Two-dimensional code mark detecting method and apparatus therefor

摘要

A method of and an apparatus for detecting information from a code marking formed on a carrier by illuminating the code marking with illuminating light and detecting an emission from an illuminated position on which the illuminating light is projected. The code marking is a two-dimensional code marking bearing the information in first and second directions perpendicular to each other, and an illuminated area at the illuminated position is of a fine ribbon-like shape having a length greater than a maximum possible width of the code marking in the first direction and smaller than a minimum possible information width in the second direction. Illumination of the code marking is carried out by moving in a direction parallel to the second direction while traversing in the first direction.