JP2006092887A - Lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp such as a vehicular lamp using a light emitting element as a light source, which prevents color separation with a simple and small configuration.
A light source using a light emitting element and having an optical axis extending forward, a first focal point F1 thereof is positioned in the vicinity of the light emission center of the light source, and a second focal point F2 thereof from the first focal point to the above. The first reflecting surface 12 of the spheroid system that is located above and perpendicular to the optical axis, and the focal point is the second focal point of the first reflecting surface. A second reflecting surface 13 of a rotary paraboloidal system that is concave toward the front and whose optical axis intersects the major axis perpendicular to the first reflecting surface at an angle of 90 degrees or less. And a light-shielding portion 14 disposed in the vicinity of the second focal point of the first reflecting surface so as to form a predetermined cutoff with respect to light traveling from the first reflecting surface to the second reflecting surface. The lamp 10 is configured to include
[Selection] Figure 1

Description

  The present invention relates to a lamp suitable for a vehicle lamp such as a vehicle headlamp using at least one light emitting element.

With the recent improvement in luminous efficiency of white LEDs, various vehicle headlamps using white LEDs as light sources have been proposed.
A vehicle headlamp using such an LED is a so-called projector-type vehicle headlamp, and includes a light source composed of at least one LED, a reflector that reflects light from the light source forward, The projection lens for converging the light reflected by the reflector, and a light shielding part for forming a cutoff for passing light distribution.

Here, the reflector is composed of, for example, a spheroidal surface, and the light emission center of the light source is disposed in the vicinity of the first focal position.
The projection lens is composed of a convex lens, and is arranged such that the focal position on the bulb side is located near the second focal position of the reflector.

  According to the vehicle headlamp having such a configuration, the light emitted from the light source is reflected by the reflector, travels toward the second focal point of the reflector, is focused by the projection lens, and is irradiated forward. The At that time, a cut-off is formed by the light-shielding portion to illuminate a range of a so-called passing beam light distribution pattern.

By the way, in these vehicle headlamps, since the reflected light from the reflector is focused by the projection lens and irradiated forward, color separation occurs due to the chromatic aberration of the projection lens. End up. In addition, the reflector, the projection lens, and the light-shielding portion need to be accurately positioned and arranged with respect to the light source, resulting in a problem that the number of parts is large and the assembling work becomes complicated.
Further, not only LEDs but also small light sources using other types of light emitting elements have similar problems.

  In view of the above, an object of the present invention is to provide a lamp such as a vehicular lamp that uses a light-emitting element as a light source, which prevents color separation with a simple and small configuration.

  According to the present invention, the object is to provide a light source comprising at least one light emitting element and having an optical axis extending substantially horizontally forward, and light radiated forward from the light source from vertically upward to diagonally backward. The first focal point is positioned near the light emission center of the light source so that the light is reflected, the second focal point is positioned above the first focal point and perpendicular to the optical axis, and is approximately from the central axis. The first reflecting surface of the spheroid system formed only on the front side, and the focal point is the second reflecting surface of the first reflecting surface so as to reflect the light from the first reflecting surface forward. A second reflecting surface of a rotary paraboloidal system that is concave toward the front and whose optical axis intersects at an angle of 90 degrees or less with respect to the long axis perpendicular to the first reflecting surface. And part of the light traveling from the first reflecting surface to the second reflecting surface by the upper edge A light-shielding portion disposed near the second focal point of the first reflecting surface so as to form a cutoff suitable for a predetermined light distribution pattern. This is achieved by the lamp.

  In the lamp according to the present invention, preferably, the second reflecting surface is integrally provided with a holding portion for fixing and holding the light source and the light shielding portion.

  In the lamp according to the present invention, preferably, the first reflection surface, the second reflection surface, and the light shielding portion are integrally formed.

  In the lamp according to the present invention, preferably, the first reflecting surface, the second reflecting surface, and the light shielding portion are integrally formed of a transparent material, and correspond to the first reflecting surface and the second reflecting surface. A reflective film is formed on the surface area to be formed, and an opaque film is formed on the surface area corresponding to the light shielding portion.

  In the lamp according to the present invention, preferably, the first reflecting surface is composed of a composite ellipsoid.

  In the lamp according to the present invention, preferably, the lamp is a vehicle lamp, particularly a vehicle headlamp, and the light shielding portion forms a cut-off corresponding to a light distribution pattern of a low beam.

  According to the above configuration, the light emitted forward from the light source is reflected by the first reflecting surface and travels while converging toward the second focal point. And the light which passed the 2nd focus, ie, the focus of a 2nd reflective surface, injects into a 1st reflective surface, diverging. Thereby, the light reflected by the 1st reflective surface is irradiated toward the front.

