Difference between Blu-ray and DVD

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Blu-ray: 

Among various optical storage devices, Blu-ray Disc with its high definition (HD) capability holds a bigger space for storing. Previous technology of DVD disc had limitations in terms of storage capacity. The Blu ray technology name comes from the smaller wavelength laser in the blue-violet region of light. Because of this smaller laser, it is possible to store information with less gap between the tracks and the optical device. It generates tighter focus, less distortion Associate in smaller pits (and tracks) as an outcome of putting the optical device nearer to the disk. the maximum space for storing of Blu-ray is 25 GB on one side. The Blu-ray name is originated by adding blue and optical “ray” and this as a result of it uses blue-violet optical device rather than a red laser optical device. because the blue laser’s wavelength is shorter, which helps for achieving the higher bit density.

DVD: 

DVD (Digital Versatile Disc) renders videos with wonderful image quality and random

access. A videodisc is constructed from a similar material because the CD however the

method and therefore the layers area unit completely different, it’s used from each of the

edges like 2 CDs area unit projected along. In DVD, RS-PC and EFMplus are used as the

error correction codes. 

Let’s see that the difference b/w DVD and Blu-ray: 

​S.NO	Blu-ray	DVD
01	The single layer size of Blu-ray is 25 GB.	The single layer size of DVD is 4.7 GB.
02	In Blu-ray, the recording or metal layer is situated closer to the reading mechanism’s objective lens.	The recording or metal layer is situated in middle of disk.
03	There are double layers of pits in blu-ray.	There are also double layers of pits in DVD.
04	In blu-ray, there is 0.30 micrometer space between the spiral’s loops.	There is 0.74 micrometer space between the spiral’s loops.
05	It holds the 0.15 micrometer space between the pits.	It holds the 0.4 micrometer space between the pits.
06	In blu-ray, picket code is used as the correction code.	In DVD, RS-PC and EFMplus are used as the error correction codes.
07	In Blu-ray, the wavelength of laser in 405 nm.	In DVD, the wavelength of laser is 650 nm.
08	In Blu-ray, the data transfer rate is 36 Mb/sec.	In DVD, the data transfer rate is 11 Mb/sec.
09	​The double layer size of Blu-ray is 50 GB.	The double layer size of DVD is 8.5 GB.
10	The numeric aperture of blu-ray is 0.8.	The numeric aperture of DVD is 0.6.
11	The thickness of blu-ray is 1.1 mm.	The thickness of DVD is 0.6 mm.
12	It is used for storing large size data like shooting videos.	It is used for storing small size data like movies after release.
13	The cost of Blu-ray disc is high in comparison to DVD.	The cost of DVD is lower than Blu-ray disc.
14	The available video codecs of Blu-ray disc are MPEG-2, MPEG-4 and SMPTE VC-1.	The available video codecs of DVD is MPEG-2.