German physicists create the world's tiniest QR code

A team of physicists from the University of Münster has created the world's smallest QR code, earning them a place in the Guinness Book of Records.
The QR code measures 5.38 square micrometres, which, according to the university, is approximately 20 times smaller than the previous world record held by a research group from Singapore and about seven times smaller than a human red blood cell.
The QR code cannot be seen with the naked eye, but a university spokesman said it can be magnified multiple times on a computer screen using a microscope.
The code, which links to the university's quantum physics website, was recognized as a record by Guinness World Records following independent measurements by a technology company. The university wants to use this record to promote the study of physics.