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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 16, Iss. 8 — Apr. 14, 2008
  • pp: 5556–5564

Ultra-compact fiber-optic two-photon microscope for functional fluorescence imaging in vivo

Christoph J. Engelbrecht, Richard S. Johnston, Eric J. Seibel, and Fritjof Helmchen  »View Author Affiliations

Optics Express, Vol. 16, Issue 8, pp. 5556-5564 (2008)

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We present a small, lightweight two-photon fiberscope and demonstrate its suitability for functional imaging in the intact brain. Our device consists of a hollow-core photonic crystal fiber for efficient delivery of near-IR femtosecond laser pulses, a spiral fiber-scanner for resonant beam steering, and a gradient-index lens system for fluorescence excitation, dichroic beam splitting, and signal collection. Fluorescence light is remotely detected using a standard photomultiplier tube. All optical components have 1 mm dimensions and the microscope’s headpiece weighs only 0.6 grams. The instrument achieves micrometer resolution at frame rates of typically 25 Hz with a field-of-view of up to 200 microns. We demonstrate functional imaging of calcium signals in Purkinje cell dendrites in the cerebellum of anesthetized rats. The microscope will be easily portable by a rat or mouse and thus should enable functional imaging in freely behaving animals.

© 2008 Optical Society of America

OCIS Codes
(170.0110) Medical optics and biotechnology : Imaging systems
(170.2150) Medical optics and biotechnology : Endoscopic imaging
(170.2520) Medical optics and biotechnology : Fluorescence microscopy
(170.3880) Medical optics and biotechnology : Medical and biological imaging
(180.2520) Microscopy : Fluorescence microscopy
(180.5810) Microscopy : Scanning microscopy

ToC Category:
Medical Optics and Biotechnology

Original Manuscript: February 12, 2008
Revised Manuscript: March 28, 2008
Manuscript Accepted: April 1, 2008
Published: April 4, 2008

Virtual Issues
Vol. 3, Iss. 5 Virtual Journal for Biomedical Optics

Christoph J. Engelbrecht, Richard S. Johnston, Eric J. Seibel, and Fritjof Helmchen, "Ultra-compact fiber-optic two-photon microscope for functional fluorescence imaging in vivo," Opt. Express 16, 5556-5564 (2008)

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