JP6087525B2 - Vehicle lighting - Google Patents

Description

  The present invention relates to a vehicular lamp using a laser light source.

  When a laser light source is incident on a surface with fine unevenness of an object, light beams reflected from the uneven surface interfere with each other to cause an interference phenomenon called speckle. Speckles appear as bright and dark spots that shine brightly in the eyes of humans, and are too conspicuous and annoying, so they become noise for illumination purposes. Patent Document 1 proposes a technique for reducing speckle noise in an illumination device.

  On the other hand, in a vehicle lamp, a technique that adapts to the nature of a person who naturally follows a moving object with eyes and uses the speckle-specific brightness has been proposed. For example, Patent Document 2 describes a vehicular lamp that excites a phosphor with light from a laser light source and forms a high-luminance passing beam light distribution pattern or a traveling beam light distribution pattern by light emission from the phosphor. Has been.

JP 2005-345232 A JP 2011-198560 A

  However, according to the conventional vehicular lamp, the phosphor is caused to emit light by the light from the laser light source. Therefore, the phosphor becomes early due to the difference in the expansion coefficient between the phosphor and the support substrate due to repeated turning on and off. There was a problem of peeling off. In order to prevent peeling, a technique for supporting a phosphor via an interference agent layer has also been proposed. However, in this case, there is a disadvantage that the cost of an optical system using speckle is high.

  Therefore, an object of the present invention is to provide a vehicular lamp with high visibility that can effectively use speckle-specific brightness with an inexpensive configuration.

In order to solve the above problems, the present invention provides the following vehicular lamp.
(1) A vehicular lamp including a laser light source and a light guide that transmits laser light from the laser light source, the light guide including a scattering medium that scatters the laser light.
Here, as the scattering medium, a solid, liquid, gas or other substance in the light guide that exhibits the scattering action of laser light, bubbles in the light guide, cracks, spaces, irregularities on the surface of the light guide, grooves, Although a protrusion, a fine shape part, etc. can be illustrated, Preferably the following media can be used.

(2) The vehicular lamp, wherein the scattering medium includes scattering particles mixed in the light guide.
Scattered particles include inorganic fine particles such as titanium oxide, silica and alumina, and fine resin particles such as nylon, polystyrene, polyethylene, polyester and silicone resin, as well as calcium carbonate, cellulose, clay, flour, water-soluble starch, etc. These fine powders can also be used.

(3) A vehicular lamp characterized in that scattering particles are distributed in a regular and dense state in a light guide.

(4) The vehicular lamp, wherein the scattering medium includes a minute interface that totally reflects the laser light in the light guide.

(5) The laser light source includes a plurality of light emitting elements that emit laser beams of different colors, and includes a scanning mirror mechanism that mixes laser beams of a plurality of colors between the laser light source and the light guide. Vehicle lamp.

  According to the vehicular lamp of the present invention, the scattering medium is included in the light guide that transmits the laser light. Therefore, the speckle-specific direct optical system including the laser light source and the light guide is used. The effective use of the brightness of the lamp increases the visibility of the lamp, increases its presence, and contributes to the improvement of safety.

It is a front view of the vehicular lamp which shows Example 1 of the present invention. It is a vertical sectional view of the vehicular lamp of FIG. It is a front view of the vehicle lamp which shows Example 2 of this invention. FIG. 4 is a vertical sectional view of the vehicle lamp in FIG. 3. It is a perspective view of the vehicle lamp which shows the example of a change of this invention. It is a perspective view of the vehicle lamp which shows another modified example of this invention. It is a perspective view of the vehicle lamp which shows the other modification of this invention.

  Hereinafter, several embodiments embodying the present invention will be described with reference to the drawings. In each embodiment, the same or similar components are shown with the same reference numerals in the drawings.

  1 and 2 show Embodiment 1 of the present invention. The vehicular lamp 11 according to the first embodiment is a rear combination lamp installed at the rear part of a vehicle body, and includes a backup lamp 15, a tail / stop lamp 16, a turn in a lamp chamber 14 between the lamp body 12 and the front cover 13. A signal lamp 17 is provided.

  The backup lamp 15 includes a white laser light source 18A and a light guide 19A that transmits the laser light and emits white light. The backup lamp 15 includes a red laser light source 18B and a light guide 19B that transmits the laser light and emits red light. The turn signal lamp 17 includes an amber laser light source 18C and a light guide 19C that transmits the laser light and emits amber light.

  Each light guide 19 </ b> A to 19 </ b> C is formed of a translucent resin material into a plate shape or a cylindrical shape, and scattering particles 20 that scatter laser light are mixed in the translucent resin material. The scattering particles 20 are, for example, titanium oxide particles, and are distributed in a regular and dense state in the light guides 19A to 19C. For example, the light guide 19 in FIG. 2 is distributed so that the scattering particles 20 are coarser toward the center and denser toward the outer periphery in order to increase the brightness of the outline.

