Patent ID: 7260331

Claim:
An optical pulse demultiplexer comprising: an optical splitter to split a pulse signal light of a signal wavelength at a bit rate into a first light portion and a second light portion; an optical clock generator to generate an optical clock of a control wavelength at a predetermined frequency lower than a frequency corresponding to the bit rate of the first light portion output from the optical splitter; a saturable absorber having a transmission factor relative to the signal wavelength, wherein the transmission factor varies due to absorption of a light of the control wavelength by the saturable absorber; an optical path to apply the optical clock output from the optical clock generator to the saturable absorber through one side of the saturable absorber; an optical bandpass reflection mirror disposed on the optical path and to reflect a light of the signal wavelength and to transmit a light of the control wavelength; an optical bandpass filter to transmit a light of the signal wavelength and to block a light of the control wavelength; and an optical circulator disposed on another side of the saturable absorber and to apply the second light portion output from the optical splitter to the saturable absorber and to apply an output light from the saturable absorber into the optical bandpass filter, wherein the pulse signal light of the signal wavelength reciprocates in the saturable absorber and wherein each optical pulse of the pulse signal light of the signal wavelength enters the saturable absorber almost simultaneously with different optical pulses of the optical clock on the ways of going and returning.