Detection surface for a computing device

• US 9,223,441 B1
• Filed: 08/07/2014
• Issued: 12/29/2015
• Est. Priority Date: 08/07/2014
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Bohn, David D.
• Primary Examiner(s): Osorio, Richardo L
• Application Number:
  US14/454,583
• Time in Patent Office: 509 Days
• US Class Current: 1/1
• CPC Class Codes: G01S 17/08 for measuring distance only indirect measurement G01S17/46; active triangulation systems G01S17/48
• CPC Class Codes: G01S 7/4808 Evaluating distance, position or velocity data
• CPC Class Codes: G01S 7/4816 of receivers alone
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A system determines a position of one or more objects relative to a detection surface. An illumination source is located at a first fixed position relative to the detection surface, and configured to illuminate an adjacent coordinate space. Two or more single-pixel optical sensors are located at fixed positions relative to the detection surface such that each point of the illuminated coordinate space is within a field of view of at least two single-pixel optical sensors. Each single-pixel optical sensor detects illumination reflected off an object within the coordinate space, and outputs information useable to assess a time-of-flight of the detected reflected illumination. A controller assesses a radial distance between each single-pixel sensor and the object based at least in part on the time-of-flight of the detected reflected illumination, and determines a position of the object in the coordinate space based at least in part on the radial distances.

Claims

1. A system for determining a position of one or more objects relative to a detection surface, comprising:

a first illumination source located at a first fixed position relative to the detection surface, the first illumination source configured to illuminate at least a portion of a coordinate space located adjacent to the detection surface;

two or more single-pixel optical sensors located at fixed positions relative to the detection surface and arranged such that each point of the coordinate space which the first illumination source is configured to illuminate, is within a field of view of at least two of the two or more single-pixel optical sensors, each of the single-pixel optical sensors is configured to detect illumination reflected off an object within the coordinate space, and further configured to output information useable to assess a time-of-flight of the detected reflected illumination; and

a controller configured to assess a radial distance between each of the single-pixel optical sensors and the object based at least in part on the time-of-flight of the detected reflected illumination, and further configured to determine a position of the object in the coordinate space based at least in part on the radial distances between the object and the two or more single-pixel optical sensors.

2. The system of claim 1, wherein the two or more single-pixel optical sensors include:

a first single-pixel optical sensor located at the first fixed position relative to the detection surface; and

one or more single-pixel optical sensors located at known positions relative to the first fixed position.

3. The system of claim 2, wherein the first single-pixel optical sensor is a master single-pixel optical sensor, and wherein the one or more single-pixel optical sensors located at known positions relative to the first fixed position are slave single-pixel optical sensors, the slave single-pixel optical sensors communicatively coupled to the master single-pixel optical sensor via a clock signal.

4. The system of claim 2, further comprising:

one or more additional illumination sources, each illumination source located at a unique location relative to the detection surface, and each illumination source configured to output illumination with at least one property unique to that illumination source, and further configured to illuminate at least a portion of the coordinate space located adjacent to the detection surface.

5. The system of claim 4, wherein each illumination source is paired to a master single-pixel optical sensor located at the unique location occupied by the paired illumination source, each master single-pixel optical sensor is configured to detect illumination output by the paired illumination source that has been reflected off a nearest object within the coordinate space, and is further configured to output information useable to assess a time-of-flight of the detected reflected illumination.

6. The system of claim 5, wherein the controller is further configured to:

assess a radial distance between each master single-pixel sensor and a nearest object in the coordinate space based at least in part on the time-of-flight of the detected reflected illumination, and further configured to determine a position of one or more objects in the coordinate space based at least in part on the radial distances between the one or more objects and the master single-pixel optical sensors.

7. The system of claim 5, wherein each master single-pixel optical sensors is communicatively coupled to one or more slave single-pixel optical sensors via a clock signal, the one or more slave single-pixel optical sensors located at known positions relative to the coupled master single-pixel optical sensor.

8. The system of claim 4, wherein each illumination source is configured to output illumination with a unique wavelength.

