Blu-ray discs have several advantages over traditional DVDs including significantly higher storage capacity of 25GB for a single-layer disc and 50GB for a dual-layer disc. Blu-ray uses a blue-violet laser with a shorter wavelength than DVDs, allowing it to store more data in the same space. Blu-ray discs also have a durable hard coating that provides strong resistance to fingerprints, marks, scratches and dust. The Blu-ray format was developed by the Blu-ray Disc Association and emerged victorious in its format war with HD DVD.

1. Done By: Yogesh Kumar Goyal

2. Inside this Article foundation Disc Characteristics Advantages Basic Formats Techanology D

3. Foundation The Name The blu-ray name is a combination of “blue”, for the color of the laser that is used and “ray” for optical ray. The “e” in “blue” was purposefully left off, according to the manufacturers, because an everyday word cannot be a trademark.

4. Foundation Blu-Ray The first blue laser was developed in 1996 by Shuji Nakamura (Nichia Corporation) In 2002, an alliance was formed, called the Blu-ray Disc Association, including the likes of Sony, Samsung, Sharp, Hewlett-Packard, and Royal Phillips

5. Disc Characteristics Diameter: 120 mm Thickness: 1.2 mm Center hole diameter: 15 mm Uses GaN laser of wavelength 400 nm The smaller laser, compared to the DVD and CD, keeps the process more efficient (~5 mW)

6. Storage Capacity A single-layer Blu-ray disc has storage capacity 25GB A dual-layer BD can hold data up to 50GB 5 10 Single Sided, Single-Layer Single Sided, Dual-Layer

7. Advantages Instantly skip to any spot on the disc Record one program while watching another on the disc Edit or reorder programs recorded on the disc Automatically search for an empty space on the disc

8. Advantages Blu-ray also has a higher data transfer rate - 36 Mbps than today's DVDs, which transfer at 10 Mbps Record high-definition television (HDTV) without any quality loss. Access the Web to download subtitles and other extra features. Blu-ray Discs unprecedented scratch resistance.

10. BD-R (recordable) - for PC data storage

11. BD-RW (rewritable) - for PC data storage

13. Need of blu ray technology A current, single-sided, standard DVD can hold 4.7 GB of information. That's about the size of an average two-hour, standard-definition movie with a few extra features. But a high-definition movie, which has a much clearer image, takes up about five times more bandwidth and therefore requires a disc with about five times more storage. As TV sets and movie studios make the move to high definition, consumers are going to need playback systems with a lot more storage capacity.

14. THE TECHNOLOGY Pits : spiral grooves that run from the centre of the disc to its edges Bumps : other sides of these edges. Track pitch : it is the distance between the two tracks (of pits) on the surface. -------------------------------- Disc store digitally encoded data in PITS. --------------------------------

15. THE TECHNOLOGY So, in blu-ray disc: Pit size – 0.15 microns ( more than twice as small as the pits on DVD ) Track-pitch is : 0.32 microns Laser needed : blue-violet laser (405 nm) Data transfer rate : 36 Mbps

16. Hard-coating technology In January 2004 was introduced a clear polymer coating that gives Blu-ray Discs unprecedented scratch resistance. The coating was developed by TDK Corporation and is called "Durabis". It allows BDs to be cleaned safely with only a tissue.

19. How Blu-ray Reads Data The Blu-ray disc overcomes DVD-reading issues by placing the data on top of a 1.1-mm-thick polycarbonate layer. Having the data on top prevents birefringence and therefore prevents readability problems. And, with the recording layer sitting closer to the objective lens of the reading mechanism, the problem of disc tilt is virtually eliminated. Because the data is closer to the surface, a hard coating is placed on the outside of the disc to protect it from scratches and fingerprints.

20. Laser and optics or physics Blu-ray systems use a blue-violet laser operating at a wavelength of 405 nm, similar to the one used for HD DVD, to read and write data. Conventional DVDs and CDs use red and infrared lasers at 650 nm and 780 nm respectively.

22. More Industry Support/Consumer Reach (BDA has 140+ members)

23. More Durable

24. More Interactive User Experience

26. Blu-ray Technology Cont. Data capacity Because Blu-ray uses a blue laser(405 nanometers) instead of a red laser(650 nanometers) this allows the data tracks on the disc to be very compact. This allows for more than twice as small pits as on a DVD.

27. Blu-ray Technology Cont. Data Capacity Cont. Because of the greatly compact data Blu-ray can hold almost 5 times more data than a single layer DVD. Close to 25 GB! Just like a DVD Blu-ray can also be recorded in Dual-Layer format. This allows the disk to hold up to 50 GB!! Because the polycarbonate layer of the Blu-ray disc is so much larger than a DVD because the recording layer is so much smaller it can have even more than two layers.

28. Blu-ray Technology Cont. Writing Data Blu-ray uses a combination of two lenses to greatly shrink the laser to read the data. This also allows for higher data rate transfer close to 36 mbps. It could record 25 GB of data in an hour an a half.

