摘要 |
A dot pattern formed on a medium surface and not visually recognized, generally called a stealth dot pattern, is simply and inexpensively realized by slightly improving the existing printing technique. The dot pattern is used in a dot pattern read system in which infrared or ultraviolet light is applied to a medium surface on which the dot pattern is formed, the reflected light is read by optical read means to recognize the dot pattern, the dot pattern is converted into data corresponding to this, and a text, a sound, an image, or the like is outputted. On the medium surface, a dot constituting the dot pattern is formed by printing with an ink of an arbitrary color reactive in the infrared or ultraviolet wavelength region. |