A helical TEA‐CO2laser was mode locked by inserting a positive germanium plate close to the plane mirror of a hemiconfocal type of resonator. Single pulses of the emitted sequence of nanosecond spikes were recorded with high time resolution. Best fitting the experimental curves to a Gaussian and (cosh)−2time dependence revealed that the temporal pulse shape corresponds with great accuracy to the (cosh)−2behavior as it is predicted in a theoretical treatment of Haus. Since this theory is dealing primarily with steady‐state saturable absorber mode locking, it is also pointed out that it can be applied to the above case.