Blu-Ray is a format of DVD designed for the
storage of high definition video and data.
Logo of blue ray.
Blu-ray disc is a digital optical disc data
storage format. It has been created to supersede the DVD format. It is a
third-generation optical disc. Blu-ray is capable of storing hours of video in
high definition and ultra-high definition resolution. It was developed by Blu-ray
Disc Association. This is same size as
DVD. The name Blu-ray refers to blue laser as it has less wavelength than red
laser as in DVD specifically and the laser used to read the disc. It acts as
medium for featured films, physical distribution of video games for the play
station 3, play station 4, Will U and Xbox one. Standard Blu-ray disc can hold
over five times the data that a DVD can hold. It has capacity to support lots
of audio formats like DOLLBY and dtsHD which offers incredible sound quality. Blu-ray
disc can store HD videos of up to 2160p resolution and 60 frames per second.
Fig. Cross section of Blu-ray disc.
Optical disc has a layer
where pits and flats contain the disc data in simple binary format, a pit
represent 0, whereas the flat area represents 1. A laser light points on the
disc as it spins and when the laser light hits the flat area, it reflects to
photoelectric cell which then detects the light. The same a laser light hits
the pit, it doesn’t reflect light to photoelectric cell. This way photoelectric
cell interacts with the laser light as binary data. These binary data are
processed for a data, a movie or a music. The data storage in an optical disc
is depends on how small the pits can be made on the physical layer and also the
type of laser been used. For instance, Blu-ray used blue laser which has the
smaller wavelength (405nm) where DVD uses red laser (wavelength- 650nm) and CD
uses infrared laser (wavelength- 780nm). Because of the smaller wavelength of
the Blu-ray, became more precise and more data can be stored on the service
area which is approximately 5 times the DVD. The blue laser reads the info and
makes the waves shorter than regular red laser. The shorter waves move faster
and allows the disc to have to more space.
Fig. Laser interaction on
blue ray disc.
laser will scan all the data that is to be played on the TV or electronic
device by a wave. It also has the info about the encrypted disc where encrypted
data is to ensure that it is against piracy and lets the player to decrypt the
data. Then the disc starts spinning in the player allowing it to convert a
digital video and audio information and then goes to TV monitor or the device
connected to the Blu-ray player through HD connector cable or separated
compound cable connection.
Blu-ray discs are present in two layers:
single layer and double layer. The information stored in Blu-ray are very small
in size and is about 0.15 x 10 – 6 meters long, hence single layer BD is more
efficient to hold 25GB of data. Data will be in the poly-carbonate which is 1mm
thick and it stops the birefringence and causes no distortion for reading the
data. It has a outside hard cover to prevent scratching and finger prints.
TYPES OF BLU-RAY DISC:
BD-ROM (Read Only Memory Blu-ray
disc) – can only be read but cannot be written over.
BD-R (Recordable Blu-ray disc)
– mainly used to store PC data.
BD-RW (Re-writeable Blu-ray disc)
– used to store PC data and contents can
be written over and over.
BD-RE (Re-writable Blu-ray disc)
– mainly used for store data used in HDTV and can be written again and again.
Fig. Blu-ray disc. Fig. Blu-ray player.
wavelength makes it move faster and gives crisp awesome detailing in the movie.
provides disc to have more room, not only for movies but may be for more bonus
of holding 50 GB of data where as DVD can hold up to 4.7 GB.
playback and burning speed.
supports 7.1 channels of uncompressed audio.
to make our own playlist.
programs present on the disc can be re-ordered in any way as u like.
Very expensive technology.
High definition capacity is not a
substantial amount even though storage space is more.
Blu-ray may be nullified because consumers
settle for the less expensive competitor because of increase in the popularity
of HD DVD players.
Not only the technology is expensive but
also the Blu-ray discs have a high price tag.
Thank You **