflecting surface 31 converges the contact light from the light source 2 toward the second focal point F2. It is emitted forward as a beam of light, but at this time,
Since the opening 31a of the first reflecting surface 31 is covered with the light source 2, that is, the second reflecting surface 32 which is a concave spherical surface having the first focal point F1 as the center, the light that abuts on the second reflecting surface 32 is also included. Almost all of the light rays that are returned to the first focal point F1 and are emitted from the light source 2 become beam light that is directed to the second focal point F2.

The light beam converged with high efficiency as described above is diffused by the third reflecting surface 33 and converted into parallel rays by the fourth reflecting surface 34. At this time, for example, the fourth reflecting surface is reflected. If the shape of the surface 34 is circular, a convex spherical shape or a conical shape is selected as the shape of the third reflecting surface 33. For example, the light beam from the second reflecting surface 32 is directed to the fourth reflecting surface 3.
Since it is designed to diffuse corresponding to the shape of 4,
As a result, the light beam from the light source 2 is incident on the lens 4 as a parallel light beam without being lost.

[0013]

As described above, according to the present invention, an elliptical first reflection surface having an opening covered with a second reflection surface of a concave spherical surface centered on the light source and having a first focus set on the same light source is provided. By providing almost all of the light from the light source as a beam of light directed to the second focal point, a third reflecting surface for diffusing corresponding to the shape of the fourth reflecting surface is installed in the beam of light, and the fourth reflecting surface is provided. In the vehicular lamp of this type, which is made to have a relatively large area, almost all of the light from the light source is finally made into effective irradiation light by making the vehicular lamp into a lens as parallel light. In addition, there is little glare in the light source, and an excellent effect is provided that makes it possible to provide a bright lamp without lowering the luminous flux utilization rate.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a highly efficient vehicular lamp according to the present invention.

FIG. 2 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 ... Vehicle lamp 2 ... Light source 3 ... Reflecting mirror 31 ... First reflecting surface 31a ... Aperture 32 ... Second reflecting surface 32a ... Circular hole 33 ... Third reflecting surface 34 ... Third Four reflection surfaces 4 …… Lens F1 …… First focus F2 …… Second focus

Claims (1)

[Claims] 1. A elliptical reflecting surface having a first focus on the light source is formed on at least one of a vertical cross section and a horizontal cross section provided behind the light source so that the reflection direction is the front. A reflection surface, a second reflection surface of a concave spherical surface that covers the first reflection surface from the front except the optical path of the reflected light from the first reflection surface and has the light source as a center, and reflection from the first reflection surface A third reflecting surface provided in the optical path of the light for diffusing and reflecting the reflected light substantially rearward, and a third reflecting surface provided in front of the second reflecting surface and substantially behind the third reflecting surface. A highly efficient vehicular lamp having a reflecting surface formed of a fourth reflecting surface that reflects light from the light source as parallel rays in the irradiation direction.