A 2D Ternary Barcode Detection System with a Dual Threshold

A 2D ternary barcode detection system employing a dual threshold method has been developed to increase both detection speed and range. This system, adaptable to any ternary barcode pattern through the subtraction of each attenuated enveloped line of two sampled detected barcode signals from the original sampled signals, respectively, enables long range detection at higher scanning speeds while still containing a large amount of information. The prototype system, combined with a time-sharing laser light emission method that allowed the system to double effective scanning speeds, and using a two-line ten-character ternary barcode consisting of nine elements per character with a minimum bar width of 0.4 mm, was confirmed to successfully detect over a range of more than 5 cm at a maximum scanning speed of 835 scan/sec, which is 16 times higher than conventional CCD cameras. This system is expected to enable the real-time identification of goods on production lines and in automated warehouses.