Method for treating a mirrored optical item

Abstract

The invention relates to a method for treating a mirrored optical item, comprising: a substrate (), a mirroring stack () of at least two interference layers (Mto M) carried by the substrate (), thus increasing the reflection and having: an interference layer (M) distant from the substrate (), with a first initial thickness and a first refractive index and at least one near interference layer (M) arranged between the substrate () and the distant interference layer (M), with a second thickness and a second refractive index different from the first refractive index, the mirroring stack () giving the mirrored optical ilem () a first colouring according to the CIELAB space, by means of an interferometry phenomenon, the method comprising a step () of removing, by ion bombardment, at least in one first predetemrined zone (Z), a thickness of the mirrored stack that is less than the sum of the initial thicknesses concerned by the removal step, the mirrored optical item having, by means of an interferometry phenomenon, a second colouring according to the CIELAB space different from the first colouring.