In the context of beam splitters, attenuation can occur due to several factors, including absorption, reflection, and scattering. What are Beam Splitters? A beam splitter (or beamsplitter, power splitter) is an optical device which can split an incident light beam (e. a laser beam) into two (or sometimes more) beams, which may or may not have the same optical power (radiant flux). Beamsplitters are often classified according to their construction: cube or plate. Beam splitting/combining is difficult and expensive; avoid it if you can. Polarizing cube beamslitters have better polarization separation, but would be. What happens to the photons coming from A2 when they hit B? Do they all reflect toward the detector, or do 50% of them transmit through and up? The trivial mistake here is to assume that beams are flat and that the optical setup absorbs all the beam power that goes into it.
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