Improved Depth-of-Field Photoacoustic Microscopy with a Multifocal Point Transducer for Biomedical Imaging

Sensors (Basel). 2020 Apr 3;20(7):2020. doi: 10.3390/s20072020.

Abstract

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.

Keywords: biomedical imaging; multifocal point transducer; photoacoustic imaging; photoacoustic microscopy; ultrasound.

MeSH terms

  • Animals
  • Chickens
  • Equipment Design
  • Hemoglobins / analysis
  • Image Processing, Computer-Assisted
  • Meat / analysis
  • Microscopy / instrumentation
  • Microscopy / methods*
  • Photoacoustic Techniques*
  • Transducers*
  • Ultrasonography

Substances

  • Hemoglobins