Waters 2996, Operator'S Manual

Page: 52 / 84

30 Principles of the 2996 PDA Detector Optics
4
Figure 4-1 Optics Assembly Light Path
Table 4-1 describes the optics assembly components in the 2996 Detector.
Table 4-1 Optics Assembly Components
Component Function
Lamp and lamp
optics Focuses light from the deuterium source lamp via a mirror through a
beamsplitter to the flow cell.
Beamsplitter and
reference diode Reflects part of the light back to a reference diode, which measures
the intensity of the light emitted by the lamp. The detector uses this
measurement to keep the lamp output constant.
Flow cell
assembly Houses the segment of the flow path (containing eluent and sample)
through which the polychromatic light beam passes. This arrange-
ment of optical components, with the flow cell positioned between
the lamp and the grating, is commonly called reversed optics.
Reference
Diode
Beamsplitter
Assembly
50- µ m Aperture
Lamp and
Lamp Optics
Spectrographic
Mirror and Mask
Shutter
Assembly
Flow Cell
Assembly
Grating
Photodiode
Array