[mems-talk] Can someone show me an actual photo of a Mylar Beamsplitter

[Guangchi Archie Xuan]

Maybe some of you have a FTIR spectrometer that could work in Far-IR region. I'm wondering whether you could send me a photo showing the mylar beamsplitter. 
   
  I am trying to make one for my spectrometer but I have never seen a real one in the first place so I'm not sure where mine went wrong. I used a stretched sheet of 25um, 50um and 75um thickness Mylar for our beamsplitter but our Michelson interferometer couldn't get any interferogram. 
   
  So if you could show me a real one that'll be great! Also, any advice is warmly welcome.