Acoustic-resolution photoacoustic microscopy based on an optically transparent focused transducer with a high numerical aperture

This Letter reports acoustic-resolution-photoacoustic microscopy (AR-PAM) based on a new optically transparent focused polyvinylidene fluoride (PVDF) transducer with a high acoustic numerical aperture (NA) of 0.64. Owing to the improved fabrication process, the new transducer has a much higher NA (0.64) than the previously reported low-NA transducer ($NA=0.23$). The acoustic center frequency and (pulse-echo) bandwidth are also increased to 36 and 44 MHz, respectively, which provides a 38 µm acoustic focal spot size and 210 µm acoustic depth of focus. For demonstration, AR-PAM was conducted on a twisted wire target in water and chicken breast tissue, andin vivoon a mouse tail. The imaging results show that high acoustic resolution and sensitivity can be achieved with a simple and compact setup to resolve the target at different depths. Such capabilities can be useful for the development of new AR-PAM systems for handheld, wearable, and even endoscopic imaging applications.

Authors:
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Publication Date:
NSF-PAR ID:
10258376
Journal Name:
Optics Letters
Volume:
46
Issue:
13
Page Range or eLocation-ID:
Article No. 3280
ISSN:
0146-9592; OPLEDP
Publisher:
Optical Society of America
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