JPH02168502A - Signal lighting fixture for vehicle - Google Patents

Abstract

PURPOSE:To enable the application of thin type design by forming the bottom surface of a housing as a plane mirror and introducing reflected light to a Fresnel lens via the formation of a rotary parabolic reflecting surface or a multi-focal rotary parabolic reflection surface from a position nullifying the plane mirror. CONSTITUTION:A flat type reflection surface 2b is formed around the peripheral surface of a light source 3a at the bottom surface 2a of a housing 2, and light from the light source 3a is thereby reflected to be incidental to the entire surface of a Fresnel lens 4. In addition, a rotary parabolic reflection surface 2c or a multi-focal rotary reflection surface 2d is formed at the peripheral position of the housing 2 nullifying the reflection surface 2b of the bottom surface 2a. Furthermore, Fresnel cuts applied to the lens 4 are such that a direct reflection cut 4a having the light source 3a as a focal point is provided at the center part of the lens 4, and a reflection cut 4b having a focal point at an image 3G projected onto the reflection surface 2b of the light source 3a and a non-reflection part 4c are provided at the outer part of the lens 4, suitably arranged alternately depending upon the ratio of light. According to the aforesaid construction, it becomes possible to obtain equal light intensity over the entire surface of the lens 4 and make the lens 4 thin type.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a signal lamp used, for example, as a taillight of an automobile, and specifically aims to provide a thin lamp.

[Conventional technology]

FIG. 4 shows a conventional lamp 21 of this type.
A Fresnel cut 24a whose focus is set on the light source 23 on the irradiation direction side of the light source 23 housed in the housing 22.
Parallel light rays are obtained by disposing a Fresnel lens 24 which has been subjected to the above-described process, and a predetermined light distribution characteristic is obtained from the lens cut (not shown) made on the front lens 25.

[Problem to be solved by the invention]

For example, taking the example of a taillight, the thickness of the taillight reduces the volume of the trunk of an automobile, and there is a strong demand for thinner taillights in the market. However, when the above-described conventional lamp 21 is designed to be thin, the angle of incidence from the light source 23 entering the periphery of the Fresnel lens 24 becomes shallow, and the amount of light per unit area decreases, resulting in a reduction in the amount of light per unit area. It is unavoidable that the screen becomes dark, and when these points are taken into account, there is a limit to how thin the screen can be made, creating the problem of not being able to meet the demands of the market.

[Means to solve the problem]

The present invention is a specific means for solving the above-mentioned conventional problems, and includes a light source, a housing, and a Fresnel lens. A plane mirror is formed to make the light incident on the entire surface of the Fresnel lens, and at a position other than where the plane mirror is formed, there is a rotating parabolic reflecting surface or a multifocal rotating surface that makes the light from the light source enter the Fresnel lens as parallel light. A Fresnel cut formed on the front surface of the parabolic reflective surface of the Fresnel lens or the multifocal parabolic reflective surface of the Fresnel lens is formed by forming a parabolic reflective surface, and that transparent portions and prism cut portions are alternately arranged. By providing the characteristic vehicle signal lamp, the above-mentioned conventional problems can be solved by making it possible to reduce the thickness.

