Coordinate input device working with at least display screen and desk-top surface as the pointing areas thereof

• US 20030085871A1
• Filed: 10/07/2002
• Published: 05/08/2003
• Est. Priority Date: 10/09/2001
• Status: Active Grant

• Current Assignee: EIT Co. Ltd. (Minato Holdings Inc.), Xiroku, Inc.
• Original Assignee: E-Business Information Technology
• Inventors: Ogawa, Yasuji
• Granted Patent: US 7,202,860 B2
• Time in Patent Office: Days
• US Class Current: 345/158
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A coordinate input device includes a pair of cameras positioned in an upper left position and an upper right position of a display screen of a monitor lying close to a plane extending from the display screen of the monitor and views both a side face of an object in contact with a position on the display screen and a predetermined desk-top coordinate detection area to capture the image of the object within the field of view. The coordinate input device also includes a control circuit which calculates the coordinate value of a pointing tool, pointing to a position within a coordinate detection field, based on video signals output from the pair of cameras, and transfers the coordinate value to a program of a computer.

Claims

1. A coordinate input device comprising:

a pair of cameras positioned in an upper left position and an upper right position of a display screen of a monitor lying close to a plane extending from the display screen of the monitor and views both a side face of an object in contact with a position on the display screen and a predetermined desk-top coordinate detection area to capture the image of the object within a field of view; and

a control circuit which calculates the coordinate value of a pointing tool, pointing to a position within a coordinate detection field, based on video signals output from the pair of cameras, and transfers the coordinate value to a program of a computer.

2. The coordinate input device according to claim 1, further comprising a reflective outline frame formed of a member having a high reflectance and a member having a low reflectance running side by side along three sides of the display screen except a top side of the display screen so that a border line between the two members comes within the fields of view of the two cameras.

3. The coordinate input device according to claim 1, wherein the pointing tool includes a retroreflection member at its tip.

4. The coordinate input device according to claim 1, further comprising a display screen which is integrated with the pair of cameras in a unitary structure.

5. The coordinate input device according to claim 1, wherein the coordinate detection field includes the display screen of the monitor and the predetermined desk-top coordinate detection area.

6. The coordinate input device according to claim 2, further comprising a touch detector in the control circuit for detecting a touch input on the display screen when the pointing tool crosses the border line.

7. The coordinate input device according to claim 3, wherein each of the pair of cameras includes infrared emitting diodes in the vicinity of an imaging lens for illuminating the coordinate detection field.

8. The coordinate input device according to claim 7, wherein the cameras receive light reflected from the retroreflection member in response to light emitted from the infrared emitting diodes.

9. The coordinate input device according to claim 1, wherein the pointing tool is selected from the group consisting of a user'"'"'s finger and a pen.

10. The coordinate input device according to claim 1, wherein the control unit is separate from the computer.

11. A coordinate input device comprising:

means for capturing an image positioned in an upper left position and an upper right position of a display screen of a monitor lying close to a plane extending from the display screen of the monitor and views both a side face of an object in contact with a position on the display screen and a predetermined desk-top coordinate detection area to capture the image of the object within a field of view, and

means for calculating the coordinate value of a pointing tool pointing to a position within a coordinate detection field, based on video signals output from the means for capturing an image, and transferring the coordinate value to a program of a computer.

12. The coordinate input device according to claim 11, further comprising means for reflecting formed of a member having a high reflectance and a member having a low reflectance running side by side along three sides of the display screen except a top side of the display screen so that a border line between the two members come within the field of view of the means for capturing an image.

13. The coordinate input device according to claim 11, wherein the pointing tool includes a retroreflection member at its tip.

14. The coordinate input device according to claim 11, wherein the coordinate detection field includes the display screen of the monitor and the predetermined desk-top coordinate detection area.

15. The coordinate input device according to claim 12, further comprising a touch detector means in the control circuit for detecting a touch input on the display screen when the pointing tool crosses the border line.

16. The coordinate input device according to claim 13, wherein the means for capturing an image includes means for illuminating in the vicinity of an imaging lens for illuminating the coordinate detection field.

17. The coordinate input device according to claim 16, wherein the means for capturing an image receives light reflected from the retroreflection member in response to light emitted from the means for illuminating.

18. The coordinate input device according to claim 11, wherein the pointing tool is selected from the group consisting of a user'"'"'s finger and a pen.

19. A method for inputting image information comprising:

capturing image data;

determining a pixel that provides a signal at the highest signal level from the captured image data; and

calculating touch coordinates using a pixel-coordinate table from a position of the pixel that provides a signal at the highest level.

20. The method according to claim 19, further comprising detecting a touch input representing image data.