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With its recently launched 16x DVD+R Double Layer, Ricoh has significantly raised the standards for fast DL blank discs. At the same time this milestone has once again revealed the company’s high level of technical competency in the field of innovative high-speed media development. This is confirmed by the certificate issued by the Verification Laboratories Group which sets the official standards for the new Double Layer DVD+R media with write speeds of up to 16x. Delivery of the first samples for hardware manufacturers started on 7th March 2007.
The market for DVD+R double layer blank discs more than doubled last year and the boom in demand has continued unabated. Compared with single layer discs, however, double layer media have hitherto required considerable time to write their large volume of storage space. With the development of the first 16x DVD+R DL Ricoh has now radically increased writing speed while at the same time significantly reducing the writing time for the medium. This technological innovation once again confirms Ricoh’s position at the forefront of the development of high-precision double layer production technologies.
The “Inverted Stack Method” invented by Ricoh is already regarded as the best possible technique for the attainment of high recording speeds in high-precision DVD+R DL media production. This Ricoh production method differs considerably from the “2P method” in which all layers are stacked on a single substrate. Separate production of both recording layers as practised by Ricoh, initially takes place separately on both substrates. The two components are then pressed together. Thus in practice Ricoh’s “Inverted Stack Method” provides increased precision for both recording layers.
To ensure the high writing speed of 16x for the DVD, the medium must have exceptional mechanical properties. Thus the extremely precise groove formation of the Ricoh blank disc not only has a decisive influence on correct tracking but it also serves to completely avoid distortion. However not only were improvements made to eccentricity and production tool precision but newly developed recording materials were also deployed.