Backlight for touchless gesture detection

Patent metadata

Field	Value
Publication number	US-9304596-B2
Application number	US-201313949748-A
Country	US
Kind code	B2
Filing date	Jul 24, 2013
Priority date	Jul 24, 2013
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A device and method to detect a gesture performed by an object in touch-less communication with the device are described. The device includes two or more ambient light sensors arranged at respective first surface locations of the device, each of the two or more ambient light sensors sensing light intensity at the respective first surface location. The device also includes one or more processors to control one or more light sources at respective second surface locations of the device based on the light intensity sensed by the two or more ambient light sensors, calibrate the two or more ambient light sensors based on the one or more light sources, and detect the gesture based on the light intensity sensed by each of the two or more ambient light sensors.

First claim

What is claimed is:

1. A device to detect a gesture performed by an object in touch-less communication with the device, the device comprising:
two or more ambient light sensors arranged at respective first surface locations of the device, each of the two or more ambient light sensors configured to sense light intensity at the respective first surface locations;
one or more processors configured to:
control two or more light sources at respective second surface locations of the device based on the light intensity sensed by the two or more ambient light sensors,
calibrate the two or more ambient light sensors in response to an ambient light level falling below a minimum threshold level for a first duration when the two or more light sources are turned off, wherein the two or more ambient light sensors are initially calibrated to provide a first set of light intensity measurements while the two or more light sources are off;
turn on each of the two or more light sources after calibrating the two or more ambient light sensors; and
detect the gesture based on light intensity sensed by each of the two or more ambient light sensors when the two or more light sources are turned on.

2. The device according to claim 1 , wherein a number of the two or more ambient light sensors is equal to a number of the two or more light sources and each respective first surface location corresponds with one of the respective second surface locations such that the two or more ambient light sensors are proximate to the two or more light sources, respectively.

3. The device according to claim 1 , wherein, after the two or more light sensors are initially calibrated to provide the first set of light intensity measurements, the one or more processors calibrate the two or more ambient light sensors to provide additional sets of light intensity measurements by turning on each of the two or more light sources one at a time as each of the two or more ambient light sensors sense light intensity at the respective first surface locations.

4. The device according to claim 3 , wherein, after the two or more light sensors are calibrated to provide the additional sets of light intensity measurements, the one or more processors calibrate the two or more ambient light sensors to provide a final set of light intensity measurements by turning on each of the two or more light sources as each of the two or more light sensors sense light intensity at the respective first surface locations, and in turn, the one or more processors establish a phase synchronization between the two or more light sources and the two or more ambient light sensors based on the light intensity measurement sets provided from the calibration.

5. The device according to claim 4 , wherein the one or more processors cause one of the light sources to be turned off with each of the other light sources being turned on when light intensity sensed by one of the ambient light sensors exceeds a maximum threshold level for a second duration that is longer than the first duration.

6. The device according to claim 4 , wherein the one or more processors adjust the two or more ambient light sensors during the calibration to sense a specific light intensity regardless of a level of ambient light from sources other than the two or more light sources.

7. The device according to claim 6 , wherein the final set of light intensity measurements comprises a specific light intensity for each of the two or more ambient light sensors that is a same light intensity as one another.

8. The device according to claim 6 , wherein at least one of the additional sets of light intensity measurements comprises a specific light intensity for one of the two or more ambient light sensors that is a different light intensity than the specific light intensity for each of the other two or more ambient light sensors, wherein the specific light intensity for each of the other two or more ambient light sensors is identical.

9. A method of detecting a gesture made by an object in touch-less communication with a device, the method comprising:
sensing, using two or more ambient light sensors arranged at respective first surface locations of the device, light intensity at the respective first surface locations;
controlling, using one or more processors, two or more light sources at respective second surface locations based on the light intensity sensed by the two or more ambient light sensors;
turning off the two or more light sources when an ambient light level is above a minimum threshold level;
calibrating, using the one or more processors, the two or more ambient light sensors in response to the ambient light level falling below the minimum threshold level for a first duration, wherein the two or more ambient light sensors are initially calibrated to provide a first set of light intensity measurements while the two or more light sources are off;
turning on each of the two or more light sources after calibrating the two or more ambient light sensors; and
detecting, using the one or more processors, the gesture based on light intensity sensed by each of the two or more ambient light sensors when the two or more light sources are turned on.

10. The method according to claim 9 , further comprising the one or more processors:
responsive to initially calibrating the two or more ambient light sensors to provide the first set of light intensity measurements, calibrating the two or more ambient light sensors to provide additional sets of light intensity measurements by turning on each of the two or more light sources one at a time as each of the two or more ambient light sensors sense light intensity at the respective first surface locations.

11. The method according to claim 10 , wherein, responsive to calibrating the two or more light sensors to provide the additional sets of light intensity measurements, the method further comprises calibrating the two or more ambient light sensors to provide a final set of light intensity measurements by turning on each of the two or more light sources as each of the two or more light sensors sense light intensity at the respective first surface locations, and in turn, establishing a phase synchronization between the two or more light sources and the two or more ambient light sensors based on the light intensity measurement sets provided from the calibration.

12. The method according to claim 11 , wherein the one or more processors cause one of the light sources to be turned off with each of the other light sources being turned on when light intensity sensed by one of the ambient light sensors exceeds a maximum threshold level for a second duration that is longer than the first duration.

13. The method according to claim 11 , further comprising the one or more processors adjusting the two or more ambient light sensors during the calibration to sense a specific light intensity regardless of a level of ambient light from sources other than the two or more light sources.

14. The method according to claim 13 , wherein the final set of light intensity measurements comprises a specific light intensity for each of the two or more ambient light sensors that is a same light intensity as one another.

15. The method according to claim 13 , wherein at least one of the additional sets of light intensity measurements comprises a specific light intensity for one of the two or more ambient light sensors that is a different light intensity than the specific light intensity for each of the two or more ambient light sensors, wherein the specific light intensity for each of the other two or more ambient light sensors is identic

Assignees

• Blackberry Ltd

Inventors

• Mankowski Peter
• Rang Weimin
• Wu Xiaowei

Classifications

• G06F3/0325

  using a plurality of light emitters or reflectors or a plurality of detectors forming a reference frame from which to derive the orientation of the object, e.g. by triangulation or on the basis of reference deformation in the picked up image · CPC title

• G01J1/4228

  arrangements with two or more detectors, e.g. for sensitivity compensation · CPC title

• G06F3/017 Primary

  Gesture based interaction, e.g. based on a set of recognized hand gestures (interaction based on gestures traced on a digitiser G06F3/04883) · CPC title