How reliable are FROG and GRENOUILLE?
FROG is rigorous, general, and relatively simple to implement, and it has become a very successful technique, with many accomplishments. The shortest pulse ever generated at the time of this writing (4.0 fs) was measured using FROG. Indeed, autocorrelation measurements (interferometric or otherwise) are no longer acceptable to claim a world s record short pulse. GRENOUILLE is a simplified version of FROG and has similar performance, although it can t be used for pulses shorter than ~10 fs. Fortunately, Swamp Optics will soon offer a FROG for measuring pulses as short as 10 fs.
