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Three-Dimensional Ultrasonic Needle Tip Tracking with a Fiber-Optic Ultrasound Receiver

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Published on: August 21, 2018

Complex amplitude encoding metalens realizing arbitrary ultrasonic needle beams.

Yu-Hang Lv¹, Xing Chen¹, Jie Yao²

¹Institute of Acoustics, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China.

|March 22, 2025

Summary

Researchers developed a novel metalens to create ultrasonic needle beams (UNB) by encoding complex amplitude. This technique enables precise control over multifocal points for advanced ultrasonic applications.

Keywords:

Complex amplitude encoding Metalens Ultrasonic needle beam

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Area of Science:

Acoustics and Optics
Materials Science

Background:

Extending depth of focus is crucial for various applications.
Advanced ultrasonic applications require diverse focal control, presenting scientific challenges.

Purpose of the Study:

To propose a method for creating ultrasonic needle beams (UNB) using complex amplitude encoding.
To demonstrate the capability of a designed metalens for generating single or twin UNBs.

Main Methods:

Utilizing super-units to encode two phase distributions into a single metalens.
Implementing complex-amplitude modulation for multifocal point generation.
Optimizing metalens performance by adjusting super-unit parameters.

Main Results:

Simulations and experiments confirmed the efficient production of single or twin UNBs.
The designed metalens successfully achieved complex-amplitude modulation.
Metalens performance was enhanced through super-unit parameter adjustments.

Conclusions:

The proposed complex amplitude encoding with super-units offers an effective approach for generating ultrasonic needle beams.
This technology holds significant potential for biomedical treatments, imaging, communication, and nondestructive detection.