Light sheet fluorescence microscopy: Advancing biological discovery with more dimensions, higher speed, and lower phototoxicity

Fluorescence microscopy has proved to be essential for seeing life in a grain of a cell. Classic epifluorescence microscopes, such as wide-field microscopes and laser scanning confocal microscopes, have been widely used for biology research over the past few decades. The goal of fluorescence microscopy is to observe the structure and function of cellular events across time and three-dimensional (3D) space with spatiotemporal resolution as high as possible. However, conventional epifluorescence microscopes illuminate the entire 3D volume of the sample while detecting signals only from the 2D focal plane, thereby leading to low photon utilization and high phototoxicity issues that notably prevent high-resolution imaging of live biological specimens (Figure 1A). It becomes increasingly noteworthy that the massively emerging biomedical applications are posing significant challenges to current fluorescence microscopy techniques.