在射线检测的暗袋表面加装少量磷光物质,则在暗袋曝光过程中,磷光物质吸收高能射线,其电子受到激发会跃迁至不稳定的高能态,在退激的过程中会持续释放可见光。通过在黑暗状态下观察磷光物质是否发光来判断该暗袋是否已使用过,从而避免对已使用过的暗袋进行重复曝光,节省了胶片和工时。

A small amount of phosphorescent powder was added to the camera bag′s surface,and then the phosphorescent powder began to absorb high-energy rays during the exposure process. In the exposure process,electrons would be excited to a higher unstable energy state,and should continue to release visible light in the subsequent de-excitation process. People could distinguish whether the camera bag was exposed or not by observing the visible light in dark state,thus double-exposure could be avoided effectively,saving both films and man-hours. This low-cost method is simple,convenient,and worth spreading.