Photochromic optical article having a mirror coating

Abstract

The invention relates to an optical article comprising at least: (a) a substrate having a front main face and with a rear main face: (b) at least one photochromic compound that is able to undergo a transformation from one state, defined as “deactivated state” to another state, defined as “activated state” in response to predetermined wavelengths of the electromagnetic spectrum, (c) coated directly or indirectly onto the front face of said substrate (a), a mirror coating, said mirror coating—comprising at least two layers having a low refractive index which is lower than 1.55, defined as “LI layer”, and at least two layers having a high refractive index which is equal to or higher than 1.55, defined as “HI layer”,—and having a mean light reflection factor for wavelengths ranging into said predetermined wavelengths of the electromagnetic spectrum, defined as Rm(predetermined spectrum) that is lower than or equal to 1.0%, for an angle of incidence of 15°; a mean light reflection factor in the visible region Rv that is lower than or equal to 10.0% for an angle of incidence of 15°; and an optical robustness corresponding to the standard deviation of said mean light reflection factor in the visible region Rv, defined as “σRv” that is lower than or equal to 0.7% for an angle of incidence of 15°.

Dependencies are inferred from the claim text.