Teledyne T100 Manuale Utente

Two optical lenses are used to focus and optimize the path of light through the 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

2 

reaches the reference detector. Conversely, this also makes 

sure that the volume of sample gas affected by the excitation beam is similar to the 
volume of fluorescing SO

2

* being measured by the PMT, eliminating a possible source 

of measurement offset. 

06807C DCN6650