TDK is one of the 14 companies that make Blu-ray discs and they have announced a Blu-ray disc with 200GB of storage capacity. To be straight, it’s four time the capacity of the largest initial dual-layer Blu-ray discs. TDK's research and development efforts are achieving unprecedented capabilities for next generation optical media. The company's advanced material science played a key role in enabling the development of 200GB blue laser disc technology. The company's 100GB prototype disc uses four 25GB layers to reach 100GB capacity. For the 200GB technology development, TDK has stretched the physical margins of the Blu-ray Disc format, enabling a disc to store up to 33.3GB per layer while staying within the tolerances of the BD playback specifications. The company said it expects the discs to be made commercially available in several months.