29. Description of Blu-ray Based on phenomenon that using lasers with shorter wavelengths would enable optical storage with higher density Practically, this is done by decreasing the wavelength, increasing the numerical aperture from 0.60 to 0.85 and making the cover layer thinner to avoid unwanted optical effects. This allows more information to be stored in the same area.

30. Description of Blu-ray (Cont) Standard single-disc size is 25GB compared to DVD’s 4.7GB More scratch-resistant compared to DVDs Forced in part due to Blu-ray’s data layer being closer to the surface of the disc.

31. History of Blu-ray First prototype unveiled at the CEATEC exhibition in Oct 2000 First consumer devices released in Apr 2003 First titles released in June 2006 Toshiba ended support for HD DVD in Feb 2008, effectively ceding format wars to Blu-ray

32. Positive Aspects about Blu-ray More data can be stored into fewer discs. Higher quality movies Incorporated copy protection technology may allow companies to lower costs of discs due to decreased chance of piracy

33. What are Blu-ray Discs?

34. Background Information 1998 – Release of High-Definition Televisions Shuji Nakamura Invents blue LED technology but kept off market due to patent problems The first DVR Blue prototypes unveiled at the CEATEC exhibition in October 2000 The DVD Forum deeply split over whether to develop blue laser technology because of its higher expense. Sony includes blu-ray players in PlayStation3 – although HD DVD head starts in the high-definition video market, this changed the game By February 2008, Toshiba withdrew its support for the HD DVD format, leaving Blu-ray the victor

35. Red Laservs. Blue Laser

36. Benefits of Blu-ray Discs Significantly increased storage space (50GB vs. today's 4.7GB) Has the potential to store 500GB on multiple layers Has the potential of up to 54MB/s read and write speeds Allows for high definition 1080p movies to be marketed

37. Criticisms Critics say Sony is more concerned with royalties than creating the best technology for the consumer Manufacturing Blu-Ray discs requires new machinery, while alternatives like HD-DVD can be produced on existing DVD equipment In the interest of copy-protection, companies have included over-protective DRM that has caused some consumers to experience problems playing purchased discs in their players Bill Gates: “the protection scheme under Blu-ray is very anti-consumer”

40. On GAURD Blu-ray discs are better armed than current DVD’s. They come equipped with a secure encryption system– a unique ID that protects against video piracy and copyright infringement.

43. Instantly skip to any spot on disc

44. Record one program while watching other on the disc

45. Create playlists

46. Edit or reorder programs recorded on disc

47. Automatically search for an empty space on the disc to avoid recording over a program

48. Access to web to download subtitles and other extra features

52. ADVANTAGES It can store 25 GB of data on each layer 50 GB on dual layer disc There is about 9 hours of high definition video on a dual layer Blu-ray disc It can store 30% more capacity than HD-DVD

53. DISADVANTAGES Discs are more costly to produce than HD-DVDs The cheapest Blu-ray players run about 500-600 dollars at this time and cheaper players such as the Samsung BD-P100 has been getting very mixed reviews Discs are still distributed by regions

54. FUTURE TDK (Tokyo Denkikagaku Kogyo Corporation) recently announced that they have created a working Blu-ray disc capable of holding 200GB of data (six 33GB data layers).

55. Compatibility This issue has introduced a competitor, the HD-DVD, that based its technology around being compatible with the DVD Recently the BDA has developed recorders that are BD/DVD/CD compatible JVC has advanced the BD by developing a BD/DVD combo disc that stores both DVD and BD data. It is composed of two DVD layers and a third BD layer storing 33.5 GB total

57. Variations and Sizes A single-layer Blu-ray disc (BD) has enough storage capacity (25GB) for approximately two hours of high-definition video with audio. A dual-layer (50GB) BD can hold enough data for approximately four hours of HD video. TDK recently announced that they have created a working Blu-ray disc capable of holding 200GB of data (six 33GB data layers).

58. Disc Characteristics Single layer: 25 GBDual layer: 50 GB Diameter: 120 mm Thickness: 1.2 mm Center hole diameter: 15 mm Uses GaN laser of wavelength 400 nm The smaller laser, compared to the DVD and CD, keeps the process more efficient (~5 mW)

60. automatically search for an empty space on the disc to avoid recording over a program.

62. Blu-ray discs only do the injection-molding process on a single 1.1-mm disc, which reduces cost. That savings balances out the cost of adding the protective layer, so the end price is no more than the price of a regular DVD. Blu-ray also has a higher data transfer rate -- 36 Mbps (megabits per second) -- than today's DVDs, which transfer at 10 Mbps. A Blu-ray disc can record 25 GB of material in just over an hour and a half.

63. Future Expect the BD to become more prevalent once the HDTV market establishes its presence Audio and video will reach higher qualities with larger storage space Look for BD with more than two layers as the technology is further refined

66. Can hold data up to 25/27 GB that means 2 hrs of HD video or about 13 hrs of standard video.

67. DOUBLE LAYER :