Patent ID: 6441961
Filing Date: 2002-08-27
Classification: G02B,H04J

Abstract:
An optical interleaver apparatus, comprising:(a) a first birefringent element, having an optic axis oriented such that the first birefringent element separates an input optical signal into a first beam having a first polarization and a second beam having a second polarization; (b) a first waveplate optically coupled to the first birefringent element, wherein the first waveplate rotates a polarization of light in a first wavelength range, but not a second wavelength range; (c) a second birefringent element optically coupled to the first waveplate, wherein the second birefringent element separates the first beam into a third beam containing light in the first wavelength range and a fourth beam containing light in the second wavelength range, wherein the third beam and the fourth beam have complementary polarizations; wherein the second birefringent element separates the second beam into a fifth beam containing light in the second wavelength range and a sixth beam containing light in the first wavelength range, wherein the fifth beam and the sixth beam have complementary polarizations but the polarizations of the third and fifth beams are substantially the same as each other and the polarizations of the fourth and sixth beams are substantially the same as each other; (d) a polarization rotation device optically coupled to the second birefringent element; and (e) at least one retro-reflector optically coupled to the polarization rotation device, wherein the at least one retro-reflector reflects the third, fourth fifth and sixth beams traveling along forward paths from the polarization rotation device back towards the polarization rotation device and the second birefringent element along reverse paths such that the second birefringent element combines the third beam with the sixth beam to form a first output optical signal and the second birefringent element combines the fourth beam with the fifth beam to form a second output optical signal.