Method and apparatus for production of holographic optical elements

Claim 1

A holographic optical element assembly comprising: a fabrication reflection holographic optical element, said fabrication reflection holographic optical element comprising a developed first reflection grating means for forming a first image when illuminated from a first preselected focal point, said first reflection grating means being positioned between a substrate and a cover plate, said first reflection grating means being configured for producing a system combiner holographic optical element; and an undeveloped system combiner holographic optical element, said undeveloped system combiner holographic optical element having a substrate with a photosensitive layer thereon, said undeveloped system combiner holographic optical element lying adjacent and in front of said fabrication reflection holographic optical element, so that when exposed to a source of coherent radiation to which said photosensitive layer is sensitive from the side of said undeveloped system combiner holographic optical element away from said fabrication reflection holographic optical element, a latent image of second grating means is exposed in said undeveloped system combiner holographic optical element photosensitive layer, that latent image of a second grating means being such that when it is developed it is a combiner grating means for producing a second image different than the first image when illuminated from a second preselected focal point and is a desired image combiner grating.

Claim 7

An apparatus for the production of combiner holographic optical elements comprising: a point source of coherent radiation; a fabrication reflection holographic optical element having first reflection grating means thereon for producing a first image when illuminated by said point source from a first predetermined focal distance, said fabrication reflection holographic optical element being positioned with respect to said point radiation source; and a photosenstive layer on a substrate for production of a system combiner holographic optical element, said photosensitive layer being positioned against said fabrication reflection holographic optical element on the side thereof toward said point source with index matching fluid therebetween to substantially match the index of refraction therebetween and being positioned with respect to said radiation source so that when exposed to radiation directly from said source and from radiation from said source reflected from said fabrication reflection holographic optical element having the first reflection grating means thereon, a latent image of a combiner grating means is produced in said photosensitive layer, the latent image of said combiner grating means being such that when developed and placed in an optical display device and illuminated by a point source from a second focal distance the combiner grating means in the developed system combiner holographic optical element produces the correct optical effect in said optical display.

Claim 8

An apparatus for the production of combiner holographic optical elements comprising: a point source of coherent radiation; a fabrication reflection holographic optical element having first reflection grating means thereon for producing a first image when illuminated by said point source from a first predetermined focal distance, said fabrication reflection holographic optical element being positioned with respect to said point radiation source; and a photosenstive layer on a substrate for production of a system combiner holographic optical element, said photosensitive layer being positioned against said fabrication reflection holographic optical element on the side thereof toward said point source with index matching fluid therebetween to substantially match the index of refraction therebetween and being positioned with respect to said radiation source so that when exposed to radiation directly from said source and from radiation from said source reflected from said fabrication reflection holographic optical element having the first reflection grating means thereon, a latent image of a combiner grating means is produced in said photosensitive layer, the latent image of said combiner grating means being such that when developed and placed in an optical display device and illuminated by a point source from a second focal distance the combiner grating means in the developed system combiner holographic optical element produces the correct optical effect in said optical display.

Claim 12

The method of making a system combiner holographic optical element comprising the steps of: exposing the latent image of a first grating in a photosensitive layer by coherent radiation from object and reference beam point sources with the object beam point source being positioned at a first predetermined distance from the first photosensitive layer; developing the first photosensitive layer to provide a first reflection grating which is the grating in a fabrication reflection holographic optical element which serves as an intermediate element to the production of a desired combiner grating; providing an undeveloped system combiner holographic optical element substrate with an unexposed photosensitive layer thereon; positioning the fabrication reflection holographic optical element against the undeveloped system combiner holographical optical element substrate on the side thereof away from a second point radiation source; exposing the photosensitive layer in the undeveloped system combiner holographic optical element substrate by coherent radiation both directly from the second point radiation source at a preselected distance from the undeveloped system combiner holographic optical element, and reflecting from the grating in the fabrication reflection holographic optical element from the second point radiation source, to form a grating latent image in the photosensitive layer of the undeveloped system combiner holographic optical element; developing the latent image in the photosensitive layer of the undeveloped system combiner holographic optical element to produce a developed combiner grating which produces the desired optical result; and covering the developed combiner grating of the system holographic optical to form a complete system holographic optical element.

Claim 13

The method of making a system combiner holographic optical element comprising the steps of: exposing the latent image of a first grating in a photosensitive layer by coherent radiation from object and reference beam point sources with the object beam point source being positioned at a first predetermined distance from the first photosensitive layer; developing the first photosensitive layer to provide a first reflection grating which is the grating in a fabrication reflection holographic optical element which serves as an intermediate element to the production of a desired combiner grating; providing an undeveloped system combiner holographic optical element substrate with an unexposed photosensitive layer thereon; positioning the fabrication reflection holographic optical element against the undeveloped system combiner holographical optical element substrate on the side thereof away from a second point radiation source; exposing the photosensitive layer in the undeveloped system combiner holographic optical element substrate by coherent radiation both directly from the second point radiation source at a preselected distance from the undeveloped system combiner holographic optical element, and reflecting from the grating in the fabrication reflection holographic optical element from the second point radiation source, to form a grating latent image in the photosensitive layer of the undeveloped system combiner holographic optical element; developing the latent image in the photosensitive layer of the undeveloped system combiner holographic optical element to produce a developed combiner grating which produces the desired optical result; and covering the developed combiner grating of the system holographic optical to form a complete system holographic optical element.