Recently [mit41301] wondered about increasing the data capacity of QR codes, and was able to successfully triple the number of bits using color. He chose the new rectangular micro QR code (rMQR ...

The hardware is built around nine 8×8 LED matrix panels resulting in a 24 x 24 pixel display, perfect for displaying a 21 pixel square QR code. The LED drivers are a standard multiplexed affair ...

Asakusa Line stations with platform safety gates now have three cameras above to read the QR codes. When a train arrives, the cameras scan the 15-centimeter-square QR codes affixed on train doors ...