Frequency-doubled Ar-ion laser

Frequency-doubled Ar ion lasers, 19 115 Frequency doublers, commercial,... 

At the opposite end of the spectrum, UV sources for CE-LIF are becoming increasingly popular. UV radiation is capable of inducing fluorescence in many intrinsic fluorophores, including a number of biologically relevant molecules. The frequency-doubled Ar-ion laser (257 nm) was one of the first examples reported of UV-excitation for CE-LIF, and yielded improvements in LODs for a number of substances, such as conalbumin (1.4 x 10 M). As another example, a frequency-doubled Kr laser operating at 284 nm has been used for the analysis of neuropeptides and small biomolecules, and exhibited LODs for tryptophan of 800 zmol. In addition to frequency-doubled ion lasers, a number of relatively inexpensive pulsed lasers such as frequency quadrupled YAG (266 nm), KrF (248 nm), and hollow-cathode metal vapor lasers have appeared, which provide deep-UV excitation (e.g., 224 and 248 nm). ... 

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