Optical tracker

• US 20070103440A1
• Filed: 11/08/2005
• Published: 05/10/2007
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Xu, Jun, Kong, Yuan, Xie, Jianping, Ranta, Craig, Zhao, Tianpeng, Lv, Liang, Ming, Hai, He, Deyong, Gui, Huaqiao
• Granted Patent: US 7,534,988 B2
• Time in Patent Office: Days
• US Class Current: 345/166
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

Optical tracking systems, method, and devices are described in which optical components detect light within a substantially planar region adjacent to a user device. Tracking logic may receive signals output by the optical components and determine coordinates associated with a movement of a pointing object through the substantially planar region. The tracking logic may then provide for translation of the coordinates into an action on a display, such as, for example, a movement of a cursor or other icon on the display.

Claims

1. A method comprising:

receiving pixel values from at least two sensors, the pixel values corresponding to a movement of a pointing object within a substantially planar region that includes at least a part of each of the two sensors and at least a part of the pointing object;

determining coordinates associated with the movement of the pointing object, based on the pixel values; and

providing the coordinates for translation into an action on a display.

2. The method of claim 1 wherein receiving pixel values from at least two sensors comprises:

providing light from a light source into the substantially planar region; and

detecting reflected light that is reflected from the pointing object at the at least two sensors.

3. The method of claim 1 wherein receiving pixel values from at least two sensors comprises:

designating a row of pixels within a first sensor of the at least two sensors, the row of pixels being substantially limited to receiving light from within the substantially planar region.

4. The method of claim 1 wherein receiving pixel values from at least two sensors comprises:

filtering reflected light from the pointing object to remove a portion of the reflected light that does not correspond to light from a light source that is projected into the substantially planar region.

5. The method of claim 1 wherein receiving pixel values from at least two sensors comprises:

receiving secondary pixel values from a row of pixels that is disposed outside of the substantially planar region; and

performing a secondary action on the display, based on the secondary pixel values.

6. The method of claim 1 wherein determining coordinates associated with the movement of the pointing object comprises:

determining a first centroid associated with a first set of pixel values detected at a first sensor of the at least two sensors;

determining a second centroid associated with a second set of pixel values detected at a second sensor of the at least two sensors; and

determining the coordinates using a triangulation calculation based on the first and second centroids.

7. The method of claim 1 wherein determining coordinates associated with the movement of the pointing object comprises:

determining the coordinates based on apparent size information associated with the pointing object and detected at a first sensor of the at least two sensors.

8. The method of claim 1 wherein providing the coordinates for translation into an action on a display comprises:

providing a cursor control action on the display.

9. The method of claim 1 wherein providing the coordinates for translation into an action on a display comprises:

transmitting the coordinates to an external device for the translation into the action on the display.

10. The method of claim 1 comprising:

determining a motion of the pointing object into or out of the planar region, based on a presence or absence of reflected light from the pointing object as detected by the at least two sensors; and

providing a secondary action on the display, based on the motion.

11. A system comprising:

optical components including at least two sensors that are operable to detect a movement of a pointing object within a substantially planar region that includes at least a part of each of the at least two sensors and at least a part of the pointing object, and further operable to output pixel values corresponding to the movement; and

tracking logic operable to determine coordinates of the pointing object within the planar region, based on the pixel values, and further operable to provide the coordinates for translation into an action on a display.

12. The system of claim 11 wherein the optical components comprise:

at least one source of non-structured light illuminating the substantially planar region, for detection of light reflected therefrom by the pointing object.

13. The system of claim 11 wherein the optical components comprise:

a lens system aligned with the at least two sensors and operable to focus reflected light from the pointing object on associated ones of the at least two sensors.

14. The system of claim 11 wherein a first sensor and a second sensor of the at least two sensors are angled with respect to one another.

15. The system of claim 11 wherein a first sensor of the at least two sensors includes a complementary metal-oxide-semiconductor (CMOS) image sensor.

16. The system of claim 11 wherein the tracking logic is operable to restrict detection of light reflected from the pointing object to the substantially planar region by selected use of rows of pixels in the at least two sensors.

17. The system of claim 11 wherein the tracking logic is operable to determine a first centroid of the pointing object at a first sensor and a second centroid of the pointing object at a second sensor, and further operable to perform a triangulation calculation to determine the coordinates, based on the first centroid, the second centriod, and the part of the pointing object within the substantially planar region.

18. A device comprising:

a first image sensor disposed on an axis and operable to output first pixel values corresponding to a movement of a pointing object within a substantially planar region that includes the axis and the pointing object;

a second image sensor disposed on the axis and operable to output second pixel values corresponding to the movement; and

tracking logic operable to determine coordinates of the pointing object within the substantially planar region, based on the first pixel values and the second pixel values, and further operable to provide the coordinates for translation into an action on a display.

19. The device of claim 18 wherein the tracking logic is operable to perform the translation of the coordinates into the action on the display.

20. The device of claim 18 wherein the device includes one or more of a keyboard, a mouse, a wireless communications device, a personal digital assistant, a display, a desktop computer, a tablet personal computer, a cell phone, a gaming device, and/or a laptop computer.