Calculate how much radiant power goes through an optical system

[rp895]

Hi,
I have to do a rediometric analysis on an optical system , basically calculate how much radiant power goes through an optical system from the target to the detector, passing through multiple lenses and prisms then to the detector. I am having some problem with radiance and irradiance calculations going through a series of lenses and especially the prism.

Any help will be appreciated!
rp895

 

[Claude Bile]

The rule of thumb is that you lose 4% (for visible wavelengths) at each component due to Fresnel reflections, unless of course there are antireflection coatings present, in which case the 4% will be a much lower figure.

If you know the loss in dB at each component, all you need to do is add all the losses in dB to get the total loss.

This is of course making the assumption that no light is lost due to bad alignments etc.

Claude.