Light-sheet microscopy enabled by a miniaturized plane illuminator.

We present a implementation method of light-sheet microscopy utilizing a highly miniaturized device that produces light-sheet illumination while immersed in the sample container. Our miniaturized plane illuminator (MPI) internally equips a two-axis beam-scanning mechanism based on a magnetostatically driven optical fiber cantilever. A light sheet is produced by fast scanning of the focused beam in an axis while the illumination plane can move in the other axis for positioning and 3D imaging. Our MPI device is so compact in a 1.5 mm-thick needle form that it can be conveniently placed in the right vicinity of the imaging sample. Because the illumination is directly given in the sample-surrounding medium, a great deal of operational flexibility is obtained with an uncompromised beam quality. We could build a light-sheet microscopy system with a conventional inverted microscope frame by attaching our MPI upgrade kit as an add-on module. In this study, the optical and electromechanical characteristics of our MPI device were carefully investigated. As well, light-sheet microscopy imaging of various samples was performed to validate the practical power of our technique. We found our MPI can provide a low-cost and easy-to-use imaging mode, and make the light-sheet microscopy more available in various applications.