JPS6364842B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicular lamp, and more particularly to a vehicular lamp in which the brightness of a lens surface is made uniform and visibility is improved.

In recent years, this type of vehicle lighting has been made to have a shallower depth and thinner design, so instead of using a paraboloid of revolution reflector that takes up space, a direct prism is formed on the front lens to reflect the light emitted from the light source. A vehicular lamp has been proposed in which direct light is controlled by the direct-ray Fresnel prism.

As shown in FIG. 1, a conventional vehicular lamp equipped with a front lens formed with a direct-light Fresnel prism has a light source c disposed in a lamp chamber defined by a housing a and a front lens b, lens b
has an outer lens d with a fisheye prism e formed on its inner surface, and a refractive prism in the center facing the light source c in order to control the emitted light (direct light) from the light source c as a ray almost parallel to the optical axis X. It consists of an inner lens f that forms a lens g and has reflective prisms h and h' on its outer periphery, and directs the emitted light (direct light) from the light source c to the optical axis X using a direct Fresnel prism as shown in the figure. The light beam is made into parallel light beams and condensed by a fisheye prism e of an outer lens d to obtain a desired light distribution pattern.

However, in such a conventional vehicle lamp, since the front lens b is formed into a planar shape and is disposed in the housing a, the inner lens f
Synchrotron radiation (direct light) that enters the refractive prism section g provided at the center facing the light source c of the direct Fresnel prism formed in As shown in the figure, the light is incident only within the range of angle α°, and therefore the utilization rate of the luminous flux is low. In particular, the light incident on the reflective prisms h and h' on the outer periphery far from the light source c is within the range of angles β ₁ and β. ₂ , the amount of luminous flux is small and the luminous flux density decreases, so the central part of the inner lens f facing the light source c appears bright, but the outer periphery becomes a dark part, which not only makes the lighting filling unsightly, but also makes it difficult to use for signal lights. There is a problem that display functions such as cannot be fully achieved.

In order to improve this problem, we installed an inner lens with a Fresnel cut on the side of the light source, which is approximately parallel to the optical axis, and which is oriented approximately perpendicular to the optical axis emitted from the inner lens. A lamp has been proposed in which a reflective surface is formed that totally reflects the light beam in the direction of the optical axis, thereby eliminating the dark area on the outer periphery of the lamp (see Japanese Utility Model Application No. 56-2503).

According to this proposal, the problems of the prior art as shown in FIG. 1 can be solved to some extent.

However, in the lamp having the structure shown in the above-mentioned Japanese Utility Model Publication No. 56-2503, the front lens is horizontally long and the outer periphery of the lens is extended to a position away from the light source, and the depth dimension of the lamp is In cases where the inner lens is limited (thin), the inner lens must be placed away from the light source, so the amount of direct light directed to the side of the light source is reduced, making it possible to sufficiently eliminate dark areas. The problem is that it is not possible to In addition, as mentioned above, when the front lens is horizontally long, it is possible to arrange an inner lens close to the light source to increase the amount of direct light directed to the side. The depth dimension of the lamp becomes large, making it impossible to make the lamp thinner. As described above, the structure shown in the above-mentioned Japanese Utility Model Publication No. 56-2503 is subject to restrictions on the setting of the lamp design, especially when the front lens is horizontally long and large in size. This is not sufficient to eliminate dark areas.

The present invention aims to improve the problems of the prior art as described above, and to provide a vehicle lamp that is thin enough and bright enough to the outer periphery even when the front lens is horizontally long and large in size. .

In order to achieve the above object, the present invention disposes a light source in a lamp chamber defined by a housing and a lens disposed in front of the housing, and the lens is composed of an outer lens and an inner lens. In a vehicle lamp, a Fresnel prism that emits direct light from the light source approximately in the direction of the optical axis is provided in the central part of the inner lens facing the light source,
A first side lens and a second side lens are arranged at a distance from each other to be substantially parallel to the optical axis on the side of the light source, and a reflecting section is arranged outside of the second side lens. A Fresnel prism is formed on the inner surface of the first side lens facing the light source, and a Fresnel prism is formed on the outer surface of the first side lens, and a Fresnel prism is formed on the outer surface of the first side lens. A plurality of cylindrical prisms are provided for condensing light made substantially parallel to the horizontal axis by the Fresnel prism and making it enter the second side lens, and the first side of the inner surface of the second side lens is provided. A plurality of cylindrical prisms are provided at the incident position of the focused light from the first side lens to make the focused light from the first side lens into a beam substantially parallel to the horizontal axis, and the reflecting portion is provided with a plurality of cylindrical prisms that convert the focused light from the first side lens into light beams substantially parallel to the horizontal axis. It is characterized by the provision of a plurality of reflective surfaces that reflect incident light rays toward the outer periphery of the lens substantially parallel to the optical axis.

