Biomedical Microdevices

, 10:653 | Cite as

Handheld subcellular-resolution single-fiber confocal microscope using high-reflectivity two-axis vertical combdrive silicon microscanner



We introduce a handheld single-fiber laser-scanning confocal microscope, incorporating a high-reflectivity two-axis silicon vertical combdrive microscanner, aimed at in vivo early detection of epithelial precancers. The approach adopted is motivated by need for a portable, economical, biopsy-free, early precancer screening technology in low-infrastructure environments. Our microelectromechanical system (MEMS) based handheld probe integrates the microscanners with miniature objective lens system and flexible electrical routing in a forward-imaging configuration, with 4.8 mm distal probe tip outer diameter for unrestricted imaging access in biological sites such as the oral cavity and cervix. Reflectance confocal videos of a USAF 1951 resolution target and biological samples were obtained over 200 μm × 110 μm field of view, with 0.80 and 9.55 μm lateral and axial resolution, at 3.5–5.0 frames per second. With improvements to objective numerical aperture, our probe can enable precise evaluation of nuclear size, density, nucleus-to-cytoplasm ratio and cell density, which are important visual identifiers of epithelial precancers.


Microelectromechanical systems Two-axis microscanner Confocal microscopy Handheld probe Biomedical diagnostics Subcellular imaging 


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Karthik Kumar
    • 1
  • Kazunori Hoshino
    • 2
  • Xiaojing Zhang
    • 2
  1. 1.Department of Electrical and Computer EngineeringUniversity of Texas at AustinAustinUSA
  2. 2.Department of Biomedical EngineeringUniversity of Texas at AustinAustinUSA

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