Vehicle lamp

Patent metadata

Field	Value
Publication number	US-11092307-B2
Application number	US-201916966579-A
Country	US
Kind code	B2
Filing date	Feb 7, 2019
Priority date	Feb 14, 2018
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

A vehicle headlamp (1) includes: a light source (52R, 52G, 52B) that emits light having a predetermined wavelength; a light distribution pattern forming optical system (56R, 56G, 56B) that includes a collimator lens (53R, 53G, 53B) and a diffraction grating (54R, 54G, 54B) that change a traveling direction of at least some of pieces of light emitted from the light source (52R, 52G, 52B), and emits light (LR, LG, LB) having a predetermined light distribution pattern; and a vibration imparting unit (57R, 57G, 57B) that relatively vibrates the light source (52R, 52G, 52B) and the diffraction grating (54R, 54G, 54B).

First claim

The invention claimed is:

1. A vehicle lamp comprising:
a light source that emits light having a predetermined wavelength;
a light distribution pattern forming optical system that includes an optical element that changes a traveling direction of at least some of pieces of the light emitted from the light source, and emits light having a predetermined light distribution pattern; and
a vibration imparting unit that relatively vibrates the light source and the optical element;
wherein the vibration imparting unit is a vibrator which vibrates the light source or the optical element, and an amplitude of vibration imparted by the vibration imparting unit varies.

2. The vehicle lamp according to claim 1 ,
wherein the vibration imparting unit vibrates the optical element.

3. The vehicle lamp according to claim 2 ,
wherein the optical element is a diffraction grating.

4. The vehicle lamp according to claim 2 ,
wherein the vibration imparting unit imparts vibration to the optical element in two or more directions.

5. The vehicle lamp according to claim 2 ,
wherein a frequency of vibration imparted by the vibration imparting unit is 15 Hz or higher.

6. The vehicle lamp according to claim 1 ,
wherein the vibration imparting unit vibrates the light source.

7. The vehicle lamp according to claim 1 , wherein
the optical element is a set of a plurality of diffraction gratings, each of the plurality of diffraction gratings having a same diffraction grating pattern,
the vibration imparting unit vibrates the diffraction gratings, and
the amplitude of vibration imparted by the vibration imparting unit is larger than a length of a vibration direction of a region having the same diffraction grating pattern in each of the diffraction gratings.

Assignees

• Koito Mfg Co Ltd

Inventors

• Kito Masanori

Classifications

• F21S41/635

  by moving refractors, filters or transparent cover plates · CPC title

• F21V9/00

  Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters (coloured shades F21V1/00; elements characterised by cooling arrangements F21V29/502) · CPC title

• G02B2005/1804

  Transmission gratings · CPC title

• F21S41/285

  Refractors, transparent cover plates, light guides or filters not provided in groups F21S41/24 - F21S41/2805 · CPC title

• G02B27/48

  Laser speckle optics · CPC title