ULTRASONIC FLUID CLEARING SYSTEMS

A system comprises a plate () and one or more transducers () coupled to the plate (). Each of the one or more transducers () is operable to generate ultrasonic waves which propagate through the plate () in a propagation direction (), for ultrasonically clearing droplets () of fluid from the plate (). The plate () comprises one or more structures disposed in the path of ultrasonic waves and configured to control the propagation of ultrasonic waves in the plate () to achieve a predetermined amount of ultrasonic wave energy propagating in a direction opposite to the propagation direction (). The value of one or more parameters of the shape of each of the one or more structures is predetermined to achieve a predetermined effect on ultrasonic waves incident on the structure.