Laser Induced Fluorescence

For other uses, see LIF. Laser-induced fluorescence (LIF) is a spectroscopic method used for studying structure of molecules, detection of selective species and flow visualization and measurements.The species to be examined is excited with help of a laser. The wavelength is often selected to be the one at which the species has its largest cross section. The excited species will after some time, usually in the order of few nanoseconds to microseconds, de-excite and emit light at a wavelength larger than the excitation wavelength. This light, fluorescence, is measured.
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A method for measuring the relative amount of soil and/or groundwater with an in-situ sensor.