Capacitive micromachined ultrasonic transducer (CMUT) multi-touch and slider detection

The invention relates to capacitive micromachined ultrasonic transducer (CMUT) multi-touch and slider detection. An ultrasonic touch sensor includes a touch structure having a touch surface having a plurality of sensitive areas, a pixel array of capacitive ultrasonic transducers, and a sensor circuit. Each pixel includes a respective ultrasonic transmitter and a respective ultrasonic receiver, and is configured to monitor a touch at a respective first sensitive area and at a respective second sensitive area. Further, each pixel is configured to generate a measurement signal representative of a first respective ultrasonic reflected wave reflected by the touch interface at a respective first sensitive area, or a second respective ultrasonic reflected wave reflected by the touch interface at a respective second sensitive area. The sensor circuitry is configured to determine whether a measurement signal of a respective pixel corresponds to a respective first sensitive area or a respective second sensitive area as