Figure 4
From: Ultrasmall all-optical plasmonic switch and its application to superresolution imaging
Experimental setup.
(a) Optical construction of the multi-wavelength confocal microscope. A 592-nm beam plus a vortex phase plate is incorporated to improve resolution. SC: supercontinuum; BS: beamsplitter; PMT: photomultiplier tube. (b) Measured point spread function of 543 nm and 592 nm (with vortex phase plate).
