Miniature photoacoustic imaging probe using MEMS scanning micromirror

This paper presents the design and characterization of an electrothermally actuated high-fill-factor tip-tilt-piston (TTP) micromirror and its application to three-dimensional (3D) photoacoustic imaging (PAI). The micromirror chip is 2mm × 2mm. It has large scan range (>25°) at low driving voltage (∼4V) and can perform fast raster scanning. A miniature PAI probe with a diameter of 11.5 mm has been developed. The 3D images of in vivo human blood vessels are successfully obtained using this MEMS-based PAI system.