  At that time, a part of the light reflected by the first reflecting surface and directed to the second reflecting surface is cut off by the light shielding portion, and the cutoff line by the light shielding portion is The light is reflected by the reflecting surface, converged, and projected forward. As a result, the cut-off line image is formed at a predetermined distance in front, whereby light is irradiated with a predetermined light distribution pattern, for example, a low beam light distribution pattern.

In this case, since the light source is composed of a light emitting element such as an LED, the amount of heat generated by the light emission is extremely small. Therefore, even if the light shielding part is arranged close to the light source, the light shielding part is Since it is not so much affected by heat generation, it can be made compact as a whole.
Further, since the major axis of the first reflecting surface is arranged substantially vertically, a light distribution pattern that is narrow in the vertical direction and wide in the horizontal direction can be easily obtained, and can be configured to be small in the horizontal direction. It will be.
Furthermore, the light distribution pattern can be set to an arbitrary shape by appropriately changing the shape of the first reflecting surface, and can be set to an arbitrary size by appropriately changing the focal length of the second reflecting surface. Can be set.

  In the case where the second reflecting surface is integrally provided with a holding unit for fixing and holding the light source and the light shielding unit, the number of parts can be reduced, and the light shielding unit and the second reflection for the light source can be reduced. There is no need to position the surface, the assembly can be easily performed, and the amount of heat generated by the light source is small, so that it can be integrally formed with resin.

  When the first reflecting surface, the second reflecting surface, and the light shielding portion are integrally formed, the number of parts is similarly reduced, and the light shielding portion, the first reflecting surface, and the first light shielding portion are reduced with respect to the light source. There is no need to position the second reflecting surface, the assembly can be easily performed, and the amount of heat generated by the light source is small, so that it can be integrally formed with resin.

  The first reflecting surface, the second reflecting surface, and the light shielding portion are integrally formed of a transparent material, and a reflecting film is formed on a surface region corresponding to the first reflecting surface and the second reflecting surface. In addition, when a light-impermeable film is formed on the surface region corresponding to the light-shielding portion, the number of parts can be reduced in the same manner, and the formation of the reflection film and the light-impermeable film can be easily performed. The first and second reflecting surfaces and the light shielding portion can be configured.

  When the first reflecting surface is composed of a composite elliptical surface, the reflected light from the light source can be appropriately guided by the second reflecting surface based on the shape of the first reflecting surface.

  When the lamp is a vehicular lamp, particularly a vehicle headlamp, and the light-shielding portion forms a cut-off corresponding to the light distribution pattern of the passing beam, an LED is used as a light source, and the lamp is small. In addition, a vehicle headlamp without color separation can be configured.

Thus, according to the present invention, with respect to the light emitted forward from the light source composed of the light emitting element, almost all of the light is reflected by the first reflecting surface and incident on the second reflecting surface. , A part of the light is blocked by the light shielding part to form a cut-off, and a cutoff line by the light shielding part is projected forward by the second reflecting surface to form an image at a predetermined distance. The light distribution pattern is obtained. Therefore, since no lens is used for cut-off line imaging, color separation due to chromatic aberration of the lens does not occur, and a uniform color distribution pattern can be obtained as a whole. Since the first reflecting surface can be configured in a small size, the entire lamp can be configured in a small size.
Furthermore, when the first reflecting surface, the second reflecting surface, and the light-shielding portion are configured integrally with the holding portion that holds and holds the light source, the number of parts can be reduced, and positioning between them is unnecessary. As a result, the assembly can be easily performed, and the part cost and the assembly cost can be reduced.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 4.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

1 to 3 show the configuration of a first embodiment of a vehicular lamp to which the present invention is applied.
1 and 2, a vehicular lamp 10 is a headlight of an automobile, and includes a light source 11, a first reflecting surface 12 disposed in front of the light source 11, and a second disposed above the light source 11. And the light shielding portion 14 disposed between the first reflecting surface 12 and the second reflecting surface 13.

The light source 11 is configured as an LED array including a plurality of LEDs (not shown), for example, and the LEDs are arranged in a horizontal direction.
Here, the light source 11 is arranged so that the optical axis 11c passing through the light emission center 11b of the light emitting portion 11a that is long in the horizontal direction extends substantially horizontally toward the front, and is fixedly held by the holding portion 15. It has become.

Each LED is composed of, for example, a blue LED chip and a phosphor layer disposed around the LED so as to emit white light, and the blue light emitted from the blue LED chip is a phosphor in the phosphor layer. Is excited to generate yellow light as excitation light, and white light is emitted to the outside by mixing the yellow light and the blue light from the blue LED chip.
In addition, each said LED may be comprised from the fluorescent substance layer arrange | positioned around the ultraviolet LED chip | tip, for example. In this case, the phosphor in the phosphor layer is excited by ultraviolet light from the ultraviolet LED chip and emits white light. At that time, preferably, the ultraviolet light from the ultraviolet LED chip is absorbed by the phosphor in the phosphor layer, or the ultraviolet light emitted to the outside is blocked so that the ultraviolet light is not emitted to the outside. Is done.
Furthermore, the light emission color of each LED is not limited to white, and other light emission colors may be used.

