Patent ID: 7133202

Claim:
A dynamic gain tilt equalizer, comprising: a first collimator for collimating a first light beam; a first walk off crystal for receiving the collimated light beam from the collimator and dividing the first light beam into a first ordinary beam and a first extraordinary beam; a first half-wave plate for receiving the first ordinary beam from the first walk off crystal; a polarization beam splitter for receiving the first extraordinary beam from the first walk off crystal and the first ordinary beam from the first half-wave plate; a Faraday rotator for receiving the first ordinary beam and the first extraordinary beam from the polarization beam splitter; a 22.5° cut half-wave plate for receiving the first ordinary beam and the first extraordinary beam from the Faraday rotator; a rotative half-wave plate for receiving the first ordinary beam and the first extraordinary beam from the 22.5° cut half-wave plate; a second walk-off crystal for receiving the first ordinary beam and the first extraordinary beam from the rotative half-wave plate, for dividing the first ordinary beam into a second ordinary beam and a second extraordinary beam, and for dividing the first extraordinary beam into a third ordinary beam and a third extraordinary beam; a linear tilt optical filter for receiving the second and the third ordinary beams from the second walk-off crystal; a first mirror for reflecting the second and the third extraordinary beams back into the second walk-off crystal and for reflecting the second and the third ordinary beams back into the second walk-off crystal after passing through the linear tilt optical filter a second time, whereby, in the second walk-off crystal, the second ordinary beam combines with the second extraordinary beam to form a second light beam and the third ordinary beam combines with the third extraordinary beam to form a third light beam; a second mirror for receiving the second light beam and the third light beam from the polarization beam splitter; a third walk-off crystal for receiving the second and the third light beams from the second mirror and for combining the light beams into a fourth light beam; and a second collimator for receiving the fourth light beam from the third walk-off crystal.