TOUCH SIMULATION SYSTEM AND METHOD
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.
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This application is a divisional of U.S. Ser. No. 10/346,325, filed Jan. 17, 2003, now allowed, the disclosure of which is incorporated by reference in its entirety herein.
FIELD OF THE INVENTIONThe present invention relates generally to touch screen sensors and, more particularly, to systems and methods for simulating an effective human touch on a touch screen sensor.
BACKGROUND OF THE INVENTIONA typical touch screen employs a sheet of glass with a conductive coating, such as indium tin oxide, with four corner terminal connections. The touch screen may be configured as a capacitive or resistive touch screen, with a pattern of electrodes made of conductive material. A finger, stylus, or conductive top sheet can draw or inject current at the point of contact. The current can then distribute to the touch panel terminals in a proportionate manner relative to the location of the point of contact.
Touch detection accuracy of the touch screen can change over time due to a number of system and environmental reasons, such as wear during extended use. Monitoring, testing, and servicing of touch screen systems has conventionally involved manual evaluation of a suspect system by an on-site technician. Such conventional evaluation and repair approaches are both costly and time inefficient.
SUMMARY OF THE INVENTIONThe present invention is directed to systems and methods for simulating an effective touch on a touch screen sensor. According to one embodiment, a touch screen sensor includes a first surface, a second surface opposing the first 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. According to another embodiment, a plurality of voltage drive signals are applied at a plurality of 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.
In accordance with a further embodiment, a touch screen sensor includes 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. First and second signals are respectively applied to the first surface of the touch screen sensor and the electrically conductive structure. A touch on the touch screen sensor is simulated by changing one of the first and second signals relative to the other of the first and second signals. For example, the first and second signals are respectively applied to the first surface and electrically conductive structure to develop a potential difference between the first surface and the electrically conductive structure. A response to the potential difference is detected as the simulated touch.
According to another embodiment, a touch screen sensor includes a first surface, a second surface opposing the first surface, and a plurality of electrodes disposed on or proximate to the second surface. A first signal is applied to the first surface of the touch screen sensor. One of a plurality of second signals is applied to each of the plurality of electrodes disposed on or proximate to the second surface of the touch screen sensor. A touch on the touch screen sensor is simulated by changing a characteristic of at least one of the plurality of second signals relative to the first signal.
In accordance with a further embodiment, a touch sensing system includes a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface. The system further includes an electrically conductive structure coupled to, or positioned proximate, the substrate and situated proximate the second surface. A controller is coupled to the touch screen sensor. The controller is configured to apply first and second signals respectively to the first surface of the touch screen sensor and the electrically conductive structure. The controller simulates 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.
According to another embodiment, a touch sensing system includes 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. A controller, coupled to the touch screen sensor, is configured to apply a first signal to the first surface of the touch screen sensor and apply 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 simulates 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.
In accordance with yet another embodiment, a touch sensing system includes a touch screen sensor comprising a substrate having a first surface and a second surface opposing the first surface. A controller, coupled to the touch screen sensor, is configured to apply a plurality of voltage drive signals at a plurality of regions of the touch screen sensor. The controller detects a current flow resulting from application of the plurality of voltage drive signals 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, such as current and historical touch detection accuracy data, can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.
The above summary of the present invention is not intended to describe each embodiment or every implementation of the present invention. Advantages and attainments, together with a more complete understanding of the invention, will become apparent and appreciated by referring to the following detailed description and claims taken in conjunction with the accompanying drawings.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It is to be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTSIn the following description of the illustrated embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration, various embodiments in which the invention may be practiced. It is to be understood that the embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.
The present invention is directed to systems and methods for simulating a touch on a touch screen sensor. Simulating a touch on a touch screen sensor (TSS) can involve processes effected from, or performed at, a remote site, such as initiating, monitoring, analyzing, or controlling a touch simulation process. Touch simulation methodologies implemented in accordance with the principles of the present invention provide for enhanced diagnostic, calibration, and maintenance capabilities that can be used across a number of differing touch screen sensor technologies, including, for example, capacitive, resistive, and hybrid capacitive/resistive TSS technologies.
