Relaxing Coherence Requirements on Laser Sources for Nanoscopy through Optical Fiber Technique
High numerical-aperture (NA) focusing of cylindrical vector beams (CVBs) typically requires costly, high-quality lasers to supply a stable vector pupil field. Here, we introduce fiber-conditioned vectorial nanofocusing, in which an optical-fiber-based mode-selective coupler projects a strongly distorted beam of a diode...