Multi-part optical system for light propagation in confined spaces and method of fabrication and use thereof

Abstract

The present invention is a Substrate guided hologram that allows a wider range of optical devices based on SGHs with improved parameters such as larger NTE displays with a wider field of view, thinner substrates and more compact form factors. The Substrate-Guided Hologram of the subject invention includes a holographic lens which is positioned at an angle to and spaced from a holographic grating, with a mirror located at a diagonal to each of the lens and the grating.

1 .- 5 . (canceled) 
     
     
         6 . An optical system comprising:
 (a) a light source comprising a light beam;   (b) a holographic lens fixed to a first substrate spaced in proximity of the light source at or within the focal distance of the holographic lens;   (c) a holographic grating fixed to a second substrate spaced apart from and at an angle to the first substrate;   (d) a mirror located at a diagonal to and between the holographic lens and the holographic grating;   wherein the light beam travels from the light source through the first substrate to the holographic lens then through the first substrate by total internal reflection to bounce off the mirror into the second substrate to the holographic grating by total internal reflection and then out-coupled for viewing by a user.   
     
     
         7 . The optical system of  claim 6  therein the first substrate has a different refractive index from the second substrate. 
     
     
         8 . The optical system of  claim 6  wherein the first substrate has a larger refractive index than the holographic lens. 
     
     
         9 . The optical system of  claim 6  wherein the second substrate has a smaller index of refraction than the holographic grating. 
     
     
         10 . The optical system of  claim 6  further comprising a helmet to which the optical system is mounted. 
     
     
         11 . The optical system of  claim 6  wherein the holographic lens is positioned perpendicularly to the holographic grating. 
     
     
         12 . The optical system of  claim 6  wherein the holographic lens is positioned at an angle comprising 0° to 360° relative to the holographic grating. 
     
     
         13 . The optical system of  claim 6  wherein the holographic lens is positioned at an angle comprising 45° to 135° relative to the holographic grating. 
     
     
         14 . The optical system of  claim 6  wherein the holographic lens is spaced apart from the holographic grating at a distance comprising 5-10 mm. 
     
     
         15 . The optical system of  claim 6  wherein each substrate is independently substantially or entirely transparent. 
     
     
         16 . The optical system of  claim 6  wherein each substrate independently comprises glass, or plastic. 
     
     
         17 . The optical system of  claim 6  wherein the plastic comprises polycarbonate, acrylic, or polyolefin. 
     
     
         18 . The optical system of  claim 6  wherein each substrate independently comprises a thickness in the range of 0.3 to 6 mm. 
     
     
         19 . The optical system of  claim 6  wherein each substrate independently comprises a plurality of bodies or a single body. 
     
     
         20 . The optical system of  claim 6  wherein each substrate independently comprises a plurality of layers or a single layer. 
     
     
         21 . The optical system of  claim 6  wherein each substrate independently comprises a plurality of bodies or a single body. 
     
     
         22 . The optical system of  claim 6  wherein each substrate comprises an index of refraction sufficient to internally reflect the light beam relative to the environment. 
     
     
         23 . The optical system of  claim 6  wherein one or both of the substrates independently comprises a color tint. 
     
     
         24 . The optical system of  claim 6  wherein one or both of the substrates independently comprises flexibility. 
     
     
         25 . The optical system of  claim 6  wherein the light source is a microdisplay.