Ultra-High Efficiency Color Mixing and Color Separation

Abstract

Methods and apparatus for combining or separating spectral components by means of a polychromat. A polychromat is employed to combine a plurality of beams, each derived from a separate source, into a single output beam, thereby providing for definition of one or more of the intensity, color, color uniformity, divergence angle, degree of collimation, polarization, focus, or beam waist of the output beam. The combination of sources and polychromat may serve as an enhanced-privacy display and to multiplex signals of multiple spectral components. In other embodiments of the invention, a polychromat serves to disperse spectral components for spectroscopic or de-multiplexing applications.

What is claimed is: 
     
         1 . A color-combining apparatus comprising:
 a. a plurality of sources of illumination, each source of illumination emitting a beam characterized by a distinct spectral range, the plurality of beams comprising a set of beams; and   b. a polychromat adapted to define light output properties in at least one volume upon illumination of the polychromat by the plurality of sources of illumination.   
     
     
         2 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to define light output properties in a plurality of volumes upon illumination of the polychromat by the plurality of sources of illumination. 
     
     
         3 . The color-combining apparatus of  claim 2 , wherein the light output properties defined in at least two of the plurality of volumes are mutually distinct light output properties. 
     
     
         4 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to combine the set of beams into an output beam. 
     
     
         5 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to define a propagation direction of the output beam. 
     
     
         6 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to define at least one property of light in a specified volume of space, the one property chosen from the group of properties including:
 (i) intensity;   (ii) color;   (iii) color uniformity; and   (iv) polarization.   
     
     
         7 . The color-combining apparatus of  claim 4 , wherein the polychromat is adapted to define at least one property of the output beam, the one property chosen from the group of properties including:
 (i) intensity;   (ii) color;   (iii) color uniformity;   (iv) divergence angle;   (v) degree of collimation;   (vi) polarization;   (vii) focus; and   (viii) beam waist.   
     
     
         8 . The color-combining apparatus of  claim 1 , wherein the distinct spectral ranges of the respective sources of illumination are substantially spectrally non-overlapping. 
     
     
         9 . The color-combining apparatus of  claim 1 , further comprising a computer-generated holographic plate disposed between each source of illumination and the polychromat. 
     
     
         10 . The color-combining apparatus of  claim 1 , wherein the plurality of sources are disposed on a non-planar substrate. 
     
     
         11 . The color-combining apparatus of  claim 1 , further comprising at least one controller for independently controlling each light source. 
     
     
         12 . The color-combining apparatus of  claim 1 , wherein a subset of the plurality of sources, up to the entirety thereof, share a common electrode. 
     
     
         13 . The color-combining apparatus of  claim 1 , wherein the polychromat is fabricated on a transparent material. 
     
     
         14 . The color-combining apparatus of  claim 1 , wherein the polychromat is fabricated on an absorbing material. 
     
     
         15 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to operate in a transmission mode. 
     
     
         16 . The color-combining apparatus of  claim 1 , wherein the polychromat is adapted to operate in a reflection mode. 
     
     
         17 . The color-combining apparatus of  claim 1 , wherein the polychromat is binary, multi-level or has a gradient index of refraction distribution. 
     
     
         18 . The color-combining apparatus of  claim 1 , wherein the polychromat includes a parquet of polychromats. 
     
     
         19 . A method for at least one of multiplexing and demultiplexing optical signals, the method comprising:
 a. illuminating a polychromat with electromagnetic radiation from plurality of sources, each source characterized by a distinct spectral range and emitting a distinct spectral component;   b. combining the electromagnetic radiation from the plurality of sources for coupling into an optical conduit having an output; and   c. coupling the output of the optical conduit to a second polychromat for separating the electromagnetic radiation into the distinct spectral components.   
     
     
         20 . An improvement to a spectrometer having a dispersive element for dispersing spectral components of a light input, the improvement comprising:
 substitution of the dispersive element with a polychromat.   
     
     
         21 . The improved spectrometer of  claim 20 , wherein the polychromat is optimized for achieving a specified diffraction efficiency. 
     
     
         22 . The improved spectrometer of  claim 20 , wherein the polychromat is optimized to direct spectral bands onto specified detector pixels. 
     
     
         23 . The improved spectrometer of  claim 20 , wherein the polychromat is optimized to suppress specified diffraction orders. 
     
     
         24 . The improved spectrometer of  claim 20 , wherein the polychromat is optimized to increase input light acceptance of the spectrometer. 
     
     
         25 . The improved spectrometer of  claim 20 , wherein the polychromat serves as a powered diffractive optic, focusing diffracted light onto the detector array.