JPH05120903A - Reflecting mirror of lighting fixture for vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] In a conventional reflector for a vehicle lamp, since the reflector is formed of a steel plate, the accuracy is reduced due to springback during formation, and the reflection by aluminum vapor deposition is also caused. This has led to an increase in cost due to the complexity of the production process such as the formation of the film and the accompanying undercoat and topcoat construction. According to the present invention, the reflecting mirror 1 has a substantially bowl-shaped reflector 2 made of a transparent member, and an inner surface 2a of the reflector 2 is formed.
Alternatively, the prism cuts 21 and 22 formed on the outer surface 2b or both surfaces and the total reflection occurring on the contact surface between the transparent member and the atmosphere make the emitted light from the light source 10 a parallel light beam in a predetermined direction. By using a reflecting mirror, the reflecting mirror 1 can be left as it is in the molded state of the resin member, and it is possible to improve the accuracy and reduce the cost at the same time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp, and more particularly to a reflecting mirror used to give the vehicular lamp a light distribution characteristic in a predetermined direction.

[0002]

2. Description of the Related Art An example of a conventional reflecting mirror 90 of this type is shown in FIG. 4. For example, a rotating paraboloidal reflector 91 which focuses on the position of the light source 10 is formed by means such as press forming of a steel plate. The reflector 91 is formed by forming a reflecting film 92 by aluminum vapor deposition on the inner surface side of the reflector 91, and the light emitted from the light source 10 in all directions is formed by the reflector 90. It converges as a parallel light beam in the optical axis (= rotational axis) Z direction and enables the light to reach far.

[0003]

However, in the above-mentioned conventional reflecting mirror 90, at the time of press forming which is a manufacturing process of the reflector 91, the elasticity of the steel sheet will restore the shape of the mold to the state before forming. It is unavoidable that so-called springback occurs, and it is difficult to obtain an accurate paraboloid of revolution, resulting in a problem of reduced accuracy. Further, when the reflective film 92 is formed, it is smooth. It is necessary to previously form an undercoat film 93 on the inner surface of the reflector 91 in order to obtain a transparent reflection film 92.
Furthermore, in order to improve the weather resistance of the reflective film 92, the top coat film 94 is also required, which causes a problem that the production process becomes complicated, and it is a problem to solve these problems. Was becoming.

[0004]

As a concrete means for solving the above-mentioned conventional problems, the present invention provides a reflecting mirror of a vehicular lamp for reflecting emitted light from a light source as parallel rays in a predetermined direction, The reflecting mirror forms a reflector in a substantially bowl shape with a transparent member, and a prism cut formed on an inner surface or an outer surface of the reflector or both surfaces thereof,
Providing a reflecting mirror for a vehicle lamp characterized in that emitted light from the light source is a parallel light beam in a predetermined direction by total reflection occurring on the contact surface between the transparent member and the atmosphere, thereby improving product accuracy. By improving and simplifying the production process, any of the above-mentioned conventional problems can be solved.

[0005]

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 is a reflecting mirror according to the present invention, and this reflecting mirror 1 is similar to the conventional example in that the emitted light from the light source 10 is a parallel light traveling in the irradiation direction X. However, according to the present invention, the reflector 2 of the reflecting mirror 1 is formed of a transparent member such as resin, and the contact (caused by the difference in refractive index between the member on which the reflector 2 is formed and the atmosphere ( It is said that the parallel rays described above are obtained by total reflection on the (boundary) surface.

Here, the reflector 2 will be described in more detail. The reflector 2 is formed in a substantially bowl shape so as to cover the light source 10 from the rear, but the shape thereof is a conventional example. The present invention is not particularly limited to the paraboloid of revolution or the plane of revolution, and the reflector 2 may be applied in the irradiation direction X.
The front view shape when viewed from above may be, for example, an ellipse.

In addition, the reflector 2 is provided with an inner surface prism cut 21 on the inner surface 2a side and an outer surface prism cut 22 on the outer surface 2b side as required.
It is supposed that the light from the light source 10 is refracted mainly on the inner surface 2a side of the reflector 2 and the total reflection is performed on the outer surface 2b side to obtain parallel rays.

