HEADLAMP FOR VEHICLES

• US 20170276980A1
• Filed: 08/19/2015
• Published: 09/28/2017
• Est. Priority Date: 09/23/2014
• Status: Abandoned Application

• Current Assignee: Hella Gmbh & Co. Kgaa (Forvia SE)
• Original Assignee: Hella KGaA Hueck & Company
• Inventors: Kauschke, Rainer, Wilks, Carsten, Schmidt, Christian
• Application Number:
  US15/506,136
• Publication Number:
  US 20170276980A1
• Time in Patent Office: Days
• CPC Class Codes: B60Q 1/14 having dimming means
• CPC Class Codes: F21S 41/135 Polarised
• CPC Class Codes: F21S 41/147 the main emission direction of the LED being angled to the optical axis of the illuminating device
• CPC Class Codes: F21S 41/148 the main emission direction of the LED being perpendicular to the optical axis
• CPC Class Codes: F21S 41/25 Projection lenses
• CPC Class Codes: F21S 41/335 with continuity at the junction between adjacent areas
• CPC Class Codes: F21S 41/36 Combinations of two or more separate reflectors
• CPC Class Codes: F21S 41/365 successively reflecting the light
• CPC Class Codes: F21S 41/37 characterised by their material, surface treatment or coatings
• CPC Class Codes: F21S 41/645 by electro-optic means, e.g. liquid crystal or electrochromic devices
• CPC Class Codes: F21V 7/0025 Combination of two or more reflectors for a single light source array of reflectors for a cluster of light sources F21V7/0083
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: G02F 1/13 based on liquid crystals, e.g. single liquid crystal display cells
• CPC Class Codes: G02F 1/1336 Illuminating devices
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133616 Front illuminating devices

Abstract

A headlamp for vehicles having a light source, a lens unit and a liquid crystal shutter arranged between the light source and the lens unit. The liquid crystal shutter includes a multitude of surface areas that can each be controlled to switch the respective surface areas to a transparent or a non-transparent state so that a given light distribution pattern is generated. A polarizing reflector is assigned to the light source, so that a linearly polarized light beam is reflected in the direction of the liquid crystal shutter.

Claims

1. A headlamp for vehicles comprising:

a light source;

a lens unit and

a liquid crystal shutter arranged between the light source and the lens unit

a polarizing reflector assigned to the light source, so that a linearly polarized light beam is reflected in direction of the liquid crystal shutter;

wherein the liquid crystal shutter comprising a multitude of surface areas that can each be controlled to switch the respective surface areas to a transparent or a non-transparent state so that a given light distribution pattern is generated.

2. The headlamp according to claim 1, wherein the polarizing reflector has several reflector surfaces being arranged relative to the light source in a manner that light beams emitted by the light source hit the reflector surfaces under a Brewster angle (Θ

b).

3. The headlamp according to claim 1 wherein the polarizing reflector is embodied in an onion-shaped manner and that the light source is arranged perpendicular to a main beam direction (H) of the headlamp or at an acute angle against the main beam direction (H).

4. The headlamp according to claim 1, wherein the polarizing reflector is embodied in a transparent or partially transparent manner, so that a first partial light beam is let through as a polarized light beam in the direction of the liquid crystal shutter and a second partial light beam is let through as an unpolarized light beam in the direction of a second reflector on which the second partial light beam is reflected past the liquid crystal shutter for the generation of a static basic light distribution pattern (GVL).

5. The headlamp according to claim 1, wherein a polarizing beam splitter is arranged between the polarizing reflector and the liquid crystal shutter, which divides a further partial light beam of the light source into a first polarized light beam which is directed directly to the liquid crystal shutter, and a second polarized light beam which is redirected to the liquid crystal shutter via a further reflector and a quarter-wave layer.

6. The headlamp according to claim 5, wherein the quarter-wave layer is integrated in the further reflector.

7. The headlamp according to claim 5, wherein the polarizing beam splitter is embodied in a stepped manner.

8. The headlamp according to claim 1, wherein several dishes of the polarizing reflectors can be arranged at right angles relative to an optical axis in a staggered manner, the polarizing reflectors being embodied in an at least partially transparent manner.

9. The headlamp according to claim 1, wherein the light source is arranged relative to the polarizing reflector so that due to the angle of incidence 4% to 70%, preferably 8% of the light beam is reflected on the reflector surfaces of the polarizing reflector.

10. The headlamp according to claim 1, wherein pixels of the liquid crystal shutter can be controlled depending on sensor data provided by a traffic space detect unit to generate the given light distribution pattern comprising a non-dazzling area in which a further traffic object is present.