Agilent Technologies Cary 8454 Installation Manual page 56

4 Installing Accessories
Optical Filter Wheel
100
80
60
40
20
0
Figure 20
Table 4
Position
0
1
2
3
The choice of when to use a filter and which filter to use should be made only
after considering all the factors that affect your measurements. If you decide
that a filter is needed, you should choose a filter that transmits the
wavelengths needed for analytical information and that blocks the
wavelengths that contribute to sample degradation. Often, your final choice
will be a compromise since sometimes even the light at the wavelengths of
analytical interest can affect your sample.
If you do not need a filter for a group of measurements, you can move the filter
wheel to position zero. This permits full light transmission. When you will not
be using the filter wheel for an extended period of time you should remove the
filter wheel assembly from the cell holder and store it in a clean plastic bag.
The optical filters of the filter wheel must be kept clean. Dirty filters interfere
with light transmission and lower the spectrophotometer performance. These
filters may be cleaned with isopropanol and photographic lens tissues.
56
0
1
2
3
190 200 300 400
Transmission characteristics of filter wheel filters
Filter wheel positions
Filter
None
UV roll-off
265 nm UV cut-off (at 50%T)
295 nm UV cut-off (at 50%T)
Agilent Cary 8454 UV-Visible Spectroscopy System Installation Guide
500 600 700 800 820