Thermo Scientific 074114, Operator'S Manual

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Dionex PDA Operator’s Manual
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Doc. 065378-01 1/12
2.3 Optical System
Figure 2-4 is a schematic of the Dionex PDA optical system.
Light from the tungsten lamp is focused through an opening in the internal
structure of the deuterium lamp. Light from the tungsten and deuterium lamps is
then focused through the flow cell by the source lens. After exiting the cell, the
light passes through the spectrograph lens to the filter paddle and is focused into
the slit. The light then passes through the slit to the grating, where it is diffracted
into the component wavelengths. Measurement of the light occurs at the
photodiode array. Each diode measures a narrow portion of the spectrum.
Figure 2-4. Dionex PDA Optical System
Grating
Slit
Flow Cell
Filter Paddle
Photodiode Array
Spectrograph Lens
Source Lens
Visible Focus Lens
Deuterium Lamp
Tungsten Lamp