title: Delay-multiply-and-sum-based synthetic aperture focusing in photoacoustic microscopy.
abstract: We propose an improved version of a synthetic aperture focusing technique (SAFT) based on a delay-multiply-and-sum algorithm for acoustic-resolution photoacoustic microscopy (AR-PAM). In this method, the photoacoustic (PA) signals from multiple scan-lines are combinatorially coupled, multiplied, and then summed. This process can be considered a correlation operation of the PA signals in each scan-line, so the spatial coherent information between the PA signals can be efficiently extracted. By applying this method in conventional AR-PAM, lateral resolution and signal-to-noise ratio in out-of-focus regions are much improved compared with those estimated from the previously developed SAFT, respectively, thereby achieving the extension of the imaging focal region. Our phantom and in vivo imaging experiments prove the validity of our proposed method.
authors.affiliation: Pohang University of Science and Technology, Departments of Electrical Engineering and Creative IT Engineering, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, Republic of Korea.
authors.forename: Jongin
authors.initials: J
authors.lastname: Park
authors.affiliation: Pohang University of Science and Technology, Departments of Electrical Engineering and Creative IT Engineering, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, Republic of Korea.
authors.forename: Seungwan
authors.initials: S
authors.lastname: Jeon
authors.affiliation: Qufu Normal University, School of Information Science and Technology, 80 Yantai Road North, Rizhao 276826, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Meng
authors.affiliation: Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Institute of Biomedical and Health, 1068 Xueyuan Avenue, University Town of Shenzhen, Shenzhen 518055, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Song
authors.affiliation: Pohang University of Science and Technology, Departments of Electrical Engineering and Creative IT Engineering, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, Republic of Korea.
authors.forename: Jin S
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Pohang University of Science and Technology, Departments of Electrical Engineering and Creative IT Engineering, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784, Republic of Korea.
authors.forename: Chulhong
authors.initials: C
authors.lastname: Kim
mesh_terms: D000005:Abdomen / Q000000981:diagnostic imaging; D000465:Algorithms; D000818:Animals; D004867:Equipment Design; D006614:Hindlimb / Q000000981:diagnostic imaging; D051379:Mice; D033401:Microscopy, Acoustic / Q000295:instrumentation / Q000379:methods*; D061088:Photoacoustic Techniques / Q000295:instrumentation / Q000379:methods*; D012815:Signal Processing, Computer-Assisted