Haptic display with simultaneous sensing and actuation

A method of using a plurality of electrodes disposed on a front surface of an insulating substrate of a touch interface arranged in a pattern to simultaneously produce haptic effects on the substrate and measure finger locations relative to the substrate, the method comprising:

• providing a controller that is connect to each electrode;
• applying at least one sensing voltage pulse to each of the electrodes to measure locations of touch points,
• wherein the electronic controller reduces or eliminates a user's perception of the sensing voltage pulse by modulating at least one of a duration of the at least one sensing voltage pulse, frequency of the at least one sensing voltage pulse, and number of sensing voltage pulses;
• applying at least one actuating voltage pulse to the touch points to produce the haptic effect,
• wherein the electronic controller strengthens the haptic effect by modulating at least one of a duration of the at least one actuating voltage pulse, frequency of the at least one actuating voltage pulse, and number of actuating voltage pulses, wherein the haptic effect is more perceptible to a user than the at least one sensing voltage pulse and wherein a level of the at least one sensing voltage pulse and a level of the at least one actuating voltage pulse are substantially the same.

A touch interface having simultaneous sensing and actuation comprising:

• an insulating substrate;
• a plurality of electrodes connected to a front surface of the substrate and being arranged in a pattern;
• an electronic controller configured to connect each electrode to a sensing voltage and an actuating voltage;
• wherein the actuating voltage comprises a plurality of actuating pulses, wherein said electronic controller is configured to produce a haptic effect by applying the plurality of actuating pulses to said electrodes, wherein the plurality of actuating pulses comprises at least 50 actuating pulses, wherein each actuating pulse is at a duration of 50 microseconds or greater, and wherein each pulse is at a rate of 100 Hz or greater;
• and
• wherein the sensing voltage comprises a single sensing pulse, wherein said electronic controller configured to measure locations of touch points by applying the single sensing pulse to each electrode, wherein the single sensing pulse has a duration of 100 microseconds or less and a rate of 500 Hz or greater, and wherein a level of the sensing voltage is substantially the same as a level of the actuating voltage.