JPH0577074B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a vehicle light suitable for use as a tail light, a stop light, etc. The present invention relates to a vehicle lamp in which a Fresnel lens is formed on the lens.

[Conventional technology]

2. Description of the Related Art Conventionally, automobiles have been equipped with various types of lighting such as headlights, taillights, stop lights, and direction indicator lights, and their configurations vary depending on the type of vehicle. Among these, lamps shown in FIGS. 6 to 8 are particularly known as lamps having a double lens structure in which the front opening of the lamp body is covered with an inner lens and an outer lens. A light source 2 is housed in the center of a lamp body 1 that is formed in a box shape long in the left and right direction with an open front, and the front opening of the lamp body 1 is covered with an outer lens 3 and an inner lens 4. A diffusion lens 5 consisting of a large number of small convex lenses is closely formed on the back surface of the outer lens 3, and a diffusion lens 5 made of a large number of small convex lenses is formed on the back surface of the inner lens 4. A Fresnel lens 6 leading to the outer lens 3 is formed. This Fresnel lens 6 has a substantially triangular cross-sectional shape as shown in FIG. It is composed of a large number of sawtooth-shaped steps 7 that protrude concentrically around the optical axis L, and the inclination angle θ of the slope 7a of each step 7 is smaller as it is closer to the center of the optical axis; Therefore, it is set to gradually increase in size. Note that the step 7 forms a complete annular projection at the center, but at the outside it is cut by the upper, lower, left and right ends of the inner lens 4, so that it forms an arc.

[Problem to be solved by the invention]

By the way, in a vehicle lamp having such a configuration, direct light 10 from the light source 2 enters each step 7 of the Fresnel lens 6 and is optically controlled, but as the distance from the optical axis center increases, the light of the step itself becomes weaker. There was a problem with the mountains getting in the way and reducing the amount of light entering each step 7.

That is, as shown in FIG. 8, the entire surface of the slope 7a of each step 7 is not illuminated by the direct light 10 from the light source 2, but rather the slope 7a of each step 7 is illuminated by the direct light 10 from the light source 2. Since the light is blocked by the slope 7a, the shaded slope 71 becomes a shadow of the light.
This is because the inclination angle θ of the step 7 is larger toward the outer side, so the width increases toward the outer side. Therefore, this shadow is directly projected onto the outer lens 5, degrading the quality of the lamp and the illumination effect.

Therefore, the present invention solves the above-mentioned conventional problems, and uses a simple structure to effectively guide light from the light source to the shadowed areas of each step, thereby reducing the occurrence of concentric shadows. It is an object of the present invention to provide a vehicular lamp that can prevent the above.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a lamp body that houses a light source and whose inner surface forms a reflective surface that reflects light from the light source forward, an outer lens that covers the front opening of the lamp body, and an inner lens. This inner lens has a Fresnel lens having a substantially triangular cross-sectional shape and consisting of a number of steps protruding concentrically around the optical axis, and adjacent to the inside of the step on the slope of each step. The part of the inner step that is shaded by direct light from the light source is used as a lens part for controlling the reflected light from the reflecting surface, and this lens part is formed into a prism different from the Fresnel lens step. This is what has been done.

[Effect]

A lens section provided on the inner side of the slope of each step constitutes a reflected light control section that controls light from the reflecting surface, and cancels shadows caused by other steps provided adjacent to the inner side.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is an enlarged sectional view of a main part of a first embodiment of a vehicle lamp according to the present invention, and FIG. 2 is a sectional view of the same lamp. Components that are the same as those in FIGS. 6 to 8 are designated by the same reference numerals, and their explanations will be omitted. In these figures, the inner wall surface of the lamp body 1 forms a paraboloid of revolution reflection surface 11. Therefore, among the light emitted from the light source 2, the reflected light 10a that is reflected by the paraboloid of revolution reflection surface 11 is along the optical axis L.
The light beams become parallel light rays that are substantially parallel to each other, and are directed forward and illuminate the Fresnel lens 6 of the inner lens 4.

Each step 7 constituting the Fresnel lens 6
Of the slope 7a of the step, the part that is shaded by the direct light 10 from the light source 2 due to the other steps provided adjacent to the inside of the step is covered by the light from the paraboloid of revolution reflection surface 11. It constitutes a lens section 14 that controls reflected light 10a. This lens part 1
Numeral 4 has a rough surface that is textured, and causes the reflected light 10a to be diffusely reflected.

Reference numeral 15 denotes a lens mounting portion having a U-shaped cross section and having an annular groove 16 integrally provided in the front opening of the lamp body 1. The outer lens 3 is attached to the annular groove 16.
The side wall tip 3a is inserted and fixed with adhesive 17. On the other hand, inner lens 4
The peripheral edge thereof is fixed to the front opening of the lamp body 1 by ultrasonic welding or the like.

