124 1220 Infinity II LC System User Manual
8
Detector Description
Agilent 1220 Infinity II LC Diode Array Detector (DAD)
Sample and Reference Wavelength and Bandwidth
The detector measures absorbance simultaneously at wavelengths from 190 to
950 nm. Two lamps provide good sensitivity over the whole wavelength range.
The deuterium discharge lamp provides the energy for the UV range (190 to
400 nm) and the tungsten lamp emits light from 400 to 950 nm for the visible
and short wave near infrared.
If you know little about the analytes in your sample, use both lamps and store
all spectra over the full wavelength range. This provides full information but
fills up your disk space rather quickly. Spectra can be used to check a peak’s
purity and identity. Spectral information is also useful to optimize wavelength
settings for your chromatographic signal.
The detector can compute and store at run time up to 8 signals with these
properties:
• sample wavelength, the center of a wavelength band with the width of
sample bandwidth (BW), and optionally
• reference wavelength, the center of a wavelength band with the width of
reference bandwidth.
Table 22 Peak Width — Response Time — Data Rate
Peak Width [minutes] Response Time [seconds] Data Rate [Hz]
<0.0025 0.025 80
>0.0025 0.05 80
>0.005 0.1 40
>0.01 0.2 20
>0.03 0.5 10
>0.05 1.0 5
>0.10 2.0 2.5
>0.20 4.0 1.25
>0.40 8.0 0.62
>0.85 16.0 0.31