It has been found that changes in touch detection accuracy can result during extended use of a given touch screen sensor. For example, changes in the coordinates detected by a given touch screen sensor can result in touch detection inaccuracies resulting from wear, environmental factors, or characteristics of a particular application or system in which the touch screen sensor is implemented. It is important that any such changes in TSS detection accuracy and overall TSS performance be monitored so that recalibration or maintenance on the touch screen systems can be initiated when necessary. Traditionally, a skilled technician typically gathers such data by performing on-site servicing to the touch screen system, often after TSS performance has significantly degraded to a level that adversely impacts use of the system.
A touch simulation approach according to the present invention provides for enhanced monitoring of touch screen sensor performance in a manner that can eliminate the need for on-site testing and servicing by a skilled technician in many cases. Certain embodiments of the present invention provide for local initiation of touch screen sensor diagnostic and calibration tests that involve the simulation of a touch by the TSS controller or a host computing system which incorporates a touch screen sensor. Other embodiments of the present invention provide for remote initiation of touch screen sensor diagnostic and calibration tests that involve the simulation of a touch by the TSS controller or a host computing system which incorporates a touch screen sensor.
Touch simulation in accordance with the present invention can be initiated by software executable by a host computing system which incorporates a touch screen system or by software/firmware executable by a TSS controller. The touch simulation software can be controller locally or remotely via a network connection, for example, preferably at off-peak times, during periods of TSS idleness, or during regularly scheduled maintenance. Each time a touch is simulated, the detected position of the touch can be recorded locally, such as on the host computing system, and stored in a file or database. Over a period of time, changes in the value of the recorded touch can be tracked. Trends can be monitored and, if necessary, maintenance alert messages can be issued. Various operations implicated in TSS monitoring, evaluation, and repair can be performed locally, remotely, or cooperatively via local and remote resources.
An automated touch simulation approach of the present invention provides for a highly repeatable touch that can be simulated at a prescribed screen location with high accuracy. The ability to simulate a touch at a prescribed location with high precision provides for a high resolution of touch detection accuracy. It can be appreciated that human touches made at a prescribed calibration location of a touch screen, for example, can be subject to significant positional inaccuracies, since a repeated human touch rarely occurs in the same location.
Another source of inaccuracies that can adversely affect conventional TSS monitoring and testing approaches involves intended or unintended adjustment to video position, size, and horizontal and vertical dimensions of the display (e.g., cathode ray tube) to which the touch screen sensor is attached. A touch target on the display will move if changes are made to these parameters. When a human uses a predetermined touch target of the display to test for touch coordinate movement, repeatability is virtually impossible.
Touch simulation methodologies of the present invention find utility in a wide variety of applications. For example, entertainment systems can be installed in public locations, such as in arcades, casinos, and bars, where accuracy of touch is essential. At off peak times, or during system startup or shutdown or other predetermined times, a background maintenance program involving a simulated touch can be run, and any changes in touch position can be recorded. Changes over time to the touch position can be monitored, and significant variations can be reported to an operator or owner for servicing. A service engineer can, for example, initiate background maintenance remotely on demand over a computer network or on site. Such background maintenance routines can also be initiated locally or remotely according to a scheduled maintenance program, which may be during periods of detected system idleness or during system startup or shutdown, for example.
A technician can remotely access the TSS system via a network or dial-up connection. By way of example, the TSS system can be accessed via a communication link established between a remote computing system and the controller of the TSS system, assuming the TSS system includes an appropriate communications interface. Alternatively, or in addition, the TSS system can be accessed via a communication link established between the remote computing system and the communications interface of a host computing system which incorporates a TSS system.
Turning now to
It is understood that the TSS 22 can be implemented as a device separate from, but operative with, a display 24 of the host computing system 28. Alternatively, the TSS 22 can be implemented as part of a unitary system which includes a display device, such as a plasma, LCD, or other type of display technology amenable to incorporation of the TSS 22. It is further understood that utility is found in a system defined to include only the TSS 22 and controller 26 which, together, can implement a touch simulation methodology of the present invention.
