Holographic recording system having a relay system

Abstract

According to one aspect and example, a holographic recording system includes a light source, an object for modulating an object beam from the light source, and a relay system adapted to magnify (positive or negative) the modulated beam (e.g., an image of the object) to an output image. The object may include an SLM operable to modulate the object beam with an information layer comprising a plurality of data pages. The output image is directed to the holographic storage medium, where a reference beam is also directed, to record the resulting interference pattern. Additionally, the relay system converges the output image to an output Fourier plane, which may be disposed within the holographic storage medium. A filter may be placed at an intermediate Fourier plane located prior to the output Fourier plane, and a phase mask may be placed at the position of the output image.

1 . A holographic recording system, comprising:
 a light source;   an object for modulating an object beam produced by the light source;   a filter comprising an aperture for polytopic multiplexing;   a relay system for relaying an image of the object to an output image, wherein output of the relay system produces both the output image and an output Fourier plane, wherein an intermediate Fourier plane is formed in a path of the object beam prior to the output Fourier plane of the relay system and the filter is disposed at the intermediate Fourier plane location, and wherein the relay system is operable with the light source for directing the object beam to interfere with a reference beam at a holographic storage medium for recording holograms by polytopic multiplexing.   
     
     
         2 . The system of  claim 1 , further including a holographic storage medium, wherein the output image is directed to the holographic storage medium. 
     
     
         3 . The system of  claim 2 , wherein the output image is directed to intersect a reference beam and record a hologram associated with the object. 
     
     
         4 . The system of  claim 1 , wherein the object includes an SLM or data mask. 
     
     
         5 . The system of  claim 1 , wherein an intermediate Fourier plane is formed in a path of the object beam prior to the output Fourier plane of the relay system. 
     
     
         6 . The system of  claim 5 , further including a filter disposed at the intermediate Fourier plane location. 
     
     
         7 . The system of  claim 1 , wherein the filter includes an aperture and at least one dimension of the aperture is between 0.5 to 4.0 times the Nyquist aperture size for polytopic multiplexing. 
     
     
         8 . The system of  claim 1 , further including a phase mask disposed at the location of the object. 
     
     
         9 . The system of  claim 1 , further including a phase mask disposed at the location of the output image. 
     
     
         10 . The system of  claim 1 , wherein the output image includes a real or virtual image and is formed before the output Fourier plane. 
     
     
         11 . The system of  claim 1 , wherein the output image is a real image formed after the output Fourier plane. 
     
     
         12 . The system of  claim 1 , wherein an output beam divergence of the relay system is greater than a beam divergence of the illumination to the object. 
     
     
         13 . The system of  claim 1 , wherein the output numerical aperture of the relay system is greater than 0.2. 
     
     
         14 . The system of  claim 1 , wherein the relay system further magnifies the image of the object to the output image, and the magnification of the output image is between 0.1 and 10.0 times the size of the object. 
     
     
         15 . The system of  claim 1 , further including directing the object beam and a reference beam to interfere at a holographic storage medium for recording holograms by one or more of polytopically multiplexing, angle multiplexing holograms, wavelength multiplexing, shift multiplexing, correlation multiplexing, confocal multiplexing, or peristrophically multiplexing. 
     
     
         16 . A holographic recording system, comprising:
 a light source;   an object for modulating an object beam produced by the light source; and   a relay system adapted to produce an output image of the object, wherein output of the relay system produces both the output image and an output Fourier plane,   wherein an intermediate Fourier plane is formed in a path of the object beam prior to the output Fourier plane of the relay system and a filter is disposed at the intermediate Fourier plane location, the filter including an aperture for polytopic multiplexing, and wherein the relay system is operable with the light source for directing the object beam to interfere with a reference beam at a holographic storage medium for recording holograms by polytopical multiplexing.   
     
     
         17 . The system of  claim 16 , further including a holographic storage medium, wherein the output image is directed to the holographic storage medium. 
     
