History of Phase-Modulation Fluorometers

The next apparent difficulty is measurement of the phase angle and modulation at high frequencies. Ibe measure meats appear more diffrcidt when one realizes that resolution of nMihieiqNMiential decays reipiires accuraqr near 0l2 m phase and 0.5% (O.OQS) in modulation and that diis accuracy needs to be maintained from 1 to 200 MHz. In 

Hie ros -coiTeladcioiiiethodissurpcisinglyrobQSt.The harmonic content (frequency components) of almost any eatcitadon profile can be used if it contains frequency components that are qroefaronized with the detector. Both pulsed lasers and syocliroCron ladiadon have been used as 

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