In the illustrative configuration shown in
In one particular configuration, for example, the host computing system 28 is configured to support an operating system and touch screen driver software. The host computing system 28 can further support utility software and hardware. For example, software can be stored on the host computing system 28 which can be executed to calibrate the touch screen sensor 22 and to configure or setup the TSS 22. It will be appreciated that the various software/firmware and processing devices used to implement touch screen sensor processing and functionality in accordance with the principles of the present invention can be physically or logically associated with the TSS controller 26, host computing system 28, a remote processing system, or distributed amongst two or more of the controller 26, host computing system 28, and remote processing system.
The controller 26, which may be mounted to a separate card and removably installable within the host computing system chassis, typically includes processor and memory devices for storing and executing TSS operating firmware and communication firmware for communicating with the host computing system 28. The TSS 22 can be attached to the display 24 and include a connector interface for connecting with the controller 26.
In
The host computing system 28 further includes one or more media drives 38 which are configured to access (read and/or write) appropriate portable media 40. For example, the media drives 38 may includes one or more of a CD-ROM reader/writer, DVD drive, floppy drive, memory card reader/writer or other type of media drive. The host computing system 28 can also include a mass storage device 36, such as a direct access storage device (e.g., hard drive) or other form of non-volatile digital memory, and system memory 34.
In the configuration shown in
The remote system 46 can interact with the host computing system 28 in a wide variety of manners depending on the desired level of services and functionality required for a given application. Such services and functionality can include one or more of remote control of the host computing system 28 and/or TSS controller 26, remote touch simulation, remote monitoring, remote diagnostics, remote calibration, and remote servicing/repair, for example. In most configurations, bi-directional communication is effected between the remote system 46 and the communication interface 32. It is understood, however, that in certain system configurations, it may only be necessary or desired to provide for uni-directional communication between the remote system 46 and the host computing system 28.
Referring now to
According to another configuration, the remote signal 50 is communicated directly between the remote system 46 and TSS controller 26. The remote signal 50 is transmitted and/or received by the TSS controller 26 via link 50B. In this configuration, the TSS controller 26 is directly linked with the remote system 46 via link 50B. The TSS 26 can communicate with the host computing system 28 over an appropriate connection (e.g., link 50C) if such is needed or desired to support TSS services and functionality. In yet another configuration, the remote signal 50 can be selectively directed to one or both of the host computing system 28 and TSS controller 26 via links 50A and 50B depending on the nature of the remote signal 50 and other considerations.
Turning now to
The TSS 70 is shown to include four corner terminals 74, 76, 78, 80 to which respective wires 74a, 76a, 78a, 80a are attached. Each of the wires 74a, 76a, 78a, 80a is coupled to the TSS controller 75. The wires 74a, 76a, 78a, 80a connect their respective corner terminals 74, 76, 78, 80 with respective drive/sense circuits 74b, 76b, 78b, 80b provided in the controller 75. An additional wire 73a connects a terminal (not shown) disposed on the rear surface 73 with a drive/sense circuit 73b in the controller 75.
The controller 75 controls the voltage at each of the corner terminals 74, 76, 78, 80 and the rear terminal via drive/sense circuits 74b, 76b, 78b, 80b, 73b to maintain a desired voltage on the top and rear surfaces 72, 73. During normal operation, the controller 75 maintains the top and rear surface voltages at substantially the same voltage. A finger or stylus touch force applied to the top surface 72 is detected as an effective small capacitor applied to the top surface 72. The location of the touch on the top surface 72 is determined by current flow measurements made by the controller 75 via corner drive/sense circuits 74b, 76b, 78b, 80b in a manner known in the art.
In accordance with the principles of the present invention, the controller 75 can control the drive/sense circuits 74b, 76b, 78b, 80b, and 73b in a variety of manners in order to simulate a touch on the touch screen sensor 70. As will be described in greater detail, touch simulation can be initiated, monitored, and controlled locally and/or remotely.
According to one approach, the controller 75 simulates the effect of a touch to TSS 70 by adjusting the top and rear surface voltages to develop a potential difference between the top and rear surfaces 72, 73. Developing a potential difference in this manner forces a capacitive effect between the top and rear surfaces 72, 73, which is detected by current flow measurements made at the four corner terminals 74, 76, 78, 80 by the controller 75.
