Agilent Technologies 1100 Series Reference Manual page 40

2 How to optmize the Detector
Figure 13
A wide slit uses more of the light shining through the flow cell. This gives
lower baseline noise as shown in
Slit width 1 nm
Slit width 4 nm
Slit width 16 nm
Figure 14
However, with a wider slit, the spectrograph's optical resolution (its ability to
distinguish between different wavelengths) diminishes. Any photodiode
receives light within a range of wavelength determined by the slit width. This
explains why the fine spectral structure of benzene disappears when using a
16-nm wide slit.
40
16 nm
4 nm
1 nm
Benzene at 1, 4 and 16 nm slit width
Influence of the Slit Width on Baseline Noise
Figure 14.
1100 Series DAD and MWD Reference Manual