Ultrasound transducers emit a pulse that hits a user's hand and then measure how long it takes for the echo to come back to move an object on display. This ultra-low-power, ultra-small sensor from Chirp Microsystems can run for 30 hours on a charge and can be easily embedded into wearables and movable devices. The sensor has a range of up to a meter high and a little less to the side, making it ideal for small spaces.
Chirp sensor: An ISSCC attendee demonstrates the ultrasonic gesture recognition sensor on a flight game.
(Source: EE Times/Jessica Lipsky)