Compact discs are over 30 years old and as likely to be used as a Metallica desk clock as a way to cue up Master Of Puppets. But it turns out that we may not have even come close to reaching the capacity of optical storage mediums.
Instead of the 4.7 gigabytes of data a DVD holds, or 700 megabytes a CD currently holds, Dr. Zongsong Gan and his team at Australia’s Swinburne University of Technology have figured out how to store 1,000 terabytes of data on a single DVD, and were recently awarded a Victoria Fellowship for the work.
The current limitations of writing data to optical discs is what’s known as the refraction limit of light. Since light can’t be broken down smaller than 500 nanometers, it was assumed that lasers (light) couldn’t write bits of information smaller than 500 nanometers either. That’s apparently not true, as Dr. Gan and his partners figured out that using two light beams, they can shorten the writing light down to just 9 nanometers.
This is the difference between drawing on a piece of paper with a huge Sharpie and a fine-tip pen. The fat maker can’t include the same amount information and drawing details that the pen with a small tip can–same for the beam of light writing bits to a disc.
Cleverly, the reachers used two light beams, both 500 nanometers themselves. One was used for writing bits of information while the second purple circular beam was used to block all but a point of light 9 nanometers in width.
The benefits of this technological advancement are pretty obvious, like being able to put higher resolution video on a single disc. But there are still some serious problems these advancements raise as well.
“Putting so much information on a single disc makes it easier for people to destroy huge amounts of data and thus cost more to protect the disc,” says Dr. Gan. “Also, we are now working to speed up for data reading and recording. If we’re still using the current DVD speed, how long it will take to write 1,000 TB of data onto a disc?”
In addition to the entertainment benefits, like video sizes, Dr. Gan is also highly focused on the implications for general purpose data storage. Being able to radically increase data storage, either on optical discs or another format, will go a long way toward what the researcher imagines for the future.
“In my mind, I have an vision for our society in the future where everyone will have a data bank account just like we all have a bank account today,” Dr. Gan explains. “We’ll save all of our data in the data bank. Everyone no longer needs the same things today as phones, iPads, or laptops. We only need a soft touch screen, any data processing, while storage is done remotely.”