A Novel Two-element Scanner for High-frequency Ultrasound Imaging

This paper presents a novel hybrid two-element scanner (HyTES) for high-frequency ultrasound imaging. The proposed scanner utilizes a combination of a focused and an unfocused high-frequency transducer elements to improve the quality of reconstructed image. An experimental prototype of the proposed scanner is made to serve as proof-of-concept. The scan data obtained from the proposed scheme is beamformed using the recently proposed non-linear beamformer of F-DewMAS, and the results are compared with state-of-the-art monostatic Delay-And-Sum (DAS) and recently proposed Virtual -source-in-front of the transducer with DAS (VS-DAS) beamforming that uses data from only the focused element. As a minor innovation, Virtual Source beamforming is adapted to Delay-Multiply-And-Sum to develop VS-DMAS, which is utilized to reconstruct two element data and the results are compared with other methods. The proposed scanning technology with F-DewMAS beamforming is able improve the image quality by more than 52 % and 63 % in terms of resolution and by more than 44 % and 57 % in terms of CNR and GCNR compared to the recent VS-DAS and monostatic DAS, respectively. Further, the newly proposed VS-DMAS was able to improve resolution and contrast compared to existing methods. However, the performance in terms of the image quality metrics were not as much as obtained with the proposed HyTES. The proposed technology has the potential to improve the image quality without the need for an array, manufacturing of which is a challenge at High-frequencies.