QR codes
Denso Wave's masterpiece that survived its own patents.
Where it came from
Masahiro Hara at Denso Wave invented the QR code in 1994 to track car parts on Toyota assembly lines — the 2D layout let workers scan codes at speed from any angle. Denso declined to exercise its patents, which is why QR conquered the planet instead of dying in a factory.
The pandemic turned it into everyday infrastructure: menus, tickets, payments.
How it works
A QR code is a grid of modules (21×21 for version 1 up to 177×177 for version 40) containing data encoded in bits, plus fixed function patterns: finder squares in corners, timing strips, format info.
The magic ingredient is Reed-Solomon error correction — up to 30% of the code can be damaged or covered (that's why logos-in-QR work) and it still scans. Mask patterns are applied to avoid pathological arrangements that confuse readers.
UWC generates QR codes with the qrcode library and scans them from images with jsQR — both run entirely in your browser, so sensitive payloads (WiFi passwords, TOTP seeds) never leave the device.