3m Innovative Properties Company

Richard A Peterson, Jr

Gordon F Taylor

Bruce A Lessard

Rodrigo S Gomes

Bernard O Geaghan

Robert S Moshrefzadeh

Craig A Cordeiro

Thomas J Rebeschi

Stephen C Schulz

Edward S Hagermoser

Karl P Hauck

Rachael P Marino

James J Hart

Paul M Hatin

Touch sensing circuit arrangements include a touch sensor and a controller board. The touch sensor includes one or more sensing elements to generate touch-related signals responsive to a touch input to the sensor, and a memory device storing computer-executable firmware instructions for determining touch positions based on the touch-related signals. The controller board includes query logic executable by the controller board to cause the controller board to query for the computer-executable firmware instructions stored on the memory device of the touch sensor, and a processor circuit to determine touch positions by executing the firmware instructions loaded onto the generic controller board in response to the query.

Touch systems and methods utilizing customized sensors and genericized controllers

A touch-sensitive device includes a touch panel, drive unit, and measurement unit. A touch applied to a given node of the panel changes a capacitive coupling between a given drive and sense electrode of the touch panel. The drive unit delivers first and second drive signals, having different first and second frequencies, to first and second drive electrodes respectively at the same or overlapping times. The measurement unit receives a first response signal from a sense electrode, and analyzes the signal using maximum likelihood estimation to determine the coupling capacitance between the first drive electrode and the sense electrode, and between the second drive electrode and the sense electrode. More drive electrodes, including in some cases all the drive electrodes, can be driven with unique drive frequencies, and more sense electrodes, including in some cases all the sense electrodes, can be sensed by the measurement unit.

Multi-touch touch device with multiple drive frequencies and maximum likelihood estimation

The present invention provides systems and methods for detecting stray capacitance in capacitive touch sensors. The existence of stray capacitance can lead to errors in touch detection and touch position determination. Such errors can be avoided or corrected when the stray capacitance is detected. Detecting stray capacitance includes analyzing signals for features characteristic of stray capacitance noise events. Such features can include spatial features such as the location of a test touch position determined from signals caused by stray capacitance, as well as temporal features such as the rate of change of the detected signals.

Detection of and compensation for stray capacitance in capacitive touch sensors

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.

Touch panel system and method for distinguishing multiple touch inputs

Bending wave vibrations propagating in a substrate of a touch input device are sensed. Provision is made for discriminating between sensed vibrations propagating in the substrate indicative of an intended touch and sensed vibrations propagating in the substrate indicative of an unintended touch. In response to the sensed vibrations propagating in the substrate indicative of the intended touch, a wake-up signal is generated. The wake-up signal is communicated to a control system of the touch input device for transitioning the control system from a sleep state to an operational state.

Wake-on-touch for vibration sensing touch input devices

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Chelmsford, MA, United States of America

Richard A Peterson, Jr