Abstract: The invention relates to a discharge lamp comprising a group IIIB or rare earth monoxide radiation emitting material, which allows to greatly improve the features of the lamp due to superior light emitting properties of the monoxide compound.

Abstract: A picture display device having a vacuum envelope which is provided with a transparent face plate and a display screen having a pattern of luminescent pixels, and with a rear wall, comprising electron-producing means, an addressing system arranged between said means and the face plate so as to address desired pixels, and, adjacent to the display screen, a plate of electrically insulating material provided with apertures for passing electrons, in operation a voltage difference being applied across said plate, characterized in that the surface at the electron entrance side of the apertured plate is coated with a coating of a material selected from the group comprising nonstoichiometric nitrides, borides and carbides of Al and/or Si, and amorphous Si.