An apparatus, a corresponding system, and a method for reading out X-ray information stored in a storage phosphor panel includes an input device, into which a cassette with a storage phosphor panel therein can be input, and a read-out device, in which the storage phosphor panel can be irradiated with stimulation light and the emission light excited in the storage phosphor panel is detected. In order to enable the cassette that has been input to be locked and/or opened as reliably as possible in conjunction with a simplified construction, at least one mechanical element which can be mechanically driven by a movement of the cassette upon the cassette being input into the input device locks and/or opens the cassette in the input device