A projection display, comprising: an image generator for generating colour images comprising image-bearing chromatic light having a range of wavelengths for injection into a waveguide assembly over a field of view comprising a first range of field angles and a second, different range of field angles, the waveguide assembly comprising: a first waveguide having a first input diffraction region arranged to couple image-bearing chromatic light in the second range of field angles into the first waveguide to propagate by total internal reflection; and a second waveguide having a second input diffraction region arranged to couple image-bearing chromatic light in the first range of field angles into the second waveguide to propagate by total internal reflection, the first and second waveguides having first and second output diffraction regions (48; 50) arranged to output image-bearing chromatic light from the respective waveguides for projecting an image with said field of view towards a viewer such that the projected image appears overlaid on a real world scene 20 viewable through the waveguide assembly, characterised in that the first and second waveguides are configured, in combination, to project the colour image such that the image-bearing chromatic light may be seen by a human viewer over the full extent of said field of view for at least one wavelength within the range of wavelengths of the image-bearing chromatic light and may be seen by the human viewer over a range of field angles smaller than the full extent of said field of view for the full range of wavelengths of the image-bearing chromatic light, wherein the difference between the full extent and the range of field angles smaller than the full extent of said field of view corresponds to the peripheral vision of the human viewer and the range of field angles smaller than the full extent corresponds to the field of full colour perception of the human viewer. an image generator for generating colour images comprising image-bearing chromatic light having a range of wavelengths for injection into a waveguide assembly over a field of view comprising a first range of field angles and a second, different range of field angles, the waveguide assembly comprising: a first waveguide having a first input diffraction region arranged to couple image-bearing chromatic light in the second range of field angles into the first waveguide to propagate by total internal reflection; and a second waveguide having a second input diffraction region arranged to couple image-bearing chromatic light in the first range of field angles into the second waveguide to propagate by total internal reflection, a first waveguide having a first input diffraction region arranged to couple image-bearing chromatic light in the second range of field angles into the first waveguide to propagate by total internal reflection; and a second waveguide having a second input diffraction region arranged to couple image-bearing chromatic light in the first range of field angles into the second waveguide to propagate by total internal reflection, the first and second waveguides having first and second output diffraction regions (48; 50) arranged to output image-bearing chromatic light from the respective waveguides for projecting an image with said field of view towards a viewer such that the projected image appears overlaid on a real world scene 20 viewable through the waveguide assembly, characterised in that the first and second waveguides are configured, in combination, to project the colour image such that the image-bearing chromatic light may be seen by a human viewer over the full extent of said field of view for at least one wavelength within the range of wavelengths of the image-bearing chromatic light and may be seen by the human viewer over a range of field angles smaller than the full extent of said field of view for the full range of wavelengths of the image-bearing chromatic light, wherein the difference between the full extent and the range of field angles smaller than the full extent of said field of view corresponds to the peripheral vision of the human viewer and the range of field angles smaller than the full extent corresponds to the field of full colour perception of the human viewer.