Annular Shear Wave Transducer for Extended Propagation

The transducer array is divided into multiple independently controllable elements that can be activated in specific patterns. By segmenting the excitation source and controlling individual elements or groups of elements, the system creates multiple shear wave sources that propagate toward a common focal region, enabling constructive interference and extended propagation distances without amplitude loss.

Multiple shear waves generated from different transducer elements are combined through constructive interference at a predetermined focal region. The waves from different elements merge in phase, creating a concentrated shear wave field that maintains amplitude over longer propagation distances, effectively combining the energy from multiple sources.

The system pre-calculates and stores the relationship between transducer element activation patterns and resulting shear wave arrival times at various spatial locations. By establishing these timing relationships in advance through modeling or calibration, the system eliminates the need for complex real-time signal processing to determine arrival times, reducing computational overhead during actual measurements.

The patent replaces complex signal processing algorithms with a simplified timing-based measurement approach. Instead of analyzing waveforms to estimate arrival times, the system uses predetermined timing information based on the known geometry and propagation characteristics, substituting mechanical/acoustic principles for computational complexity.