(a) Emission spectroscopy setup for nanoparticles in solution. The argon laser excites the sample, and the corresponding emitted light is collected by a system of lenses that directs it to a monochromator. The last is backed up by a detector and operational amplifier. The chopper modulates the laser light for amplification. (b) Near-Field Optical Microscope setup. A sample is placed on the sample holder and is excited by the laser via the tapered SNOM tip. Two modes for light collection are possible, transmission through the transmission module optics or reflection, through the collection objective. The corresponding spectrometer is for near-field spectroscopy and the SNOM light detector for near-field imaging of the collected signal.