Abstract: The subject of the invention is a transparent substrate, especially made of glass, provided on at least one of its faces with a layer based on an at least partially oxidized silicon derivative chosen from silicon dioxide or silicon oxides which are substoichiometric in terms of oxygen, silicon oxycarbide or silicon oxynitride, and having a hydrophilic character.

Abstract: The subject of the invention is an electrically controllable system having variable light scattering and/or transmission, comprising a functional film (1, 21) provided with electrically conducting layers (2, 3, 22, 23), the said film having active elements in the form of polarizing particles, or of liquid crystals associated with dichroic dyes, and in suspension in a medium. The said system is provided with one or more means preventing/compensating for degradation by photoreduction of at least some of the active elements, especially degradation of the dichroic dyes and/or that of the polarizing particles.