*Article* **3D Photoacoustic Tomography System Based on Full-View Illumination and Ultrasound Detection**

#### **Mingjian Sun 1,2,\*, Depeng Hu 1, Wenxue Zhou 1, Yang Liu 2, Yawei Qu 2 and Liyong Ma 1**


Received: 25 March 2019; Accepted: 6 May 2019; Published: 9 May 2019

**Abstract:** A 3D photoacoustic computed tomography (3D-PACT) system based on full-view illumination and ultrasound detection was developed and applied to 3D photoacoustic imaging of several phantoms. The system utilized an optics cage design to achieve full-view uniform laser illumination and completed 3D scanning with the rotation of a dual-element transducer (5 MHz) and the vertical motion of imaging target, which obtains the best solution in the mutual restriction relation between cost and performance. The 3D-PACT system exhibits a spatial resolution on the order of 300 μm, and the imaging area can be up to 52 mm in diameter. The transducers used in the system provides tomography imaging with large fields of view. In addition, the coplanar uniform illumination and acoustic detection configuration based on a quartz bowl greatly enhances the e fficiency of laser illumination and signal detection, making it available for use on samples with irregular surfaces. Performance testing and 3D photoacoustic experiments on various phantoms verify that the system can perform 3D photoacoustic imaging on targets with complex surfaces or large sizes. In future, e fforts will be made to achieve full-body 3D tomography of small animals and a multimodal 3D imaging system.

**Keywords:** 3D photoacoustic tomography; full-view illumination and ultrasound detection; photoacoustic coplanar; quartz bowl
