JPS5913121B2 - Vehicle lights - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicular lamp, and more particularly to a vehicular lamp using a lens provided with a direct-ray Fresnel prism.

This type of vehicle light uses direct light from the light source without using a rotating paraboloid flap, which takes up space, as the space inside the vehicle body where the light is stored, especially in the trunk, increases. 2. Description of the Related Art A vehicular lamp has been proposed in which light is controlled by a lens to emit light, and the lamp is made smaller, thinner, and lighter.

That is, FIG. 1 shows a conventional lamp, in which a light source bulb p is arranged in a lamp chamber g in which a housing a and an outer lens b and an inner lens C are disposed on the front surface of the housing a.

A fisheye prism d is provided on the inner surface of the outer lens b,
A refractive prism section e is provided concentrically at the center of the inner surface of the inner lens C, and a reflective prism f is provided at the periphery of the refractive prism section e to provide a Fresnel cut.

However, such conventional vehicle lamps are as shown in FIGS. 2A to 8. For example, in FIG. The prism can be set to satisfy the light distribution, so it looks bright from the outside.

However, in this refractive prism e, the angle range in which the light beam from the light source p enters an equal area on the front surface of the lens, for example, an area corresponding to one element of the prism, is an angle θ1 near the center, but as it gets farther from the center, It gradually becomes smaller and reaches an angle θ2 near the boundary with the reflective prism f.

Naturally, since θ, >θ2, the amount of light incident on the part far from the center is small, and the surrounding area becomes dark.

Further, as shown in the figure, the light incident on the hanging portion (rising portion) H of the refractive prism e becomes lost light (light emitted far from the optical axis).

That is, although direct light from the light source p is incident on the hanging surface (rising portion) H of the refractive prism e, it is diffused as lost light.

Also, the angle difference between the angle of light toward the inclined surface A of the refractive prism e and the angle of the light toward the hanging surface H increases as the prism e moves away from the optical axis central axis Z. Therefore, the lost light The solid angle δ of the area is the solid angle δ□〈δ.

As a result, the loss of light increases, and the peripheral area becomes a dark area F, and this dark area F appears particularly prominently in a lamp that is elongated from side to side.

In addition, as shown in the figure, the light ray L0 incident on the refractive prism e is received by the inclined surface A of the prism element, is refracted, passes through the element as it is, and exits from the surface B, which is the lens surface, so there is a loss due to attenuation. On the other hand, the incident light beam L2 to the reflective prism f is received by the C-plane of the hanging surface of the prism element, refracted, further reflected by the inclined surface, and exits from the lens surface.

Therefore, the light rays exiting through the reflecting prism f are attenuated more than those passing through the refractive prism e, resulting in a significant loss.

Therefore, the output luminous intensity suddenly decreases at the boundary E between the refractive prism e and the reflective prism f, and as a result, when viewed from the outside, there is a sharp difference in brightness near this boundary with the center, and when viewed from the front, a ring-shaped This results in a dark portion F.

When looking at the lens surface, the presence of such dark F not only makes the lighting filling bad and unsightly, but also makes it impossible for the lens to emit light uniformly, impairing the light distribution function, and also impeding display functions such as signal lights. There are disadvantages such as not being able to achieve sufficient visibility and ensuring visibility.

In view of the above-mentioned circumstances, the present invention makes maximum effective use of the light beam in the central area near the center of the optical axis, eliminates the loss of light especially at the rising part (downward surface) of the refractive prism part, and It is an object of the present invention to provide a vehicular lamp that eliminates the dark part that occurs at the boundary with a reflective prism part, increases the tolerance of the amount of light, enables a uniform light emitting surface, and thereby improves visibility.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of the implementation of a vehicle lamp according to the present invention will be described below with reference to the accompanying drawings.

The illustrated examples in FIGS. 3 to 5 are the first embodiment of the present invention, in which 1 is a housing defined by an outer lens 2 and an inner lens 3 disposed on the front surface of the housing 1. This is a vehicular lamp in which four light source bulbs are held in a holder 42 via a socket 41 and arranged in a lamp chamber 5.

The outer lens 2 and the inner lens 3 are molded from a transparent synthetic resin such as acrylic resin.

