[Problem]To correctly heat a target with simpler device configuration and user operations than in the prior art.[Solution]Disclosed is an ultrasonic oscillator that heats a target using ultrasonic waves. The ultrasonic oscillator includes: a plurality of ultrasonic oscillation elements that oscillates the ultrasonic waves a retention portion that retains the plurality of ultrasonic oscillation elements in a state where the ultrasonic oscillation elements are arranged along a concave thereof opposing the heating target and a controller that controls the ultrasonic oscillation elements so as to oscillate the ultrasonic waves.