As described above, the vehicle lamp of the present invention does not directly make the light rays made almost parallel to the horizontal axis perpendicular to the optical axis by the Fresnel prism of the first side lens incident on the reflecting surface. , the light beam condensed by the cylindrical prism of the first side lens is made incident on the second side lens, and the incident light is again converted into a light beam substantially parallel to the horizontal axis by the cylindrical prism of the second side lens. Since the parallel rays are reflected approximately parallel to the optical axis by a plurality of reflecting surfaces and incident on the outer circumferential portion of the lens, the first side lens can be set at a position where any desired luminous flux can be obtained. and the distance between the first side lens and the second side lens is arbitrary, and therefore,
Even if the lens is horizontally long and large, it is possible to make the lamp thinner and emit a sufficient amount of light that is approximately parallel to the optical axis from the outer periphery of the lens so that it can spread over the entire surface of the lens. A lamp with uniform brightness can be obtained.

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

FIG. 2 is a cross-sectional view of the main parts of the present invention applied to an automobile taillight, in which numeral 1 indicates a housing, and the housing 1 and the lens 2 disposed on the front thereof.
A bulb 5 serving as a light source is attached to a holder 52 via a socket 51 in a lamp chamber 10 defined by the above. The front lens 2 consists of an outer lens (cover lens) 21 and an inner lens 22 inside the outer lens 21. A fisheye prism 22a is provided on the outer surface of the inner lens 22, and an optical axis X (of the lamp) facing the bulb 5 on the inner surface is provided. A direct radiation Fresnel prism 22b is formed in the central portion 6 near the reference axis), and flat portions 22c and 22d are formed in the outer peripheral portions 7 and 8 far from the bulb 5.

In the present invention, optical means 3 and 4 disposed on both sides of the bulb 5 are used to allow a large amount of light to enter the outer peripheral portions 7 and 8 of the inner lens 22 that are far from the bulb 5. The optical means 3, 4 include first lateral lenses 31, 41 disposed on the sides of the light source 5, and second lateral lenses 32, 42 disposed apart from the first lateral lenses. , reflective portions 33 and 43 disposed outside the second side lens.
The first and second
The side lenses are arranged substantially parallel to the optical axis.
The first side lenses 31, 41 have a Fresnel prism 31a on their inner surfaces that controls the radiation emitted laterally from the bulb 5 into a beam substantially parallel to the horizontal axis Y orthogonal to the optical axis X. 41a,
Moreover, a plurality of cylindrical prisms 3 are provided on the outer surface.
1b and 41b are formed. The cylindrical prisms 31b, 41b converge the light beams made almost parallel by the Fresnel prisms 31a, 41a, and emit them toward the cylindrical prisms 32a, 42a provided in the second side lenses 32, 42. belongs to. Second lateral lens 32, 4
2 forms the cylindrical prisms 32a, 42a corresponding to the cylindrical prisms 31b, 41b of the first side lenses 31, 41, and the cylindrical prisms 32a, 42a
further refracts the focused light beam from the first side lenses 31, 41 into a light beam substantially parallel to the horizontal axis Y, and makes the light beam incident on the incident surfaces 33a, 43a of the reflecting portions 33, 43, The outer peripheral portion 7 of the inner lens 22 is reflected almost parallel to the optical axis X by the outer reflective surfaces 33b and 43b through the wall thickness.
The structure is such that a large amount of light beam is incident on flat parts 22c and 22d provided at 8.

More specifically, the first side lenses 31, 41
and second side lenses 32, 42 are Fresnel lenses disposed on the sides of the bulb 5 substantially parallel to the optical axis X, and provided on the inner surfaces (light source side) of the first side lenses 31, The prisms 31a and 41a are formed centered on the horizontal axis Y. Furthermore, the cylindrical prisms 31b and 41b provided on the outer surfaces and the cylindrical prisms 32a and 42a provided on the inner surfaces of the second side lenses 32 and 42 are configured to correspond to each other, respectively. Furthermore, the second side lens 32,
42 cylindrical prisms 32a, 42a
and each reflective surface 33b provided in the reflective parts 33, 43,
43b are configured to correspond to each other. Note that the illustrated reflecting portions 33 and 43 have step-like incident surfaces 33a and 43a formed on their inner surfaces using a transparent material, and reflective surfaces 33b and 43 formed on their outer surfaces.
3b and step portions 33c and 43c, the present invention is not limited to this embodiment.

