Why do QR codes work from any angle?
Show answer & explanation
Answer: Corner patterns provide orientation
Codes repeat in all directions — Wrong. QR codes don't repeat. They have three corner squares (finder patterns) that indicate orientation, allowing scanners to read from any angle.
Special algorithms detect rotation — Wrong. Algorithms do process rotation, but QR codes specifically include three corner squares providing orientation reference for decoding.
Corner patterns provide orientation ✓ — Correct! QR codes have three distinctive corner squares (finder patterns)—one in each corner except bottom-right. Scanners detect these patterns first to determine orientation and rotation. This allows reading from any angle—0°, 90°, 180°, 270°, or even skewed. The fourth corner uses a smaller alignment pattern. Clever geometric design!
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