Holographic optical elements for augmented reality devices and methods of manufacturing and using the same

Abstract

Holographic optical elements for augmented reality (AR) devices and methods of manufacturing and using the same are disclosed. A disclosed system includes a holographic optical element (HOE), and a first light source to direct a first beam of light toward the HOE from a first direction. The first beam of light is collimated. The disclosed system further includes a second light source to direct a second beam of light toward the HOE from a second direction. The disclosed system also includes a decollimation lens positioned between the first light source and the HOE. The decollimation lens is to decollimate the first beam of light.

What is claimed is: 
     
         1 . A system comprising:
 a holographic optical element (HOE);   a first light source to direct a first beam of light toward the HOE from a first direction, the first beam of light being collimated;   a second light source to direct a second beam of light toward the HOE from a second direction; and   a decollimation lens positioned between the first light source and the HOE, the decollimation lens to decollimate the first beam of light.   
     
     
         2 . The system as defined in  claim 1 , wherein a focal length of the decollimation lens defines a focal point for chief rays of sub-images to be reflected off the HOE from a projector. 
     
     
         3 . The system as defined in  claim 2 , wherein the decollimation lens is a diverging lens, the diverging lens positioned between the focal point for the chief rays and the HOE. 
     
     
         4 . The system as defined in  claim 3 , wherein the second beam of light is to converge towards a second focal point, the second focal point defining a location for the projector. 
     
     
         5 . The system as defined in  claim 2 , wherein the decollimation lens is a converging lens, the HOE positioned between the focal point for the chief rays and the converging lens. 
     
     
         6 . The system as defined in  claim 5 , wherein the second beam of light is to diverge outward from a second focal point, the second focal point defining a location for the projector. 
     
     
         7 . The system as defined in  claim 2 , further including a lens array positioned between the decollimation lens and the HOE, the lens array to focus separate portions of the first beam of light to separate focal points on a focal plane between the focal point for the chief rays and the HOE. 
     
     
         8 . A method comprising:
 positioning a decollimation lens adjacent to a holographic optical element (HOE);   transmitting a first beam of light through the decollimation lens towards a first side of the HOE; and   transmitting a second beam of light towards a second side of the HOE.   
     
     
         9 . The method as defined in  claim 8 , defining a focal point for chief rays of sub-images to be reflected off the HOE from a projector based on a focal length of the decollimation lens. 
     
     
         10 . The method as defined in  claim 9 , further including positioning the decollimation lens between the focal point for the chief rays and the HOE, the decollimation lens being a diverging lens. 
     
     
         11 . The method as defined in  claim 10 , wherein the second beam of light is to converge towards a second focal point, the method further including defining a location for the projector based on a location of the second focal point. 
     
     
         12 . The method as defined in  claim 9 , further including positioning the HOE between the focal point for the chief rays and the decollimation lens, the decollimation lens being a converging lens. 
     
     
         13 . The method as defined in  claim 12 , wherein the second beam of light is to diverge from a second focal point, the method further including defining a location for the projector based on a location of the second focal point. 
     
     
         14 . The method as defined in  claim 9 , further including positioning a lens array between the decollimation lens and the HOE to focus separate portions of the first beam of light to separate focal points on a focal plane between the focal point for the chief rays and the HOE. 
     
     
         15 . An apparatus comprising:
 means for reflecting;   means for directing a first beam of light toward the reflecting means from a first direction, the first beam of light being collimated;   means for directing a second beam of light toward the reflecting means from a second direction; and   means for decollimating light, the light decollimating means positioned between the first beam of light directing means and the reflecting means, the light decollimating means to decollimate the first beam of light.   
     
     
         16 . The apparatus as defined in  claim 15 , wherein a focal length of the light decollimating means defines a focal point for chief rays of sub-images to be reflected off the reflecting means from means for projecting. 
     
     
         17 . The apparatus as defined in  claim 16 , wherein the light decollimating means is a diverging lens, the diverging lens positioned between the focal point for the chief rays and the reflecting means. 
     
     
         18 . The apparatus as defined in  claim 17 , wherein the second beam of light is to converge towards a second focal point, the second focal point defining a location for the projecting means. 
     
     
         19 . The apparatus as defined in  claim 16 , wherein the light decollimating means is a converging lens, the reflecting means positioned between the focal point for the chief rays and the converging lens. 
     
     
         20 . The apparatus as defined in  claim 19 , wherein the second beam of light is to diverge outward from a second focal point, the second focal point defining a location for the projecting means.