title: Low-noise small-size microring ultrasonic detectors for high-resolution photoacoustic imaging.
abstract: Small size polymer microring resonators have been exploited for photoacoustic (PA) imaging. To demonstrate the advantages of the wide acceptance angle of ultrasound detection of small size microrings, photoacoustic tomography (PAT), and delay-and-sum beamforming PA imaging was conducted. In PAT, we compared the imaging quality using different sizes of detectors with similar noise-equivalent pressures and the same wideband response: 500 μm hydrophone and 100, 60, and 40 μm microrings. The results show significantly improved imaging contrast and high resolution over the whole imaging region using smaller size detectors. The uniform high resolution in PAT imaging using 40 μm microrings indicates the potential to resolve microvasculature over a large imaging region. The improved lateral resolution of two-dimensional and three-dimensional delay-and-sum beamforming PA imaging using a synthetic array demonstrate another advantageous application of small microrings. The small microrings can also be applied to other ultrasound-related imaging applications.
authors.affiliation: Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109, USA.
authors.forename: Sung-Liang
authors.initials: SL
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Ling
authors.forename: L Jay
authors.initials: LJ
authors.lastname: Guo
mesh_terms: D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D008904:Miniaturization; D019047:Phantoms, Imaging; D061088:Photoacoustic Techniques / Q000295:instrumentation*; D012680:Sensitivity and Specificity; D014159:Transducers