AbstractThree pulse photon echoes are studied when the prevailing inhomogeneous damping arises from the application of an inhomogeneous Stark field. Whereas the molecular free flight through the inhomogeneous Stark field entails a strong attenuation of conventional photon echoes, this effect is shown to be eliminated for the even numbered echoes of a Carr Purcell sequence. These predictions are well supported by a detailed experimental study at a 3 mm wavelength. Velocity changing collision influence is discussed and T1 and T2 relaxation times of the (J, |KM| = 1,1 → 2,1) rotational transition of CH3F are incidentally determined.