(Laser Induced Fluorescence (LIF
Fluorescence which is a form of luminescence, is the emission of light due to the absorption of light or other electromagnetic radiation by a matter. Generally the emitted light compared with absorbed one has higher wavelength and lower energy. The most common example of fluorescence happens by applying invisible UV spectrum as the absorption radiation which emits the visible light.
Laser Induced Fluorescence (LIF) is an optical technique that molecules/atoms will be excited after absorbing the laser light, and then spontaneously emits light. Usually a few micro/nano-seconds after absorbing the electromagnetic radiation, excited atoms/molecules emit light at a wavelength greater than the absorption one. LIF technique is appropriate to identify species, investigate molecules structure, and measure physical properties such as PH, temperature, pressure, and concentration in the flow field.