The outer lens 2 has a fisheye prism portion 21 on its inner surface.
are arranged in a lattice pattern, and the inner lens 3 has a lattice-shaped refraction prism section 31 formed on the outer surface 30a of the central part near the optical axis center Z, and an inner surface 30b of the refraction system prism section 31. A light scattering prism section 33 is provided at the central portion.

Further, a lattice-shaped reflective prism section 32 is formed around the diffuser prism section 33.

More specifically, the inner lens 3 has a central part near the optical axis center Z (a part near the light source 4), as shown in FIGS.
A refractive prism section 31 is formed on the outer surface 30a of the refractive Fresnel prism section 31, which is formed by cutting refractive Fresnel prisms vertically and horizontally and arranged in a lattice shape (the ridge lines appear in a lattice shape). A large number of convex light scattering prism parts 33 having a small prism part 33a at the center and very small prism parts 33b around the small prism part 33b are arranged at the center of the inner surface 30b of the position. Reflection prism portions 32 are arranged in a grid pattern.

Since the configuration is as described above, when the light is turned on, the fifth
As shown in the figure, among the emitted light from the light source 4, the incident light beam L1. L2 first enters the small prism section 33a at the center of the diffusing prism section 33, is refracted and transmitted as a large diffused light, and is refracted again at the inclined surface of the prism element of the lattice refraction system prism section 31 on the outer surface 30a. All of the light is emitted as large diffused light, and a large amount of light flux is emitted in the direction of the fisheye prism portion 21 of the outer lens 2.

The light ray L2 incident on the minimal prism section 33b in the peripheral portion of the diffuser prism section 33 is refracted as a small diffused light by the minimal prism section 33b and transmitted through the inclined surface of the prism element of the lattice refraction system prism section 31 on the outer surface 30a. The light is refracted again and all of the light is emitted as small diffused light, and a large amount of light is emitted in the direction of the fisheye prism section 21 of the outer lens 2.

Furthermore, the incident light beam L3 to the reflective prism section 32 is received by the hanging surface (rising part) of the prism element, refracted, and further reflected by the inclined surface to form a light beam substantially parallel to the optical axis on the outer surface 30.
The light is emitted from the outer lens a, is condensed into a necessary light distribution by the fisheye prism portion 21 of the outer lens, and is emitted from the outer surface of the outer lens 2 with directionality.

However, since the refractive prism portion 31 is formed at the center of the outer surface 30a near the optical axis center Z of the inner lens 3, the rising portion (downward surface) of this prism element
Since no light is incident on H', there is no loss of light, and since the light scattering prism section 33 is formed at the center of the inner surface 30a, the light is diffused in the central region where the luminous flux density is high. Refraction system prism section 3 on outer surface 30a
10 By emitting diffused light in the peripheral direction, dark areas do not occur at the boundary between the refractive prism section 31 and the reflective prism section 32, and the entire surface of the lens can emit light with uniform brightness. .

The illustrated example in FIG. 6A and FIG.
The inner lens 3 has a simple refractive prism part 310a in which a refractive prism part 310 is concentrically formed in the central part of the outer surface 30a near the optical axis center Z, and a rising part (downward surface) is formed in the center substantially parallel to the optical axis. The rising part H in the peripheral part far from the optical axis center is formed with a total refraction system prism part 310b tilted outward with respect to the optical axis, so that it has a rectangular shape (reference character K in the figure) as shown in the figure. A light scattering prism section 33 is provided at the center of the inner surface 30b corresponding to the concentric refraction prism section 310, and a concentric reflection prism section 320 is formed around the dispersion prism section 33.

In the inner lens 3 of this example, the concentric refractive prism section 310 on the outer surface 30a has a simple refractive prism section 310a near the center of the optical axis, and a fully refractive prism section 310a in the surrounding area far from the center of the optical axis. Since the portion 310b is formed, no light enters the rising portion (hanging portion) H′ of the prism element, resulting in loss of light.
Diffusion prism portion 3 provided at the center of the inner surface 30a
3, the light emitting surface at the center of the lens can emit light with almost uniform brightness, and furthermore, there is no dark area at the boundary between the refractive prism section 310 and the reflective prism section 320, which further improves the lighting feeling. It is good and has the effect of improving visibility.

