US 5,793,504 A · Hybrid angular/spatial holographic multiplexer

Abstract

A plurality of holograms are simultaneously angularly and spatially multiplexed within a storage medium by writing the holograms at different locations within the storage medium using reference and object beams directed thereto via cooperating reference beam and object beam scanners, respectively. The simultaneously angular and spatially multiplexed holograms are subsequently read-out by directing a reference beam through a desired location within the storage medium using the reference beam scanner. The reference beam is directed from the storage medium to a phase conjugator which conjugates the phase of the reference beam and directs the phase conjugated reference beam back to the same desired location within the storage medium so as to excite a corresponding conjugate object beam which is then directed onto a detector array.

Claims25

Dependent claims

A hybrid angular/spatial holographic multiplexer comprising:

a) a storage medium;
b) a reference beam scanner for scanning a reference beam spatially through said storage medium;
c) an object beam scanner for scanning an object beam spatially through said storage medium;
d) a spatial light modulator for modulating a laser beam to form the object beam;
e) a phase conjugator for conjugating the reference beam during read-out so as to excite a corresponding conjugate object beam;
f) a detector array for converting the conjugate object beam into an electrical signal representative thereof;
and
g) wherein said reference beam scanner and said object beam scanner cooperate to form a plurality of angular/spatial multiplexed holograms within said storage medium.

5 more elements

A method for angularly and spatially multiplexing a plurality of holograms within a storage medium, said method comprising the steps of:

a) performing a write operation comprising the steps of:
(i) directing a reference beam to a desired location within the storage medium via a reference beam scanner;
(ii) directing an object beam to the same desired location within the storage medium via an object beam scanner;
(iii) forming a hologram within the storage medium via interference of the reference beam and the object beam;
(iv) repeating steps (i) through (iii) for a plurality of different desired locations within the storage medium for forming a plurality of angularly/spatially multiplexed holograms;
b) performing a read-out operation comprising the steps of:
(i) directing a reference beam to a desired location within the storage medium via a reference beam scanner;
(ii) directing the reference beam from the storage medium to a phase conjugator;
(iii) conjugating the phase of the reference beam;
and
(iv) directing the excited corresponding conjugate object beam onto a detector array via the object beam scanner.

8 more elements

Dependencies are inferred from the claim text.

Hybrid angular/spatial holographic multiplexer

Life of this patent

Hybrid angular/spatial holographic multiplexer

Life of this patent

Abstract

Claims25