Multiphoton microscopy is regularly used to produce high-resolution images of in vivo neural structure, but strategies to increase both the imaging depth and field of view are needed. To aid with deep imaging, we present an ultrafast laser system consisting of a custom ytterbium fiber amplifier and diamond Raman laser that output high powers (6.5 W, 1.3 W) at valuable wavelengths (1060 nm, 1250 nm) for multiphoton excitation of red-shifted fluorophores. The entire system is relatively inexpensive and simple to construct as compared to alternative custom and commercial excitation options. The 80 MHz repetition rate of each laser in the system is also notable, as it allows a resonant scanner to be used for imaging to dramatically increase acquisition rate. In this work we demonstrate the ability to acquire neuronal images, and the capability to image vasculature at deep locations (<1 mm) within the mouse cerebral cortex. We also present a strategy to image over a large field of view involving a resonant scanner and make use of this to monitor neurovascular structure longitudinally within a volume of one cubic millimeter.
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