Abstract: Methods and devices for determining the location of a touch implement relative to a touch locating sensing device involve developing touch signals at a touch sensor in response to a touch implement on or near the touch surface. Data associated with the touch signals is fitted to a predefined curve. The predefined curve is preferably defined by a charged sphere near a conducting plane, the charged sphere representative of an end of the touch implement and the conducting plane representative of the touch surface. A location of the touch implement is determined relative to the touch surface using the predefined curve to which the data is fitted.

Abstract: An untethered stylus is configured to cooperate with a location sensing device that generates a drive signal. The stylus includes transceiver circuitry disposed in a housing, which is configured to receive the drive signal and transmit a stylus signal for reception by the location sensor. Energy circuitry is disposed in the housing and energized by the drive signal. A reference frequency generator, disposed in the housing and coupled to the transceiver circuitry and energy circuitry, is configured to generate a number of reference frequencies based on a source frequency of the drive signal, the reference frequencies indicative of a number of stylus states and synchronized to the source frequency of the drive signal. The transceiver circuitry is configured to mix the reference frequencies with the stylus signal.

Abstract: An untethered stylus is configured to cooperate with a location sensing device that generates a drive signal. The stylus includes transceiver circuitry disposed in a housing, which is configured to receive the drive signal and transmit a stylus signal for reception by the location sensor. Energy circuitry is disposed in the housing and energized by the drive signal. A reference frequency generator, disposed in the housing and coupled to the transceiver circuitry and energy circuitry, is configured to generate a number of reference frequencies based on a source frequency of the drive signal, the reference frequencies indicative of a number of stylus states and synchronized to the source frequency of the drive signal. The transceiver circuitry is configured to mix the reference frequencies with the stylus signal.

Abstract: An untethered stylus is configured to cooperate with a location sensing device that generates a drive signal. The stylus includes transceiver circuitry disposed in a housing, which is configured to receive the drive signal and transmit a stylus signal for reception by the location sensor. Energy circuitry is disposed in the housing and energized by the drive signal. A reference frequency generator, disposed in the housing and coupled to the transceiver circuitry and energy circuitry, is configured to generate a number of reference frequencies based on a source frequency of the drive signal, the reference frequencies indicative of a number of stylus states and synchronized to the source frequency of the drive signal. The transceiver circuitry is configured to mix the reference frequencies with the stylus signal.

Abstract: An energy transfer apparatus with a magnetic shield is configured to magnetically couple energy from a fixed location to a mobile or moveable device within a field-activated space of the energy transfer apparatus. Apparatuses include a location sensing surface and a drive coil arranged in relation to a periphery of the location sensing surface. A magnetic shield plate is disposed below the location sensing surface and the drive coil. The shield plate includes a number of radially oriented slots originating at, and distributed about, a periphery of the shield plate.

Abstract: An energy transfer apparatus with a magnetic shield is configured to magnetically couple energy from a fixed location to a mobile or moveable device within a field-activated space of the energy transfer apparatus. Apparatuses include a location sensing surface and a drive coil arranged in relation to a periphery of the location sensing surface. A magnetic shield plate is disposed below the location sensing surface and the drive coil. The shield plate includes a number of radially oriented slots originating at, and distributed about, a periphery of the shield plate.

Abstract: An energy transfer apparatus with a magnetic shield is configured to magnetically couple energy from a fixed location to a mobile or moveable device within a field-activated space of the energy transfer apparatus. Apparatuses include a location sensing surface and a drive coil arranged in relation to a periphery of the location sensing surface. A magnetic shield plate is disposed below the location sensing surface and the drive coil. The shield plate includes a number of radially oriented slots originating at, and distributed about, a periphery of the shield plate.

Abstract: Methods are provided for simulating a touch on a touch screen by applying a first signal to a first surface of the touch screen, applying a second signal to a second, opposing surface of the touch screen sensor, and changing the first signal relative to the second signal. Such methods can be used to simulate a touch to the center of the touch screen, for example. The simulated touch can be used in some embodiments to perform diagnostics and/or calibrations functions.

Abstract: An energy transfer apparatus with a magnetic shield is configured to magnetically couple energy from a fixed location to a mobile or moveable device within a field-activated space of the energy transfer apparatus. Apparatuses include a location sensing surface and a drive coil arranged in relation to a periphery of the location sensing surface. A magnetic shield plate is disposed below the location sensing surface and the drive coil. The shield plate includes a number of radially oriented slots originating at, and distributed about, a periphery of the shield plate.

Abstract: An untethered stylus is configured to cooperate with a location sensing device that generates a drive signal. The stylus includes transceiver circuitry disposed in a housing, which is configured to receive the drive signal and transmit a stylus signal for reception by the location sensor. Energy circuitry is disposed in the housing and energized by the drive signal. A reference frequency generator, disposed in the housing and coupled to the transceiver circuitry and energy circuitry, is configured to generate a number of reference frequencies based on a source frequency of the drive signal, the reference frequencies indicative of a number of stylus states and synchronized to the source frequency of the drive signal. The transceiver circuitry is configured to mix the reference frequencies with the stylus signal.

Abstract: Methods and devices for determining the location of a touch implement relative to a touch locating sensing device involve developing touch signals at a touch sensor in response to a touch implement on or near the touch surface. Data associated with the touch signals is fitted to a predefined curve. The predefined curve is preferably defined by a charged sphere near a conducting plane, the charged sphere representative of an end of the touch implement and the conducting plane representative of the touch surface. A location of the touch implement is determined relative to the touch surface using the predefined curve to which the data is fitted.

Abstract: Touch panel systems and methods are disclosed that can distinguish temporally overlapping touch inputs from single touch inputs so that valid touch position coordinates can be determined. Touch panel systems and methods of the present invention can distinguish overlapping touches by comparing signal magnitudes to specified thresholds, by comparing the rates of change of signal magnitudes or measured positions to determined parameters, by locating the proximity a calculated location to icons or other such active areas, and the like. Because touch panel systems and methods of the present invention can discriminate single touches from double touches, they can be used in multiple user applications such as multiplayer games as well as in applications that may be subject to rapidly successive or overlapping touch inputs.

Abstract: Disclosed is a touch screen calibration system and method that applies a signal to a the terminals of a touch screen and applies a calibration impedance to those terminals; the effect of the calibration impedance applied to the terminals is sensed; the X, Y position for each terminal is calculated upon application of the calibration impedance and the offset error for each terminal is calculated and applied to obtain the corrected touch position for a measured touch position; in addition the gain error may be calculated for each terminal and applied to obtain the corrected touch position.

Abstract: Touch panel systems and methods are disclosed that can distinguish temporally overlapping touch inputs from single touch inputs so that valid touch position coordinates can be determined. Touch panel systems and methods of the present invention can distinguish overlapping touches by comparing signal magnitudes to specified thresholds, by comparing the rates of change of signal magnitudes or measured positions to determined parameters, by locating the proximity a calculated location to icons or other such active areas, and the like. Because touch panel systems and methods of the present invention can discriminate single touches from double touches, they can be used in multiple user applications such as multiplayer games as well as in applications that may be subject to rapidly successive or overlapping touch inputs.