Naosato Taniguchi

Off-axial HMD optical system consisting of aspherical surfaces without rotational symmetry

An off-axial optical system is desirable for a see-through head mounted display (HMD) with a wide field of view (FOV). Using our new off-axial paraxial theory and the fabricating methods, we have achieved to correct the off-axial aberrations of the optical systems which consists of an aspherical surfaces without rotational symmetry. In this paper, we describe 3 types of off-axial HMD optical systems. (1) The first one is a hologram for a monochromatic HMD. The hologram has been recorded the wavefront generated by computer generated hologram. The image spot size is about 15 micrometers over 9 degree FOV. (2) The second one is an aspherical mirror system for a color HMD. The designed image spot size is less than 30 micrometers over 43.5 degree FOV. The shape error of the fabricated mirror is measured by a contact probing from 1.0 micrometers to 1.9 micrometers . The maximum resolution is 36 lp/mm. (3) The last one is a prism with aspherical surfaces, 34 degree FOV and less than 15 mm thickness. The monocular HMD with only 80 g weight has been developed. The line of sight detecting device has been applied as an interactive man-machine interface.

Reflection holograms recorded on poly-(N-vinylcarbazole) holographic material.

We present preliminary results concerning reflection type hologramsi n poly(N-vinylcarbazole)(P VCz) that appear to confirm that PVCz is comparable to dichromated gelatin for thick reflection holograms.