Touch simulation system and method

• US 20040140993A1
• Filed: 01/17/2003
• Published: 07/22/2004
• Est. Priority Date: 01/17/2003
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Geaghan, Bernard O., Taylor, Gordon F., Field, Alan H.
• Granted Patent: US 7,362,313 B2
• Time in Patent Office: Days
• US Class Current: 345/702
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

Systems and methods provide for simulating an effective touch on a touch screen sensor. A touch screen sensor includes a first surface, an opposing second surface, and one or more electrodes disposed on or proximate to the second surface. Signals are applied to the first and second surfaces in a manner which results in a simulated touch to a particular location of the touch screen sensor. In another approach, a plurality of voltage drive signals are applied at various touch surface regions of the touch screen sensor. A current flow resulting from application of the voltage drive signals is detected as the simulated touch. Touch simulation can be initiated locally or remotely as part of automated monitoring, testing, calibration, and/or servicing procedures. Results of a touch simulation procedure can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.

Claims

1. A method for use with a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface, and an electrically conductive structure coupled to, or positioned proximate, the substrate and situated proximate the second surface, the method comprising:

applying a first signal to the first surface of the touch screen sensor;

applying a second signal to the conductive structure of the touch screen sensor; and

simulating a touch on the touch screen sensor by changing one of the first and second signals relative to the other of the first and second signals.

2. The method of claim 1, further comprising using the conductive structure as a shield against electrical noise.

3. The method of claim 1, wherein applying the first signal comprises applying the first signal at each of a plurality of corners of the first surface.

4. The method of claim 1, wherein the first and second signals comprise AC voltage signals.

5. The method of claim 1, wherein simulating the touch comprises changing an amplitude of the first signal relative to an amplitude of the second signal.

6. The method of claim 1, wherein simulating the touch comprises changing a phase of the first signal relative to a phase of the second signal.

7. The method of claim 1, wherein simulating the touch comprises changing a frequency of the first signal relative to a frequency of the second signal.

8. The method of claim 1, wherein simulating the touch comprises changing the first signal and maintaining the second signal substantially constant.

9. The method of claim 1, wherein simulating the touch comprises changing the second signal and maintaining the first signal substantially constant.

10. The method of claim 1, wherein simulating the touch comprises changing both the first signal and the second signal.

11. The method of claim 1, further comprising receiving an initiation signal, and initiating the respective applying and simulating processes in response to the received initiation signal.

12. The method of claim 11, wherein the initiation signal is generated during a predetermined touch screen sensor routine.

13. The method of claim 11, wherein the initiation signal is generated during a start-up or shut-down routine of the touch screen sensor.

14. The method of claim 1 wherein the initiation signal is generated during an extended period of non-use of the touch screen sensor while the touch screen sensor is in an operating mode.

15. The method of claim 1, further comprising generating a message signal associated with the simulated touch.

16. The method of claim 15, further comprising communicating the message signal to a remote location.

17. A method for use with a touch screen sensor having a first surface, a second surface opposing the first surface, and a plurality of electrodes disposed on or proximate to the second surface, the method comprising:

applying a first signal to the first surface of the touch screen sensor;

applying one of a plurality of second signals to each of the plurality of electrodes disposed on or proximate to the second surface of the touch screen sensor; and

simulating a touch on the touch screen sensor by changing a characteristic of at least one of the plurality of second signals relative to the first signal.

18. The method of claim 17, wherein the characteristic comprises an amplitude of the at least one of the plurality of second signals.

19. The method of claim 17, wherein the characteristic comprises amplitude, and the plurality of second signals have substantially equal amplitudes.

20. The method of claim 17, wherein the characteristic comprises amplitude, and the at least one of the plurality of second signals has an amplitude differing from an amplitude of others of the plurality of second signals.

21. The method of claim 17, wherein the characteristic comprises a frequency of the at least one of the plurality of second signals.

