Infrared touch screen gated by touch force

• US 8,130,202 B2
• Filed: 05/01/2007
• Issued: 03/06/2012
• Est. Priority Date: 05/01/2007
• Status: Active Grant

• Current Assignee: Toshiba Global Commerce Solutions Holdings Corporation (Toshiba Corporation)
• Original Assignee: International Business Machines Corporation
• Inventors: Levine, James L., Luerich, Susan A., Miller, Duane Scott
• Primary Examiner(s): Liang, Regina
• Application Number:
  US11/742,680
• Publication Number:
  US 20080273013A1
• Time in Patent Office: 1,771 Days
• Field of Search: 345173-179, 178 1801- 1809
• US Class Current: 345/173
• 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 touch-sensitive display device includes a display. A transparent plate is provided in front of the display. A tactile sensor senses a touch event. One or more infrared sensors are positioned in front of the transparent plate. The one or more infrared sensors identify a location of the touch event when the tactile sensor detects a touch event.

Claims

1. A touch-sensitive display device, comprising:

a display;

a transparent plate provided in front of the display device;

a single tactile sensor mounted in contact with the transparent plate to a side surface of the transparent plate, sensing a touch event; and

a plurality of infrared sensors and a plurality of corresponding infrared emitters positioned in front of the transparent plate, wherein the plurality of infrared sensors identify a location of the touch event when the tactile sensor detects a touch event and when the tactile sensor does not detect a touch event, each of the plurality of infrared emitters remains inactive,

wherein the single tactile sensor is mounted to the side surface of the transparent plate such that the single tactile sensor is beyond the range of perception of the plurality of infrared sensors.

2. The touch-sensitive display device of claim 1, wherein the display is an LCD panel.

3. The touch-sensitive display device of claim 1, wherein the transparent plate is mounted to allow the transparent plate to vibrate.

4. The touch-sensitive display device of claim 1, wherein the transparent plate is mounted to the touch-sensitive display device using double-sided foam tape.

5. The touch-sensitive display device of claim 1, wherein the transparent plate is an outer layer of the display.

6. The touch-sensitive display device of claim 1, wherein the transparent plate is a glass plate.

7. The touch-sensitive display device of claim 1, wherein the tactile sensor is a sensor that detects vibration, shock or displacement of the transparent plate.

8. The touch-sensitive display device of claim 1, wherein the tactile sensor is a piezoelectric sensor.

9. The touch-sensitive display device of claim 1, wherein the tactile sensor is in vibrational communication with the transparent plate.

10. The touch-sensitive display of claim 1, wherein the plurality of infrared sensors comprises a set of x-axis infrared sensors for detecting an x-axis coordinate of the touch event and a set of y-axis infrared sensors for detecting a y-axis coordinate of the touch event and the plurality of corresponding infrared emitters comprises a set of x-axis infrared emitters for emitting infrared light in the direction of the x-axis infrared sensors and a set of y-axis infrared emitters for emitting infrared light in the direction of the y-axis infrared sensors, wherein the coordinates of the touch event are detected based on the amount of infrared light detected by the respective infrared sensors.

11. A method for locating a touch event on a touch-sensitive display device, comprising:

monitoring a single tactile sensor mounted in contact with a side surface of a transparent plate provided in front of the touch-sensitive display device to detect the occurrence of a touch event;

when the occurrence of a touch event has been detected by the tactile sensor, identifying a location of the touch event based on a plurality of infrared sensors and a plurality of corresponding infrared emitters; and

when the occurrence of a touch event has not been detected by the tactile sensor, each of the plurality of infrared emitters remains inactive,

wherein the single tactile sensor is mounted to the side surface of the transparent plate such that the single tactile sensor is beyond the range of perception of the plurality of infrared sensors.

12. The method of claim 11, wherein the step of identifying a location of the touch event based on the plurality of infrared sensors and the plurality of corresponding infrared emitters comprises:

activating one or more infrared emitters of the plurality of corresponding infrared emitters;

reading the amount of infrared light detected by one or more infrared sensors of the plurality of infrared sensors; and

calculate the location of the touch event based on the amount of infrared light detected by each of the one or more infrared sensors and the relative position of each of the one or more infrared sensors.

13. The method of claim 11, wherein the tactile sensor detect the occurrence of a touch event by sensing vibration, shock or displacement of the touch-sensitive display device.

14. A method for retrofitting a touch-sensitive display, comprising:

affixing a single tactile sensor to the touch-sensitive display, comprising a display device, a transparent plate provided in front of the display device, and one or more infrared sensors positioned in front of the transparent plate for identifying a position of a touch event, such that the tactile sensor is in vibrational communication with the transparent plate of the touch-sensitive display, wherein the single tactile sensor is mounted in contact with a side surface of the transparent plate;

interfacing the tactile sensor to a microprocessor of the touch-sensitive display; and

modifying logic of the touch-sensitive display such that infrared sensors of the touch-sensitive display remain inactive until a tactile event is observed by the tactile sensor, and are activated when the tactile event is observed by the tactile sensor.

15. The method of claim 14, wherein the tactile sensor is a sensor that detects vibration, shock or displacement of the transparent plate.

16. The method of claim 14, wherein the tactile sensor is a piezoelectric sensor.

17. The method of claim 14, wherein the step of modifying the logic of the touch-sensitive display comprises changing or replacing computer-executable code executed by a microprocessor of the touch-sensitive display.

21. The method of claim 14, wherein the single tactile sensor is affixed to the side surface of the transparent plate such that the single tactile sensor is beyond the range of perception of the one or more infrared sensors.

18. A computer system comprising:

a processor; and

a program storage device readable by the computer system, embodying a program of instructions executable by the processor to perform method steps for locating a touch event on a touch-sensitive display device, the method comprising;

monitoring a single tactile sensor mounted in contact with a side surface of a transparent plate provided in front of the touch-sensitive display device to detect the occurrence of a touch event;

when the occurrence of a touch event has been detected by the tactile sensor, identifying a location of the touch event based on a plurality of infrared sensors and a corresponding plurality of infrared emitters; and

when the occurrence of a touch event has not been detected by the tactile sensor, each of the plurality of infrared emitters remains inactive,

wherein the single tactile sensor is mounted to the side surface of the transparent plate such that the single tactile sensor is beyond the range of perception of the plurality of infrared sensors.

19. The computer system of claim 18, wherein the step of identifying a location of the touch event based on the plurality of infrared sensors and the corresponding plurality of infrared emitters comprises:

activating one or more infrared emitters of the corresponding plurality of infrared emitters;

reading the amount of infrared light detected by one or more infrared sensors of the plurality of infrared sensors; and

calculate the location of the touch event based on the amount of infrared light detected by each of the one or more infrared sensors and the relative position of each of the one or more infrared sensors.

20. The computer system of claim 18, wherein the tactile sensor detect the occurrence of a touch event by sensing vibration, shock or displacement of the touch-sensitive display device.