cMUTs and electronics for 2D and 3D imaging: monolithic integration, in-handle chip sets and system implications

Capacitive microfabricated ultrasound transducers (cMUTs) have been shown to be practical for medical imaging. Breakthrough performance requires combining these MEMS transducers with electronics. This paper explores synergies between cMUTs and electronics for 2D and 3D imaging. For example, low-noise receive signal conditioning improves tissue penetration, while transmitters capable of arbitrary waveforms minimize clutter. Bias control circuitry can create simple multi-row arrays for improved 2D contrast resolution. It also can enable 3D scanning with less complexity than current alternatives. Matrix transducer elements for 3D present challenges due to their high impedance, number and density. Monolithically integrated cMUTs can offer unique solutions to these problems, enabling isotropic 3D imaging from fully sampled arrays.

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