Temporal evolution of the laser electric field at any point of the tra
nsverse plane of a bimode CO2 laser is reconstructed using three fast
detectors located at different points in the transverse plane. We inve
stigated a situation in which the dynamics is particularly rich i.e. d
isplaying different periodic and chaotic regimes. A comparison between
numerical analysis and experiments allows us to perform a critical ev
aluation of the method.