Mobley, JoelCullum, BrianVo-Dinh, Tuan2024-09-042024-09-042001-06-04Mobley, Joel, Brian M. Cullum, and Tuan Vo-Dinh. “Ultrasonic Diffraction in the Design of Photoacoustic Probes.” In Biomedical Diagnostic, Guidance, and Surgical-Assist Systems III, 4254. (June 4, 2001): 151–63. https://doi.org/10.1117/12.427956.https://doi.org/10.1117/12.427956http://hdl.handle.net/11603/36048BiOS 2001 The International Symposium on Biomedical Optics, 2001, San Jose, CA, United StatesIn this work, we examine the role of diffraction in the design of ring-shaped ultrasonic receivers for photoacoustic probes. The sensitivity patterns of ultrasonic receiving rings are calculated at 1 MHz using the angular spectrum technique. Three separate series of simulations are considered: flat ring with a fixed outer diameter and a variable inner diameter, flat ring with a fixed inner diameter and variable outer diameter, and a spherically focused ring with a variable inner diameter. From these results the focal zone characteristic and sensitivities are calculated. For the planar rings, we find that the spatial sensitivity varies markedly with ring width but the overall sensitivities are comparable. For the focused (spherically curved) rings, the focal distances and beam volumes were similar while the sensitivity grew with ring thickness.13 pagesen-USThis work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.Public Domainhttps://creativecommons.org/publicdomain/mark/1.0/Text