This ‘Super DVD’ Can Hold 20 Million Photos

Close-up photo of a compact disc against a black background

Researchers have developed a new method of storing data on an optical disk. It is capable of holding 24 times the data of the most advanced hard disk drives: the equivalent of 20 million digital photos.

Update 2/29: Added information concerning BD-XL disks, which have capacities up to 128GB

The researchers have successfully developed a disk that can store 1.6 petabits. But people still think of megabytes, gigabytes, and terabytes, so what does “1.6 petabits” mean in real-world terms?

Assuming the average photo is 10MB, a reasonable enough reference point, a 1.6-petabit disk can hold 20,000,000 photos.

It’s a far cry from the early digital cameras that recorded photos to floppy disks. Some of those, like the Sony Mavica FD5, could only store a few dozen very low-res photos.

That sounds impressive enough, but consider that a dual-layer Blu-Ray disk, the largest optical disk format available to consumers, has a 50GB capacity. It’s possible to store 5,000 of these “average” photos on a Blu-Ray, which is 0.025% as many as the new 3D nanoscale optical disk.

There are also triple- and quadruple-layer BD-XL disks designed for broadcast and archival purposes with 100GB and 128GB capacities, respectively. These aren’t common consumer formats, but for completeness, the 3D nanoscale optical disk holds, 1,562 times more data than the largest Blu-Ray format.

To store as many photos on Blu-Ray disks as even this first-generation 3D nanoscale disk, a person would need 4,000 Blu-Rays — enough to make even the most ardent movie aficionado blush.

By creating an enormous storage array of many of these new 3D disks, the new research could revolutionize how the world’s data is stored and how much space and energy is required to store it.

So, How Does It Work?

Unlike a traditional optical disk like a CD, DVD, or Blu-Ray, the similarly sized “3D nanoscale optical disk” stores data across three dimensions, not two. This breakthrough is due to the team’s novel means of applying light patterns to the disk’s surface, the dye used in the film (the substrate on which data is written), and the molecules in this film that react to the light used to read data.

The layers of this groundbreaking disk are separated by just a single micrometer (0.00004 inches), enabling the researchers to combine many layers into a form no thicker than a DVD or Blu-Ray disk. The data is written and read across these many layers using precise lasers — a similar but significantly more advanced method than how a PlayStation reads a Blu-Ray disk.

“The ODS has a capacity of up to 1.6 [petabits] for a DVD-sized disk area through the recording of 100 layers on both sides of our ultrathin single disk,” the researchers explain.

This has massive implications for large data centers, sometimes occupying as much space as a sports stadium.

“It will thus become possible to build an exabit-level data center inside a room instead of a stadium-sized space by stacking 1,000 petabit-level nanoscale disks together… resulting in a large number of cost-effective exabit data centers,” the researchers say.

An exabit is 1,000 petabits or, put another way, one quintillion (1018) bits.

The research has been published in Nature, and its authors are Miao Zhao, Jing Wen, Qiao Hu, Xunbin Wei, Yu-Wu Zhong, Hao Ruan, and Min Gu.

Image credits: Header photo licensed via Depositphotos.