Miniaturized all-optical photoacoustic microscopy based on microelectromechanical systems mirror scanning

Optics Letters (Impact Factor: 3.29). 10/2012; 37(20):4263-5. DOI: 10.1364/OL.37.004263
Source: PubMed


Achieving photoacoustic microscopic imaging through a miniaturized scanning head is a crucial step toward high-resolution photoacoustic endoscopy. In this work, we have developed a miniaturized probe head using a microelectromechanical systems (MEMS) based mirror for raster scan of the laser beam and our newly developed super broad bandwidth microring resonator based ultrasound detector for photoacoustic signal detection. Through this all-optical design, which offers unique advantages for endoscopic applications, this system is capable of three-dimensional (3D) imaging with high resolution of 17.5 μm in lateral direction and 20 μm in axial direction at a distance of 3.7 mm. After the performance of this system was validated through the experiments on printed grids and a resolution test target, microscopic imaging of the 3D microvasculatures in canine bladders was also conducted successfully, demonstrating the potential of novel photoacoustic endoscopic in future clinical management of bladder cancer.

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Available from: Sung-Liang Chen, May 01, 2014
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    • "form with a raster scan of the laser beam performed by a microelectro-mechanical-systems (MEMS) mirror, which is used to meet the requirement of system miniaturization [84]. The system is capable of 3D imaging with high resolutions of 17.5 μm in lateral direction and 20 μm in axial direction. "
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    • "The maximum angular deflections are AE68 and AE98, resulting in a large field-of-view of 1.29 mm  1.95 mm considering the 6.16 mm focal length of the objective lens. More details of the MEMS mirror used in this work can be found in our previous work [27]. Due to the 50 Hz limit of the MEMS driver board, a 2D raster scan of 256  256 steps takes almost half an hour, which also includes the data transfer time. "
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