A system for low dose x-ray imaging provides for dynamic generation of an x-ray beam with specific shape, and dynamic tracking of a detector with said beam. The disk cartridge includes: a disk housing including a disk receiving unit for rotatably receiving a disk, and an opening portion formed at a portion corresponding to a hub of the disk and formed where a pickup unit for recordingreproducing data tofrom the disk while being rotationally moved on the disk moves; and a shutter for opening and shutting the opening portion. By utilizing the document object model and the universal content stream with a corresponding reader on the wireless device, the electronic document is reduced to only the essential content and the necessary format information for transmission.