Processing Of Raw Data - Agilent Technologies InfinityLab LC Series User Manual

1
Introduction to the Fluorescence Detector
Analytical Information From Primary Data

Processing of Raw Data

If the lamp flashes at single wavelength and high-power, then the fluorescence
data rate is 296 Hz. That means that your sample is illuminated 296 times per
second, and any luminescence generated by the components eluted from the
column is measured 296 times per second.
If the "economy" or multi-wavelength mode is set, then the flash frequency is
74 Hz.
Figure 15 LAMP: Frequency of Flash, Fluorescence, and Phosphorescence
You can improve the signal-to-noise characteristics by disabling the "economy"
mode.
Disabling the "economy" mode will shorten the lifetime of the lamp significantly. Consider
N O T E
lifetime saving by switching off the lamp after the run is completed.
The data resolution is 20 bit at a response time of 4 s (default, which is
equivalent to a time constant of 1.8 s and appropriate for standard
chromatographical conditions). Weak signals may cause errors in
quantification because of insufficient resolution. Check your proposed
PMTGAIN. If it is significantly distant from your setting, change your method
or check the purity of your solvent. See also "Finding the Best Signal
Amplification" on page 124.
Agilent InfinityLab LC Series 1260 Infinity II FLD User Manual 29