A method for distribution control of aerial ultrasound radiation pressure for remote vibrotactile display

We propose a calculation method for phase and amplitude of ultrasound transducers in arrays, which are supposed to generate proper spatial distribution of radiation pressure on users´ skin corresponding to vibrotactile sensation conveyed to users. The phased array technique has been applied for ultrasound transducer array and converged energy in a focus of magnified amplitude in the air has been successfully generated as well as vibrotactile stimulation in a point. In this paper we expand that phasing scheme for a single focus to arbitrary three-dimensional distribution amplitude with transducers located in three-dimensional disposition. We verify the validity of our method with numerical experiments.