{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T14:37:29Z","timestamp":1776955049962,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,5,15]],"date-time":"2022-05-15T00:00:00Z","timestamp":1652572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of SMEs and Startups (MSS)","award":["R&D, S3089764"],"award-info":[{"award-number":["R&D, S3089764"]}]},{"name":"Korea Institute for Advancement of Technology (KIAT)","award":["R&D, S3089764"],"award-info":[{"award-number":["R&D, S3089764"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, we report an advanced fabrication technique to develop a miniature focused needle transducer. Two different types of high-frequency (100 MHz) transducers were fabricated using the lead magnesium niobate-lead titanate (PMN-0.3PT) and lithium niobate (LiNbO3) single crystals. In order to enhance the transducer\u2019s performance, a unique mass\u2013spring matching layer technique was adopted, in which gold and parylene play the roles of the mass layer and spring layer, respectively. The PMN-0.3PT transducer had a 103 MHz center frequency with a \u22126 dB bandwidth of 52%, and a signal-to-noise ratio (SNR) of 42 dB. The center frequency, \u22126 dB bandwidth, and SNR of the LiNbO3 transducer were 105 MHz, 66%, and 44 dB, respectively. In order to compare and evaluate the transducers\u2019 performances, an ultrasonic biomicroscopy (UBM) imaging on the fish eye was performed. The results showed that the LiNbO3 transducer had a better contrast resolution compared to the PMN-0.3PT transducer. The fabricated transducer showed an excellent performance with high-resolution corneal epithelium imaging of the experimental fish eye. These interesting findings are useful for the future biomedical implementation of the fabricated transducers in the field of high-resolution ultrasound imaging and diagnosis purpose.<\/jats:p>","DOI":"10.3390\/s22103763","type":"journal-article","created":{"date-parts":[[2022,5,15]],"date-time":"2022-05-15T09:48:22Z","timestamp":1652608102000},"page":"3763","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Design and Micro-Fabrication of Focused High-Frequency Needle Transducers for Medical Imaging"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5654-7214","authenticated-orcid":false,"given":"Thanh Phuoc","family":"Nguyen","sequence":"first","affiliation":[{"name":"Department of Mechatronics, Cao Thang Technical College, Ho Chi Minh City 700000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jaeyeop","family":"Choi","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4913-438X","authenticated-orcid":false,"given":"Van Tu","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sudip","family":"Mondal","sequence":"additional","affiliation":[{"name":"New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ngoc Thang","family":"Bui","sequence":"additional","affiliation":[{"name":"Institute of Engineering, HUTECH University, Ho Chi Minh City 700000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4011-8826","authenticated-orcid":false,"given":"Dinh Dat","family":"Vu","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sumin","family":"Park","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5837-0958","authenticated-orcid":false,"given":"Junghwan","family":"Oh","sequence":"additional","affiliation":[{"name":"Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea"},{"name":"New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Korea"},{"name":"Ohlabs Corporation, Busan 48513, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Liu, Y., Li, D., and Yuan, Z. 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