  We describe the apparatus of a fluorescence optical microscope with both
single-photon and two-photon non-diffracting light sheets excitation for large
volume imaging. With special design to accommodate two different wavelength
ranges (visible: 400-700 nm, and near infrared: 800-1200 nm), we combine the
line-Bessel sheet (LBS, for single-photon excitation) and the scanning Bessel
beam (SBB, for two-photon excitation) light sheet together in a single
microscope setup. For a transparent thin sample where the scattering can be
ignored, the LBS single-photon excitation is the optimal imaging solution. When
the light scattering becomes significant for a deep-cell or deep-tissue
imaging, we use SBB light-sheet two-photon excitation with a longer wavelength.
We achieved nearly identical lateral/axial resolution of about 350/270 nm for
both imagings. This integrated light-sheet microscope may have a wide
application for live-cell and live-tissue three-dimensional high-speed imaging.
