Patent ID: 6728019
Filing Date: 2004-04-27
Classification: B82Y,G02F,H01S

Abstract:
An optical gate comprising:a polarization divider to divide an optical signal into two orthogonal polarization components and to output them as a first polarization component which precedes in the time base and a second polarization component which follows the first polarization component in the time base; a semiconductor optical amplifier having a band edge wavelength to modulate the phase of the second polarization component output from the polarization divider according to a control light; an assist light supplier to supply to the semiconductor optical amplifier an assist light to help recovering refractive index variation of the semiconductor optical amplifier caused by the control light; a polarization combiner to combine the first and second polarization components of the optical signal output from the semiconductor optical amplifier so as to adjust the outputted first and second polarization components in a same time location; and a polarization extractor to extract a predetermined polarization direction component from the adjusted polarization components output from the polarization combiner.