Holographic LIDAR system

• US 10,451,742 B2
• Filed: 02/01/2019
• Issued: 10/22/2019
• Est. Priority Date: 02/07/2012
• Status: Active Grant

• Current Assignee: Envisics Ltd.
• Original Assignee: Envisics Ltd.
• Inventors: Christmas, Jamieson, Masiyano, Dackson, Collin, Mikael
• Primary Examiner(s): Gramling, Sean P
• Application Number:
  US16/265,667
• Publication Number:
  US 20190163125A1
• Time in Patent Office: 263 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 method for performing a light detection and ranging (“

LIDAR”

) measurement on a scene, comprising;

providing a beam of incident light;

illuminating an addressable spatial light modulator with the beam of incident light;

providing, using the spatial light modulator, a selectable phase delay distribution to the beam of incident light with the addressable spatial modulator to provide an exit beam, the phase delay distribution comprising a representation of a pattern of illumination in the Fourier domain;

performing a frequency-space transformation upon the phase-modulated light of the exit beam to form an image in the spatial domain; and

projecting the image in the spatial domain to form a pattern of illumination in space, the pattern of illumination in space illuminating the scene.

2. The method of claim 1, further comprising detecting illumination reflected from the scene.

3. The method of claim 2, wherein the detection of illumination reflected from the scene comprises capturing an image of the scene illuminated with the pattern of illumination in space.

4. The method of claim 3, further comprising comparing the captured image with the projected pattern of illumination.

5. The method of claim 2, further comprising detecting an abnormality in the scene based on the detected illumination.

6. The method of claim 5, wherein detecting the abnormality comprises identifying differences between a detected pattern illumination and a pattern of illumination corresponding to the phase delay distribution.

7. The method of claim 1, wherein the phase delay distribution is selected to illuminate chosen areas of the scene while not illuminating other areas.

8. The method of claim 1, wherein the pattern of illumination in space is in the form of a grid.

9. The method of claim 8, wherein the incident light is infrared.

10. The method of claim 1, wherein the incident light is infrared.

11. The method of claim 1, wherein the incident light is coherent.

12. The method of claim 1, wherein the incident light has a generally planar wavefront.

13. The method of claim 1, wherein the phase-modulated light of the exit beam is a phase-only modulated light.

14. The method of claim 1, wherein the frequency-space transformation is performed using Fourier optics.

15. The method of claim 1, wherein the incident light is coherent and infrared, and further comprising detecting illumination reflected from the scene.

16. A light detection and ranging (“

LIDAR”

) system, the system comprising

a lighting device arranged to produce a controllable light beam for illuminating a scene, the device comprising;

a source of incident light;

an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light from the source, the phase delay distribution comprising a representation of a pattern of illumination in the Fourier domain;

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;

projection optics arranged to project the light distribution to form the pattern of illumination as said controllable light; and

a light detector arranged to detect light reflected from the controllable light beam by the scene.

17. The LIDAR system of claim 16, wherein the source of incident light is a source of incident light having a generally planar wavefront.

18. The LIDAR system of claim 16, wherein the spatial light modulator is a phase-only spatial light modulator.

19. A vehicle comprising the LIDAR system of claim 16.