Stimulable phosphor sheet stacking tray

A stacking tray for stacking stimulatable phosphor sheets one by one in parallel with an inner wall facing an opening face of said stacking tray, said stacking tray comprising:

• tray member having an inner wall adapted to support a plurality of parallel sheets in a stacked relationship;
• and
• sheet fall preventing means for preventing sheets from falling outwardly of said opening face when said tray member is disposed at such a position that the sheets inside of said stacking tray stand erect, said sheet fall preventing means being movable between a stop position and a retracted position relative to said tray member, said sheet fall preventing means comprising:
• a stopper selectively movable between said stop position and said retracted position which correspond to movement of said stopper inwardly and outwardly, respectively, of a side of said opening face, wherein in said stop position said stopper permits removal of the sheets by an external pulling action, said stopper projects into an interior region of said tray member at an intermediate position of said side of said opening face and remains a predetermined and constant distance away from said inner wall regardless of the presence or amount of sheets, and said stopper contacts of sheets when the sheets stand erect;
• means for projecting said stopper into said interior region;
• and
• supporting means for supporting said stopper for selective movement between said stop position and said retracted position.