METHOD OF LOCATING TOUCH POSITION

• US 20120086672A1
• Filed: 12/17/2010
• Published: 04/12/2012
• Est. Priority Date: 10/08/2010
• Status: Abandoned Application

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Pai, Cheng-Chiu, Cho, An-Thung, Tseng, Hung-Wei, Tzeng, Shu-Wen
• Application Number:
  US12/970,971
• Publication Number:
  US 20120086672A1
• Time in Patent Office: Days
• US Class Current: 345/175
• 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 method for locating a touch position is provided. The method is adaptable to an optical touch panel, wherein the optical touch panel has a plurality of visible light sensors and a plurality of corresponding invisible light sensors that are arranged as an array. In the present method, sensing signals of the visible light sensors and the invisible light sensors are read. The sensing signal of each visible light sensor is converted into a first binary code according to a first setting parameter, and the sensing signal of each invisible light sensor is converted into a second binary code according to a second setting parameter and a third setting parameter. An AND operation is performed on all the first binary codes and all the second binary codes to obtain a plurality of logic operation values, so as to locate a position touched by a user on the optical touch panel.

Claims

1. A method of locating a touch position, adaptable to an optical touch panel, wherein the optical touch panel has a plurality of visible light sensors and a plurality of corresponding invisible light sensors that are arranged as an array, the method comprising:

reading sensing signals of the visible light sensors and the invisible light sensors;

converting the sensing signal of each of the visible light sensors into a first binary code according to a first setting parameter, and converting the sensing signal of each of the invisible light sensors into a second binary code according to a second setting parameter and a third setting parameter; and

performing a logic AND operation on all the first binary codes and all the second binary codes to obtain a plurality of logic operation values, so as to determine a position touched by a user on the optical touch panel.

2. The method according to claim 1, wherein when the logic operation values are all logic “

0”

, it is determined that the user does not touch the optical touch panel.

3. The method according to claim 1, wherein when a part of the logic operation values is logic “

1”

, it is determined that the user touches the optical touch panel.

4. The method according to claim 3, wherein the visible light sensors and invisible light sensors corresponding to all the logic operation values having logic “

1”

cover at least a touch area on the optical touch panel, and the method further comprises;

performing a center point operation on the touch area to obtain a touch parameter of the position touched by the user on the optical touch panel.

5. The method according to claim 4, wherein after performing the center point operation on the touch area, the method further comprises:

determining whether the touch area is larger than a predetermined area.

6. The method according to claim 5, wherein when the touch area is larger than the predetermined area, all the logic operation values having logic “

1”

are set to logic “

0”

, and when the touch area is not larger than the predetermined area, the touch parameter is output to trigger a corresponding operation of the optical touch panel.

7. The method according to claim 1, wherein when the sensing signals of the visible light sensors and the invisible light sensors are read, the method further comprises:

eliminating noises in the sensing signals of the visible light sensors and the invisible light sensors through a mean filtering technique.

8. The method according to claim 1, wherein before converting the sensing signals of the visible light sensors and the invisible light sensors, the method further comprises:

performing a remedy mechanism on the sensing signals of damaged visible light sensors and invisible light sensors.

9. The method according to claim 8, wherein the remedy mechanism comprises:

remedying the sensing signals of the damaged visible light sensors according to the sensing signals of a part of the undamaged visible light sensors; and

remedying the sensing signals of the damaged invisible light sensors according to the sensing signals of a part of the undamaged invisible light sensors.

10. The method according to claim 9, wherein

the part of the undamaged visible light sensors is adjacent to the damaged visible light sensors;

and

the part of the undamaged invisible light sensors is adjacent to the damaged invisible light sensors.

11. The method according to claim 10, wherein

the sensing signals of the remedied visible light sensors are at least interpolation values of the sensing signals of the part of the undamaged visible light sensors;

and

the sensing signals of the remedied invisible light sensors are at least interpolation values of the sensing signals of the part of the undamaged invisible light sensors.