22. The method of claim 17, wherein the characteristic comprises frequency, and the plurality of second signals have substantially equal frequencies.

23. The method of claim 17, wherein the characteristic comprises frequency, and the at least one of the plurality of second signals has a frequency differing from a frequency of others of the plurality of second signals.

24. The method of claim 17, wherein the characteristic comprises a phase of the at least one of the plurality of second signals.

25. The method of claim 17, wherein the characteristic comprises phase, and the plurality of second signals have substantially equal phase.

26. The method of claim 17, wherein the characteristic comprises phase, and the at least one of the plurality of second signals has a phase differing from a phase of others of the plurality of second signals.

27. The method of claim 17, wherein applying the first signal comprises applying the first signal at each of a plurality of corners of the first surface.

28. A method for use with a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface, and an electrically conductive structure coupled to, or positioned proximate, the substrate and situated proximate the second surface, the method comprising:

developing a potential difference between the first surface and conductive structure of the touch screen sensor; and

detecting a response to the potential difference as the simulated touch.

29. The method of claim 28, wherein developing the potential difference comprises:

applying first and second voltage signals of substantially equal amplitude respectively to the first surface and conductive structure during an operational mode of the touch screen sensor; and

changing one or both of the first and second voltage signal amplitudes to develop the potential difference between the first surface and conductive structure.

30. The method of claim 28, wherein developing the potential difference comprises applying a first AC voltage signal and a second AC voltage signal respectively to the first surface and conductive structure.

31. The method of claim 28, wherein developing the potential difference comprises varying a first voltage signal applied to the first surface and maintaining a second voltage signal applied to the conductive structure substantially constant.

32. The method of claim 31, wherein the second voltage signal comprises a DC voltage signal.

33. The method of claim 28, wherein developing the potential difference comprises varying a first voltage signal applied to the first surface and varying a second voltage signal applied to the conductive structure.

34. The method of claim 28, wherein detecting the response comprises detecting a change in currents detected at each of a plurality of locations of the first surface.

35. The method of claim 28, wherein detecting the response to the potential difference comprises detecting a current at each of a plurality of corners of the first surface, and converting each of the currents to corresponding values.

36. The method of claim 28, further comprising associating the detected response to the potential difference with a position of the simulated touch on the touch screen sensor.

37. The method of claim 28, further comprising receiving an initiation signal, and initiating the developing and detecting processes in response to the received initiation signal.

38. The method of claim 37, wherein the initiation signal is received from one of a remote location and a location proximate the touch screen sensor.

39. The method of claim 37, wherein the initiation signal is generated during a predetermined touch screen sensor routine.

40. A method of simulating a touch on a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface, the method comprising:

applying a plurality of voltage drive signals at a plurality of regions of the touch screen sensor; and

detecting a current flow resulting from application of the plurality of voltage drive signals as the simulated touch.

41. The method of claim 40, wherein the voltage drive signals have substantially equal amplitudes.

42. The method of claim 40, wherein at least one of the voltage drive signals has an amplitude differing from others of the plurality of voltage drive signals.

43. The method of claim 40, wherein detecting the current flow comprises detecting a change in a current flow at each of a plurality of corner regions of the first surface.

44. The method of claim 40, further comprising detecting an impedance change between one corner region of the first surface relative to other corner regions of the first surface.

45. The method of claim 40, wherein the voltage drive signals are applied to first, second, third, and fourth corners of the first surface, the first and second corners opposing the third and fourth corners, the method further comprising adjusting each of the voltage drive signals to a predetermined amplitude, and detecting an impedance responsive to the adjusted voltage drive signals.

46. The method of claim 45, wherein the predetermined amplitude of the voltage drive signals respectively applied to the first and second corners is different from the predetermined amplitude of the voltage drive signals respectively applied to the third and fourth corners.

47. The method of claim 40, wherein the applying and detecting processes are repeated over a duration of time, the method further comprising detecting variations in the current flow over the duration of time.

