Ultrasound touch detection and related apparatuses and methods

A smartphone device comprising:

• a housing;
• an ultrasonic transducer device located within the housing and structured to transmit ultrasonic waves and to receive reflected waves of the ultrasonic waves, wherein the ultrasound transducer device comprises an ultrasound-on-a-chip device;
• a memory device located within the housing;
• and
• processing circuitry located within the housing and operatively connected to the ultrasonic transducer device and the memory device, wherein the processing circuitry is programmed to perform a touch-detection routine to:
• control the ultrasonic transducer device to emit a ping ultrasonic wave,
• process reflection data obtained from the ultrasonic transducer device, the reflection data corresponding to at least one reflected wave resulting from the ping ultrasonic wave, and
• activate a predetermined smartphone function if the reflection data is recognized to correspond to a pattern stored in the memory device.

A smartphone device having a sleep mode and active mode, the smartphone device comprising:

• a housing having an interior and an exterior;
• a first array of ultrasonic transducers disposed in the interior of the housing;
• and
• processing circuitry disposed in the interior of the housing and configured to control the first array of ultrasonic transducers to detect a touch on the exterior of the housing and to switch between the sleep mode and active mode in response to detecting the touch.