Camera having a through the lens pixel illuminator

• US 7,355,648 B1
• Filed: 07/09/2000
• Issued: 04/08/2008
• Est. Priority Date: 02/16/1999
• Status: Expired due to Fees

• Current Assignee: Microsoft International Holdings BV (Microsoft Corporation)
• Original Assignee: 3DV Systems Ltd. (Microsoft Corporation)
• Inventors: Braun, Ori J., Yahav, Giora
• Primary Examiner(s): Ho; Tuan
• Assistant Examiner(s): LE, TUAN H
• Application Number:
  US10/332,643
• Time in Patent Office: 2,830 Days
• Field of Search: 348370-372, 348/136, 348/143, 348/152, 348/61, 348/135, 348/169, 348268-271, 396/61, 396/106, 396/109, 396/164, 396/100, 396/182, 382/103, 362/11, 362/276, 362464-466
• US Class Current: 348/370
• CPC Class Codes: B60Q 2400/50 Projected symbol or information, e.g. onto the road or car body
• CPC Class Codes: B60Q 9/008 for anti-collision purposes
• CPC Class Codes: F21S 41/141 Light emitting diodes [LED]
• 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 41/663 by switching light sources by switching incandescent light sources F21S41/162
• CPC Class Codes: G01C 11/025 by scanning the object
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 17/18 wherein range gates are used
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4812 transmitted and received beams following a coaxial path
• CPC Class Codes: G01S 7/51 Display arrangements
• CPC Class Codes: G02B 7/32 using active means, e.g. light emitter including both an active and a passive focus detecting device G02B7/285; using ultrasound G02B7/40
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means

Abstract

A camera comprising: a photosurface comprising light sensitive pixels that generate signals responsive to light incident thereon and optics that focus an image of a scene onto the photosurface; and an illumination system for illuminating the scene, the illumination system comprising: an illuminator having a plurality of substantially contiguous, independently controllable light providing regions; optics that focuses an image or the illuminator on the scene so that light from the illuminator illuminates substantially all of and substantially only the field of view of the camera; and a controller that controls light provided by each light providing region.

Claims

1. A camera comprising:

a photosurface comprising light sensitive pixels that generate signals responsive to light incident thereon and optics that focus an image of a scene onto the photosurface; and

an illumination system for illuminating the scene with light that is reflected from the scene and imaged on the photosurface by the optics, the illumination system comprising;

an illuminator having a plurality of substantially contiguous, independently controllable light providing regions;

optics that focuses an image of the illuminator on the scene so that light from the illuminator illuminates substantially all of and substantially only the field of view of the camera; and

a controller capable of controlling the light providing regions to adjust lighting to the scene responsive to each of a plurality of selectable lighting adjustment procedures,

wherein the controller adjusts the distribution of light responsive to an image acquired by the camera.

2. A camera according to claim 1 wherein each light providing region is controllable to provide one or more of R, G or B light.

3. A camera according to claim 2 wherein responsive to a lighting adjustment procedure the controller controls intensity of R, G or B light provided by each light providing region so as to control hue, saturation or intensity of light illuminating a region of the scene independently of hue saturation and intensity of light illuminating other regions of the scene.

4. A camera according to claim 2 wherein responsive to a lighting adjustment procedure the controller controls light provided by at least one light providing region to control an intensity distribution of R, G or B light reflected by the scene that is incident on pixels of the photosurface.

5. A camera according to claim 1 wherein each light providing region is controllable to provide white light.

6. A camera according to claim 1 wherein the illuminator is boresighted with the photosurface so that a virtual image of the illuminator is located at the photosurface and optics that image the scene on the photosurface image the illuminator on the scene.

7. A camera according to claim 6 wherein a virtual image of the illuminator is substantially coincident with the photosurface.

8. A camera according to claim 1 wherein light from each of the light providing regions that is reflected from the scene is imaged on a different group of contiguous pixels in the photosurface.

9. A camera according to claim 1 wherein light from each of the light providing regions that is reflected from the scene and imaged by the camera is imaged on a region of the photosurface having a size substantially equal to the size of a pixel in the photosurface.

10. A camera according to claim 9 wherein the region on which the light is imaged is located substantially within the area of a pixel on the photosurface.

11. A camera according to claim 1 wherein the regions of the photosurface on which light from at least two adjacent light providing regions of the illuminator is imaged overlap.

12. A camera according to claim 1 wherein there is substantially little overlap of regions of the photosurface on which light from adjacent light providing regions of the illuminator is imaged.

