The NLOM system consists in an upright microscope which uses an ultrashort laser system as excitation light source. The laser is a mode-locked Ti:Sapphire oscillator emitting at 800 nm, delivering 70 femtosecond pulses at a repetition rate of 80 MHz. A variable neutral density filter is used to control the laser power reaching the sample to ensure non-damaging measurement conditions. The microscope is based on objective lenses with high numerical aperture. The sample, or object of study, is placed on a 3D, micrometer resolution motorized translation stage that selects the position of the focal spot of the laser on the sample. The lateral and axial resolution of measurements are 1 and 2 micrometres, respectively. The non-linear optical signal is collected in the reflection mode and measured with a photomultiplier and an adequate combination of optical filters. Signal discrimination is enhanced with the use of a lock-in amplifier.

Dataset/Data package (images, spectra, other)
Report
Fluorescence depth profile in *.txt

Noncontact (no physical contact)
Nondestructive (no permanent damage or alteration)
Noninvasive (no physical alteration)

Laser (Spectra Physics), Lock-in amplifier (Stanford Research Systems), Photomultiplier (ET Enterprises)

Custom

small spot
micro