2 and 3 show more concretely an example of the above-described structure. First, the one shown in FIG. 2 is an inner surface prism cut 21 only on the inner surface 2a side of the reflector 2.
As shown in the figure, the light from the light source 10 is first refracted at an angle at which the light is totally reflected with respect to the outer surface 2b when passing through the incident surface 21a of the inner surface prism cut 21 and the reflector 2 is reflected. It is introduced into the transparent member (refractive index <1) that constitutes it, and total reflection occurs in the transparent member due to the difference in refractive index between the outer surface 2b and the atmosphere (refractive index = 1), and again,
It returns to the inner surface 2a side, reaches the exit surface 21b of the inner surface prism cut 21, and the irradiation direction X is reached at this exit surface 21b.
The light is refracted in parallel with and is emitted from the reflector 2.

On the other hand, FIG. 3 shows an example in which the outer surface prism cut 22 is provided only on the outer surface 2b side of the reflector 2, and the light from the light source 10 is not provided with the inner surface prism cut 21. Of the first reflection surface 22a and the second reflection surface 22b, and reaches the outer surface prism cut 22. The outer surface prism cut 22 forms a light beam parallel to the irradiation direction X, and again the inner surface 2a. Will be emitted from the reflector 2.

Although not shown, for example, when the reflector 2 is in the intermediate position between FIG. 2 and FIG. 3, both the inner surface prism cut 21 and the outer surface prism cut 22 may be required. The point is that the optimum shape according to various conditions such as the state of inclination of the reflector 2 with respect to the irradiation direction X due to the shape in which the reflector 2 is formed, the angle of the light beam incident from the light source 10, and the like. Is good.

As an opposite case to the above, the reflector 2 is used.
When the degree of inclination with respect to the irradiation direction X and the position of the light source 10 are constant, the light from the light source 10 is irradiated in the irradiation direction X without performing either the inner surface prism cut 21 or the outer surface prism cut 22. It may be parallel to it.

Next, the operation and effect of the reflecting mirror 1 of the present invention having the above-described structure will be described. First, the reflecting body 2 of the reflecting mirror 1 is formed of a transparent member, and basically, In addition, since the parallel rays are obtained by total reflection due to the difference in the refractive index at the boundary surface between the transparent member and the atmosphere, it is possible to reflect the reflector 2 by, for example, forming a reflection film by vapor deposition of aluminum. No additional steps are required.

Further, since the reflector 2 is made of a transparent member, it can be made of resin, for example, injection molding or the like. The reflector 2 can be formed without causing springback or the like due to elasticity, and product accuracy can be improved.

[0014]

As described above, according to the present invention, the reflecting mirror forms a reflector in a substantially bowl shape with a transparent member, and a prism cut formed on the inner surface or outer surface of the reflector or both surfaces thereof. By making the light emitted from the light source a parallel light beam in a predetermined direction by the total reflection occurring on the contact surface between the transparent member and the atmosphere, the reflection mirror is a resin injection molding or the like. With the excellent effect of improving the accuracy of the product as a product that can be formed by, it is possible to simplify the manufacturing process by eliminating the formation of a reflective film as the reflector itself having reflective characteristics, and to improve productivity. It also has an excellent effect on cost reduction.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a reflecting mirror of a vehicular lamp according to the present invention.

FIG. 2 is an enlarged cross-sectional view of a portion A of FIG.

FIG. 3 is an enlarged cross-sectional view of portion B of FIG.

FIG. 4 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Reflector 2 ... Reflector 2a ... inner surface, 2b ... outer surface 21 ... inner surface prism cut 21a ... incident surface, 21b ... emission surface 22 ... outer surface prism cut 22a ... first reflecting surface, 22b ... second reflecting surface X ... irradiation direction

Claims (1)

[Claims] 1. A reflecting mirror of a vehicle lamp that reflects light emitted from a light source as parallel rays in a predetermined direction, wherein the reflecting mirror is formed of a transparent member in a substantially bowl shape, and A vehicle characterized in that the light emitted from the light source is made into parallel rays in a predetermined direction by prism cuts formed on an inner surface, an outer surface or both surfaces thereof, and total reflection occurring on a contact surface between the transparent member and the atmosphere. Reflector for lighting equipment.