Lighting device for headlights with a phase modulator

• US 10,061,268 B2
• Filed: 12/07/2016
• Issued: 08/28/2018
• Est. Priority Date: 02/07/2012
• Status: Active Grant

• Current Assignee: Envisics Ltd.
• Original Assignee: Envisics Ltd.
• Inventors: Christmas, Jamieson, Collin, Mikael
• Primary Examiner(s): GRAMLING, SEAN P
• Application Number:
  US15/372,337
• Publication Number:
  US 20170080848A1
• Time in Patent Office: 629 Days
• CPC Class Codes: B60Q 1/06 adjustable, e.g. remotely-controlled from inside vehicle B60Q1/05 takes precedence
• CPC Class Codes: B60Q 1/085 due to special conditions, e.g. adverse weather, type of road, badly illuminated road signs or potential dangers B60Q1/10, B60Q1/12, B60Q1/1423 take precedence
• CPC Class Codes: B60Q 1/12 due to steering position
• CPC Class Codes: B60Q 1/16 illuminating the way asymmetrically
• CPC Class Codes: B60Q 2300/056 Special anti-blinding beams, e.g. a standard beam is chopped or moved in order not to blind
• CPC Class Codes: B60Q 2300/122 Steering angle
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/32 Road surface or travel path
• CPC Class Codes: B60Q 2300/322 Road curvature
• CPC Class Codes: B60Q 2300/33 Driving situation
• CPC Class Codes: B60Q 2300/331 characterised by the driving side, e.g. on the left or right hand side
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: B60Q 2300/45 Special conditions, e.g. pedestrians, road signs or potential dangers
• CPC Class Codes: F21S 41/12 characterised by the type of emitted light
• CPC Class Codes: F21S 41/125 Coloured light
• CPC Class Codes: F21S 41/13 Ultraviolet light; Infrared light
• CPC Class Codes: F21S 41/14 characterised by the type of light source
• CPC Class Codes: F21S 41/16 Laser light sources
• CPC Class Codes: F21S 41/25 Projection lenses
• CPC Class Codes: F21S 41/27 Thick lenses
• CPC Class Codes: F21S 41/285 : Refractors, transparent cover plates, light guides or filters not provided in groups F21S41/24-F21S41/28
• CPC Class Codes: F21S 41/60 : characterised by a variable light distribution
• CPC Class Codes: F21S 41/645 : by electro-optic means, e.g. liquid crystal or electrochromic devices
• CPC Class Codes: F21S 43/13 : characterised by the type of light source
• CPC Class Codes: F21S 43/26 : Refractors, transparent cover plates, light guides or filters not provided in groups F21S43/235 - F21S43/255
• CPC Class Codes: G01S 17/89 : for mapping or imaging
• CPC Class Codes: G01S 17/931 : of land vehicles
• CPC Class Codes: G01S 7/4814 : of transmitters alone
• CPC Class Codes: G01S 7/4911 : Transmitters
• CPC Class Codes: G01S 7/4915 : Time delay measurement, e.g. operational details for pixel components signal extraction and conditioning G01S7/493; Phase measurement
• CPC Class Codes: G03H 1/0005 : Adaptation of holography to specific applications holographic optical element G02B5/32; holographic scanner G02B26/106; recognition using holographic mask G06V10/88; holographic memories G11B7/0065, G11C13/042
• CPC Class Codes: G03H 1/02 : Details of features involved during the holographic process; Replication of holograms without interference recording
• CPC Class Codes: G03H 1/2249 : Holobject properties
• CPC Class Codes: G03H 1/2294 : Addressing the hologram to an active spatial light modulator
• CPC Class Codes: G03H 2001/0212 : Light sources or light beam properties G03H1/06, G03H1/24 take precedence; corresponding details, see subgroups of G03H2222/00
• CPC Class Codes: G03H 2001/0216 : Optical components G03H2001/0224, G03H1/0256 take precedence; corresponding details, see subgroups of G03H2223/00
• CPC Class Codes: G03H 2001/0224 : Active addressable light modulator, i.e. Spatial Light Modulator [SLM] corresponding details, see subgroups of G03H2225/00
• CPC Class Codes: G03H 2001/2263 : Multicoloured holobject
• CPC Class Codes: G03H 2001/2271 : RGB holobject
• CPC Class Codes: G03H 2001/2284 : Superimposing the holobject with other visual information
• CPC Class Codes: G03H 2001/2297 : using frame sequential, e.g. for reducing speckle noise
• CPC Class Codes: G03H 2001/306 : Tiled identical sub-holograms
• CPC Class Codes: G03H 2210/20 : 2D object
• CPC Class Codes: G03H 2210/22 : 2D SLM object wherein the object beam is formed of the light modulated by the SLM SLM per se G03H2001/0224
• CPC Class Codes: G03H 2222/16 : Infra Red [IR]
• CPC Class Codes: G03H 2222/17 : White light G03H1/24 takes precedence
• CPC Class Codes: G03H 2223/26 : Means providing optical delay, e.g. for path length matching
• CPC Class Codes: G03H 2223/55 : Arranged at a Fourier plane
• CPC Class Codes: G03H 2225/25 : Optically addressed SLM [OA-SLM]
• CPC Class Codes: G03H 2225/32 : Phase only
• CPC Class Codes: G03H 2225/52 : Reflective modulator
• CPC Class Codes: G03H 2225/61 : for multicolour processing
• CPC Class Codes: G03H 2226/05 : Means for tracking the observer
• CPC Class Codes: G06V 10/145 : Illumination specially adapted for pattern recognition, e.g. using gratings
• CPC Class Codes: G06V 20/56 : exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: G08G 1/16 : Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08

