A Blu-ray disc (BD) is a type of optical disc that was designed for the storage of high-definition video and huge data compared to a standard DVD.
It gets its name Blu from the blue-violet laser light that it uses to read and write data. The blu laser light allows for high-capacity storage and better quality than the red light used on the DVD.
The disc format was developed by a group of companies that produce optical discs. The group is known as Blu-ray Disc Association which includes leading companies in the optical disc industry such as Sony, Samsung, Philips, and Panasonic.
A standard single-layer blu ray disc has a capacity of 25 GB while a double-layer can go up to 50GB of storage.
Characteristics of Blu-ray disc
To be able to store that huge and high-quality data within the same size as a DVD the disc has unique features. These features help to fit more in small spaces among others. Below we discuss some of these characteristics.
- Use of blue-violent laser light: blue laser light has a short wavelength that increases the precision of where data is written and read. This means more data can be packaged in a smaller space. This enables the disk to carry more data.
- It uses Advanced Access Content System (AACS) data protection that restricts the copying of data in the disc and still maintains high quality.
- Offer menus and more interactivity: BD offers users some menus and allows them to interact with the content on the disc when it is playing.
- High storage capacity for high-definition video: A single-layer BD can hold media of up to 25GB, while a dual-layer can take 50 GB. However, we have some that can take over 100GB of data.
Blu-ray discs are used for different functions and in different areas. In each of the areas they are used since they offer benefits to the user on how data is stored and accessed the following are some of the areas where Blu-ray discs are used.
- Video and movie production: this is the main consumer of Blu-ray discs. They use discs to store high-definition movies format such as 4K which has high resolution. The movies can also include behind-the-scenes footage, subtitle, and multiple audio among other features.
- High-definition resolution gaming: Advanced games use high-resolution graphics that take up a lot of storage space. BD offers support for both high-definition footage of the game and the capacity to store the same. This makes Blu-ray ideal for game storage. Most PlayStation comes with a Blu-ray player
- Home and personal entertainment: at a personal level users can buy a Blu-ray player that they can use to watch movies that are high definition. BD also supports the latest type of 3D movies.
- Data backup: the disc can be used in all areas and industries to keep a backup of huge multimedia data. The data can include video, photos, audio, documents, or any other type of file the organization needs to back up. They are used as secondary storage devices for backup.
- Security agencies: military, police, and other security firms use the disc to store video footage collected from CCTVs or other severance systems. The BD stores more data and ensures the quality is maintained. The footage captured using drones can also be stored in the blu ray disc.
- Medical imaging: most of the medical imaging today is done using digital machines. Blu-ray can be used to store and share this data which can be huge and require high-quality resolution. The data can be from X-rays, MRI images, and cancer scan machines among other data produced in a hospital.
- Libraries, museums, and national archives: institutions that are tasked with the responsibility of keeping organization or country data can use the disk for storage. The disc can be used to store all kinds of data from books, publications, national event footage, and history recording among others for save keeping.
Advantages of Blu-ray discs
- High storage capacity: a single-layer Blu-ray can hold up to 25GB of data, while a dual-layer can go up to 50 GB. This is more than 5 times what a standard DVD of 4.5GB can hold. We also have a triple-layer BD that will be able to hold almost 100GB of data.
- Blu-ray disc players support backward compatibility. This means if you have a player it can read and write on CD and DVD. however, if you have a CD or DVD player they cannot read a Blu-ray disc.
- BD discs are more durable than DVDs and CD. the disk is less likely t be damaged by scratching compared to the old optic discs.
- It supports High-Definition (HD) video: Blu-ray disc is capable of storing and playing high-definition video with a resolution of 1080p. It also supports high-quality audio format media which when combined offers a better movie experience.
- Blu-ray offers more advanced features such as menus and live interactivity. Use can access the menus when the disc is playing which is not possible with DVDs.
Disadvantages of Blu-ray disc
- Compared to other optical disc storage devices blu-rays are more expensive. The drive that can read and write on the disc is also more expensive than the CD/DVD writer.
- BD disc has not been widely adopted. It is mostly used by video and movie producers. Most standard users don’t use the disc.
- Those who like making copies of other people’s work, may not like the disc that is copy protection.
- To read or write a Blu-ray disc you need to buy a disc writer since the old CD/DVD write are not compatible.
- While Blu-ray discs are more durable than DVDs, they can still be scratched or damaged if not handled properly.
Types of Blu-ray disk
BD discs can be classified into 2 main types according to the number of time data is written on them.
- BD-R: this is Blu-ray recordable. It can be written only once but read many times. These are mostly used to package movies and software that don’t require editing. They can be a single or dual layer which determines the capacity of the disc.
- BD-RE: they allow users to write and read many times. The discs are equivalent to DVD-RW. BD-RE can be erased and recorded many times. Just like the BD-R, they can be single or dual layers.
- BD-XL: this means extra large storage capacity. The disc can either be BD-R or BD-RE which has more than 2 layers that support over 100GB of data. Some have triple or four layers of storage.
Difference between Blu-ray and DVD
The main difference between Blu-ray and DVD is the storage capacity and the laser light that is used to read and write data. Other differences are the cost and quality of media they can support. The table below summarizes the difference between the two discs.
|Storage capacity||Single layer has 25GB capacity while we can have over 100GB with triple layer disc||The DVD has a capacity of 4.7GB|
|Media quality||It supports high-quality video and audio formats. It allows 4K and high definition videos storage||It only supports low to media-quality of videos.|
|Cost||They are relatively expensive compared to DVD||They are cheaper than the Bluy-ray|
|Interactivity||It allows users to interact with the disc while it is playing. It also offers menus.||DVDs don’t support live user interaction.|
|Compatibility||The Blu-ray drive can be used to read and write the CD and DVD||A CD/DVD drive cannot read or write Blu-ray disc|
|Type of laser used||It uses blue-violent laser light which has a short wavelength||Uses red laser light which has a long wavelength|