VARIABLE POLARIZATION INDEPENDENT OPTICAL POWER SPLITTER

摘要

An optical power splitter for variably splitting an arbitrarily polarized light beam into two or more light beams, is disclosed. An input light beam "A" is received and spli t it into two output light beams "M" and "N" where the optical power ratio of the two output ligh t beams "M" and "N" is adjusted to a desired ratio by controlling a variable polarization rotator (liquid crystal unit). The polarization components "P" and "S" of the input light beam "A" a re separated in a first polarization separator (birefringent displacer), then processed throug h the variable polarization rotator and a second polarization separator. Finally the processed optical components are recombined in a polarization combiner so as to constitute the desired output light beams "M" and "N" having the desired optical power ratio "R". The polarizati on independence of the power split is thus achieved through the stratagem of processing the "P" and "S" polarized components of the input light beam "A" separately - resulting in four light beams "H", "I", "L" and "K" which appropriately combined in the polarization combines yield the output light beams "M" and "N". A number of embodiments are disclosed with different optical technology in the second polarization separator (Wollaston prism) and the variable polarizati on rotator (mechanically or electro-mechanically adjusted wave plate), with optical deflection means (for physical compactness) and photo detectors (for optical power monitoring), as well as an embodiment for a four-way split.