| 摘要 |
<p>Provided is a technique of measuring the position of an object to be printed and disposed at a distance and allowing the object to display automatic recognition data. A light-emitting device including a predetermined R(red) light-emitting element, a predetermined G(green) light-emitting element, a predetermined B light-emitting element, and a controller for controlling their operating states is attached to an object to be printed. The light-emitting elements are allowed to emit lights in a predetermined light-emitting pattern. The light-emitting pattern is stored in a predetermined storage means. The light-emitting pattern forms a time-varying optically recognized code representing desired data when the colors vary along the time axis. As a result, compared to conventional two-dimensionally optically recognized codes constituted by arranging colors, a small-area optically recognized code is realized. When the light-emitting device is imaged with, e.g., a CCD camera, the position of the light-emitting device, i.e., the position of the object can be determined. If the operation is continued, the object can be tracked.</p> |
