ULTRAFAST TIME-TO-SPACE CONVERSION OF PHASE BY THE METHOD OF SPECTRALNONLINEAR OPTICS

We propose a method for direct conversion of an ultrashort pulse into a monochromatic beam whose wave front either repeats or is related to the phase structure of the pulse or its spectrum. This can be done by sum-frequency generation of the spectrally resolved pulses. Experiment ally, we projected two spectra of the same chirped pulse onto the nonl inear crystal so that the dispersions were opposite. After sum-frequen cy generation, a converging or diverging monochromatic beam was formed that was the analog of the pulse spectrum. We could determine the chi rp value by the measurement of the wave-front radius. (C) 1996 Optical Society of America