What is Bubble Memory?

Bubble memory is a type of computer memory invented during the 1970s by Andrew Bobeck. It is non-volatile, which means the data is stored even when the computer is shut down. Domains or “bubbles” produced on a magnetic film can store bits of data. Generally, one data bit is assigned to one bubble.

Aside from the magnetic film, units of bubble memory also consist of two permanent magnets that sandwich magnetic coils and electrodes in between. A magnetic shield encloses all the elements, but exposes several magnetic connectors on one side. If a user connects the unit to a power source, the magnets inside can create tiny bubbles on the film and store bits of memory. The bubbles are arranged in a pattern that follows the binary system. One bubble represents the binary digit one, and an absence of a bubble stands for zero.

Several companies produced and marketed the technology of bubble memory in an attempt to take the place of hard disks. Intel, Fujitsu, Rockwell, and Texas all made their own models of these memory units. The units were, at first, advantageous because they are detachable and highly resistant to different elements such as temperatures, humidity, and radiation. They were soon found to use so much power just to activate the bubbles and required a more complicated operating system compared to the hard disk. The manufacturing costs were also more expensive than the rivaled hard disk.

The bubble memory units were also too bulky; they were a bit smaller than the size of a regular matchbox, but thicker and heavier. They also had slower operating speeds and did not have random-access ability. By the early 1980s, the technology of hard disks became more advanced and the selling price became cheaper so that the production of bubble memory was discontinued.

While the bubble system did not become popular in modern-day computers and gadgets, it grew in the area of “rugged” factory machineries, mainly because of its physical resistance and non-volatile quality. It was also used temporarily in video games, in which memory cartridges can be detached and exchanged to make games. Its sturdiness also made it a preference for military use even after its discontinued production. The development, however, of other non-volatile memory units such as compact discs and universal serial bus (USB) keys, made it more difficult for the bubble memory to resurface. The smaller sizes of the more modern devices, not to mention the higher memory capacity, also added to the bubble system’s obsoleteness.