Hughes Aircraft Company

Timothy J Edwards

John E Wreede

Gaylord E Moss

James A Arns

The systems of the invention form improved reflection and transmission holograms utilizing two beams and eliminating all of the higher energy spurious holographic recordings that are caused by reflections of rays from the outer surfaces of the cover plates. The systems provide movement of the cover plate or movement of the substrate and recording medium during the recording period to prevent formation of the spurious recordings. In some arrangements of the invention, global phase shifters are utilized to maintain the phase of the primary rays forming the desired hologram at a high level.

Double beam systems for forming improved holograms

A hologram forming system for forming, from a single beam source and a reflective mirror, a reflective hologram in which spurious reflection and transmission hologram recordings are eliminated. Reflected rays are changed in phase relative to the primary beams during the recording period so that spurious holograms do not form. The remaining effect of the reflected rays is to slightly change the overall refractive index of a phase recording material (such as dichromated gelatin) with a resultant slight loss of available index of modulation or to slightly, uniformly, darken an amplitude hologram film, (such as silver halide) with a slight loss of available contrast. The invention includes hologram forming systems that move the cover plate relative to a fixed recording medium with and without a phase shifter in the primary beam and a hologram forming system that moves the substrate and mirror relative to the fixed cover plate.

Systems for forming improved reflection holograms with a single beam

The hologram forming systems of the invention form diffusion type holograms in which undesired spurious transmission hologram recordings are eliminated. The reflecting surfaces are moved during the recording process so that the reflected rays change in phase relative to the primary recording beams and spurious holograms cannot be recorded with sufficient intensity to form undesired reflections in the developed hologram. Thus, pictorial type holograms such as jewelry holograms or art holograms do not present undesired ghost images or flare patterns to the viewer. The concepts of the invention also include formation of diffusion type holograms for high gain directional viewing screens.

Growing community of inventors

Hermosa Beach, CA, United States of America

Timothy J Edwards