摘要 |
An electroluminescent laminate is provided that comprises: a planar phosphor layer (22); a front and a rear planar electrode (14,24) on either side of the phosphor layer; a planar dielectric layer, which is preferably composed of a thick layer (18) and a thin layer (20), between the rear electrode and the phosphor layer, the dielectric layer being formed from sintered ceramic material such that the dielectric layer provides a dielectric strength S which is greater than about 1.0 X 106 V/m and a dielectric constant such that the ratio of the dielectric constant of the dielectric layer to that of the phosphor layer is greater than about 50:1, the dielectric layer having a thickness sufficient to prevent dielectric breakdown during operation as determined by the equation d2 = V/S, wherein d2 is the thickness of the dielectric layer and V is the maximum applied voltage, the dielectric layer forming a surface adjacent the phosphor layer which is sufficiently smooth that the phosphor layer illuminates generally uniformly at a given excitation voltage, and wherein the dielectric layer is either in contact with the phosphor layer or spaced apart from it by at least one additional layer that is itself in contact with the phosphor layer and wherein the layer that is in contact with the phosphor layer is compatible with the phosphor layer. <IMAGE> |