Tunable liquid-based lenses for ultrasonic beamforming

Quasi-planar stepped lenses (QSL’s) based on phasing have proven to perform closely to conventional refractive lenses for the generation of both focused and limited diffraction beams. However, since QSLs are passive and made from solid materials, each must be designed with a specific frequency and beam type in mind. In this presentation, we report on a tunable lens with a planar aperture that employs liquid channels to perform phase-based beamforming. The desired phase patterns are produced using specific speed-of-sound profiles and can be flexibly configured for a range of frequencies and beam types without modification. In this talk, we report on the results of both experimental and numerical results for this class of lenses and discuss their potential applications.