This paper introduces a new technique for producing augmented reality systems that simultaneously identify real world objects and estimate their coordinate systems. This method utilizes a 2D matrix marker, a square shaped barcode, which can identify a large number of objects. It also acts as a landmark to register information on real world images. As a result, it costs virtually nothing to produce and attach codes on various kinds of real world objects, because the matrix code are printable. We have: developed an augmented reality system based on this method, and demonstrated several potential applications.