Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual page 25

UltiMate 3000 Series:
Fluorescence Detectors FLD-3100 and FLD-3400RS
When the light exits the flow cell, it is focused by the emission optics (no. 6) through the
emission monochromator (no. 8).
A cut-off filter, which lets only light above a certain wavelength pass, is located before the
emission monochromator. In the FLD-3100, the filter has a fixed cut-off wavelength
(280 nm). In the FLD-3400RS, a filter wheel (no. 7) is installed. With the help of a motor the
wheel can be moved to 5 different positions with different cut-off wavelengths. The selectable
filter helps to achieve an even better sensitivity and increase flexibility during method
development.
The emission monochromator transmits only the light with the user-selected emission
wavelength to a photomultiplier tube (PMT) (no. 9), where the light is measured. A second
optional red-sensitive photomultiplier tube (no. 10) measures light in the near infrared region
(up to 900 nm).
Fig. 3: Optics setup (schematic)
Operating Instructions Page 17