TY - GEN
T1 - Design considerations for ultrasound detectors in photoacoustic breast imaging
AU - Xia, Wenfeng
AU - Piras, Daniele
AU - Singh, Mithun K.A.
AU - Van Hespen, Johan C.G.
AU - Van Veldhoven, Spiridon
AU - Prins, Christian
AU - Van Leeuwen, Ton G.
AU - Steenbergen, Wiendelft
AU - Manohar, Srirang
PY - 2013
Y1 - 2013
N2 - The ultrasound detector is the heart of a photoacoustic imaging system. In photoacoustic imaging of the breast there is a requirement to detect tumors located a few centimeters deep in tissue, where the light is heavily attenuated. Thus a sensitive ultrasound transducer is of crucial importance. As the frequency content of photoacoustic waves are inversely proportional to the dimensions of the absorbing structures, and in tissue can range from hundreds of kHz to tens of MHz, a broadband ultrasound transducer is required centered on an optimum frequency. A single element piezoelectric transducer structurally consists of the active piezoelectric material, front- and back-matching layers and a backing layer. To have both high sensitivity and broad bandwidth, the materials, their acoustic characteristics and their dimensions should be carefully chosen. In this paper, we present design considerations of an ultrasound transducer for imaging the breast such as the detector sensitivity and frequency response, which guides the selection of active material, matching layers and their geometries. We iterate between simulation of detector performance and experimental characterization of functional models to arrive at an optimized implementation. For computer simulation, we use 1D KLM and 3D finite-element based models. The optimized detector has a large-aperture possessing a center frequency of 1 MHz with fractional bandwidth of more than 80%. The measured minimum detectable pressure is 0.5 Pa, which is two orders of magnitude lower than the detector used in the Twente photoacoustic mammoscope.
AB - The ultrasound detector is the heart of a photoacoustic imaging system. In photoacoustic imaging of the breast there is a requirement to detect tumors located a few centimeters deep in tissue, where the light is heavily attenuated. Thus a sensitive ultrasound transducer is of crucial importance. As the frequency content of photoacoustic waves are inversely proportional to the dimensions of the absorbing structures, and in tissue can range from hundreds of kHz to tens of MHz, a broadband ultrasound transducer is required centered on an optimum frequency. A single element piezoelectric transducer structurally consists of the active piezoelectric material, front- and back-matching layers and a backing layer. To have both high sensitivity and broad bandwidth, the materials, their acoustic characteristics and their dimensions should be carefully chosen. In this paper, we present design considerations of an ultrasound transducer for imaging the breast such as the detector sensitivity and frequency response, which guides the selection of active material, matching layers and their geometries. We iterate between simulation of detector performance and experimental characterization of functional models to arrive at an optimized implementation. For computer simulation, we use 1D KLM and 3D finite-element based models. The optimized detector has a large-aperture possessing a center frequency of 1 MHz with fractional bandwidth of more than 80%. The measured minimum detectable pressure is 0.5 Pa, which is two orders of magnitude lower than the detector used in the Twente photoacoustic mammoscope.
KW - breast imaging
KW - finite-element method
KW - photoacoustic
KW - ultrasound transducer
UR - http://www.scopus.com/inward/record.url?scp=84878092666&partnerID=8YFLogxK
U2 - https://doi.org/10.1117/12.2004329
DO - https://doi.org/10.1117/12.2004329
M3 - Conference contribution
SN - 9780819493507
T3 - Progress in Biomedical Optics and Imaging - Proceedings of SPIE
BT - Photons Plus Ultrasound
T2 - Photons Plus Ultrasound: Imaging and Sensing 2013
Y2 - 3 February 2013 through 5 February 2013
ER -