| 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. |
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| 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.