13. A camera according to claim 1 wherein light from a plurality of the light providing regions that is reflected from the scene and imaged by the camera is imaged on a same region of the photosurface having a size substantially equal to the size of a pixel in the photosurface.

14. A camera according to claim 13 wherein the region on which the light from the plurality of light providing regions is imaged is located substantially within the area of a pixel on the photosurface.

15. A camera according to claim 1 wherein responsive to a lighting adjustment procedure the controller controls intensity of light provided by each light providing region so as to control intensity of light illuminating a region of the scene illuminated by light from the light providing region independently of intensity of light illuminating other regions of the scene.

16. A camera according to claim 1 wherein responsive to a lighting adjustment procedure the controller controls light provided by at least one light providing region to control an intensity distribution of light reflected by the scene that is incident on pixels of the photosurface.

17. A camera according to claim 1 wherein the controller receives signals generated by each pixel responsive to light incident on the pixel and controls light provided by at least one of the light providing regions responsive to the signals to adjust illumination of the scene.

18. A camera according to claim 17 wherein responsive to a lighting adjustment procedure the controller controls light provided by at least one light providing region to decrease intensity of light reaching the camera from a region of the scene for which intensity of light incident on a pixel that images the region is greater than a predetermined maximum intensity.

19. A camera according to claim 17 wherein responsive to a lighting adjustment procedure the controller controls light provided by at least one light providing region to increase intensity of light reaching the camera from a region of the scene for which intensity of light incident on a pixel that images the region is less than a predetermined minimum intensity.

20. A camera according to claim 1 wherein the camera comprises a user operated input terminal to transmit instructions to the controller and wherein the controller controls light from at least one of the light providing regions responsive to the instructions to adjust illumination of the scene.

21. A camera according to claim 20 wherein the input terminal comprises a display screen.

22. A camera according to claim 21 wherein the controller generates a preview of an image of the scene being imaged by the camera on the screen responsive to signals that it receives from the pixels.

23. A camera according to claim 22 and comprising a selector controllable to select an object or region in the preview.

24. A camera according to claim 23 wherein the controller controls light provided by light providing regions responsive to the selected region or object.

25. A camera according to claim 21 wherein the controller displays a control panel having control icons on the screen and wherein manipulation of the control icons transmits instructions to the controller.

26. A camera according to claim 1 and comprising a shutter that the controller opens and closes to gate the photosurface on and off.

27. A camera according to claim 26 wherein the controller shutters light from light providing regions so as to radiate at least one pulse of light having a pulse width that illuminates the scene.

28. A camera according to claim 27 wherein the controller gates the photosurface on and off at times responsive to a time at which the at least one light pulse is radiated.

29. A camera according to claim 28 wherein the controller determines a distance to a region of the scene responsive to light reaching a pixel that images the region during a time at which the photosurface is gated on.

30. Apparatus according to claim 1 wherein the controller is capable of controlling the light intensity of light from the light providing regions to provide lighting of the scene which gives a reduced range of intensities of light entering the camera from the scene.

31. A camera comprising:

a photosurface comprising light sensitive pixels that generate signals responsive to light incident thereon and optics that focus an image of a scene onto the photosurface; and

an illumination system for illuminating the scene, the illumination system comprising;

an illuminator having a plurality of substantially contiguous, independently controllable light providing regions;

optics that focuses an image of the illuminator on the scene so that light from the illuminator illuminates substantially all of and substantially only the field of view of the camera;

a shutter controllable to gate the photosurface on and off; and

a controller that shutters light from light providing regions so as to radiate at least one pulse of light having a pulse width that illuminates the scene and controls each light providing region so as to minimize a difference between an amount of light reaching different pixels in the photosurface from the at least one light pulse.

32. A camera according to claim 31 wherein the controller gates the photosurface on and off at times responsive to a time at which the at least one light pulse is radiated.

33. A camera according to claim 32 wherein the controller gates the photosurface off when the illumination system is providing light to illuminate the scene.

34. A camera according to claim 32 wherein the controller determines a distance to a region of the scene responsive to light reaching a pixel that images the region during a time at which the photosurface is gated on.

35. A camera according to claim 31 wherein the at least one light pulse comprises a train of light pulses.

36. A camera according to claim 31 wherein the controller controls light provided by the light providing regions so as to minimize a difference between a predetermined light intensity and intensity of light reaching each pixel in the photosurface from the scene.