Abstract

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

Claims

1. A lighting device arranged to produce a controllable light beam for illuminating a scene, the device comprising:

an addressable spatial light modulator arranged to provide a dynamically variable phase delay distribution to a beam of incident light;

Fourier optics arranged to receive phase-modulated light from the spatial light modulator and perform a frequency-space transformation upon the received phase-modulated light to form a light distribution in the spatial domain; and

projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam,

wherein the device is arranged to detect a location of a feature of the scene and modify a set of phase delay distributions on the spatial light modulator to provide additional illumination of the feature of the scene.

2. The lighting device of claim 1, wherein the device is arranged to redirect light from one part of the pattern of illumination to another part of the pattern of illumination in order to provide the additional illumination of the feature.

3. The lighting device of claim 1, wherein the device is arranged to redirect light to other parts of the pattern of illumination in order to provide the additional illumination of the feature without loss of light from the system.

4. The lighting device of claim 1, wherein the device is arranged to redirect a programmable amount of light to the feature in order to provide the additional illumination of the feature.

5. The lighting device of claim 1, wherein the feature includes at least one of a sign, an obstacle, or road side information.

6. The lighting device of claim 1, wherein the feature is a corner in a road and approach of the corner is indicated by a GPS navigation system interfaced to the device.

7. The lighting device of claim 1, further comprising a sign recognition system.

8. The lighting device of claim 7, wherein the device is arranged to determine the size and distribution of the additional illumination in response to an input from the sign recognition system.

9. The lighting device of claim 1, further comprising a collision avoidance system.

10. The lighting device of claim 9, wherein the device is arranged to determine the size and distribution of the additional illumination in response to an input from the collision avoidance system.

11. The lighting device of claim 1, wherein the device is arranged to modify the set of phase delay distributions on the spatial light modulator by adding data relating to the additional illumination to the set of phase delay distributions on the spatial light modulator.

12. The lighting device of claim 1, wherein the projection optics magnify the light distribution.

13. The lighting device of claim 1, wherein the phase delay distribution comprises a representation of the pattern of illumination in the Fourier domain.

14. The lighting device of claim 1, wherein the Fourier optics are a Fourier lens.

15. The lighting device of claim 14, wherein the Fourier lens has a short focal length.

16. The lighting device of claim 1, wherein the spatial light modulator is reflective.

17. The lighting device of claim 1, wherein the spatial light modulator is a liquid crystal on silicon device.

18. The lighting device of claim 1, wherein the spatial light modulator is a phase-only spatial light modulator.

19. The lighting device of claim 1, wherein the beam of incident light is at least partially coherent, and wherein the device further comprises a source of the beam of at least partially coherent incident light.

20. A method for producing a controllable light beam for illuminating a scene, the method comprising:

provide a dynamically variable phase delay distribution to a beam of incident light using an addressable spatial light modulator;

performing a frequency-space transformation upon the received phase-modulated light to form a light distribution in the spatial domain; and

projecting the light distribution to form a pattern of illumination as said controllable light beam,

and

detecting a location of a feature of the scene and modify a set of phase delay distributions on the spatial light modulator to provide additional illumination of the feature of the scene.

21. The method of claim 20, wherein the spatial light modulator is a phase-only spatial light modulator.

22. The method of claim 20, wherein the beam of incident light is at least partially coherent.

23. The method of claim 20, wherein providing additional illumination of the feature of the scene comprises redirecting light from one part of the pattern of illumination to another part of the pattern of illumination in order to provide the additional illumination of the feature.