title: Polymer microring resonators for high-sensitivity and wideband photoacoustic imaging.
abstract: Polymer microring resonators have been exploited for high-sensitivity and wideband photoacoustic imaging. To demonstrate high-sensitivity ultrasound detection, highfrequency photoacoustic imaging of a 49-microm-diameter black bead at an imaging depth of 5 mm was imaged photoacoustically using a synthetic 2-D array with 249 elements and a low laser fluence of 0.35 mJ/cm(2). A bandpass filter with a center frequency of 28 MHz and a bandwidth of 16 MHz was applied to all element data but without signal averaging, and a signal-to-noise ratio of 16.4 dB was obtained. A wideband detector response is essential for imaging reconstruction of multiscale objects, e.g., various sizes of tissues, by using a range of characteristic acoustic wavelengths. A simulation of photoacoustic tomography of beads shows that objects with their boundaries characteristic of high spatial frequencies and the inner structure primarily of low spatial frequency components can be faithfully reconstructed using such a detector. Photoacoustic tomography experiments of 49- and 301-microm-diameter beads were presented. A high resolution of 12.5 microm was obtained. The boundary of a 301-microm bead was imaged clearly. The results demonstrated that the high sensitivity and broadband response of polymer microring resonators have potential for high resolution and high-fidelity photoacoustic imaging.
authors: Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, USA.
authors: Sung-Liang
authors: SL
authors: Chen
authors: Sheng-Wen
authors: SW
authors: Huang
authors: Tao
authors: T
authors: Ling
authors: Shai
authors: S
authors: Ashkenazi
authors: L Jay
authors: LJ
authors: Guo
mesh_terms: D017076:Computer-Aided Design; D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers; D014732:Vibration
chemical_list: D011108:Polymers