     
         18 . The system of  claim 17 , wherein the output image is directed to intersect a reference beam and record a hologram associated with the object. 
     
     
         19 . The system of  claim 16 , further including a phase mask disposed at the location of the output image. 
     
     
         20 . The system of  claim 16 , wherein an intermediate Fourier plane is formed in the object path prior to the output Fourier plane of the relay system. 
     
     
         21 . The system of  claim 20 , further including a filter disposed at the intermediate Fourier plane location. 
     
     
         22 . The system of  claim 16 , wherein the filter includes an aperture and at least one dimension of the aperture is between 0.5 to 4.0 times the Nyquist aperture size for polytopic multiplexing. 
     
     
         23 . The system of  claim 16 , wherein the relay system is further adapted to magnify the object the output image relative to the object. 
     
     
         24 . The system of  claim 23 , wherein the magnification is between 0.1 and 10.0. 
     
     
         25 . (canceled) 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . A method for recording holographic storage media, comprising:
 illuminating an object to produce a modulated object beam;   relaying the modulated object beam with a relay system to provide an output modulated object beam comprising an output Fourier transform pattern of the modulated object beam;   directing the output modulated object beam to a holographic storage medium;   propagating a reference beam to the holographic storage medium to record a resulting interference pattern between the output modulated object beam and the reference beam in the holographic storage medium, wherein the reference beam comprises a plane wave;   forming an intermediate Fourier plane prior to the output Fourier transform pattern of modulated object beam;   disposing an aperture at the intermediate Fourier plane location;   recording holograms via polytopic multiplexing by translating the holographic storage medium with respect to the reference beam and output modulated object beam between holograms, wherein a beam waist of the output modulated object beam is positioned outside of the holographic storage medium when recording each of the holograms, wherein at least two holograms; and   further including forming an intermediate Fourier plane prior to the output Fourier plane.   
     
     
         30 . The method of  claim 29 , further including disposing an aperture at the intermediate Fourier plane location. 
     
     
         31 . (canceled) 
     
     
         32 . (canceled) 
     
     
         33 . (canceled) 
     
     
         34 . (canceled) 
     
     
         35 . (canceled) 
     
     
         36 . (canceled) 
     
     
         37 . A method for recording holographic storage media, comprising:
 illuminating an object to produce a modulated object beam;   relaying the modulated object beam with a relay system to provide an output modulated object beam comprising an output Fourier transform pattern of the modulated object beam;   directing the output modulated object beam to a holographic storage medium;   propagating a reference beam to the holographic storage medium to record a resulting interference pattern between the output modulated object beam and the reference beam in the holographic storage medium, wherein the reference beam comprises a plane wave;   forming an intermediate Fourier plane prior to the output Fourier transform pattern of modulated object beam;   disposing an aperture at the intermediate Fourier plane location;   recording holograms via polytopic multiplexing by translating the holographic storage medium with respect to the reference beam and output modulated object beam between holograms, wherein a beam waist of the output modulated object beam is positioned outside of the holographic storage medium when recording each of the holograms, wherein at least two holograms; and   further including recording holograms by one or more of polytopically multiplexing, angle multiplexing holograms, wavelength multiplexing, shift multiplexing, correlation multiplexing, confocal multiplexing, or peristrophically multiplexing.   
     
     
         38 . The system of  claim 1 , wherein an object beam intersects a reference beam to record a hologram with a holographic storage medium, and the hologram is adapted for readout from the holographic storage medium without imaging optics. 
     
     
         39 . The system of  claim 16 , wherein an object beam intersects a reference beam to record a hologram with a holographic storage medium, and the hologram is adapted for readout from the holographic storage medium without imaging optics. 
     
     
         40 . The method of  claim 29 , wherein a beam waist associated with the output modulated object beam is positioned outside of the holographic storage medium when recording the holograms. 
     
     
         41 . The method of  claim 40 , further comprising disposing an aperture at the beam waist of each hologram during readout to filter out neighboring holograms.