Multi-camera system using folded optics

• US 9,398,264 B2
• Filed: 03/15/2013
• Issued: 07/19/2016
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Georgiev, Todor G., Osborne, Thomas Wesley, Goma, Sergiu Radu
• Primary Examiner(s): Jerabek, Kelly L
• Application Number:
  US13/837,098
• Publication Number:
  US 20140111650A1
• Time in Patent Office: 1,222 Days
• Field of Search: 348/36, 348 38- 39, 348/143, 348/218.1, 348/239, 348/262
• US Class Current: 1/1
• CPC Class Codes: G02B 13/0065 having a beam-folding prism or mirror
• CPC Class Codes: G06T 3/4038 Image mosaicing, e.g. composing plane images from plane sub-images
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/698 for achieving an enlarged field of view, e.g. panoramic image capture
• CPC Class Codes: H04N 23/90 Arrangement of cameras or camera modules, e.g. multiple cameras in TV studios or sports stadiums
• CPC Class Codes: H04N 25/41 Extracting pixel data from a plurality of image sensors simultaneously picking up an image, e.g. for increasing the field of view by combining the outputs of a plurality of sensors
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

Described herein are methods and devices that employ a plurality of image sensors to capture a target image of a scene. As described, positioning at least one reflective or refractive surface near the plurality of image sensors enables the sensors to capture together an image of wider field of view and longer focal length than any sensor could capture individually by using the reflective or refractive surface to guide a portion of the image scene to each sensor. The different portions of the scene captured by the sensors may overlap, and may be aligned and cropped to generate the target image.

Claims

1. An image capture system for capturing a target image of a scene, the system comprising:

a plurality of image sensors, each of the plurality of image sensors having one of a plurality of fields of view, each of the plurality of fields of view comprising a substantially different portion of the scene;

a plurality of lens assemblies, each lens assembly corresponding to one of the plurality of image sensors;

at least one primary surface positioned so as to reflect light comprising at least a portion of the scene through the plurality of lens assemblies;

a plurality of reflective secondary surfaces, each of the plurality of lens assemblies positioned between the at least one primary surface and a corresponding one of the plurality of secondary surfaces such that each of the plurality of secondary surfaces receives at least a portion of the light from one of the plurality of lens assemblies and reflects the received light toward a corresponding one of the plurality of image sensors, and wherein each of the plurality of image sensors captures one of a plurality of partial images, each of the plurality of partial images corresponding to one of the plurality of fields of view; and

a processing module configured to assemble the plurality of partial images into the target image.

2. The image capture system of claim 1, further comprising a substantially flat substrate, wherein the plurality of image sensors are positioned on the substantially flat substrate.

3. The image capture system of claim 2, wherein the plurality of sensors are positioned laterally adjacent to one another on the substrate.

4. The image capture system of claim 2, wherein the plurality of sensors are arranged in two rows on the substrate, and wherein the at least one primary surface is positioned between the two rows.

5. The image capture system of claim 2, wherein the plurality of sensors are arranged in a circular manner around the primary surface on the substrate.

6. The image capture system of claim 1, wherein the at least one primary surface comprises a prism having at least one surface configured to reflect the light.

7. The image capture system of claim 6, wherein the prism comprises a plurality of facets, and wherein each of the plurality of facets reflects a portion of the light comprising one of the plurality of fields of view toward one of the plurality of lens assemblies.

8. The image capture system of claim 1, wherein the at least one primary surface comprises a plurality of primary reflective surfaces, and wherein each of the plurality of primary reflective surfaces reflects a portion of the light comprising one of the plurality of fields of view toward one of the plurality of lens assemblies.

9. A method of capturing a target image of a scene, the method comprising:

providing plurality of image sensors, each of the plurality of image sensors having one of a plurality of fields of view, each of the plurality of fields of view comprising a substantially different portion of the scene;

providing a plurality of lens assemblies, each lens assembly corresponding to one of the plurality of image sensors;

reflecting light comprising at least a portion of the scene toward each of the plurality of lens assemblies using at least one primary surface;

reflecting the light from each of the plurality of lens assemblies toward a corresponding one of the plurality of image sensors using a plurality of reflective secondary surfaces, the plurality of secondary surfaces each positioned between a corresponding one of the plurality of lens assemblies and the corresponding one of the plurality of image sensors;

capturing a plurality of partial images, wherein each of the plurality of partial images is captured by one of the plurality of image sensors and corresponds to one of the plurality of fields of view; and

assembling the plurality of partial images into the target image.

10. The method of claim 9, wherein assembling the plurality of partial images comprises:

combining the plurality of partial images into a combination image; and

cropping the combination image according to a desired aspect ratio to produce the target image.

11. The method of claim 9, wherein assembling the plurality of partial images comprises:

determining at least one area of overlap in the plurality of partial images; and

aligning the plurality of partial images based at least in part on the at least one area of overlap, thereby generating an aligned image comprising the scene.

12. The method of claim 11, further comprising cropping the aligned image according to a desired aspect ratio to produce the target image.

13. The method of claim 9, further comprising focusing the plurality of partial images using the plurality of lens assemblies.

14. The method of claim 9, wherein directing light comprising at least a portion of the scene toward each of the plurality of lens assemblies comprises reflecting the light using at least one primary reflective surface.

15. The method of claim 14, wherein reflecting the light using at least one primary reflective surface comprises reflecting a portion of the light comprising one of the plurality of fields of view toward each of the plurality of lens assemblies using a plurality of primary reflective surfaces.

16. The method of claim 9, wherein directing light comprising at least a portion of the scene toward each of the plurality of lens assemblies comprises refracting the light using at least one prism.

17. The method of claim 16, wherein refracting the light using at least one prism comprises refracting the light through a plurality of facets of the prism, wherein a portion of the light comprising each one of the plurality of fields of view is refracted through one of the plurality of facets toward one of the plurality of lens assemblies.

18. A non-transitory computer readable medium comprising instructions that when executed by a processor perform a method comprising:

capturing image data of a plurality of portions of a target image scene using a plurality of image sensors, each of the plurality of image sensors having one of a plurality of substantially different fields of view determined by reflecting light comprising at least a portion of the scene from at least one primary surface through one of a plurality of lens assemblies and then reflecting said light off of one of a plurality of reflective secondary surfaces, and wherein each of the plurality of portions of the target image corresponds to one of the plurality of fields of view;

wherein the first field of view and the second field of view are determined at least in part based on at least one surface configured to reflect or refract light comprising the scene toward the first and second image sensors; and

combining the plurality of portions of the target image into the target image.

19. An image capture system for capturing a target image of a scene, the system comprising:

a central reflective component positioned to receive light representing the scene and reflect the light toward a plurality of cameras; and

the plurality of cameras, each of the plurality of cameras comprising;

an image sensor configured to capture a portion of the light representing the scene,

a lens assembly positioned to receive the portion of the light from the central reflective component, and

an additional reflective surface positioned between the lens assembly and the image sensor such that the additional reflective surface receives the portion of the light from the lens assembly and reflects the portion of the light onto the image sensor.

20. The image capture system of claim 19, wherein, for each of the plurality of cameras, the lens assembly is positioned between the central reflective component and the additional reflective surface.

21. The image capture system of claim 19, wherein the central reflective component comprises a plurality of reflective surfaces, each of the plurality of reflective surfaces positioned to redirect a portion of the light toward a corresponding one of the plurality of cameras.