In this work we present a method of the ellipsometric control for optical filter deposition. This control procedure uses the length of the real time ellipsometric trajectory as a control parameter with respect to the length of precalculated target trajectory. This control method has been adapted for substrates whose optical structure cannot be adequately modeled. In this case an effective refractive index and absorption coefficient is assigned to the substrate, which is determined by computing the length of the experimental trajectory from the deposition of a reference layer. This effective refractive index is used to compute the target trajectory. The control procedure has been applied to the deposition of a graded index antireflection coating on Coming and float glass by plasma enhanced chemical vapor deposition. Spectrophotometry transmission measurements show the high efficiency of the control method with respect to uncontrolled filter deposition.