Coordinate input apparatus and the recording medium thereof

• US 6,563,491 B1
• Filed: 09/11/2000
• Issued: 05/13/2003
• Est. Priority Date: 09/10/1999
• Status: Expired due to Term

• Current Assignee: Smart Technologies ULC (Hon Hai Precision Industry Co., Ltd.), Package Supply & Equipment Co., Inc.
• Original Assignee: Ricoh Company Limited
• Inventors: Omura, Katsuyuki
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): ZAMANI, ALI A
• Application Number:
  US09/659,822
• Time in Patent Office: 974 Days
• Field of Search: 345/173, 345/178, 345/174, 345/175, 345/176, 345/177, 178/18.1, 178/18.01, 178/19.01
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

An apparatus that includes angle detection sections periodically detecting a point on a panel as angles. An angle storing section stores the angles detected during an immediately earlier Ucycle among angles periodically detected, and an angle choosing section chooses angles which are most adjacent to the angles stored among angles detected during the immediately earlier cycle when a number of angles detected during a present cycle is greater than a number of angles detected during the immediately earlier cycle. A coordinate arithmetic section detects during the immediately earlier cycle coordinates based on the angles chosen. In this apparatus, when the number of angles detected during the present cycle is one greater than the number of angles detected during the immediately earlier cycle for each angle detecting section, the coordinates inputted by an other pointing device can be detected through angles which have not been chosen.

Claims

1. A coordinate input apparatus comprising:

a coordinate input face where coordinates are inputted by a pointing unit,

a detection unit configured to periodically detect at least two angles formed by straight lines connecting a point corresponding to said pointing unit on said coordinate input face and reference points on said coordinate input face and a reference line on the coordinate input face,

an angle storing unit configured to store angles detected by the detection unit during an immediately earlier cycle among angles periodically detected,

an angle choosing unit configured to compare the angles detected during the immediately earlier cycle with angles detected during a present cycle, and to choose those angles determined during the present cycle that have a value most adjacent to a value of the angles detected during the immediately earlier cycle if a number of the angles detected during the present cycle is greater than a number of the angles detected during the immediately earlier cycle, and

a coordinate detection unit configured to detect coordinates inputted by said pointing unit based on the angles chosen by said angle choosing unit.

2. The coordinate input apparatus according to claim 1, wherein said coordinate detection unit detects coordinates inputted by another pointing unit from angles which have not been chosen by the angle choosing unit when the number of angles detected during the present cycle is one greater than the number of angles of the immediately earlier cycle for said angle detection unit.

3. The coordinate input apparatus according to claim 1 further comprising an angle rejecting unit configured to reject angles which have not been chosen by the angle choosing unit when the number of angles detected during the present cycle by the angle detection unit is more than two greater than the number of angles detected during the immediately earlier cycle for said angle detection unit.

4. The coordinate input apparatus according to claim 1, wherein said angle detection unit comprises:

a light emitting unit,

a reflection unit recursively reflecting a light emitted by said light emitting unit,

a light receiving unit provided at a position where a light reflected at the reflection unit can be received, and

an optical unit configured to generate different positions of said light on the receiving unit in accordance with incident angles to the light receiving unit,

wherein the angle detection unit identifies straight lines connecting the point corresponding to the pointing unit and the reference points on the coordinate input face through points where the light receiving unit has not received a reflected light so as to detect the angles formed by said straight lines and the reference line on the coordinate input face.

5. The coordinate input apparatus according to claim 1, wherein said angle detection unit comprises an image input unit configured to take an image approximately on a whole area of the coordinate input face, identify the straight lines connecting the point corresponding to the pointing unit and the reference points on the coordinate input face through an image of the pointing unit taken by the image input unit, and detect the angles formed by the straight lines and the reference line on the coordinate input face.

6. A coordinate input apparatus comprising:

a coordinate input face where coordinates are inputted by a pointing unit,

a detection unit configured to periodically detect at least two angles formed by straight lines connecting a point corresponding to said pointing unit on said coordinate input face and reference points on said coordinate input face and a reference line on the coordinate input face,

an angle storing unit configured to store angles detected by the detection unit during an immediately earlier cycle among angles periodically detected,

an angle choosing unit configured to compare the angles detected during the immediately earlier cycle with angles detected during a present cycle, and to choose those angles detected during the present cycle that have a value most adjacent to a value of the angles detected during the immediately earlier cycle if a number of the angles detected during the present cycle is greater than a number of the angles detected during the immediately earlier cycle,

an identifier adding unit configured to add a first identifier to an angle chosen by the angle choosing unit, and

a coordinate detection unit configured to detect coordinates of the point corresponding to said pointing unit based on the angle detected by said angle detection unit, wherein

said coordinate detection unit detects the coordinates of said pointing unit which are continuous with coordinates which are based on the angles stored in the angle storing unit based on the angle to which said identifier adding unit has added the first identifier, and

said angle storing unit stores the angle to which the identifier adding unit has added the first identifier.