The first reflecting surface 12 is composed of a spheroidal curved surface, and its long axis 12a is perpendicular to the optical axis 11c, that is, substantially upward from the light emission center 11b of the light emitting portion 11a. The first focal point F <b> 1 is disposed so as to extend and is located near the light emission center 11 b of the light source 11.
The first reflecting surface 12 is formed only on the front side of the long axis 12a, and the upper edge thereof is located at substantially the same height as the second focal point F2.

で与えられる複合楕円面により構成されている。
しかしながら、上記第一の反射面１２は、このような回転楕円面または複合楕円面に限定されることなく、例えば三軸楕円面あるいは自由曲面として構成されていてもよい。 Here, more specifically, the first reflecting surface 12 is a spheroid or the following formula:

It is comprised by the compound ellipse surface given by.
However, the first reflecting surface 12 is not limited to such a spheroidal surface or a composite ellipsoidal surface, and may be configured as a triaxial elliptical surface or a free-form surface, for example.

The second reflecting surface 13 is configured by a concave paraboloidal curved surface toward the front, and its axis 13a passes through the second focal point F2 of the first reflecting surface 11 and the light. It is arranged so as to extend parallel to the axis 11c and so that its focal point F is located in the vicinity of the second focal point F2 of the first reflecting surface 11, that is, in the vicinity of the light emission center 11b of the light source 11.
The second reflecting surface 13 is formed only above the axis 13a.

  Here, the second reflecting surface 13 is configured as a paraboloid in principle, but is configured as a free-form surface as long as it is formed in a concave shape toward the front and has a focusing action. May be.

At least the surface of the light-shielding portion 14 is made of an opaque material, and the upper edge 14a thereof is in the vicinity of the second focal point F2 of the first reflecting surface 12, that is, the focal point F of the second reflecting surface 13. It is arranged so that it is located in the vicinity. In the illustrated case, the light shielding portion 14 is configured as a part of the holding portion 15 for fixing and holding the light source 11 described above.
The upper edge 14a extending in the horizontal direction is formed in an appropriate shape, so that a part of the light reflected by the first reflecting surface 12 and directed to the second reflecting surface 13 is blocked, so-called A light distribution pattern of light that is reflected by the second reflecting surface 13 and projected by forming a cut-off is a desired light distribution pattern, for example, a light distribution pattern of a low beam.

Here, as shown in FIG. 3, the second reflecting surface 13 is integrated with each other by, for example, integral molding with a resin material, etc. with respect to the holding portion 15 that holds the light source 11 fixed (including the light shielding portion 14). It is configured.
In this case, the second reflecting surface 13 is constituted by a reflecting film formed on the surface of the molded part by vapor deposition or the like.

The vehicular lamp 10 according to the embodiment of the present invention is configured as described above, and the light emitted from the light emitting unit 11a is emitted from each LED constituting the light emitting unit 11a of the light source 11 by being fed with power. The light is reflected by the first reflecting surface 12 and travels toward the second focal point F2.
At that time, since the light emitting portion 11a has a substantially hemispherical illuminance distribution toward the front, the light emitted from the light emitting portion 11a transmits almost all the light flux toward the second reflecting surface 13. It will be reflected.

Then, the light that has passed through the second focal point F <b> 2 is reflected by the second reflecting surface 13, and is emitted toward the front while being condensed based on the curvature of the second reflecting surface 13. become.
At that time, a part of the light traveling from the first reflecting surface 12 toward the second reflecting surface 13 is blocked by the light-shielding portion 14 to form a cut-off, and the image is reflected on the second reflecting surface. Since the image is projected forward by 13 and imaged at a predetermined distance, for example, a light distribution pattern of a low beam is provided.

In this case, the lens is not used for the cut-off line imaging, and the second reflecting surface 13 is used. Therefore, color separation due to the chromatic aberration of the lens does not occur, and the entire white color is uniform. A light distribution pattern is obtained.
In addition, since the first reflecting surface 12 is formed in a vertically long shape and guides reflected light obliquely upward, the first reflecting surface 12 itself is configured in a small size, As a result, the entire vehicular lamp 10 can be made compact.

  In addition, since the second reflecting surface 13 and the holding portion 15 are integrally formed by integral molding, the second reflecting surface 13 and the holding portion 15 can be easily configured at low cost, and the light-shielding portion 14 is provided on the holding portion 15. Coupled with being configured as a part, the second reflecting surface 13 is accurately positioned with respect to the light emission center 11b, the optical axis 11c, and the light shielding portion 14 of the light source 11, so that positioning work is not required and assembly is performed. Can be easily performed.

