Optical Lenses; Figure 12-6: Effects Of Focusing Source Uv In Sample Chamber - Teledyne t100 Operation Manual

Teledyne API - T100 UV Fluorescence SO
12.1.8.

OPTICAL LENSES

Figure 12-6:
06807F DCN7335
Analyzer
2
Two optical lenses are used to focus and optimize the path of light through the sample
chamber.
Effects of Focusing Source UV in Sample Chamber
A lens located between PMT and the sample chamber collects as much of the fluoresced
UV created there as possible and focuses it on the most sensitive part of the PMT's
photo cathode.
Another lens located between the excitation UV source lamp and the sample chamber
collimates the light emitted by the lamp into a steady, circular beam and focuses that
beam directly onto the reference detector. This allows the reference detector to
accurately measure the effective intensity of the excitation UV by eliminating the effect
of flickering inherent in the plasma arc that generates the light.
Ensure that all of the light emitted by the source lamp, passes though the 214 nm filter
and not absorbed by the SO
sure that the volume of sample gas affected by the excitation beam is similar to the
volume of fluorescing SO
of measurement offset.
reaches the reference detector. Conversely, this also makes
2
* being measured by the PMT, eliminating a possible source
2
Principles of Operation
271