Extended working distance selective plane illumination by dihedral array reflectors (SPIDAR)

We present an LSFM architecture that uses a one-dimensional dihedral corner reflector array (DCRA) to generate structured plane illumination. This configuration yields an extended working distance of 3.5 cm while maintaining a light-sheet thickness of approximately 2.4 μm across an 80 μm axial range. System characterizations demonstrate a lateral resolution of ~0.5 μm and a resolution of 2.4 μm. The system resolved lipid storage dynamics, distinguishing ~0.6 μm lipid droplets in fed cells from larger, irregular tubular condensed fatty acids in fasted cells. By expanding the sample space without sacrificing subcellular resolution, this DCRA-based approach reduces optical complexity and provides a versatile framework for volumetric imaging of large-scale samples.