48. The method of claim 40, wherein the applying and detecting processes are repeated over a duration of time, the method further comprising detecting a change in a position of the simulated touch over the duration of time.

49. The method of claim 48, further comprising generating a message signal associated with the detected change in simulated touch position, and communicating the message signal to a remote location.

50. The method of claim 40, further comprising receiving an initiation signal, and initiating the applying and detecting processes in response to the received initiation signal.

51. The method of claim 50, wherein the initiation signal is received from a remote location or a location proximate the touch screen sensor.

52. The method of claim 50, wherein the initiation signal is generated during a predetermined touch screen sensor routine.

53. The method of claim 40, wherein a result of the simulated touch is compared to one or more predetermined limits, and the result exceeding the one or more predetermined limits is used to assess operational fitness of the touch screen sensor.

54. The method of claim 40, wherein a current result of the simulated touch is compared to one or more previously measured results of the simulated touch, and the current result deviating from the previously measured results by a predetermined amount is used to assess operational fitness of the touch screen sensor.

55. The method of claim 40, wherein a result of the simulated touch is used to compensate for inaccuracies of the touch screen sensor or a system incorporating the touch screen sensor.

56. A touch sensing system, comprising:

a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface;

an electrically conductive structure coupled to, or positioned proximate, the substrate and situated proximate the second surface; and

a controller coupled to the touch screen sensor, the controller configured to apply first and second signals respectively to the first surface of the touch screen sensor and the electrically conductive structure, the controller configured to simulate a touch on the touch screen sensor by changing one of the first and second signals relative to the other of the first and second signals.

57. The system of claim 56, wherein the electrically conductive structure acts as a shield against electrical noise.

58. The system of claim 56, wherein the first and second signals comprise AC voltage signals.

59. The system of claim 56, wherein the controller simulates the touch by changing an amplitude of the first signal relative to an amplitude of the second signal.

60. The system of claim 56, wherein the controller simulates the touch by changing a phase of the first signal relative to a phase of the second signal.

61. The system of claim 56, wherein the controller simulates the touch by changing a frequency of the first signal relative to a frequency of the second signal.

62. The system of claim 56, wherein application of the fist and second signals by the controller develops a potential difference between the first surface and the electrically conductive structure of the touch screen sensor, the controller detecting a response to the potential difference as the simulated touch.

63. The system of claim 56, further comprising a host computing system having a display, wherein the touch screen sensor is coupled to the display and the controller is communicatively coupled to the host computing system.

64. The system of claim 63, wherein the controller receives an initiation signal from the host processing system, and initiates the respective applying and simulating processes in response to the received initiation signal.

65. The system of claim 64, wherein the host processing system receives a touch simulation command signal from a remote source, the host processing system generating the initiation signal in response to the touch simulation command signal.

66. The system of claim 56, wherein the controller receives an initiation signal from a remote source, the controller initiating the respective applying and simulating processes in response to the received initiation signal.

67. The system of claim 66, wherein the initiation signal is generated during a predetermined touch screen sensor routine or a period of system idleness.

68. The system of claim 56, wherein the controller or a host processing system coupled to the controller generate a message signal associated with the simulated touch.

69. The system of claim 56, wherein the message signal is communicated to a remote location via a communication link.

70. A touch sensing system, comprising:

a touch screen sensor having a first surface, a second surface opposing the first surface, and a plurality of electrodes disposed on or proximate to the second surface; and

a controller coupled to the touch screen sensor, the controller configured to apply a first signal to the first surface of the touch screen sensor and applying one of a plurality of second signals to each of the plurality of electrodes disposed on or proximate to the second surface of the touch screen sensor, the controller configured to simulate a touch on the touch screen sensor by changing a characteristic of at least one of the plurality of second signals relative to the first signal.

71. The system of claim 70, wherein the controller simulates the touch by changing an amplitude of the at least one of the plurality of second signals.

