QR Code Corner Squares Explained

QR codes use three corner 'finder patterns' that help cameras identify and orient the code for fast decoding.

Denso Wave, a Japanese company, invented the Quick Response format in 1994 to track parts on automobile assembly lines.

The three finder patterns allow the camera to determine orientation and flatten distorted images; the fourth corner is left empty for more data storage.

QR codes use Reed-Solomon error correction, enabling them to be read even if up to 30% damaged or covered.

Scanning can fail if the 'quiet zone' is missing, or due to low contrast, glare, or poor lighting.