Vertical optical sectioning using a magnetically driven confocal microscanner aimed for in vivo clinical imaging

Department of Mechanical Engineering, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
Optics Express (Impact Factor: 3.49). 12/2011; 19(25):25161-72. DOI: 10.1364/OE.19.025161
Source: PubMed


This paper presents a confocal microscanner for direct vertical optical sectioning of biological samples. Confocal imaging is performed by transverse (X-axis) and axial (Z-axis) scanning of a focused laser beam using an optical fiber and a microlens respectively. The actuators are fabricated by laser micromachining techniques and are driven by electromagnetic forces. Optical and mechanical performance of the system is predicted by simulation software packages and characterized by experimental measurements. The scanner has lateral resolution of 3.87 µm and axial resolution of 10.68 µm with a field of view of 145 µm in X and 190 µm in Z directions. Confocal imaging of a polymer layer deposited on a silicon wafer and onion epidermal cells is demonstrated.

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Available from: Haishan Zeng, Jan 23, 2015
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    • "Microelectromechanical systems (MEMS) and micro-optics technologies enable the development of miniature endomicroscopes within space constraints of millimeter dimensions [3,4]. An axial scanning method has been demonstrated that translates a bulky or miniature objective lens [8–10] placed in direct contact with the tissue. However, this strategy can introduce significant image distortions [11] and disturb the biological sample during imaging [8]. "
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