IQF NLOM

NLOM is a totally non-invasive technique based on the excitation of the non-linear optical response that is generated in any material upon excitation with laser pulses of very short duration, in the range of femtoseconds. NLOM can operate under different modalities (i.e. Multiphoton Excitation Fluorescence, Second and Third Harmonic Generation). The technique can be applied to substrates that are transparent in the IR region, such as varnishes, glues, painting layers, corrosion layers on glass or metal substrates, parchments and others. It provides information, on three dimensions and with microscopic resolution, on the presence of layers of different chemical nature, their thickness or their crystalline or hierarchical internal organization. Lateral and axial resolutions are in the micrometre range and the penetration depth can reach up to 1 mm, depending on the sample transparency. The technique does not require any preparation or sampling and derives information in a totally non-invasive way. Via the combined use of the above mentioned different NLOM modalities it is possible to assess on the presence of layers of different chemical nature, their thickness or their crystalline or hierarchical internal organization. It is also possible to obtain highly contrasted 3D images at the micrometer scale. The NLOM equipment of this FIXLAB uses a Ti:sapphire laser oscillator emitting at 800 nm with pulses of 70 femtoseconds.

Non linear optical microscopy (nlom)

Analysis Method

1.0