We demonstrate a new technique for the direct, realtime, femtosecond scale
temporal measurement based on the conversion of temporal information to the
spectral domain. The potential of the method has been experimentally inves
tigated with an optical fiber spectral compressor device, first stretching
and up-chirping the pulses in a prism dispersive delay line, and afterwards
compensating the induced chirp by means of cross-phase modulation in a sin
gle-mode fiber. Spectre-temporal imaging (STI) reduces the problem of high-
resolution temporal measurements to standard spectrometry.