Multi-azimuthal illumination total internal reflection microscopy based on dual wedge prism design.

High-quality and label-free total internal reflection microscopy with multi-azimuthal evanescent wave (EW) illumination is proposed based on a dual wedge prism (WP) design. The novel, to our knowledge, feature of this design is the use of two wedge prisms through the rotation of which evanescent waves with all-directional wave vectors are excited sequentially. By joining a half-wave plate (HWP), it is feasible to make the generated evanescent waves possess the same polarization directions at all azimuthal angles. Thus, it has the advantages of simple structure, ease of use, and low cost. In the experiments, we can resolve the high-fidelity and high-resolution structures of fabricated resolution test targets and silver nanowire (NW) samples that remain unresolved in a single direction total internal reflection microscope.