Development of a stereo video see-through HMD for AR systems

Geometrical studies and experiments were done in order to specify requirements for the imaging and display systems of a stereo video see-through HMD for AR systems. It was found that it is necessary to set the left and right optical axes of the stereoscopic imaging system to be parallel to one another, and likewise for the display system. It was also found that, for AR applications handling real space at short distances, it is necessary to align the optical axes of the imaging system with the optical axes of the display system in order to avoid spatial perception error. We refer this as the 'parallax-free'. Based on these studies and experiments, a parallax-free stereo video see-through HMD with wide field-of-view was developed. It was also confirmed experimentally that a small displacement of the entrance pupils of the imaging system along the axes to the exit pupils of the display system does not cause serious spatial perception errors. By displacing the position of the entrance pupils of the imaging system by 30mm, we have downsized the HMD to a thickness of 36mm and lighten it to 340g. The HMD was then actually applied to an AR system and its usefulness was verified.