In this study, a photoacoustic microscopy (PAM) system based on a multifocal point (MFP) transducer was fabricated to produce a large depth-of-field tissue image. The customized MFP transducer has seven focal points, distributed along with the transducer's axis, fabricated by separate spherically-focused surfaces. These surfaces generate distinct focal zones that are overlapped to extend the depth-of-field. This design allows extending the focal zone of 10 mm for the 11 MHz MFP transducer, which is a great improvement over the 0.48 mm focal zone of the 11 MHz single focal point (SFP) transducer. The PAM image penetration depths of a chicken-hemoglobin phantom using SFP and MFP transducers were measured as 5 mm and 8 mm, respectively. The significant increase in the PAM image-based penetration depth of the chicken-hemoglobin phantom was a result of using the customized MFP transducer.

中文翻译：

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改进的景深光声显微镜技术，用于生物医学成像的多焦点传感器。

在这项研究中，制造基于多焦点（MFP）换能器的光声显微镜（PAM）系统，以产生大景深的组织图像。定制的MFP换能器具有七个焦点，这些焦点与换能器的轴一起分布，由单独的球形聚焦表面构成。这些表面生成不同的聚焦区，这些聚焦区重叠以扩展景深。此设计允许将11 MHz MFP换能器的焦距扩展到10 mm，这与11 MHz单焦点（SFP）换能器的0.48 mm焦距相比有很大的改进。使用SFP和MFP换能器测量的鸡血红蛋白体模的PAM图像穿透深度分别为5 mm和8 mm。