An apparatus (1) for erasing a storage phosphor layer (2) includes a drive (5) for producing a relative movement between the storage phosphor layer (2) and the radiation source (8), the storage phosphor layer (2) lying or being moved in a holding plane (7), and a reflector (11) for reflecting radiation. The reflector (11) is arranged and designed to reflect erasing radiation reflected by the storage phosphor layer (2) in the direction of the storage phosphor layer (2). A width (14) of the reflector (11) in the direction (6) of the relative movement is at least ten times as great as a smallest distance (15) between the reflector (11) and the holding plane (7).