Recognition of two-dimensional matrix code mounted on moving object, using bright-dark information of alternating pattern adjacent to finder pattern as clock signal for reading process

摘要

Two-dimensional matrix code of bright-dark modules in lines and columns, is enclosed by continuos beam along two colliding edges, forming finder pattern. Remaining edges are formed by alternating pattern of bright- and dark modules. Matrix code is moved through field of vision of line sensor, aligned so finder pattern beam lies parallel to line sensor, bright- and dark information of alternating pattern adjacent to finder pattern is used as clock signal for reading.