Device and method for calculating a location on a display

• US 20050104849A1
• Filed: 12/20/2002
• Published: 05/19/2005
• Est. Priority Date: 12/21/2001
• Status: Active Grant

• Current Assignee: British Telecommunications PLC (BT Group PLC)
• Original Assignee: British Telecommunications PLC (BT Group PLC)
• Inventors: Hoile, Cefn
• Granted Patent: US 7,161,596 B2
• Time in Patent Office: Days
• US Class Current: 345/157
• CPC Class Codes: G06F 3/0325 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

Abstract

Display location calculation means and methods for calculating a display location are disclosed. It has become common for users to indicate a point on a display in order to communicate with a machine. It is therefore necessary to be able to calculate the location on the display that is being indicated by the user. A display generator (123) is arranged in operation to generate a display in response to display data generated by a machine (111). A camera operable to generate image data representing at least part of the scene within the field of view of the camera (which part, includes at least a portion of the display) is carried in a pointer device (103). Computation means (111, 113, 115) are arranged in operation to receive the image data and the display data and to calculate from these data sets the position and/or orientation of the pointer device (103) relative to the display. A display location can then be calculated from the calculated position and/or orientation.

Claims

1. Display location calculation means comprising:

a display generator arranged in operation to generate a display in response to display data generated by a machine;

a pointer device carrying a camera operable to generate image data representing at least part of the scene within the field of view of the camera, which part, includes an image of at least a portion of the display;

computation means arranged in operation to;

receive said image data;

receive said display data;

calculate, from said image data and said display data, the position and/or orientation of said pointer device relative to said display;

calculate a display location from said calculated position and/or orientation.

2. Display location calculation means according to claim 1 wherein said pointer device is elongate in shape and wherein said display location is the point where the longitudinal axis of said pointer device intersects with said display.

3. Display location calculation means according to claim 1 wherein a cursor is included in said display at said display location.

4. Display location calculation means according to claim 3 wherein the position of said cursor varies in accordance with said calculated position and/or orientation.

5. An interface arrangement for providing an interface between a user and a machine comprising:

display location calculation means according to claim 2;

wherein said computation means is further arranged in operation to control said machine in accordance with the position of the cursor.

6. An interface arrangement according to claim 5 wherein said machine comprises a computer having a processor and wherein said computation means comprises said processor.

7. An interface arrangement according to claim 5 wherein said pointer device further carries a computer having a processor and wherein said computation means comprises said processor.

8. An interface arrangement according to claim 5 wherein said machine comprises a first computer having a first processor and wherein said pointer device further carries a second computer having a second processor and wherein said computation means comprises said first processor and said second processor.

9. An interface arrangement according to any one of claim 5 wherein said pointer device further comprises at least one activation means for use in controlling said machine.

10. An interface arrangement according to any one of claim 5 wherein said display generator comprises a projector.

11. An interface arrangement according to claim 5 wherein said camera is a digital video camera.

12. An interface arrangement according to claim 5 wherein said camera is a fixed focus camera.

13. An interface arrangement according to claim 12 further comprising an indicator arranged in operation to indicate that the image captured by said camera is focussed.

14. An interface arrangement according to claim 5 wherein said camera has a fixed spatial relationship with said pointer device.

15. A method of calculating a display location said method comprising the steps of:

i. generating a display in accordance with display data generated by said machine;

ii. capturing image data representing at least part of the scene within the field of view of a camera carried by a pointer device wherein at least a portion of said display is included in said field of view;

iii. calculating from said image data and said display data the position and/or orientation of said pointer device relative to said display;

iv. calculating an display location from said calculated position and/or orientation.

16. A method according to claim 15 comprising the additional step of generating a cursor in said display at said display location.

17. A method according to claim 16 wherein the position of said cursor varies in accordance with said calculated position and/or orientation.

18. A method according to claim 17 wherein said pointer device is elongate in shape and wherein said display location is the point where the longitudinal axis of said pointer device intersects with said display.

19. A method according to claim 15 comprising the additional step of storing data representing the history of the position and/or orientation of said pointer device relative to said display and wherein said calculation step (iii) further takes into account said data.

21. A digital data carrier carrying a program of instructions executable by processing apparatus to perform the method steps as set out in claim 15.

20. Display location calculation means including:

a storage medium having recorded therein processor readable code processable to provide an interface between a user and a machine said code comprising;

display data acquisition code processable to obtain display data representing a display

image data acquisition code processable to obtain from a pointer device carrying a camera, image data representing at least part of the scene within the field of view of said camera;

position/orientation calculation code processable to calculate from said display data and said image data the position and/or the orientation of said pointer device relative to said display

display location calculation code processable to calculate from said calculated position and/or orientation a display location.