Method and system for optical tracking of a pointing object

• US 7,534,988 B2
• Filed: 11/08/2005
• Issued: 05/19/2009
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Lv, Liang, He, Deyong, Xu, Jun, Kong, Yuan, Ranta, Craig S., Xie, Jianping, Zhao, Tianpeng, Ming, Hai, Gui, Huaqiao
• Primary Examiner(s): YAM, STEPHEN K
• Application Number:
  US11/268,937
• Publication Number:
  US 20070103440A1
• Time in Patent Office: 1,288 Days
• Field of Search: 250/203.1, 250/203.2, 250/206.2, 250/221, 345/157, 345/158, 345/179, 356/3.14, 356/308, 178/18.09, 178/18.11
• US Class Current: 250/221
• 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 first pixel values from a first sensor, the pixel values corresponding to a first movement of a pointing object within a first substantially planar region that includes at least part of the first sensor and at least a first part of the pointing object;

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

determining first apparent size information with respect to at least the first part of the pointing object based on the first pixel values;

determining second apparent size information with respect to at least the second part of the pointing object based on the second pixel values;

determining first coordinates based on the first apparent size information relative to reference size information;

determining second coordinates based on the second apparent size information relative to the reference size information;

providing the first coordinates for translation into an action on a display;

determining a relationship between the first coordinates and the second coordinates; and

performing the action on the display based on the determined relationship.

2. The method of claim 1, wherein:

the determined relationship includes a tilt of the pointing object in a particular direction, and

the performed action is based on the particular direction of the tilt of the pointing object as determined by the relationship.

3. The method of claim 1, wherein:

the determined relationship includes a tilt of the pointing object in a particular direction,

the performed action is based on the particular direction of the tilt of the pointing object as determined by the relationship, and

the method further comprises;

determining an extent of the tilt of the pointing object; and

providing information based on the determined extent of the tilt to supplement the action.

4. The method of claim 1 wherein:

receiving first pixel values from a first sensor comprises;

providing light from at least one light source into the first substantially planar region; and

detecting reflected light that is reflected from the pointing object at the first sensor; and

receiving second pixel values from a second sensor comprises;

providing light from the at least one light source into the second substantially planar region; and

detecting reflected light that is reflected from the pointing object at the second sensor.

5. The method of claim 1 wherein receiving first pixel values from a first sensor comprises:

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

6. The method of claim 1 wherein receiving first pixel values from a first sensor and receiving second pixel values from a second sensor comprise:

filtering reflected light from the pointing object to remove a portion of the reflected light that does not correspond to light from at least one light source that is projected into a corresponding one of the first substantially planar region and the second substantially planar region.

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

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

8. A system comprising:

optical components including at least two sensors comprising a first sensor and a second sensor that are operable to detect a movement of a pointing object within at least one 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, the optical components being arranged such that a portion of the at least one substantially planar region is located in a free space and the movement of the pointing object within the portion of the at least one substantially planar region that is located in the free space is detected without reference to, and independent of, a physical surface, wherein there is no physical surface directly under the portion of the at least one substantially planar region; and

tracking logic operable to determine coordinates of the pointing object within the at least one substantially planar region, based on apparent size information determined for a first part of the pointing object based on pixel values received from the first sensor and apparent size information determined for the second part of the pointing object based on pixel values received from a second sensor, and further operable to provide the coordinates for translation into an action on a display.

9. The system of claim 8 wherein the optical components comprise:

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

10. The system of claim 8 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.

11. The system of claim 8 wherein a first sensor and a second sensor of the at least two sensors are angled with respect to one another.

12. The system of claim 8 wherein a first sensor of the at least two sensors includes a complementary metal-oxide-semiconductor (CMOS) image sensor.

13. The system of claim 8 wherein the tracking logic is operable to restrict detection of light reflected from the pointing object to the at least one substantially planar region by selected use of rows of pixels in the at least two sensors.

14. 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, the first image sensor being arranged such that at least a portion of the substantially planar region is located in a free space adjacent to the device and the movement of the pointing object is detected within the portion of the at least one substantially planar region that is located in the free space without reference to, and independent of, a physical surface, wherein there is no physical surface directly under the portion of the at least one substantially planar region;

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 apparent size information determined for a first part of the pointing object based on the first pixel values and apparent size information determined for the second part of the pointing object based on the second pixel values, and further operable to provide the coordinates for translation into an action on a display.

15. The device of claim 14 wherein the tracking logic is operable to perform the translation of the coordinates into the action on the display.

16. The device of claim 14 wherein the device includes a keyboard and the free space is located vertically from a top surface of the keyboard.