The heavy ion linear accelerator of the Institut de Physique Nucléaire has been used to study the influence of the projectile charge state q i on secondary ion emission. Ions of Ne, Ar or Kr with a velocity of 1.16 MeV/u bombarded thin films of organic and inorganic solids. The experimental arrangement is described. The ion emission yield is strongly dependent on the charge state of the incident ion qi and of its atomic number (nature of the projectile). The emission yield between the three types of projectiles varies as q4eq where q eq is the equilibrium charge state within the material for each projectile