The illustrated examples in FIGS.
In place of the concentric refractive prism part in a, in this example, a refractive prism part 311, which is formed by cutting a refractive Fresnel prism vertically and horizontally and arranged in a lattice pattern, is arranged in a rectangular shape (numerals in the figure). A light scattering prism section 33 is provided at the center of the inner surface 30a, and a reflective prism section 320 is formed concentrically around the diffuser prism section 33.

Incidentally, the lattice-like refraction system prism section 311 has a simple refraction system prism section 311a in a part near the optical axis center and a peripheral part far from the optical axis center, similar to the concentric refraction system prism part in the above-described embodiment. Full refraction system prism part 311 in the part
b is formed, and has the same effect as the second embodiment.

In addition, in the above-mentioned embodiment, the light scattering prism part 33 provided at the central part of the inner surface of the inner lens 3 is not limited to a convex shape, but may be a concave light scattering prism part, and furthermore, it may be formed of only small prism parts. Also good.

In addition, a large number of scattering prism parts 33 are regularly arranged, but in another embodiment, they are arranged densely near the center of the high axis where the luminous flux density is high, and in the peripheral part where the luminous flux density is low. The light scattering prism portion 33 may be formed so that the light is coarse, or the curvature of the light scattering prism portion 33 may be formed so that the curvature is small near the center of the optical axis, and the curvature increases toward the periphery. It is something.

As is clear from the above-described embodiments, the vehicular lamp of the present invention is a lamp in which a light source is disposed within a lamp chamber defined by a housing, an outer lens and an inner lens disposed in front of the housing, and The inner lens is characterized in that a refractive prism portion is formed at the center of the outer surface near the center of the optical axis, a diffusing prism portion is provided at the center of the inner surface, and a reflective prism portion is formed at the periphery of the inner lens. Therefore, the luminous flux in the region with high luminous flux density can be effectively used without loss, and in particular, the luminous flux can be effectively utilized to the maximum extent in the central area near the optical axis center, which constitutes the refractive prism section and the scattering prism section. By utilizing this technology, a dark area does not occur at the boundary between the refractive prism part and the reflective prism part and damage the lighting filling, unlike in the past, and a uniform light-emitting surface can be obtained over the entire lens surface. This provides effects such as being able to emit light with a high intensity of light and improving visibility.

It should be noted that, as a matter of course, the present invention is not limited only to the examples.

[Brief explanation of drawings]

Figures 1 and 2 show a conventional lamp, where Figure 1A is a front view of the lamp, the opening of the figure is a sectional view taken along line A-A in Figure I, and Figure 2 is a front view of the lamp.
Figures A to C are explanatory diagrams showing the optical action of conventional lenses.
5 to 5 show a first embodiment of the vehicle lamp of the present invention, FIG. 3A is a front view, the opening of the figure is a sectional view taken along line B-B of FIG. 4, and FIG. 4A is an inner lens. The opening in the same figure is a cross-sectional view taken along the line C-C in Figure A, and the figure C is a cross-sectional view taken along the line D-D in Figure A.
The figure is a partially cutaway enlarged view of the inner lens and is an explanatory diagram showing the light effect, and Figure 6A and the mouth indicate the 20th actual flow side of the present invention,
1A is a front view of the lamp, the opening in the figure is a sectional view taken along the line E-E in Figure 1, FIGS. The opening of the figure is F-E in figure A.
Line sectional view, the same figure C is a GG line sectional view in figure A. 1...Housing, 2...Outer lens, 3...Inner lens, 31...
・Refraction prism section, 32...Reflection prism section, 33...Diffusion prism section, 4...
light source.

Claims (1)

[Claims] 1 A lamp in which a light source is arranged in a lamp chamber defined by a housing and an outer lens and an inner lens arranged on the front surface of the housing, wherein the inner lens refracts the light to the center of the outer surface near the center of the optical axis. form the system prism part,
What is claimed is: 1. A vehicular lamp, further comprising: a diffuser prism portion provided at the center of the inner surface thereof, and a reflective prism portion formed at the periphery of the diffuser prism portion.