From: first.last@iki.fi   
      
   Phil Hobbs  writes:   
   >>>>>>>>> Hi, all,   
   >>>>>>>>>   
   >>>>>>>>> I have a gig to design a microplate reader for a new bioassay system.   
   >>>>>>>>> To match the reagent systems, it needs to work over a range of   
   >>>>>>>>> wavelengths in the 340-500 nm region, none of which is particularly   
   >>>>>>>>> well   
   >>>>>>>>> matched to mercury emission lines.   
   ...   
   > Target is +- 0.0002 absorption units over a 2 AU range.  Not difficult   
   > from a SNR point of view, but you don't get stability like that by   
   > accident.   
      
   We've done a project that had specs close to this; 0-2 OD at 0.0001 and   
   going to 3.5/0.05 400-700nm. We ended up combining multiple LEDs with a 7:1   
   fiber   
   bundle. Loses a lot of light, but the measurement package needs a fiber   
   coupled source anyway. If I remember correctly, we had some dips at 430   
   and 480nm due to not finding suitable high power LEDs.   
      
   --   
   Mikko OH2HVJ   
      
   --- SoupGate-Win32 v1.05   
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