For example, the top surface 72 can be maintained at a nominal operating voltage and the voltage of rear surface 73 can be reduced from the nominal operating voltage, such as to about 0 V for example. The capacitive effect resulting from the potential difference developed between the top and rear surfaces 72, 73 is detected as an effective or simulated touch located approximately at the center of the top surface 72. When this touch simulation process is repeated over time, changes in the detected location of the simulated touch can indicate changes in the accuracy of the touch screen sensing system.
In
In normal operation, drive signals are applied to the corner terminals 134, 135, 136, 137 via respective drive circuits in the controller, and the controller measures currents flowing through the corner terminals 134, 135, 136, 137 via respective sense circuits in the controller. Touch position is then calculated from the measured currents using known methods.
The corner terminals 134, 135, 136, 137 are typically driven with an AC voltage, and the linearization electrodes 132 distribute the voltage evenly across the top resistive layer 144. The rear electrode 142 and rear resistive layer 143 are typically driven with an AC voltage equal to and in phase with the voltage driving corner terminals 134, 135, 136, 137. As such, the rear resistive layer 143 serves as a shield against noise and also minimizes parasitic capacitance effects because negligible capacitive current flows from top resistive layer 144 to rear resistive layer 143. If the voltage on the rear resistive layer 143 is made unequal to that on the top resistive layer 144, an equal change in current flow at corner terminals 134, 135, 136, 137 will result in an apparent touch to the center of the top surface 140 of TSS 130. This simulated touch can be used for diagnostic, calibration, and repair purposes, such as those described herein.
According to a variation of the touch screen sensor configuration depicted in
In a configuration in which multiple rear electrodes are employed, as is the embodiment shown in
In a diagnostic mode, touch simulation can be effected by varying a number of drive signal parameters, such as amplitude, phase, and frequency, relative to one another. According to one approach, and as illustrated in
For example, and with reference to
By way of example, rear electrodes 252 and 254 can be undriven, while rear electrode 251 is driven with a voltage out of phase with the voltage applied to corner terminals 234, 235, 236, 237 on the top surface 240, and rear electrode 253 can be driven with a voltage in phase with the voltage applied to the corner terminals 234, 235, 236, 237. In this illustrative example, a simulated touch will be located at point 260 shown in
Independent rear electrodes, such as rear electrodes 251, 252, 253, 254 shown in
In accordance with another approach, a non-capacitive technique can be employed to simulate a touch on a touch screen sensor. In a system such as that shown in
By way of example, and with particular reference to
For example, the controller can increase the drive voltage on all four corner terminals 234, 235, 236, 237 on the top surface 240 to simulate a touch to point 61 at the center of TSS 250. The controller can also increase the drive voltage on corner terminals 235 and 236 relative to the drive signals applied to corner terminals 234 and 237, while maintaining a constant touch detect threshold. This will result in a simulated touch at point 260.
Referring now to
In the embodiments shown in
In the embodiment shown in
According to one touch simulation approach, and as depicted in flow diagram form in
As was described previously, the controller can simulate a centered or non-centered touch on the TSS substrate 305 by varying one or more parameters of the first and second signals, including one or more of the amplitude, phase, and frequency of the drive signals. For example, and with reference to
As is shown in the embodiment illustrated in
For example, a change detected in a particular TSS parameter can be compared 416 to a predetermined limit or result established from a previously measured touch simulation limit or result. The comparison operation can be performed locally, remotely 418, or cooperatively at local and remote sites. Results from a diagnostics procedure performed at the touch screen sensor can be stored and reports generated 420 locally and/or at the remote site.
As was discussed previously, touch simulation methodologies of the present invention can be implemented in a wide range of touch screen sensor technologies. By way of further example, touch simulation methodologies in accordance with the present invention can be implemented in a near field imaging (NFI) capacitive touch screen sensor. A simplified schematic of an NFI capacitive touch screen sensor is illustrated in
The NFI capacitive touch screen sensor includes conductive ITO (indium-tin-oxide) bars 515 through 534, deposited on substrate 501, which define the touch sensitive surface. Bar connections 540 through 548 connect the ITO bars to an electronic controller (not shown).
