| 摘要 |
A two-dimensional matrix code (101), method of producing the code and a method and device for reading the code are presented. The code is a round, compact and distinct code that stores an error-corrected 64-bit number, embedded targets, and quality control information within a space small enough for imaging using a compact, hand-held code finder (107). The code incorporates white space (305) both between the data areas (303) and targets (301) for easy identification of the code and to aid in image processing, and within the data area to correct for errors that sometimes occur when printing using low-quality techniques. Additionally, the code includes features to correct for other printing errors, such as variations in printing press speed and intentional aspect ratio stretching to fill copy space. The code is thus robust enough to be incorporated within newsprint and is also easily imaged using specially constructed code finders. A code finder device and a method of using the finder for acquiring a code of the present invention is also presented. The finder is portable and easy to use, requiring no rotational orientation for correct acquisition. Several embodiments are described, in which the finder contains illumination and communications electronics and means to notify the user of correct operation of the finder. |
