The present invention assures a satisfactory adhesiveness of an input screen 13 of an X-ray image intensifier, high resolution of an output image and brightness uniformity as required, by configuring an aluminum or aluminum alloy substrate 21 so to have a concave surface with minute irregularities of the substrate material removed by burnishing, excepting gentle irregularities 21c without directivity which are caused by pressing. The gentle irregularities 21c of the substrate 21 preferably have an average length L in a range of 50 &mgr;m to 300 &mgr;m between the neighboring bottoms and an average height H in a range of 0.3 &mgr;m to 4.0 &mgr;m from peaks to bottoms. The invention improves resolution with light on the substrate surface suppressed from being scattered, and decreases image noises which are caused by the minute irregularities.