| 摘要 |
PROBLEM TO BE SOLVED: To provide a secure bar code helping defense against forgery of a document including a bar code, and to provide a method for creating the same.SOLUTION: The primary pattern of a two-dimensional bar code 411 to be printed on a substrate is constituted of a set of dark cells and a set of bright cells. A secondary pattern 502 of the same size as that of the two-dimensional bar code 411 is created. The pattern is constituted of a micro shape having a size equal to or smaller than that of each cell of the two-dimensional bar code. A secure bar code 512 is created by masking the secondary pattern with the primary pattern of the two-dimensional bar code 411. In a resulting two-dimensional bar code, a dark cell is represented by a dark cell, and coded data can be represented by a set with a bright cell by the secondary pattern having the micro shape.SELECTED DRAWING: Figure 5 |
