Multi-focused acoustic holograms by 3D printing

The focused ultrasound (FUS) systems are widely used due to their ability to generate a tight and intense focal region from a distributed source for the non-invasive and safely detection. However, these devices usually require elaborate arrays of a rather complex and cumbersome set of transducers. Holographic techniques are fundamental to applications such as volumetric displays and tweezers. The monolithic acoustic holograms can reconstruct diffraction-limited acoustic pressure fields and arbitrary ultrasound beams.