  Therefore, according to the vehicular lamp 11 of the first embodiment, in particular, in the rear combination lamp having a function as a marker lamp, the specifications of the light guides 19 to C with the light from the three color laser light sources 18A to 18C are provided. It can give a distinctive sparkle, improve visibility from the rear vehicle, and increase the presence of the host vehicle. In addition, since the three lamps 15, 16, and 17 having different functions are each composed of two parts, a laser light source 18 and a light guide 19, a conventional indirect optical system that emits a phosphor in the middle of the optical path In comparison, there is also an advantage that the configuration for obtaining the speckle effect can be simplified.

  3 and 4 show a second embodiment of the present invention. The vehicular lamp 21 of the second embodiment is equipped with a scanning mirror mechanism 22 that mixes red, green, and blue laser beams in a rear combination lamp. The scanning mirror mechanism 22 includes a light source unit 23, a scanning mirror 24, and a controller 25.

  The light source unit 23 is provided with three-color laser light sources 26R, 26G, and 26B and optical systems 27R, 27G, and 27B corresponding to the respective light sources. As the scanning mirror 24, a MEMS mirror, a galvanometer mirror, a polygon mirror, or the like is used. The controller 25 controls the turning on / off of each laser light source 26 and the direction of the scanning mirror 24 synchronously. The scanning mirror mechanism 22 is configured to generate white, red, and amber laser light with the light source unit 23 and reflect the laser light toward the light guide 28 with the scanning mirror 24.

  The light guide 28 includes a first Fresnel lens portion 29A that transmits white laser light for a backup lamp on a translucent resin substrate, and a second Fresnel lens portion 29B that transmits red laser light for a tail / stop lamp. And the third Fresnel lens portion 29C that transmits the amber laser light for the turn signal lamp is integrally formed. And the scattering particle | grains 20 for scattering a laser beam are mixed in the translucent resin material of each Fresnel lens part 29, and it distributes in the state with regular density.

  Therefore, according to the vehicular lamp 21 of the second embodiment, in addition to the same effect as that of the rear combination lamp of the first embodiment, in particular, by rotating or vibrating the single scanning mirror 24, the three colors of laser beams can be transmitted at high speed. And the light can be emitted as parallel light from the Fresnel lens portion 29 corresponding to each color.

The present invention is not limited to the above embodiment, and can be implemented by appropriately changing the shape and configuration of each part without departing from the spirit of the invention, as exemplified below.
(1) As shown in FIG. 5, a plurality of laser light sources 32 are combined with one light guide 31, and the density of the scattering particles 20 is changed according to the number and orientation of the laser light sources 32.

(2) As shown in FIG. 6, the light guide 31 is formed in a columnar shape, the laser light source 32 is disposed on the end face thereof, and the density of the scattering particles 20 is determined in the longitudinal direction of the light guide 31 according to the light distribution pattern To change regularly.

(3) As shown in FIG. 7, the light guide 31 is formed into a donut shape with a light-transmitting resin material, and a minute interface serving as a scattering medium is formed in the light guide 31 with the light-transmitting resin material. A part of the laser light from the light source 32 is totally reflected at the minute interface and is enclosed in the light guide 31, and the remaining laser light is scattered by the scattering particles 20, and leaked to the outside of the light guide 31. Configure to emit.

11 Vehicle Lamp (Example 1)
18 Laser light 19 Light guide 20 Scattered particle 21 Vehicle lamp (Example 2)
22 Scanning mirror mechanism 26 Laser light 28 Light guide 29 Fresnel lens part

Claims (4)

A laser light source and a light guide that transmits laser light from the laser light source, the light guide includes a scattering medium that scatters the laser light;
The laser light source is arranged so that laser light enters from one end surface of the light guide, and the light guide is configured to emit scattered light from the scattering medium in a direction substantially perpendicular to the optical axis of the laser light source ,
The scattering medium includes scattering particles mixed in the light guide, and the scattering particles are distributed so as to be coarser in the center of the light guide and denser in the outer periphery of the light guide. Vehicle lamp.   The vehicular lamp according to claim 1, wherein the scattering medium includes a minute interface that totally reflects laser light in the light guide.   2. The scanning laser mechanism according to claim 1, wherein the laser light source includes a plurality of light emitting elements that emit laser beams of different colors, and includes a scanning mirror mechanism that mixes laser beams of a plurality of colors between the laser light source and the light guide. Vehicle lamp.   A laser light source and a light guide that transmits laser light from the laser light source, the light guide includes a scattering medium that scatters the laser light;
The laser light source is arranged so that laser light enters from one end surface of the light guide, and the light guide is configured to emit scattered light from the scattering medium in a direction substantially perpendicular to the optical axis of the laser light source,
A vehicular lamp characterized in that the scattering medium includes scattering particles mixed in a light guide, and the scattering particles are distributed so as to be coarser as they are closer to the laser light source and denser as they are farther from the laser light source.

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