Abstract: In order to improve the virtual-real registration efficiency of augmented reality system for medical
auxiliary operation, a regular hexahedron three-dimensional marker based on hamming code put forward as the
characteristic pattern was designed. The system detected and identified the marker, and POSIT(Pose from
Orthography and Scaling with Iterations)algorithm was used to obtain the camera position for the characteristics of
the three-dimensional marker and the size of the marker was optimized by experiment. The virtual skull model
after CT(Computed Tomography) reconstruction was real-time displayed in the real scene using the transfer
matrix obtained from POSIT. Experiments proved the marker’s effectiveness.

Key words: augmented reality, virtual-real registration, marker design