  Thus, according to the vehicular lamp 10 according to the present invention, the light from the light emitting portion 11a of the light source 11 is reflected by the first reflecting surface 12, and the second focal point F2, that is, the second reflecting surface 13 is reflected. Is irradiated toward the vicinity of the focal point F, reflected by the second reflecting surface 13, converged toward the front and irradiated, and part of the light traveling from the first reflecting surface 12 toward the second reflecting surface 13 Is blocked by the light-shielding portion 14, and the shape of the upper edge 14 a of the light-shielding portion 14, that is, the cut-off line, is imaged at a predetermined distance in front by the second reflecting surface 13, so A predetermined light distribution pattern, for example, a light distribution pattern of a passing beam can be formed without causing separation.

FIG. 4 shows a schematic cross-sectional view of a second embodiment of a vehicular lamp according to the present invention.
In FIG. 4, the vehicular lamp 20 has substantially the same configuration as the vehicular lamp 10 shown in FIG. 1 and FIG. 2, but the first reflecting surface 12 and the second reflecting surface 13 form the light shielding portion 14. The holding part 15 is different in that the holding part 15 is integrally formed from a transparent material such as acrylic resin, PC resin, or glass.
Here, the first reflective surface 12 and the second reflective surface 13 can be configured by forming a reflective film on the corresponding surface region of a molded part made of a transparent material by vapor deposition or the like, It can be constructed by masking a light-impermeable material over the corresponding area of the molded part.

  According to the vehicular lamp 20 having such a configuration, the first and second reflecting surfaces 12 and 13 function in the same manner as the vehicular lamp 10 shown in FIGS. By being configured integrally with the light-shielding portion 14, the number of parts can be reduced, assembly is easily performed, and the first reflecting surface 12 and the second reflecting surface 13 are accurately positioned with respect to the light source 11. Therefore, it is not necessary to perform positioning at the time of assembly, and the assembly can be performed easily.

In the above-described embodiment, an LED is used as a light emitting element constituting the light source 11, but is not limited thereto, and may be a small light source using another type of light emitting element such as a laser element. .
Moreover, in embodiment mentioned above, although the vehicle lamps 10 and 20 as a headlamp to which this invention is applied are demonstrated, it is not restricted to this, For example, the auxiliary headlamp using the same small light source It is apparent that the present invention can be applied to other types of vehicle lamps such as stop lamps, and other lamps for general lighting.

It is a schematic side view which shows the structure of 1st embodiment of the vehicle lamp by this invention. It is a schematic front view of the vehicle lamp of FIG. It is a schematic sectional drawing of the vehicle lamp of FIG. It is a schematic sectional drawing similar to FIG. 3 which shows the structure of 2nd embodiment of the vehicle lamp by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle lamp 11 Light source 11a Light emission part 11b Light emission center 11c Optical axis 12 1st reflective surface 12a Long axis 13 Second reflective surface 13a Axis 14 Light-shielding part 14a Upper edge 15 Holding part 20 Vehicle lamp

Claims (6)

A light source comprising at least one light emitting element and having an optical axis extending substantially horizontally forward;
The first focal point is located near the light emission center of the light source, and the second focal point is from the first focal point, so that the light emitted forward from the light source is reflected vertically upward and obliquely backward. A first reflecting surface of a spheroidal surface system that is located above and perpendicular to the optical axis and is formed only substantially in front of the central axis;
The focal point is positioned near the second focal position of the first reflective surface so that the light from the first reflective surface is reflected forward, and the optical axis thereof is that of the first reflective surface. A second reflecting surface of a concave paraboloidal system that is concave forward and intersects at an angle of 90 degrees or less with respect to the vertical major axis;
A part of the light from the first reflecting surface to the second reflecting surface is blocked by the upper edge to form a cut-off suitable for a predetermined light distribution pattern. A light-shielding part arranged near the second focal point;
Including,
A lamp characterized by that.   2. The lamp according to claim 1, wherein the second reflecting surface integrally includes a holding portion for fixing and holding a light source and the light shielding portion.   The lamp according to claim 1, wherein the first reflection surface, the second reflection surface, and the light shielding portion are integrally formed.   The first reflecting surface, the second reflecting surface, and the light shielding portion are integrally formed of a transparent material, and a reflecting film is formed on a surface region corresponding to the first reflecting surface and the second reflecting surface. The lamp according to claim 1, wherein an opaque film is formed in a surface region corresponding to the light shielding portion.   The lamp according to any one of claims 1 to 4, wherein the first reflecting surface is composed of a composite elliptical surface. The lamp is a vehicle lamp, particularly a vehicle headlamp,
The lamp according to any one of claims 1 to 5, wherein the light shielding portion forms a cut-off corresponding to a light distribution pattern of a passing beam.

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