CDs — yes CDs — are back (1)

In the ever-evolving landscape of digital storage, a surprising contender is poised to make a groundbreaking return: the Compact Disc (CD).

Once a staple of music and data storage, the CD’s popularity waned with the advent of more advanced technologies.

A recent innovation has rekindled interest in this ancient storage, promising to revolutionize data storage with unprecedented capacity.

A brief history of the CD

The compact disc, commonly known as the CD, was co-developed by Philips and Sony and introduced to the world in 1982.

Initially designed to store and play music, the CD quickly gained popularity due to its superior audio quality and durability compared to vinyl records and cassette tapes.

By the mid-1990s, CDs had become the dominant format for music and data storage, with billions of discs sold annually.

However, as technology progressed, CDs faced stiff competition from digital storage solutions such as USB flash drives, external hard drives, and cloud storage. The convenience and higher storage capacities of these alternatives led to the gradual decline of the CD.

By the early 2010s, the once-ubiquitous format had largely declined, relegated to the annals of tech history.

A new era for CD

The resurgence of interest in CDs can be attributed to a recent breakthrough that has dramatically increased their storage capacity.

Traditional CDs could store up to 700 MB of data, which was revolutionary in the 1980s but is minuscule by today’s standards.

Still, researchers at Shanghai University have developed a new type of CD that can hold an astonishing 1.6 petabits (Pb) of data. To put this into perspective, 1.6 petabits is equivalent to 200 terabytes (TB) or about 204,800 gigabytes (GB).

This remarkable increase in storage capacity is achieved through a novel approach to data encoding and disc manufacturing.

The new CDs utilize advanced nanotechnology to create ultra-dense data tracks, allowing for a dramatically higher amount of information to be stored on the same physical surface area.

Specifically, the technology involves stacking multiple layers of data within a single disc. Traditional CDs typically have a single data layer, while DVDs and Blu-ray discs may have up to four or five layers. The new high-capacity CDs can compress data into hundreds or even thousands of layers, exponentially increasing the storage capacity.

Reading and writing data on these multi-layered discs require highly sophisticated laser technology. Conventional CDs use infrared lasers with a wavelength of 780 nanometers, while DVDs use red lasers at 650 nanometers, and Blu-ray discs utilize blue-violet lasers at 405 nanometers.

(To be continued)