SINGLE-SENSOR SYSTEM FOR EXTRACTING DEPTH INFORMATION FROM IMAGE BLUR

• US 20170013245A1
• Filed: 09/23/2016
• Published: 01/12/2017
• Est. Priority Date: 01/02/2013
• Status: Active Application

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Gharib, Morteza, Jeon, David
• Granted Patent: US 10,291,894 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G06T 2207/10012 Stereo images
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 7/571 from focus
• CPC Class Codes: H04N 13/106 Processing image signals for multi-view video sequence encoding H04N19/597
• CPC Class Codes: H04N 13/211 using temporal multiplexing
• CPC Class Codes: H04N 13/236 using varifocal lenses or mirrors
• CPC Class Codes: H04N 13/246 Calibration of cameras
• CPC Class Codes: H04N 13/271 wherein the generated image signals comprise depth maps or disparity maps

Abstract

Hardware and software methodology are described for three-dimensional imaging in connection with a single sensor. A plurality of images is captured at different degrees of focus without focus change of an objective lens between such images. Depth information is extracted by comparing image blur between the images captured on the single sensor.

Claims

1. A three-dimensional imaging system comprising:

a single image sensor,

optics adapted to allow the single sensor to capture images from substantially the same viewpoint that are focused to blur in different degrees without a change of objective lens focus, and

a computer processor connected with the sensor, wherein the processor is adapted to match elements from the images and determine depth position for elements of the images by comparing differences in blurring for the elements.

2. The system of claim 1, wherein the optics comprise a moving element selected from a reflective element and a refractive element.

3. The system of claim 1, wherein the optics comprise a beam splitter.

4. The system of claim 3, wherein the optics further comprises an optical delay.

5. The system of claim 4, wherein the delay is based on an optical switchback.

6. The system of claim 4, wherein the delay is based on material refractive index.

7. The system of claim 1, wherein the optics comprise an array of micro-lenses.

8. The system of claim 7, wherein portions of the sensor are uncovered by the array.

9. The system of claim 7, wherein the array includes micro-lenses of at least two focal lengths.

10. The system of claim 1, further comprising a single objective lens assembly.

16. The method of claim 11, employing a system as described in claim 1.

11. A method of three-dimensional imaging comprising:

capturing, with a single sensor, a plurality of images of an object with a camera from substantially the same viewpoint at different focuses without moving a camera objective lens; and

using a computer processor, matching elements from the images and determining depth position for the elements of the images by comparing differences in size for the elements.

12. The method of claim 11, wherein the images are captured in a time-separated fashion on overlapping portions of the sensor.

13. The method of claim 12, further comprising moving a refractive or reflective element to produce the time-separated fashion.

14. The method of claim 11, wherein the images are captured simultaneously on different portions of the sensor without overlap.

15. The method of claim 14, wherein the different focuses are captured at different-distance image planes.