Dual mode depth imaging

• US 20090128833A1
• Filed: 11/15/2007
• Published: 05/21/2009
• Est. Priority Date: 11/15/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft International Holdings BV (Microsoft Corporation)
• Inventors: Yahav, Giora
• Granted Patent: US 7,852,461 B2
• Time in Patent Office: Days
• US Class Current: 356/623
• CPC Class Codes: G01S 17/48 Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: H04N 13/207 using a single 2D image sensor
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects

Abstract

Dual mode depth imaging system and method is provided, the system comprising a first and second image sensors and a processor able to switch between a first mode of depth imaging and a second mode of depth imaging according to at least one predefined threshold. The method comprising providing depth sensing by Time of Flight if the distance of the sensed object from the camera is not below a first threshold and/or if a depth resolution above a second threshold is not required, and providing depth sensing by triangulation, if the distance of the sensed object from the camera is below the first threshold and/or if a depth resolution above the second threshold is required.

Claims

1. A system for dual mode depth imaging, the system comprising:

a first and second image sensors; and

a processor able to switch between a first mode of depth imaging and a second mode of depth imaging according to at least one predefined threshold.

2. A system according to claim 1, wherein said processor is to activate said first and second image sensors in a first mode of depth imaging when the distance of a sensed object from said system is below a first threshold, and to activate said first and second image sensors in a second mode of depth imaging when the distance of said sensed object from said system is above said first threshold.

3. A system according to claim 1, wherein said first image sensor is to provide depth imaging according to Time-of-Flight of pulsed radiation reflected from an imaged object.

4. A system according to claim 1, wherein said second image sensor is to sense color of an imaged object.

5. A system according to claim 1, wherein said first mode of depth imaging includes calculation of distances by triangulation based on geometrical parameters derived from at least one of the first and second image sensors.

6. A system according to claim 1, wherein said second mode of depth imaging includes calculation of distances according to Time-of-Flight of pulsed radiation reflected from an imaged object.

7. A system according to claim 1, wherein said processor is further to activate said first and second image sensors in a first mode of depth imaging when depth resolution above a second threshold is required.

8. A system according to claim 1, wherein said first image sensor is black and white sensor.

9. A system according to claim 2, wherein the value of said first threshold is approximately several tens of centimeters.

10. A system according to claim 1, wherein said processor is to switch between said first mode of depth imaging and said second mode of depth imaging when the distance of the sensed object from said system exceeds said threshold, and to switch between said second mode of depth imaging and said first mode of depth imaging when the distance of the sensed object from said system decreases below said threshold.

11. A system according to claim 1, wherein the dynamic range of said first mode of depth imaging is substantially from a few centimeters to several tens of centimeters.

12. A system according to claim 1, wherein the dynamic range of said second mode of depth imaging is substantially from several tens of centimeters to a few meters.

13. A system according to claim 6, further including a radiation source.

14. A system according to claim 5, wherein said processor is further to match the images received from the first and second image sensors.

15. A method for dual mode depth imaging, the method comprising:

checking distance of a sensed object from a camera to conclude whether said distance is below a first threshold;

providing depth sensing by Time of Flight, if the distance of the sensed object from the camera is not below said first threshold; and

providing depth sensing by triangulation, if the distance of the sensed object from the camera is below said first threshold.

16. A method for dual mode depth imaging, the method comprising:

checking whether a depth resolution above a second threshold is required;

providing depth sensing by Time of Flight, if a depth resolution above the second threshold is not required; and

providing depth sensing by triangulation, if a depth resolution above the second threshold is required.