37. A camera according to any of claim 31 wherein the controller:

controls the light providing regions to illuminate the scene with substantially uniform illumination;

acquires a first image of the scene under uniform illumination;

determines intensities of light provided by light providing regions for the uniform illumination that minimizes the difference between the light reaching different pixels;

controls the light providing regions to illuminate the scene with a second illumination responsive to the determined intensities;

acquires a second image of the scene under said second illumination;

determines an amount of light reaching each pixel in the second image; and

determines brightness values for a region of the scene responsive to intensity values of said second illumination and amounts of light reaching pixels in said second image.

38. A camera according to claim 37 wherein the controller controls the camera to acquire the second image using a brightness acquisition range limited to the range of brightness values in the image.

39. Apparatus according to claim 31 wherein the controller adjusts the distribution of light responsive to an image acquired by the camera.

40. A method for illuminating a scene being imaged by a camera, the camera comprising a photosurface having pixels and optics for imaging the scene on the photosurface, the method comprising:

illuminating the scene with an illuminator comprising a plurality of light providers so that each region of the scene that is imaged on a region of the photosurface comprising at least one pixel but less than all the pixels of the photosurface is illuminated with light provided by at least one light provider that provides light substantially only for the region;

providing a controller capable of controlling the light providers to adjust lighting to the scene responsive to each of a plurality of selectable lighting adjustment procedures and to an image acquired by the camera;

selecting a procedure from the plurality of lighting adjustment procedures responsive to which selected procedure the controller controls the at least one light provider for a region of the scene to adjust illumination of the scene.

41. A method according to claim 40 wherein each light provider is controllable to provide R, G or B light.

42. A method according to claim 40 wherein controlling light providers to adjust lighting responsive to a lighting adjustment procedure comprises controlling the light providers so as to perform a predetermined image processing procedure.

43. A method according to claim 42 wherein the image processing procedure comprises unsharp masking.

44. A method according to claim 42 wherein the image processing procedure comprises sharpening.

45. A method according to claim 42 wherein the image processing procedure comprises smoothing.

46. A method according to claim 42 wherein the image processing procedure comprises histogramic equalization.

47. A method according to claim 40 wherein the light providers are independently controllable and wherein controlling each of the light providing regions comprises controlling each of the light providing regions independently of the other light providing regions.

48. A method according to claim 40 wherein controlling the light providers comprises controlling the light providers to control contrast in an image of the scene provided by the camera.

49. A method according to claim 48 wherein controlling contrast comprises controlling contrast in only a localized region of the image.

50. A method according to claim 40 wherein controlling light providers comprises controlling the light providers to adjust an intensity distribution of light from the scene that is incident on pixels in the photosurface.

51. A method according to claim 50 wherein adjusting an intensity distribution comprises controlling a parameter of the intensity distribution.

52. A method according to claim 40 wherein the at least one pixel is a single pixel.

53. A method according to claim 40 and comprising boresighting the illuminator so that a virtual image of the illuminator is located substantially at the photosurface.

54. A method according to claim 53 wherein the virtual image of the illuminator is substantially coincident with the photosurface.

55. A method according to claim 54 wherein a virtual image of each light provider is located within a different group of contiguous pixels on the photosurface.

56. A method according to claim 54 wherein a virtual image of each light provider is located substantially within a corresponding single pixel.

57. A method according to claim 54 wherein a virtual image of a plurality of light providers is located substantially within a corresponding single pixel.

58. A method of imaging, comprising:

illuminating at least a portion of a scene with substantially uniform lighting;

determining a spatially varying illumination that reduces the variability of brightness values of the at least portion of the scene;

illuminating the at least portion with said varying illumination;

acquiring a second image of the at least portion, said second image having brightness values for areas thereof; and

determining the brightness values of the scene under uniform illumination from the brightness values and the varying values of the illumination.

59. A method according to claim 58 wherein acquiring the second image comprises acquiring the images using a brightness acquisition range limited to the range of brightness values in the image.

60. A camera comprising:

a photosurface responsive to light incident thereon and optics that focus an image of a scene onto the photosurface; and

an illumination system that illuminates the scene with light that is reflected from the scene and imaged on the photosurface by the optics, the illumination system comprising;

an illuminator having a plurality of substantially contiguous, independently controllable light providing regions;

optics that focuses an image of the illuminator on the scene so that light from the illuminator illuminates the field of view of the camera; and

a controller capable of controlling the light providing regions to adjust lighting to the scene responsive to an image acquired by the camera.