Headlight device and vehicle device using same

Patent metadata

Field	Value
Publication number	US-2017144591-A1
Application number	US-201415315668-A
Country	US
Kind code	A1
Filing date	Jun 18, 2014
Priority date	Jun 18, 2014
Publication date	May 25, 2017
Grant date	—

Abstract

A headlight device ( 1 ) having a projection function includes a light source device ( 2 ), a lighting optical system ( 3 ), an image display element ( 4 ), an image signal controller ( 6 ), and a projection optical system ( 5 ). The projection optical system ( 5 ) includes a coaxial lens system ( 11 ) having a refractive action, a free-form surface lens ( 12 ), and a free-form surface mirror ( 13 ) from the image display element ( 4 ) side. In this way, an image that can be readily visually recognized by a driver or a pedestrian may be projected onto a road.

First claim

1 . A headlight device that projects an image onto a road surface, the headlight device comprising:
a light source device; a lighting optical system that condenses light emitted from the light source device; an image display element that forms an optical image by receiving the light condensed by the lighting optical system; an image signal controller that supplies an image signal for forming the optical image to the image display element; and a projection optical system that enlarges the optical image formed by the image display element and projects the enlarged optical image onto the road surface, wherein the projection optical system includes a coaxial lens system having a refractive action, a free-form surface lens, and a free-form surface mirror from a side of the image display element.

2 . The headlight device according to claim 1 , wherein an inequality of
a projection ratio=Z 0 /Y 0 <0.1 is satisfied when a length of a perpendicular line drawn from an emission position of the projection optical system to the road surface onto which the image is projected is set to Z 0 , and a length of a long side of a projection image on the road surface is set to Y 0 .

3 . The headlight device according to claim 1 , wherein an inequality of
an aspect ratio=Y 0 /X 0 >2 is satisfied when a vertical size of a projection image on the road surface viewed from the headlight device is set to Y 0 , and a horizontal size of the projection image is set to X 0 .

4 . A vehicle device equipped with the headlight device claim 1 , wherein the image signal controller includes
an image signal generator that generates a predetermined image signal according to operation information of a driver, and supplies the generated image signal to the image display element, and a display aspect ratio changing unit that determines an aspect ratio of the projection image according to running velocity information of the vehicle device, and changes the image signal supplied to the image display element.

5 . The vehicle device according to claim 4 , wherein, when an aspect ratio of the projection image viewed from the driver is set to [a vertical size of the projection image viewed from the driver]/[a horizontal size of the projection image viewed from the driver], the display aspect ratio changing unit changes the aspect ratio of the projection image viewed from the driver to a smaller value when a running velocity of the vehicle device is slower than a predetermined velocity.

6 . The vehicle device according to claim 5 , wherein the changing of the aspect ratio of the projection image viewed from the driver to the smaller value by the display aspect ratio changing unit corresponds to a case in which an image signal indicating a right turn sign or a left turn sign is generated as the projection image by the image signal generator.

Assignees

• Hitachi Maxell

Inventors

• Yatsu Masahiko

Classifications

• H04N9/3188

  Scale or resolution adjustment (scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391) · CPC title

• G03B21/2066

  Reflectors in illumination beam (in projection beam G03B21/28) · CPC title

• G09G2340/045

  Zooming at least part of an image, i.e. enlarging it or shrinking it · CPC title

• G03B21/208

  Homogenising, shaping of the illumination light · CPC title

• G09G2380/10

  Automotive applications · CPC title