Front filter for self-illuminating picture screen

摘要

A self-illuminating picture screen front filter consists of a glass pane (1) having a dielectric anti-reflection coating (4a-c) on its front face and an electrically conductive metal-based absorption coating (2) on its rear face, the novelty being the provision, between the glass surface and the absorption coating (2), of a medium refractive index oxide layer (3a) and then a high refractive index electrically conductive oxide layer (3b). Preferably, the medium refractive index oxide layer (3a) has a refractive index of 1.5-1.7 and consists of a mixture of SiO2 with SnO2:F, SnO2:Sb and/or ITO, while the high refractive index electrically conductive oxide layer (3b) has a refractive index of 1.8-2.2 and consists of SnO2:F, SnO2:Sb and/or ITO.