Light Sheet Fluorescence Microscopy is a highly efficient technique (in terms of excitation and detection of the signal) to observe, in high resolution (x, y and z), living samples. It works by illuminating the sample with a light sheet, normally produced using a cylindrical lens. The generated fluorescence signal is recorded in a perpendicular way to the light sheet. Until now, LASERS, considered as point sources, had to be used to ensure the production of a thin light sheet. In this project, I present a new way to create a Light Sheet using LEDs or any extended source in general in combination with the use of a Photonic Lantern (PL). This has the advantage that they will produce a more homogenous illumination, have a large bandwidth, produce no speckle or any interference patterns and is not expensive. Thus, in this work, I will introduce the working principle of the Light Sheet Fluorescence Microscope (LSFM), then I will show the different kind of sources of light to generate a Light Sheet, including the use of extended sources. Then I will explain the Photonic Lantern, its constructions, and its characterization. This allows to present, for the first time, the combined use of a PL with an extended source for obtaining high-resolution images in a light sheet microscope. Finally, I will show the use of LEDs and PL as the ideal tool to produce high-resolution images of non-fluorescently labeled samples using elastic scattering as a contrast mechanism. Importantly, this opens up a new range of applications in which fluorescence signal is too weak (for example for fast imaging) or for conditions in which labeling is not possible at all.