Flexible fiber-laser ultrasound sensor for multiscale photoacoustic imaging

• 作者: Bai-Ou Guan Long Jin Jun Ma Yizhi Liang Xue Bai
• 来源期刊: 光电进展（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: Review
• 页码范围: 16-29
• 页数: 14页
• 语种: 英文
• DOI: 10.29026/oea.2021.200081

摘要

Photoacoustic imaging (PAl) is a noninvasive biomedical imaging technology capable of multiscale imaging of biological samples from organs down to cells.Multiscale PAl requires different ultrasound transducers that are flat or focused be-cause the current widely-used piezoelectric transducers are rigid and lack the flexibility to tune their spatial ultrasound re-sponses.Inspired by the rapidly-developing flexible photonics,we exploited the inherent flexibility and low-loss features of optical fibers to develop a flexible fiber-laser ultrasound sensor (FUS) for multiscale PAl.By simply bending the fiber laser from straight to curved geometry,the spatial ultrasound response of the FUS can be tuned for both wide-view optic-al-resolution photoacoustic microscopy at optical diffraction-limited depth (～1 mm) and photoacoustic computed tomo-graphy at optical dissipation-limited depth of several centimeters.A radio-frequency demodulation was employed to get the readout of the beat frequency variation of two orthogonal polarization modes in the FUS output,which ensures low-noise and stable ultrasound detection.Compared to traditional piezoelectrical transducers with fixed ultrasound re-sponses once manufactured,the flexible FUS provides the freedom to design multiscale PAl modalities including wear-able microscope,intravascular endoscopy,and portable tomography system,which is attractive to fundamental biologic-al/medical studies and clinical applications.