“One of the big unsolved problems is the measurement of pulses that have significant temporal and spatial structure, for example, a pulse whose energy spectrum varies from point to point in the beam. Such ‘spatial chirp’ is characteristic of beams from pulse stretchers and compressors (even those that are only slightly misaligned!) used in high-power chirped-pulse amplifiers. ... The revolution that has taken place only recently in ultrashort-pulse measurement has not only yielded powerful new laser diagnostics, but also has opened up tremendous new possibilities for ultrafast science and technology.”