Assessing Transducer Parameters for Accurate Medium Sound Speed Estimation and Image Reconstruction

Area of Science:

• Ultrasound physics
• Medical imaging technology
• Acoustic characterization

Background:

• Transducer lens properties significantly impact ultrasound image reconstruction quality.
• Accurate characterization of lens sound speed and thickness is crucial but often unknown in research.
• Internal reflections within the lens are key to understanding its acoustic behavior.

Purpose of the Study:

• To develop a simple, nondestructive method for characterizing ultrasound transducer lens sound speed, thickness, and waveform time to peak.
• To validate the method's effectiveness across different transducer frequencies (2.5, 7.5, and 15 MHz).
• To demonstrate improved ultrasound image reconstruction using the characterized parameters.

Main Methods:

• An element-by-element transmission sequence was used to record internal lens reflections.
• Characterized parameters were validated using an autofocusing approach in water.
• A two-layer ray tracing model was combined with the estimated parameters for image reconstruction.

Main Results:

• The method accurately estimated lens sound speed, thickness, and waveform time to peak for multiple transducers.
• Autofocusing validation confirmed the retrieved acoustic parameters.
• Image reconstruction using the new method showed improved medium sound speed estimation, spatial resolution, and contrast.

Conclusions:

• The proposed method provides accurate estimation of essential transducer lens parameters and waveform characteristics.
• This technique is simple, robust, and leads to enhanced ultrasound image quality.
• Accurate lens characterization is vital for optimizing ultrasound image reconstruction and diagnostic capabilities.