Coordinate position detecting apparatus and control method thereof

• US 20070052693A1
• Filed: 08/28/2006
• Published: 03/08/2007
• Est. Priority Date: 08/29/2005
• Status: Active Grant

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Watari, Haruo
• Granted Patent: US 7,903,097 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A coordinate position detecting apparatus includes: a scanning unit that scans a predetermined scanning area in predetermined scanning precision along a horizontal direction and a vertical direction with respect to a display screen by employing detection beams respectively. A position of a light shielding article on the display screen is detected in correspondence with scanning positions of the detection beams which are light-shielded. The scanning unit includes: a drive control unit that switches a plurality of scanning modes having different scanning accuracies from each other; and a moving speed detecting unit that detects a moving speed of the light shielding article. The scanning unit selects a predetermined scanning mode from the plurality of scanning modes in response to the scanning speed detected by the moving speed detecting unit to perform a scanning operation.

Claims

1. A coordinate position detecting apparatus, comprising:

a scanning unit that scans a predetermined scanning area in predetermined scanning precision along a horizontal direction and a vertical direction with respect to a display screen by employing detection beams respectively;

wherein a position of a light shielding article on the display screen is detected in correspondence with scanning positions of the detection beams which are light-shielded;

the scanning unit includes;

a drive control unit that switches a plurality of scanning modes having different scanning accuracies from each other; and

a moving speed detecting unit that detects a moving speed of the light shielding article; and

the scanning unit selects a predetermined scanning mode from the plurality of scanning modes in response to the scanning speed detected by the moving speed detecting unit to perform a scanning operation.

2. The coordinate position detecting apparatus as claimed in claim 1,

wherein the plurality of scanning mode includes one scanning mode in which an oblique scanning operation for detecting the position of the light shielding article is carried out such that a detection beam emitted from a light emitting element is received by a plurality of light receiving elements that are arranged opposite to positions including an oblique direction of the light emitting element.

3. The coordinate position detecting apparatus as claimed in claim 2,

wherein the plurality of the scanning modes include:

a first scanning mode for performing a grid-shaped scanning operation over an entire scanning area on the display screen;

a second scanning mode for performing the oblique scanning operation, while limiting a scanning area to a narrower range than the entire scanning area which contains a coordinate position detected in the first scanning mode; and

a third scanning mode for performing an oblique scanning operation under which a total number of the light receiving elements for detecting the detection beam emitted from a single light emitting element is smaller than that of the second scanning mode, while limiting a scanning area to a narrower range than the entire scanning area which contains a coordinate position detected in the first scanning mode.

4. The coordinate position detecting apparatus as claimed in claim 3,

wherein the plurality of scanning modes further includes a fourth scanning mode for limiting a scanning area to a narrower range than the entire scanning area which contains the coordinate position detected in the first scanning mode so as to perform the grid-shaped scanning operation within the limited scanning area.

5. A control method of a coordinate position detecting apparatus, wherein the coordinate position detecting apparatus scans a predetermined scanning area in a predetermined scanning accuracy along a horizontal direction and a vertical direction with respect to a display screen by employing detection beams respectively, and detects a position of a light shielding article on the display screen in correspondence with scanning positions of the detection beams which are light-shielded, the control method comprising:

performing a scanning in a first scanning mode until the light shielding article is detected; and

performing a scanning in a plurality of scanning mode that are different from the first scanning mode and that is selected in response to a moving speed of the light shielding article.

6. The control method as claimed in claim 5,

wherein the plurality of scanning mode includes one scanning mode in which an oblique scanning operation for detecting the position of the light shielding article is carried out such that a detection beam emitted from a light emitting element is received by a plurality of light receiving elements that are arranged opposite to positions including an oblique direction of the light emitting element.

7. The control method as claimed in claim 6,

wherein the step of performing a scanning in the first scanning mode includes a grid-shaped scanning operation that is carried out over an entire scanning area of the display screen until the light shielding article is detected;

the control method further includes;

calculating a moving speed of the light shielding article detected in the grid-shaped scanning operation; and

the step of performing a scanning in a plurality of scanning mode includes;

performing the oblique scanning operation in a second scanning mode when the calculated moving speed is lower than or equal to a predetermined speed, while limiting a scanning area to a narrower range than the entire scanning area including the coordinate position detected in the first scanning mode, and

performing the oblique scanning operation in a third scanning mode when the calculated moving speed is higher than the predetermined speed, the third scanning mode under which a total number of light receiving elements for detecting a detection beam emitted from a single light emitting element is smaller than that of the second scanning mode, while limiting a scanning area to a narrower range than the entire scanning area which contains a coordinate position detected in the first scanning mode.

8. The control method as claimed in claim 6 wherein:

wherein the step of performing a scanning in the first scanning mode includes a grid-shaped scanning operation that is carried out over an entire scanning area of the display screen until the light shielding article is detected;

the control method further includes;

calculating a moving speed of the light shielding article detected in the grid-shaped scanning operation; and

the step of performing a scanning in a plurality of scanning mode includes;

performing the oblique scanning operation in a second scanning mode when the calculated moving speed is lower than or equal to a first predetermined speed, while limiting a scanning area to a narrower range than the entire scanning area including the coordinate position detected in the first scanning mode,

performing the oblique scanning operation in a third scanning mode when the calculated moving speed exceeds the first predetermined speed and is lower than or equal to a second predetermined speed, the third scanning mode under which a total number of light receiving elements for detecting a detection beam emitted from a single light emitting element is smaller than that of the second scanning mode, while limiting a scanning area to a narrower range than the entire scanning area which contains a coordinate position detected in the first scanning mode, and

performing a scanning in a fourth scanning mode for limiting a scanning area to a narrower range than the entire scanning area which contains the coordinate position detected in the first scanning mode so as to perform the grid-shaped scanning operation within the limited scanning area

9. A program product for enabling a computer to control a coordinate position detecting apparatus, wherein the coordinate position detecting apparatus scans a predetermined scanning area in a predetermined scanning accuracy along a horizontal direction and a vertical direction with respect to a display screen by employing detection beams respectively, and detects a position of a light shielding article on the display screen in correspondence with scanning positions of the detection beams which are light-shielded, the program product comprising:

software instructions for enabling the computer to instruct the coordinate position detecting apparatus to perform predetermined operations; and

a computer readable medium bearing the software instructions;

wherein the predetermined operations includes;

performing a scanning in a first scanning mode until the light shielding article is detected; and

performing a scanning in a plurality of scanning mode that are different from the first scanning mode and that is selected in response to a moving speed of the light shielding article.