DVD Storage Capacity Reaches Impossible Level


A group at Australia’s Swinburne University of Technology led by Dr. Zongsong Gan managed to squeeze a petabyte of data on a DVD.  A petabyte is equivalent to 1000 terabytes.  A petabyte is 1,000,000,000,000,000 bytes.  You could store 40,000 HD moves in a petabyte. DVD that can hold 1 terabyte

Optical Media Capacity
  CD   700 MB - 80 minutes of music  
  DVD    4.7 GB
  Dual-Layer DVD   8.4 GB
  Blu Ray   25 GB
  Dual-Layer Blu Ray         50 GB
  Triple-Layer Blu Ray         100 GB

A CD is read by an infrared laser, a DVD is read by a red laser and a Blu Ray DVD is read by a blue laser.  It was assumed that it was impossible for a laser to write anything smaller than 500 nanometers.  The Australian team proved this wrong by writing bits that were just 9 nanometers.  They accomplished this by using 2 beams that were both 500 nanometers.  One beam was used for writing the data the other beam a purple circular beam was used to filter the first laser to a light point of 9 nanometers in width.  A nanometer is one billionth of a meter.  Wouldn’t it be nice to have all your data, pictures and videos on a single DVD?  Of course you would want to make sure that you had multiple backup copies.