Coordinate input apparatus and its control method

• US 20060012579A1
• Filed: 07/13/2005
• Published: 01/19/2006
• Est. Priority Date: 07/14/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sato, Hajime
• Granted Patent: US 7,746,326 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G02B 5/124 plural reflecting elements forming part of a unitary plate or sheet
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A coordinate input apparatus is provided. A photo transmission/reception unit includes a phototransmitter which projects light along a plane of an input region, and a photoreceptor which detects incoming light. A reflector is arranged on a rim portion of the input region, and reflects incident light from the phototransmitter toward the photoreceptor. A detection unit detects a shade formed by the pointing operation of a pointing device using the photo transmission/reception unit. And an output unit calculates a coordinate value of the position based on a state of the detected shade, and outputs information of the coordinate value. The pointing device includes a transmission unit configured to transmit a control signal including information of a unique identifier based on the pointing operation, and the output unit extracts the information of the identifier from the control signal transmitted based on the pointing operation associated with the shade, and appends the information of the coordinate value when that information is output.

Claims

1. A coordinate input apparatus comprising:

a photo transmission/reception unit having a phototransmitter which projects light along a plane of an input region, and a photoreceptor which detects incoming light;

a reflector which is arranged on a rim portion of the input region, and configured to reflect incident light from the phototransmitter in said photo transmission/reception unit toward the photoreceptor in that photo transmission/reception unit;

a pointing device used to make a pointing operation for pointing an arbitrary position in the input region;

a detection unit configured to detect a shade formed by the pointing operation of said pointing device using said photo transmission/reception unit; and

an output unit configured to calculate a coordinate value of the position on the basis of a state of the detected shade, and outputs information of the coordinate value,

wherein said pointing device includes a transmission unit configured to transmit a control signal including information of a unique identifier based on the pointing operation, and

said output unit extracts the information of the identifier from the control signal transmitted based on the pointing operation associated with the shade, and appends the information of the coordinate value when that information is output.

2. The apparatus according to claim 1, wherein said output unit includes a determination unit configured to determine the control signals corresponding to a plurality of shades when said detection unit detects the plurality of shades.

3. The apparatus according to claim 2, wherein said output unit skips a calculation of the coordinate value for the shade for which said determination unit determines that no corresponding control signal is detected.

6. The apparatus according to claim 1, further comprising a display device overlaid on the input region.

4. A method of controlling a coordinate input apparatus which has a photo transmission/reception unit having a phototransmitter which projects light along a plane of an input region, and a photoreceptor which detects incoming light, a reflector which is arranged on a rim portion of the input region, and configured to reflect incident light from the phototransmitter in the photo transmission/reception unit toward the photoreceptor in that photo transmission/reception unit, and a pointing device used to make a pointing operation for pointing an arbitrary position in the input region, the method comprising the step of:

detecting a shade formed by the pointing operation of the pointing device using the photo transmission/reception unit;

calculating a coordinate value of the pointed position on the basis of a state of the detected shade; and

extracting information of an identifier from a control signal transmitted based on the pointing operation associated with the shade, and appending the information of the coordinate value when that information is output.

5. A coordinate input apparatus comprising:

reception means for receiving a plurality of control signals transmitted by a plurality of pointing devices which point an arbitrary position in an input region, and transmits the control signal including information of a unique identifier;

detection means for detecting each position information of the plurality of pointing devices in accordance with each timing of the plurality of control signals received by said reception means; and

output means for associating the plurality of control signals received by said reception means with the position information detected by said detection means, and outputting the associated information.