【Example】

Next, the present invention will be explained in detail based on an embodiment shown in the drawings. What is indicated by the reference numeral 1 in FIG. 1 is a vehicle signal light fixture, and the housing 2 of this vehicle signal light fixture 1 (hereinafter abbreviated as the light fixture 1) is formed in the shape of an approximate figure, and the bottom surface 2 that is the rear side thereof is
A light source 3 such as the filament of a light bulb 3 is placed approximately at the center of a.
A is placed, and a Fresnel lens 4 is placed in the front opening.
is to be installed. It should be noted that an outer lens 5 is attached to the further front surface of the Fresnel lens 4, but since this part is the same as that of the conventional example, a detailed explanation will be omitted here. According to the present invention, a flat reflecting surface 2b is provided on the periphery of the light source 3a of the housing 2, and at this time, the reflecting surface 2b is provided as a plane parallel to the Fresnel lens 4, and its size is The diameter may be sufficient to reflect the light from the light source 3a and make it enter the entire surface of the Fresnel lens 4. With the above configuration, there will be a portion on the peripheral edge of the bottom surface 2a where the reflective surface 2b is not provided, or in other words, a portion where the reflective surface 2b is ineffective even if provided. Therefore, in the present invention, a paraboloid of revolution reflection surface 2c or a multifocal paraboloid of revolution reflection surface 2d is formed in a region where the above-mentioned reflection surface 2b is not provided in order to improve the efficiency of the -layer. To explain from the parabolic reflecting surface 2C, this rotating parabolic reflecting surface 2c has its focal point at the position of the light source 3a, and uses a single paraboloid having an appropriate focal length to reflect the light of the lamp 1 passing through the light source 3a. It is obtained by rotating the optical axis 2 around the optical axis 2, and at this time, the outer diameter of the paraboloid of revolution reflection surface 2c is formed to be the circumcircle of the Fresnel lens 4, as shown in FIG. . Therefore, the parabolic reflection surface 2c
The inner diameter is determined as a range of the thickness of the lamp 1 or a range that does not interfere with the reflective surface 2b. Next, to explain the case of the multifocal rotating parabolic reflecting surface 2d (see the lower half of FIG. 1), this multifocal rotating parabolic reflecting surface 2d has a focal point at the position of the light source, It is a composite of multiple paraboloids of revolution with different focal lengths, with a paraboloid of revolution with a short focal length placed on the outer diameter side, and paraboloids of rotation with long focal lengths successively arranged toward the inner diameter side. By doing so, the so-called inclination becomes gentle, and it becomes possible to increase the reflective area for the same thickness in the front and back direction. The light reaching the Fresnel lens 4 from the light source 3a and the reflecting surface 2b12c or 2d of the housing 2 configured as described above is (1) direct light that enters radially from the light source 3a. ■ Reflected light that enters radially after being reflected from the light source 3a onto the reflective surface 2b. (2) Reflected light that enters as parallel light after being reflected from the light source 3a to the paraboloid of revolution reflection surface 2C or the multifocal paraboloid of revolution reflection surface 2d. There are three types. Comparing each of these three types of light, when this type of lamp 1 is made thin, the Fresnel lens 4 and the light source 3a are extremely close to each other, so the area directly above the light source 3a, that is, the optical axis 2
It is extremely bright in the vicinity of , but as it moves to the periphery, the angle of incidence on the Fresnel lens 4 tilts and the brightness decreases rapidly. The mapping 3G is the apparent position of the light source 3a,
In other words, it recedes and the above-mentioned variation in the angle of incidence becomes smaller,
The brightness decreases in the vicinity of the optical axis Z, but increases at the periphery. When the lamp 1 is made thinner, (2) reflects the side light from the light source 3a, so it is possible to make the area brighter than 0 in the area where (2) enters at 451 or less. For the above reason, the central part of the Fresnel lens 4, that is, the optical axis 2
The light intensity is in the order of ■〉■〉■ near the
ku■≦■. Therefore, the Fresnel cut applied to the Fresnel lens 4 has a direct cut 4a with the light source 3a as the focal point at the center, and a reflection surface 2b of the light source 3a at the periphery.
If the reflective lens 4b and the transparent portion 4C, which are focused on the map 3G projected on the surface of the lens, are appropriately arranged alternately according to the brightness ratio, bright brightness can be achieved over the entire surface of the Fresnel lens 4. It's what you get. FIG. 3 shows an example in which the present invention is applied to a lamp 1 in which a plurality of light sources 3a are attached from the side surface of a housing 2. For example, if four light sources 3a are installed, this lamp 1
In this case, four optical axes 2 are grown, and reflective surfaces 2b are formed near each of the optical axes 2 by the same means as in the previous embodiment, and even if the above-mentioned reflective surfaces are provided, it is ineffective. The part that becomes occurs in the center of the Fresnel lens 4,
Therefore, the paraboloid of revolution reflection surface 2c (shown in the upper half of the figure) or the multifocal paraboloid of revolution reflection surface 2d (shown in the lower half of the figure)
are provided in a shape that raises the vertical and horizontal center lines of the bottom surface 2a of the housing 2. Therefore, the Fresnel cut applied to the Fresnel lens 4 also involves dividing the Fresnel lens 4 into four equal parts along the vertical and horizontal center lines.
A direct cut 4a, a reflection cut 4b, and a transparent part 4c may be provided in each section, centering on the respective optical axis Z, in the same manner as described in the previous embodiment. In the case of this embodiment, there is no need to provide the socket hole for the light source 3a in the reflective surface 2b as seen in the previous embodiment.
Although not shown, the direct light beam 4a may be omitted and the reflection beam 4b may be provided from the front surface of the light source 3a. The operation of this embodiment is completely the same as that of the previous embodiment, so detailed explanation will be omitted here.

【Effect of the invention】

As explained above, according to the present invention, by forming a reflective surface of a flat cane on the housing and projecting a light source onto this reflective surface, the position of the upper light source is apparently moved backward, and it is also moved toward the Fresnel lens side. A reflective cut is applied to the corresponding position to prevent the brightness from extremely decreasing at the periphery, and in addition, a reflective surface such as a paraboloid of revolution is added to the position where the reflective surface becomes ineffective. Furthermore, it has the excellent effect of increasing light utilization efficiency, preventing the occurrence of moderate unevenness, making it possible to reduce the thickness of vehicle signal lamps, and meeting market demands.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a vehicle signal lamp according to the present invention, FIG. 2 is a front view showing main parts of the same embodiment, and FIG.
This figure is a sectional view of another embodiment of the present invention, and FIG. 4 is a sectional view of a conventional example. 1... Vehicle signal light 2... Housing 2a... Bottom surface 2b... Reflective surface 2c... Rotating parabolic reflecting surface 2d... Multifocal rotating parabolic reflecting surface 3... Bulb 3a... Light source 3G...Mapping 4...Fresnel lens 4a...Direct cut 4b...Reflection cut 4C...Transparent section 5...Outer lens 2...Optical axis Patent applicant Stanley Electric Co., Ltd. Company agent Teru Homoto No. 1 Figure 3

Claims (2)

[Claims] (1) Consisting of a light source, a housing, and a Fresnel lens, a plane mirror is formed on the bottom surface of the housing to create a mapping that is parallel to the Fresnel lens and causes the light from the light source to enter the entire surface of the Fresnel lens. In addition, at a position other than where the plane mirror is formed, a paraboloid of revolution reflection surface or a multifocal paraboloid of rotation reflection surface is formed to make the light from the light source enter the Fresnel lens as parallel light, and the Fresnel lens includes For a vehicle, characterized in that a reflection cut is made with the mapping as a focal point, and the Fresnel cuts are arranged alternately with transparent parts on the front surface of the paraboloid of revolution reflection surface or the multifocal paraboloid of revolution reflection surface. Signal light equipment. (2) The vehicular signal lamp according to claim (1), wherein a direct cut with the light source as a focal point is provided on the front surface of the light source of the Fresnel lens.