What makes FROG and GRENOUILLE better than other measurement methods?
Unlike autocorrelation, GRENOUILLE measures the complete pulse intensity and phase vs. time (and the spectrum and spectral phase) and does not require any assumptions about the pulse shape. In addition, GRENOUILLE has many additional advantages. It combines this full-information pulse measurement with much-needed experimental simplicity. It has few elements and so is inexpensive and compact. It also operates single-shot. And it is more sensitive than autocorrelators. In addition, several feedback mechanisms on the measurement accuracy that are already present in the FROG technique work with GRENOUILLE, allowing confirmation of—and confidence in—the measurement. And it measures the beam spatial profile. Even better, it measures the most common spatiotemporal pulse distortions, spatial chirp and pulse-front tilt. But best of all, GRENOUILLE is extremely simple to set up and align: it involves no beam-splitting, no beam-recombining, and no scanning of the delay, and so has zero sensitive
