Multi-input image light guide system

An image light guide system for conveying a virtual image, comprising:

• a first and a second waveguide, each of said first and second waveguides operable to propagate image-bearing light beams, said first and second waveguides each having first and second parallel surfaces, wherein said first parallel surface of said first waveguide is an inner surface facing said second waveguide, and wherein said first parallel surface of said second waveguide is an inner surface facing said first waveguide;
• a first in-coupling diffractive optic formed along said inner surface of said first waveguide and disposed to direct image-bearing light beams into said first waveguide, wherein said first in-coupling diffractive optic comprises a first plurality of diffractive structures having a first periodicity and is operable to diffract at least a first part of a first portion of said image-bearing light beams into said first waveguide in an angularly encoded form,
• a second in-coupling diffractive optic formed along said inner surface of said first waveguide and disposed to direct image-bearing light beams into said first waveguide, wherein said second in-coupling diffractive optic comprises a second plurality of diffractive structures having a second periodicity different from said first periodicity and is operable to diffract a second portion of said image-bearing light beams into said first waveguide in an angularly encoded form;
• a first out-coupling diffractive optic formed along said inner surface of said first waveguide, wherein said first out-coupling diffractive optic is operable to expand said first portion and said second portion of said image-bearing light beams and direct said expanded first portion and said expanded second portion of said image-bearing light beams from said first waveguide in an angularly decoded form;
• a first intermediate diffractive optic formed along said inner surface of said first waveguide and operable to direct said second portion of said image-bearing light beams to said first out-coupling optic;
• and
• a third in-coupling diffractive optic formed along said first inner surface of said second waveguide and disposed to direct image-bearing light beams into said second waveguide, wherein said third in-coupling diffractive optic comprises a third plurality of diffractive structures having a third periodicity and is operable to diffract at least a second part of said first portion of said image-bearing light beams into said second waveguide in an angularly encoded form;
• and
• a fourth in-coupling diffractive optic formed along said inner surface of said second waveguide and disposed to direct image-bearing light beams into said second waveguide, wherein said fourth in-coupling diffractive optic comprises a fourth plurality of diffractive structures having a fourth periodicity different from said third periodicity and is operable to diffract a third portion of said image-bearing light beams into said second waveguide in an angularly encoded form.