The invention relates to a glass substrate (10) comprising a first surface (11) and a second surface (12) that is opposite the first surface, said substrate (10) comprising, on top of the second surface thereof, an electrode coating (5) that comprises at least one electrically conductive layer, characterized in that said glass substrate (10) comprises, between the second surface (12) thereof and the electrode coating (5), at least one glass material layer (3) having an index between 1.7 and 2.4 inclusive and containing bismuth oxide Bi2O3 between 40 and 60 wt% inclusive, or even between 45 and 58 wt% inclusive, and moreover containing ZnO between 5 and 30 wt% inclusive and preferably between 10 and 25 wt% inclusive.