BDXL

Sony is about to start selling the industry’s first 128 GB write-once BD-R XL optical media. The discs will also be the first quad-layer BDXL media formally aimed at consumers, but bringing benefits to professionals that use BDXL today. Although the general BDXL specifications were announced back in 2010 for multi-layered write-once discs with 25 GB and 33.4 GB layers, only triple-layer BDXL discs with a 100 GB capacity (generally aimed at broadcasting, medical, and document imaging industries) have been made available so far. By contrast, quad-layer 128 GB media has never seen the light of day until now. As it turns out, increasing the per-layer capacity of Blu-ray discs (BDs) to 33.4 GB via a technology called MLSE (Maximum Likelihood Sequence Estimation) was not a...