The document provides an overview of data storage devices, specifically CDs, DVDs, HD-DVDs, and Blu-ray discs, including their history, manufacturing processes, and types. It compares the capacities and specifications of CDs and DVDs, highlighting differences such as data transfer rates and storage limits. Additionally, it discusses competing next-generation formats, HD-DVD and Blu-ray, noting their capacity differences and market penetration as of September 2008.

1. Data Storage Device
CD & DVD
Prepared By:-
Jerin Chacko
Vyas Pratik
AP

2. Index
• History
• Manufacturing
• Types
• Difference between CD & DVD
• Limits the Data on a CD/DVD
• HD-DVD v/s Blue Ray DVD

3.  History
• First public demonstration of CD is in 1976 By Sony.
• High Quality Audio CDs have been commercially
available from October 1982 By Philips
• The VCD standard was created in 1993 by Sony, Philips,
Matsushita.

4.  MANUFACTURING OF CD/DVD

5.  Types
• CD (Compact Disc)
• DVD (Digital Video Disc)
• HD-DVD (High Defination – Digital Video Disc)
• BD (Blue ray Disc)

6. • CD
 12 cm disk with plastics substrate, aluminum coating
and plastic cover
 0.83 micron wide pits, 1.6 micron spacing
 Data storage capacity 700 MB

7.  Overall CD

8. • DVD
 12 cm disk with plastics substrate, aluminum coating
and plastic cover
 0.4 micron wide pits, 1.2 micron spacing
 Data storage capacity 4.7 GB
 Two sided, 2 levels/side top level partially reflecting
 Increase to 8.5 GB (2 sided), 17 GB (2 levels, 2 sided)

9.  Two levels of DVD

10.  Diffrence
CD DVD
Capacity: 700 MB Capacity: 4.7 GB
Data Tran. Rate: 1.4-1.6
MB/Sec
Data Tran. Rate: 11 MB/Sec
Pits Length: 0.83 Micron Pits Length: 0.4 Micron
Distance b/w Disc Sur.-Data
Sur: 1.1mm
Distance b/w Disc Sur.-Data
Sur: 0.6mm
Disc Thickness: 1.2 mm Disc Thickness: 1.2 mm

11. Note:-
This is the Optic
which help to write data
on CD/DVD

12. Limits the Data on a CD/DVD
 Each pit is one “bit” (0 or 1) of data
 How fast the CD turns (1.4 m/sec for single speed)
 Rotation speed limit: about 52x (72.8 m/sec)
 Problem is lifetime of Blue laser approaching
1000 hrs

13.  HD-DVD v/s Blue Ray DVD
• Next generation DVD format has two competitors
• HD-DVD: Toshiba, NEC, Microsoft, entertainment industry
• Blue Ray (BD): Sony, Hatachi, Panisonic, Apple etc
• Blue Ray higher capacity (25 GB) vs HD (15 GB)
• Hence shorter pits: Blue ray 0.16 μm, HD 0.205 μm
• Problem is that Blue ray is much nearer the surface (0.1 mm)
• Blue ray can have 8 layers, up to 200 GB, HD 4 layers, 60 GB
• Sept 2008 Blue ray only 8% of market, DVD 92%

15. REFERENCE SITES:-
WWW.WIKIPEDIA.ORG
WWW.DIGICOM.COM

16. THANK YOU….