A triple-frequency transducer for endoscopic imaging: Simulation design and experimental verification

Abstract

In endoscopic ultrasound imaging, it is still challenging to acquire images with high resolution and deep imaging depth at the same time, this contradiction limits the performance of the endoscopic ultrasonic imaging system. Multi-frequency imaging and corresponding image fusion technique have the potential to reduce this contradiction. In this work, a triangle-structure triple-frequency transducer that can work at three different frequencies is presented, its outer diameter is less than 1.5mm. Static and transient models are built to assist its design. Simulation results and sound field measurement results suggest that the three different frequency elements have excellent directivity, and the acoustic field interference between elements is small. Pulse-echo results show that the center frequencies of the elements are 13.17MHz, 20.3MHz, and 30.85MHz, respectively. The ultrasound imaging results of phantom prove that the triple-frequency fusing image is better than single-frequency imaging, and the fused image can maintain the imaging depth and image resolution at the same time. The results certify the feasibility of triple-Frequency transducer in endoscopic imaging and show great potential in the diagnosis of gastrointestinal diseases.