Timing Pattern

Timing patterns consist of two lines: a horizontal line connecting the top-left and top-right finder patterns, and a vertical line connecting the top-left and bottom-left. Modules alternate one by one between black and white, serving as a "ruler" for scanners to accurately count module coordinates.

Even when module spacing becomes uneven due to print distortion or camera angle, the alternating timing pattern enables calculation of each module's exact position. Working together with finder and alignment patterns, they enable high-speed, high-accuracy QR code reading.