9. The system of claim 4, wherein each illumination source is configured to output illumination pulsations, and wherein a timing of the illumination pulsations for each illumination source is offset from the illumination pulsations output by each other illumination source.

10. The system of claim 2, wherein the coordinate space is a three-dimensional space located adjacent to the detection surface, and where at least two single-pixel optical sensors are located at known positions relative to the first fixed position.

11. The system of claim 10, wherein the determined position of the object in the coordinate space includes a distance of the object from the detection surface.

12. The system of claim 11, wherein the controller is further configured to:

indicate an object in contact with the detection surface based at least in part on the distance of the object from the detection surface being less than a threshold.

13. The system of claim 2, wherein the position of the object in the coordinate space is adjusted based at least in part on an indication that a diameter of the object is greater than a threshold.

14. The system of claim 1, wherein each single-pixel optical sensor is configured to view the coordinate space through an aperture configured to limit the field of view of the single-pixel optical sensor.

15. The system of claim 1, wherein the coordinate space is a two-dimensional space located parallel to the detection surface.

16. The system of claim 1, wherein the detection surface further comprises one or more contact sensors configured to output information usable to determine that one or more objects are in contact with the detection surface.

17. The system of claim 1, wherein the detection surface further comprises a display surface.

18. The system of claim 1, wherein the information useable to assess a time-of-flight of the detected reflected illumination includes a signal indicating a relative amount of illumination detected by the single-pixel optical sensor during a gating period, and wherein the controller determines the time-of-flight of the detected reflected illumination based at least in part on the signal.

19. A method for detecting the location of an object relative to a detection surface, comprising:

illuminating a coordinate space located adjacent to the detection surface with an illumination source located at a first fixed position relative to the detection surface;

communicatively coupling a master single-pixel optical sensor located at the first fixed position with one or more slave single-pixel optical sensors located at known distances from the first fixed position, the one or more slave single-pixel optical sensors arranged such that each point of the coordinate space illuminated by the illumination source is within a field of view of at least two single-pixel optical sensors;

at the master single-pixel optical sensor, detecting illumination reflected off an object located in the coordinate space;

determining a radial distance between an object located in the coordinate space and the master single-pixel optical sensor based at least in part on a time-of-flight of the reflected illumination detected by the master single-pixel optical sensor;

at the one or more slave single-pixel optical sensors, receiving illumination reflected off the object located in the coordinate space;

determining a radial distance between the object located in the coordinate space and the one or more slave single-pixel optical sensors based at least in part on a time-of-flight of the reflected illumination detected by one or more slave single-pixel optical sensors and further based at least in part on the known distances from the one or more slave single-pixel optical sensors to the first fixed position; and

determining a location of the object within the coordinate space based at least in part on the determined radial distances.

20. A system for detecting the location of an object relative to a detection surface, comprising:

a first illumination source located at a first fixed position relative to the detection surface, the first illumination source configured to illuminate at least a portion of a coordinate space located adjacent to the detection surface;

a first single-pixel optical sensor paired to the first illumination source at the first fixed position and configured to receive reflected illumination output by the first illumination source;

a second illumination source located at a second fixed position relative to the detection surface, the second illumination source configured to illuminate at least a portion of the coordinate space located adjacent to the detection surface, and further configured to output illumination with at least one illumination property different from illumination output by the first illumination source;

a second single-pixel optical sensor paired to the second illumination source at the second fixed position and configured to receive reflected illumination originating at the second illumination source; and

a controller operable to;

determine a first radial distance indicating a distance from an object located in the coordinate space to the first single-pixel optical sensor based at least in part on a time-of-flight of illumination output by the first illumination source and received at the first single-pixel optical sensor;

determine a second radial distance indicating a distance from the object located in the coordinate space to the second single-pixel optical sensor based at least in part on a time-of-flight of illumination output by the second illumination source and received at the second single-pixel optical sensor; and

determine a location of the object located in the coordinate space based at least in part on the first and second radial distances.