Agilent InfinityLab LC Series 1260 Infinity II FLD User Manual
15
Introduction to the Fluorescence Detector
1
How the Detector Operates
How the Detector Operates
Luminescence Detection
Luminescence
, the emission of light, occurs when molecules change from an
excited state to their ground state. Molecules can be excited by different forms
of energy, each with its own excitation process. For example, when the
excitation energy is light, the process is called
photoluminescence
.
In basic cases, the emission of light is the reverse of absorption, see
on page 15. With sodium vapor, for example, the absorption and emission
spectra are a single line at the same wavelength. The absorption and emission
spectra of organic molecules in solution produce bands instead of lines.
Figure 3
Absorption of Light Versus Emission of Light
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