Thus, according to the vehicular lamp having such a configuration, the reflected light 10a that hits the paraboloid of revolution reflection surface 11 is reflected in the portion of each step 7 that is a shadow with respect to the direct light 10 from the light source 2, that is, Since the lens portion 14 is illuminated, shadows can be effectively canceled and a lamp with good visibility can be constructed. In this case, if the lens part 14 is not provided in the shadow part of each step 7, the part will be double irradiated by the direct light 10 from the light source 2 and the reflected light 10a from the paraboloid of revolution reflection surface 11. There is a large difference in brightness between the areas irradiated with only the reflected light 10a, and the shadow cannot be canceled out. However, if the lens section 14 is provided in the area that will be in the shadow as in this embodiment, and the reflected light 10a is diffusely reflected. , the brightness increases and the difference in brightness with the double irradiated area decreases, making it possible to cancel shadows well.

FIG. 3 is a sectional view of a main part showing a second embodiment of the present invention. In this embodiment, the portions of the slopes 7a of each step 7 that are shadowed by direct light 10 are
The back surface 18 of the inner lens 4 is removed, and a lens portion 19 made of a concave lens is formed on the bottom surface. Even in this configuration, since the lens portion 19 controls the reflected light 10a from the paraboloid of revolution reflection surface 11, it is possible to prevent the occurrence of shadows due to the direct light 10.

FIG. 4 is a sectional view of a main part showing a third embodiment of the present invention. In this embodiment, the inner surface of the lamp body 1 is made of a reflecting surface 20 consisting of a simple slope inclined at an appropriate angle with respect to the optical axis, and the light from the light source is reflected forward. is the third
This is similar to the second embodiment shown in the figure. in this case,
Although the reflected light 10a does not become a parallel ray parallel to the optical axis, the maximum height of the step 7 is approximately several mm, and the amount of reflected light 10a incident on the lens portion 19 is not significantly reduced. Therefore, direct light 1
The shadow caused by 0 can be canceled out well.

FIG. 5 is a sectional view of a main part showing a fourth embodiment of the present invention. In this embodiment, the inner surface of the lamp body 1 is formed into a concave curved surface 21 with an appropriate curvature, and a plurality of, for example, four annular shapes are formed on the curved surface 21 at locations corresponding to the lens portions 19 of each step 7. Reflective surfaces 22a, 22b, 22c, and 22d are formed to protrude concentrically around the optical axis.
The annular reflecting surfaces 22a to 22d are each formed of a part of the same paraboloid of revolution with the light source 2 as the focal point. Therefore, among the light emitted from the light source 2, the reflected light 10 that hits the annular reflecting surfaces 22a to 22d
a becomes a parallel ray parallel to the optical axis and points forward,
The lens portion 19 is irradiated. Inner surface 2 of lamp body 1
1 has no function as a reflective surface. Therefore, the slope 7a of each step 7 is irradiated only with the direct light 10, and the amount of light is balanced with the reflected light 10a that irradiates the lens portion 19.

Note that the other configurations are the same as the second embodiment shown in FIG.

〔Effect of the invention〕

As described above, according to the vehicle lamp according to the present invention, in the lamp in which the inner surface of the lamp body is a reflective surface and the inner lens is provided with a Fresnel lens,
The part of the slope of each step of the Fresnel lens that forms a shadow with respect to direct light from the light source is used as a lens part, and the lens part is configured to be irradiated with reflected light that comes out from the light source and is reflected by hitting the reflecting surface. So,
To cancel shadows caused by direct light or make them inconspicuous, to improve lighting effects without impairing the appearance of a lamp when it is lit. Furthermore, since the lens portion controls reflected light through its lens action, uniform illumination of the entire surface of the lens is possible.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of a main part showing a first embodiment of a vehicle lamp according to the present invention, FIG. 2 is a cross-sectional view of the same lamp, and FIG. 3 is a cross-sectional view of a main part showing a second embodiment of the present invention. 4 is a sectional view of a main part showing a third embodiment of the present invention, FIG. 5 is a sectional view of a main part showing a fourth embodiment of the invention, and FIG. 6 is a cross-sectional view of a conventional lamp. FIG. 7 is a front view, and FIG. 8 is a diagram for explaining the occurrence of shadows due to the Fresnel lens. DESCRIPTION OF SYMBOLS 1...Lamp body, 2...Light source, 3...Outer lens, 4...Inner lens, 6...Fresnel lens, 7...Step, 7a...Slope, 7b
. . . Vertical surface, 10 .

Claims (1)

[Claims] A lamp body that houses a light source and has an inner surface that forms a reflective surface that reflects light from the light source forward, and an outer lens and an inner lens that cover the front opening of the lamp body, and the inner lens has a cross section. It has a Fresnel lens that is approximately triangular in shape and consists of a number of steps that protrude concentrically around the optical axis, and direct light from the light source is directed at the slope of each step for the inner step adjacent to the inside of the step. In some cases, the part that becomes a shadow is used as a lens part that controls the reflected light from the reflective surface, and
A vehicle lamp characterized in that the lens portion is formed into a prism different from the Fresnel lens step.