In vivo brain imaging using a portable 2.9 g two-photon microscope based on a microelectromechanical systems scanning mirror

James H. Clark Center for Biomedical Engineering and Sciences, Stanford University, Stanford, California 94305, USA.
Optics Letters (Impact Factor: 3.29). 09/2009; 34(15):2309-11. DOI: 10.1364/OL.34.002309
Source: PubMed


We present a two-photon microscope that is approximately 2.9 g in mass and 2.0 x 1.9 x 1.1 cm(3) in size and based on a microelectromechanical systems (MEMS) laser-scanning mirror. The microscope has a focusing motor and a micro-optical assembly composed of four gradient refractive index lenses and a dichroic microprism. Fluorescence is captured without the detected emissions reflecting off the MEMS mirror, by use of separate optical fibers for fluorescence collection and delivery of ultrashort excitation pulses. Using this microscope we imaged neocortical microvasculature and tracked the flow of erythrocytes in live mice.

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