Sony Blu-ray notebook reviewed

What’s the difference between Blu-ray and the traditional CD and DVD formats? First, it employs a laser, which is in fact blue-violet rather than exactly blue, with a wavelength of 405nm whereas CD and DVD formats use red lasers with wavelengths of 780nm and 650nm, respectively. Blu-ray makes use of different data reading and processing algorithms than those employed in the DVD, and they provide for a high flexibility of the physical structure of the medium. A pit can be 138, 149 or 160nm deep, so the resulting capacity of a single-layer recordable disc is up to 27 gigabytes. Dual-layer discs with a capacity of 50GB have been released, too, and this is not the limit since Blu-ray disc manufactures are willing to introduce multi-layer media with capacities up to 200GB. That’s impressive indeed, isn’t it? Blu-ray comes in three flavors: BD-ROM (read-only media for distribution of movies, games and other data), BD-R (recordable media) and BD-RE (rewritable).