Reducing intensity of xenon lamp

[riclambo]

Hello Forum,
An optics question here. I'm using a Xenon continuous arc lamp as a source of broadband light together with a spectrometer for an absorption experiment. However the lamp is too bright and is saturating the spectrometer. Is there a standard way to reduce the intensity of the lamp, using a mirrors and/or filters? The situation is complicated by the fact that the diameter of the beam from the arc lamp is on the order of a few centimeters and it has to be fed into a fibre optic cable.

Regards,
R

 

[Redbelly98]

I would use a neutral density filter, preferally the absorptive kind, to reduce the beam power. A 1" (2.5 cm) square filter size is pretty standard, but 2" (5 cm) squares are available too.

In the USA you should be able to get them from Newport, Melles Griot, or Thorlabs. Here is a link to Newport:
http://www.newport.com/Absorptive-Neutral-Density-Filters/141138/1033/catalog.aspx