World's smallest QR code measures just under 2 square micrometers
The Institute of Materials Science and Technology at TU Wien now has its own entry in the Guinness Book of Records for the smallest QR code.
(Image: TU Wien)
TU Wien has been working with the Munich-based company Cerabyte for some time to develop a new long-term archiving technology: writing information onto a coated glass disc. In the lab, researchers use QR codes because they are relatively easy to read back – and one of the researchers had the idea to generate the world's smallest QR code.
According to the information, the current record was a code with an edge length of more than 2 micrometers. The Viennese researchers used focused ion beams to mill a QR code with an edge length of around 1.4 micrometers into a glass disc coated with chromium nitride. Since the individual dots of this code are only just under 50 nanometers wide, they cannot be resolved with visible light, let alone be recognized with the naked eye. However, the code could be recognized and read back under an electron microscope. If a complete DIN A4 page were written with such small QR codes, it would have a storage capacity of more than 2 terabytes.
(Image:Â TU Wien)
Technology for long-term archiving
The institute is developing the coating for the glass discs, with which Cerabyte is testing a new method of long-term archiving in its laboratory. Cerabyte currently uses much larger structures; currently, around 3 GByte of data fit onto a disc with an edge length of just under 10 centimeters. The capacity is to increase by several orders of magnitude later.
(Image:Â Lutz Labs / heise medien)
The ceramic layer on the glass discs, which are only 0.1 millimeters thick, is very robust; it is intended to last for many hundreds of years and be immune to all environmental influences. Cerabyte plans to pack more than 100 of these discs into a cassette the size of a Linear Tape Open (LTO) tape. These can be retrieved from their storage location by standard tape robots and brought to a reader.
Cerabyte currently uses a femtosecond laser to write to the discs, and a high-resolution camera is used for reading. More on this in the article Long-term data archiving with glass discs and femtosecond laser.
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