A touch is detected by activating bars 515-534 with an AC signal, and measuring changes in current flowing in connections 540-548 due to capacitive coupling from one or more bars to a finger or stylus in proximity to the bar(s). Vertical position is determined by the relative magnitude of the change in current among the bars. Horizontal position is determined by measuring the ratio of current change in a bar between its left side connection (540-543) and its right side connection (544-548). Additional details of an NFI capacitive touch screen sensor of the type depicted in
A touch may be simulated by driving one of the left side simulation electrodes 505, 506 and one of the right side simulation electrodes 507, 508 with a signal that is unequal to the signals driven onto lines 540-548. Simulation electrodes may be grounded, or driven with an AC signal that is a different magnitude or out of phase with the signals on lines 540-548. For example, grounding electrodes 505 and 507 will result in a simulated touch in the center of bar 515. Driving electrode 517 with an AC signal equal in magnitude and in phase with the signals on lines 540-548, while grounding electrode 505, results in a simulated touch near the left end of bar 515. Grounding electrodes 505 and 508 simulates a touch to the center of bar 531.
Another touch screen sensor of a technology amenable to automated touch simulation is a grid capacitive touch screen sensor.
Touch simulation on this type of touch screen sensor is similar to that associated with NFI capacitive touch screen sensors, in that a simulation electrode 700, 701, 702, 703 near one of the touch electrodes 652-667 or near the electrode connections 670-685 may be grounded or driven with a signal that will couple to touch electrodes and change the electrode's impedance to simulate a touch. Only four simulation electrodes are shown in
As an alternative to simulation electrodes constructed on or near the touch sensor, capacitive coupling to touch electrodes 652-667 or electrode connections 670-685 may be accomplished by connecting standard capacitors to electrode connections 670-685. Such capacitors may be located on the sensor or its cable, or on the electronic controller that generates the signals that drive the sensor.
The foregoing description of the various embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
Claims
1. 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.
2. The method of claim 1, wherein the voltage drive signals have substantially equal amplitudes.
3. The method of claim 1, wherein at least one of the voltage drive signals has an amplitude differing from others of the plurality of voltage drive signals.
4. The method of claim 1, 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.
5. The method of claim 1, further comprising detecting an impedance change between one corner region of the first surface relative to other corner regions of the first surface.
6. The method of claim 1, 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.
7. The method of claim 6, 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.
8. The method of claim 1, 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.
9. The method of claim 1, 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.
10. The method of claim 9, further comprising generating a message signal associated with the detected change in simulated touch position, and communicating the message signal to a remote location.
11. The method of claim 1, further comprising receiving an initiation signal, and initiating the applying and detecting processes in response to the received initiation signal.
12. The method of claim 11, wherein the initiation signal is received from a remote location or a location proximate the touch screen sensor.
13. The method of claim 11, wherein the initiation signal is generated during a predetermined touch screen sensor routine.
14. The method of claim 1, 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.
15. The method of claim 1, 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.
16. The method of claim 1, 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.
17. 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.
18. The system of claim 17, wherein the controller maintains the voltage drive signals at substantially equal amplitudes.
19. The system of claim 17, 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.
20. The system of claim 17, 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.
21. The system of claim 17, wherein the controller detects an impedance change between one corner region of the first surface relative to other corner regions of the first surface.
22. The system of claim 17, 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.
23. The system of claim 22, 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.
24. The system of claim 17, 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.
25. The system of claim 17, 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.
26. The system of claim 25, 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.
27. The system of claim 17, 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.
28. The system of claim 27, wherein the initiation signal is generated during a predetermined touch screen sensor routine or during a period of detected system idleness.
29. The system of claim 17, 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.
30. The system of claim 17, 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.
31. The system of claim 17, 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.
Type: Application
Filed: Feb 28, 2008
Publication Date: Sep 4, 2008
Applicant:
Inventors: Bernard O. GEAGHAN (Salem, NH), Gordon F. Taylor (Bolton, MA), Alan H. Field (Topsfield, MA)
Application Number: 12/038,834