Wide angle electronic camera with improved peripheral vision

• US 7,893,985 B1
• Filed: 03/15/2005
• Issued: 02/22/2011
• Est. Priority Date: 03/15/2004
• Status: Active Grant

• Current Assignee: Grandeye Limited (Oncam Global Group AG)
• Original Assignee: Grandeye Limited (Oncam Global Group AG)
• Inventors: Kirsch, Michael Benjamin, Ahiska, Yavuz, Davey, Mark Kenneth
• Primary Examiner(s): SELBY, GEVELL V
• Application Number:
  US11/081,080
• Time in Patent Office: 2,170 Days
• Field of Search: 348/222.1, 348/240.99, 348/240.3, 348/335
• US Class Current: 348/335
• CPC Class Codes: H04N 23/58 Means for changing the camera field of view without moving the camera body, e.g. nutating or panning of optics or image sensors

Abstract

The present inventions provide a system and method for a wide angle camera capable of high resolution peripheral vision. A wide angle lens system distorts the image and conveys it to an image sensor, which converts the image to an electronic signal and conveys it to image processing circuitry. The image processing circuitry corrects the distortion or transforms it to human recognizable image forms. In preferred embodiments, the distortion provides greater resolution of regions of interest and more efficient use of the area of the image sensor.

Claims

1. A wide-angle video camera capable of high resolution peripheral vision comprising:

a) a wide-angle optical system which performs radial distortion to provide a distorted non-rectilinear image of a view, in which a peripheral annulus of the image is magnified, and a central area of the image is demagnified, as compared with a fisheye or similar lens with similar field of view and image size;

b) an image sensor which receives said image and converts it to electrical signals suitable for use by an image processing circuit;

c) said image processing circuit transforming the optical distortions introduced by said wide-angle optical system to correct the optical distortions and accordingly output a human viewable image with greater resolution in peripheral regions of interest.

2. The device of claim 1 in which a conventional lens and a specially manufactured parabolic mirror is used to achieve said radial distortion.

3. The device of claim 1 in which said wide-angle camera is a still picture camera.

4. The device of claim 1, wherein said distortion distorts the projected image into substantially the same shape as a non-circular image sensor.

5. The device of claim 1, wherein the distortion modifies the projected image to substantially fit within a defined border of a non-circular image sensor.

6. A wide-angle video camera capable of high resolution peripheral vision comprising:

a) a wide-angle optical system that projects a distorted non-rectilinear image onto a non-circular image sensor, which converts said non-circular image into electrical signals suitable for use by an image processing circuit;

b) said optical system introducing radially asymmetric distortion to project a non-circular image onto said non-circular sensor, said distortion modifying the image of a view to thereby improve the fit of the projected image to the sensor;

c) said image processing circuit transforming optical distortions introduced by said wide angle optical system output a human recognizable image with a greater proportion of the sensor area utilized than if a circular image were projected.

7. The device of claim 6 in which a conventional lens and a specially manufactured parabolic mirror is used to achieve said radial distortion.

8. The device of claim 6 in which said wide-angle camera is a still picture camera.

9. The device of clam 6, further comprising:

a wide-angle optical system which performs combination of radial and asymmetric distortion to magnify the peripheral area of the view.

10. The device of claim 9 in which a combination of a conventional lens and specially manufactured parabolic mirrors is used to achieve said distortion.

11. The device of claim 9 in which said wide-angle camera is a still camera.

12. A method of improving peripheral resolution of a captured image, comprising the steps of:

receiving an image at a wide-angle image capture system, which introduces a first distortion to the image so as to project a substantially hemispherical field of view onto a non-circular image sensor;

simultaneously introducing a second distortion to the image, said second distortion modifying the image projection onto the image sensor to increase total image resolution with a greater increase in image resolution for at least one selected region of interest, and projecting a greater proportion of said image corresponding to the said selected region of interest onto a greater portion of area on said sensor;

conveying the image to the image sensor, which outputs a signal;

conveying the signal to image processing circuitry which transforms both the first and second distortions into a human recognizable image output.

13. The method of claim 12, wherein the wide-angle image capture system is an optical system including a special form of fisheye lens.

14. The method of claim 12, wherein the second distortion is a radial distortion to magnify one or more regions of interest.

15. The method of claim 14, wherein the one or more regions of interest comprise a peripheral view.

16. The method of claim 12, wherein the second distortion is an asymmetric distortion to project a non-circular image.

17. The method of claim 12, wherein the second distortion includes both a radial distortion to magnify one of more regions of interest and an asymmetric distortion to project a non-circular image.

18. The method of claim 17, wherein the one or more regions of interest comprise a peripheral region.

19. The method of claim 12, wherein the first distortion warps the substantially hemisphere view into a non-circular projection onto the non-circular image sensor.

20. The method of claim 12, wherein the second distortion warps the view into a non-circular projection corresponding to the shape of the sensor to better fit upon the non-circular image sensor.