A packed phosphor screen or panel consisting of at least one flat square or rectangular screen or panel, optionally packed apart in a wrapper foil, and a sealed package, wherein said package is layered in form of an asymmetrical barrier layer foil, said foil comprising an inner flexible thermoplastic polymer layer and an outer polymer layer in adhesive contact with an aluminum layer situated inbetween said inner flexible thermoplastic polymer layer and said outer polymer layer, wherein said foil is characterized by adhesive forces, between said outer polymer layer and said aluminum layer, of more than 2.5 N/mm² following DIN 53 357, by a permeation to water vapor of less than 0.01 g per sq.m. in an environment having a temperature of 23 C. and a relative humidity of 75% RV for 24 hours following DIN 53 122, and by a permeation of less than 0.01 cm³ per sq.m. per 24 hours and per bar for each of oxygen, carbon dioxide and nitrogen following DIN 53 380 (ISO 2556, ASTM D 1434).