Since the vehicle lamp of the present invention has the above-described configuration, when the bulb 5 is turned on, the light emitted forward from the bulb 5 is directed to the inner surface of the central portion 6 of the inner lens 22, as shown by the solid line. The light enters the Fresnel prism 22b, is refracted by the Fresnel prism 22b into a ray substantially parallel to the optical axis It is ejected forward. Further, the light emitted to the side of the bulb 5 enters the first right side lens 31 and the left first side lens, respectively, as shown by the dotted line, and enters the Fresnel prism 31 of the first side lens.
cylindrical prism 31b on the rear outer surface, which is refracted by a, 41a into a ray substantially parallel to the horizontal axis Y;
41b as a focused light, and the focused light beam enters the cylindrical prisms 32a, 42a provided on the inner surfaces of the second side lenses 32, 42, and the cylindrical prisms 32a, 42a of the second side lenses 32, 42 42a, the light beam is refracted into a ray substantially parallel to the horizontal axis Y, and is reflected by the outer reflecting portion 33,
The light enters the incident surfaces 33a, 43a of the inner lens 22, passes through the wall thickness, enters the outer reflective surfaces 33b, 43b, and is directed toward the outer peripheral portions 7, 8 of the inner lens 22 by the respective reflective surfaces 33b, 43b. A large amount of reflected light with a high luminous flux density is reflected into rays substantially parallel to the optical axis 21 and is emitted.

That is, the vehicle lamp of the present invention has a bulb 5.
Of the direct light emitted from the inner lens 22
The amount of light incident on the central portion 6 is the same as in the conventional case within the range of angle α° ₁ shown by the solid line in FIG. The light emitted laterally from the bulb 5 has a luminous flux between the range of angle α° ₂ on the right side and the range of angle α° ₃ on the left side shown by the dotted line between the first side lenses 31, 41 and the second side lens. The light enters the outer circumferential portions 7 and 8 of the lenses via the lenses 32 and 42 and the reflecting portions 33 and 43 as light rays parallel to the optical axis. As described above, in the present invention, the first side lens can be disposed at a position where a desired luminous flux can be obtained, and the distance between the first side lens and the second side lens can be set arbitrarily. Even if the lamp is horizontally long and has large dimensions, a large amount of light can be incident on the outer peripheral parts 7 and 8 of the lens almost parallel to the optical axis X, making the brightness uniform over the entire surface of the lens. can be done.

As described above, according to the present invention, even when the front lens is horizontally long and large in size, it is possible to reduce the thickness of the front lens while still transmitting light that is approximately parallel to the optical axis from the outer periphery as well as from the center of the lens. It is possible to provide a lamp that emits light and has substantially uniform brightness over the entire surface of the lens.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a conventional vehicle lamp. FIG. 2 is a sectional view of a main part of an embodiment of a vehicle lamp according to the present invention, and FIG. 3 is an explanatory diagram showing a luminous flux utilization range. DESCRIPTION OF SYMBOLS 1...Housing, 2...Front lens, 22a...Fisheye prism, 22b...Fresnel prism, 31,
41... First side lens, 31a, 41a... Fresnel prism, 31b, 41b... Cylindrical prism, 32, 42... Second side lens, 32a,
42a...Cylindrical prism, 33,43...
Reflection part, 33b, 43b... Reflection surface, 5... Bulb,
6...Central part, 7, 8...Outer circumferential part, X...Optical axis, Y...Horizontal axis.

Claims (1)

[Claims] 1. A light source is disposed within a lamp chamber defined by a housing and a lens disposed on the front surface of the housing, and the lens is composed of an outer lens and an inner lens, and a central portion facing the light source on the inner surface of the inner lens. In a vehicle lamp equipped with a Fresnel prism that emits direct light from a light source substantially in the optical axis direction, a first side lens and a second side lens are provided on the side of the light source substantially parallel to the optical axis. are arranged at a distance from each other, and a reflecting part is arranged outside the second side lens, and a reflecting part is arranged outside the second side lens, and the light emitted from the light source is directed laterally to the inner surface of the first side lens facing the light source. A Fresnel prism is formed to control light to be substantially parallel to a horizontal axis perpendicular to the axis, and the light made substantially parallel to the horizontal axis by the Fresnel prism is focused on the second side lens on its outer surface. a plurality of cylindrical prisms are provided, and the second
A plurality of cylindrical prisms are provided at a position on the inner surface of the side lens at which the focused light from the first side lens is incident, and furthermore, a plurality of cylindrical prisms are provided to convert the focused light from the first side lens into light beams substantially parallel to the horizontal axis. A vehicular lamp characterized in that a plurality of reflecting surfaces are provided on the second side lens to reflect the light rays incident from the second side lens toward the outer circumference of the lens substantially parallel to the optical axis.