72. The system of claim 70, wherein the characteristic comprises amplitude, and the controller maintains the plurality of second signals at substantially the same amplitude while changing an amplitude of the fist signal.

73. The system of claim 70, wherein the characteristic comprises amplitude, and the controller adjusts an amplitude of at least one of the plurality of second signals to an amplitude differing from an amplitude of others of the plurality of second signals.

74. The system of claim 70, wherein the controller simulates the touch by changing a frequency of the at least one of the plurality of second signals.

75. The system of claim 70, wherein the characteristic comprises frequency, and the controller maintains the plurality of second signals at substantially the same frequency.

76. The system of claim 70, wherein the characteristic comprises frequency, and the controller adjusts a frequency of at least one of the plurality of second signals to a frequency differing from a frequency of others of the plurality of second signals.

77. The system of claim 70, wherein the controller simulates the touch by changing a phase of the at least one of the plurality of second signals.

78. The system of claim 70, wherein the characteristic comprises phase, and the controller maintains the plurality of second signals at substantially the same phase.

79. The system of claim 70, wherein the characteristic comprises phase, and the controller adjusts a phase of at least one of the plurality of second signals to a phase differing from a phase of others of the plurality of second signals.

80. A touch sensing system, comprising:

a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface; and

a controller coupled to the touch screen sensor, the controller configured to apply a plurality of voltage drive signals at a plurality of regions of the touch screen sensor, and detect a current flow resulting from application of the plurality of voltage drive signals as the simulated touch.

81. The system of claim 80, wherein the controller maintains the voltage drive signals at substantially equal amplitudes.

82. The system of claim 80, wherein the controller adjusts the amplitude of at least one of the voltage drive signals to an amplitude differing from an amplitude of others of the plurality of voltage drive signals.

83. The system of claim 80, wherein the controller detects the current flow by detecting a change in a current flow at each of a plurality of corner regions of the first surface.

84. The system of claim 80, wherein the controller detects an impedance change between one corner region of the first surface relative to other corner regions of the first surface.

85. The system of claim 80, wherein the controller applies the voltage drive signals to first, second, third, and fourth corners of the first surface, the first and second corners opposing the third and fourth corners, the controller adjusting each of the voltage drive signals to a predetermined amplitude, and detecting an impedance responsive to the adjusted voltage drive signals.

86. The system of claim 85, wherein the predetermined amplitude of the voltage drive signals respectively applied to the first and second corners is different from the predetermined amplitude of the voltage drive signals respectively applied to the third and fourth corners.

87. The system of claim 80, wherein the controller repeats the applying and detecting processes over a duration of time, the controller detecting variations in the current flow over the duration of time.

88. The system of claim 80, wherein the controller repeats the applying and detecting processes over a duration of time, the controller detecting a change in a position of the simulated touch over the duration of time.

89. The system of claim 88, wherein the controller or a host processing system coupled to the controller generates a message signal associated with the detected change in simulated touch position, the message signal communicated to a remote location.

90. The system of claim 80, wherein the controller receives an initiation signal from a remote source or a host processing system coupled to the controller, and controller initiating the applying and detecting processes in response to the received initiation signal.

91. The system of claim 90, wherein the initiation signal is generated during a predetermined touch screen sensor routine or during a period of detected system idleness.

92. The system of claim 80, wherein a result of the simulated touch is compared to one or more predetermined limits, and the result exceeding the one or more predetermined limits is used to assess operational fitness of the touch screen sensor.

93. The system of claim 80, wherein a current result of the simulated touch is compared to one or more previously measured results of the simulated touch, and the current result deviating from the previously measured results by a predetermined amount is used to assess operational fitness of the touch screen sensor.

94. The system of claim 80, wherein a result of the simulated touch is used to compensate for inaccuracies of the touch screen sensor or a system incorporating the touch screen sensor.