PDA-100 Photodiode Array Detector
2-4
Doc. 031644-02 9/03
2.3
Optical System
Figure 2-3 is a schematic of the PDA-100 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 separated
into its component wavelengths and diffracted to the photodiode array. Each diode
measures a narrow portion of the spectrum.
Figure 2-3. PDA-100 Optical System
Grating
Slit
Flow Cell
Filter Paddle
Photodiode Array
Spectrograph Lens
Source Lens
Visible Focus Lens
Deuterium Lamp
Tungsten Lamp