A new type of Blu-Ray digital video disk made largely from paper has been developed by Sony and Toppan Printing in Japan. The two companies say such paper-based disks will be cheaper to make and less environmentally harmful.
Blu-Ray disks, considered a successor to conventional DVDs, store data using a blue laser rather than a regular red one. Because the wavelength of the blue laser is smaller, more information can be read from this type of disk.
Data is stored on Blu-Ray disks in the form of tiny ridges on the surface of an opaque 1.1-millimetre-thick substrate. This lies beneath a transparent 0.1mm protective layer.
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