An encapsulated optical microsphere sensor for ultrasound detection and photoacoustic imaging

• 作者: Jialve Sun Jia-Wei Meng Shui-Jing Tang Changhui Li
• 来源期刊: 中国科学：物理学 力学 天文学（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: Article
• 页码范围: 44-49
• 页数: 6页
• 语种: 英文

摘要

Optical whispering-gallery microresonators have attracted considerable interest for ultrasensitive ultrasound detection and photoacoustic imaging because of the combination of high quality factors and small cavity sizes.In the last decade,ultrasonic sensors with on-chip microcavities have been extensively developed;however,they are unsuitable for the near-field photo-acoustic microscopy of micro/nanoscale objects in complex biological environments and endoscopic imaging.In this work,we developed ultrasonic sensors using two types of encapsulated microsphere resonators with different cavity materials.A noise equivalent pressure of as low as 160 Pa at 20 MHz was achieved with the acoustic response up to 70 MHz at-6 dB.Furthermore,the microsensor was used for photoacoustic microscopy in which we successfully performed 3D imaging of hairs and leaf veins.The microsphere ultrasonic sensor has considerable potential as a probe-type ultrasonic detector for near-field photoacoustic microscopy of micro/nanoscale objects such as subcellular structures and high-resolution endoscopic photoacoustic imaging with its high sensitivity and wide bandwidth.