Various approaches for calibrating the geometry of an ultrasound transducer having multiple transducer elements include providing an acoustic reflector spanning an area traversing by multiple beam paths of ultrasound waves transmitted from all (or at least some) transducer elements to a focal zone; causing the transducer elements to transmit the ultrasound waves to the focal zone; measuring reflections of the ultrasound waves off the acoustic reflector; and based at least in part on the measured reflections, determining optimal geometric parameters associated with the transducer elements.