7. The coordinate input apparatus according to claim 6, wherein

said identifier adding unit adds a second identifier to an angle to which the first identifier has not been added when the number of angles detected during the present cycle by the angle detection unit is one greater than the number of angles detected during the immediate earlier cycle for said detection unit, and

said coordinate detection unit detects coordinates inputted by an other pointing unit based on the angle to which the second identifier has been added by the identifier adding unit.

8. The coordinate input apparatus according to claim 6 further comprising an angle data rejection unit configured to reject angle data to which the first identifier has not been added by the identifier adding unit when the number of angles detected during the present cycle by the angle detection unit is more than two greater than the number of angles detected during the immediately earlier cycle for said detection unit.

9. The coordinate input apparatus according to claim 6, wherein said angle detection unit comprises:

a light emitting unit,

a reflection unit recursively reflecting the light emitted by said light emitting unit,

a light receiving unit provided at a position where a light reflected at the reflection unit can be received, and

an optical unit configured to produce different positions of said light on the receiving unit in accordance with incident angles to the light receiving unit,

wherein the angle detection unit identifies straight lines connecting the point corresponding to the pointing unit and the reference points on the coordinate input face through points where the light receiving unit has not received a reflected light so as to detect the angles formed by said straight lines and the reference line on the coordinate input face.

10. The coordinate input apparatus according to claim 6, wherein said angle detection unit comprises an image input unit configured to take an image approximately on a whole area of the coordinate input face, identify the straight lines connecting the point corresponding to the pointing unit and the reference points on the coordinate input face through an image of the pointing unit taken by the image input unit, and detect the angles formed by the straight lines and the reference line on the coordinate input face.

11. A recording medium of a coordinate input apparatus in which a program is stored readable by a central processing unit of the coordinate input apparatus comprising a coordinate input face where coordinates are inputted by a pointing unit and a detection unit configured to periodically detect at least two angles formed by straight lines connecting a point corresponding to said pointing unit on said coordinate input face and reference points on said coordinate input face and a reference line on the coordinate input face, wherein said recording medium stores a program comprising:

storing angles detected during an immediately earlier cycle among angles periodically detected,

choosing angles detected during a present cycle that have a value most adjacent to a value of angles detected during the immediately earlier cycle if a number of the angles detected during the present cycle is greater than a number of angles detected during the immediately earlier cycle, and

detecting coordinates inputted by said pointing unit based on angles chosen by said choosing angles.

12. The recording medium according to claim 11 further comprising detecting coordinates inputted by another pointing unit based on angle data which have not been chosen in the choosing angles when the number of angles detected during the present cycle by the angle detection unit is one greater than the number of angles detected during the immediately earlier cycle for said angle detection unit.

13. The recording medium according to claim 11 further comprising rejecting angles which have not been chosen in the choosing angles when the number of angles detected during the present cycle by the angle detection unit is more than two greater than the number of angles detected during the immediately earlier cycle for said angle detection unit.

14. A recording medium of a coordinate input apparatus in which a program is stored readable by a central processing unit of the coordinate input apparatus comprising a coordinate input face where coordinates are inputted by a pointing unit, a detection unit configured to periodically detect at least two angles formed by straight lines connecting a point corresponding to said pointing unit on said coordinate input face and reference points on said coordinate input face and a reference line on the coordinate input face, and an angle storing unit configured to store angles detected during an immediately earlier cycle among angles periodically detected by the angle detection unit, wherein said recording medium stores a program comprising:

choosing angles detected during the present cycle that have a value most adjacent to a value of the angles detected during the immediately earlier cycle and stored in said angle storing unit among angles detected during the present cycle when a number of angles detected during the present cycle is greater than a number of angles detected during the immediately earlier cycle,

adding a first identifier to the angle chosen in the choosing angles,

detecting the coordinates of said pointing unit which are continuous with coordinates based on the angles stored in the storing angles based on the angle to which the first identifier has been added in said adding the first identifier, and

substituting and storing the angle to which the first identifier has been added in the adding the first identifier.

15. The recording medium according to claim 14 further comprising:

adding a second identifier to the angle to which the first identifier has not been added in the adding the first identifier; and

detecting coordinates inputted by another pointing unit based on the angle to which the second identifier has been added in the adding the second identifier when the number of angles detected during the present cycle by the angle detection unit is one greater than the number of angles detected during the immediately earlier cycle for said angle detection unit.

16. The recording medium according to claim 14 further comprising rejecting angle data to which the first identifier has not been added in the adding the first identifier when the number of angles detected during the present cycle by the angle detection unit is more than two greater than the number of angles detected during the immediately earlier cycle for said angle detection unit.