Optical Pulse Conditioning Apparatus and Methods for Conditioning Optical Pulses

Abstract

A pulse conditioning apparatus can comprise a signal splitter for splitting a pulsed input signal into first and second pulsed signals; a spectrally dispersive element configured for subjecting the first pulsed signal to a spectral dispersion for compressing or stretching the first pulsed signal, the first and second pulsed signals being subjected to substantially different spectral dispersion; and a combiner for combining the first and second pulsed signals to an output pulsed signal, the output pulsed signal output comprising pulses having a surge pulse portion and a base pulse portion, at least one of the portions derived at least in part from the spectral dispersion and attendant compression or stretching of the first pulsed signal.

1 . A pulse conditioning apparatus, comprising:
 a signal splitter for splitting a pulsed input signal into first and second pulsed signals;   a spectrally dispersive element configured for subjecting the first pulsed signal to a spectral dispersion for compressing or stretching the first pulsed signal, the first and second pulsed signals being subjected to substantially different spectral dispersion;   a combiner for combining the first and second pulsed signals to an output pulsed signal, the output pulsed signal comprising pulses having a surge pulse portion and a base pulse portion, at least one of the portions derived at least in part from the spectral dispersion and attendant compression or stretching of the first pulsed signal.   
     
     
         2 . The pulse conditioning apparatus of  claim 1  comprising a polarization beam splitter, said signal splitter and said beam combiner each comprising said polarization beam splitter. 
     
     
         3 . The pulse conditioning apparatus of  claim 1  comprising a polarization controller optically upstream of the signal splitter for allowing the polarization state of the pulsed input signal to be changed by a user. 
     
     
         4 . The pulse conditioning apparatus of  claim 1  comprising a time delay apparatus for introducing a time delay to the second pulsed optical signal. 
     
     
         5 . The pulse conditioning apparatus of  claim 1  wherein said spectrally dispersive element is configured for compressing the first pulsed signal. 
     
     
         6 . A method of conditioning pulses, comprising:
 splitting an input signal comprising input pulses into first and second pulsed signals;   subjecting the first and second one of the first and second pulsed signals to spectral dispersion so as to temporally compress or stretch pulses of the one of the first and second signals, the first and second pulsed signals undergoing substantially different spectral dispersion; and   combining the first and second pulsed signals to form an output signal comprising pulses having a surge pulse portion and a base pulse portion, at least one of the portions derived at least in part from the spectral dispersion and attendant compression or stretching of the one of the first and second pulsed signals.   
     
     
         7 . The method of  claim 6  comprising changing the state of polarization of pulses of the input signal. 
     
     
         8 . The method of  claim 6  comprising varying the polarization state of the input signal so as to vary the relative optical energies of the surge and base pulse portions of the output pulses. 
     
     
         9 . The method of  claim 6  comprising varying a time delay of one of the first and second pulsed signals so as to change the temporal relationship of the surge and base pulse portions of the output pulses. 
     
     
         10 . The method of  claim 6  comprising varying the optical energy of pulses of at least one of the first and second pulsed signals so as to vary the optical energy of at least one of the surge and base pulse portions. 
     
     
         11 . The method of  claim 6  wherein at least one of the splitting and combining comprises using polarization discrimination. 
     
     
         12 . The method of  claim 6  wherein both of the splitting and combining comprise using polarization discrimination. 
     
     
         13 . The method of  claim 6  comprising wherein splitting comprises splitting the input signal into at least two beam paths with a polarization beam splitter. 
     
     
         14 . The method of  claim 13  comprising changing the state of polarization of the input signal prior to splitting the input signal with the polarization beam splitter. 
     
     
         15 . The method of  claim 6  comprising refraining from subjecting one of the first and second signals to any substantial spectral dispersion. 
     
     
         16 . The method of  claim 6  wherein subjecting one of the first and second signals to spectral dispersion comprises compressing pulses of the one of the first and second signals. 
     
     
         17 . The method of  claim 6  wherein subjecting one of the first and second signals to spectral dispersion comprises stretching pulses of one of the signals. 
     
     
         18 . The method of  claim 6  wherein the surge pulse portion comprises a substantially different state of polarization than a state of polarization comprised by the base pulse portion. 
     
     
         19 . The method of  claim 6  wherein the state of polarization of the surge pulse portion is substantially the same as the state of polarization of the base pulse portion.