A head-mounted display, comprising: an image light guide (10, 20, 40) including: a transmissive planar waveguide having plane-parallel inner and outer surfaces (14, 16), wherein a real-world object within an ambient environment is viewable through the image light guide (10, 20, 40); an in-coupling optic (IDO, 108) operable to direct angularly related image-bearing light beams encoding a virtual object into the waveguide from an image source (18, 106), wherein the image-bearing light beams propagate by total internal reflection, and an out-coupling optic operable to direct the propagating image-bearing light beams from the waveguide toward an eyebox (E, 38), wherein the virtual object is viewed at a first focusing distance from the eyebox (E, 38); a multifunction optic located between the inner surface of the waveguide and the eyebox (E, 38), wherein the multifunction optic is formed as a single optical element operable to provide: a) a negative optical power contribution operable to diverge the image-bearing light beams in advance of the eyebox (E, 38), such that the virtual object is viewed at a second focusing distance from the eyebox (E, 38) and the second focusing distance is closer than the first focusing distance, and b) a corrective optical contribution operable to reduce optical aberrations associated with viewing both the real-world object and the virtual object at the second focusing distance; and a positive-power optic (64, 124) located between the outer surface of the waveguide and the ambient environment, wherein the positive-power optic is operable to compensate for the negative optical power contribution of the multifunction optic without compensating for the corrective optical contribution of the multifunction optic, wherein the real-world object is viewed at its actual distance from the eyebox (E, 38) with corrected vision; characterized in that said in-coupling optic is diffractive, said out-coupling optic is diffractive, and by a lens holder configured to support the multifunction optic, wherein the lens holder is slideably removeable from the head-mounted display, and wherein the image light guide (10, 20, 40) is in fixed arrangement with the head-mounted display. an image light guide (10, 20, 40) including: a transmissive planar waveguide having plane-parallel inner and outer surfaces (14, 16), wherein a real-world object within an ambient environment is viewable through the image light guide (10, 20, 40); an in-coupling optic (IDO, 108) operable to direct angularly related image-bearing light beams encoding a virtual object into the waveguide from an image source (18, 106), wherein the image-bearing light beams propagate by total internal reflection, and an out-coupling optic operable to direct the propagating image-bearing light beams from the waveguide toward an eyebox (E, 38), wherein the virtual object is viewed at a first focusing distance from the eyebox (E, 38); a transmissive planar waveguide having plane-parallel inner and outer surfaces (14, 16), wherein a real-world object within an ambient environment is viewable through the image light guide (10, 20, 40); an in-coupling optic (IDO, 108) operable to direct angularly related image-bearing light beams encoding a virtual object into the waveguide from an image source (18, 106), wherein the image-bearing light beams propagate by total internal reflection, and an out-coupling optic operable to direct the propagating image-bearing light beams from the waveguide toward an eyebox (E, 38), wherein the virtual object is viewed at a first focusing distance from the eyebox (E, 38); a multifunction optic located between the inner surface of the waveguide and the eyebox (E, 38), wherein the multifunction optic is formed as a single optical element operable to provide: a) a negative optical power contribution operable to diverge the image-bearing light beams in advance of the eyebox (E, 38), such that the virtual object is viewed at a second focusing distance from the eyebox (E, 38) and the second focusing distance is closer than the first focusing distance, and b) a corrective optical contribution operable to reduce optical aberrations associated with viewing both the real-world object and the virtual object at the second focusing distance; and a negative optical power contribution operable to diverge the image-bearing light beams in advance of the eyebox (E, 38), such that the virtual object is viewed at a second focusing distance from the eyebox (E, 38) and the second focusing distance is closer than the first focusing distance, and b) a corrective optical contribution operable to reduce optical aberrations associated with viewing both the real-world object and the virtual object at the second focusing distance; and a positive-power optic (64, 124) located between the outer surface of the waveguide and the ambient environment, wherein the positive-power optic is operable to compensate for the negative optical power contribution of the multifunction optic without compensating for the corrective optical contribution of the multifunction optic, wherein the real-world object is viewed at its actual distance from the eyebox (E, 38) with corrected vision; characterized in that said in-coupling optic is diffractive, said out-coupling optic is diffractive, and by a lens holder configured to support the multifunction optic, wherein the lens holder is slideably removeable from the head-mounted display, and wherein the image light guide (10, 20, 40) is in fixed arrangement with the head-mounted display.