An imaging apparatus (200, 300) for forming a virtual image (V1, V2), comprising: a planar waveguide having first and second plane-parallel surfaces; an in-coupling diffractive optic arranged to direct image-bearing light beams into the waveguide; and an out-coupling diffractive optic arranged to direct the image-bearing light beams from the waveguide toward an eyebox (74, E), wherein the waveguide is configured to propagate the image-bearing light beams from the in-coupling diffractive optic to the out-coupling diffractive optic as a set of angularly related collimated beams, the out-coupling diffractive optic having a two-dimensional array of contiguous diffractive zones, wherein each of the diffractive zones comprises a set of diffractive features, and the diffractive features in each set have a common orientation and a common pitch; a succession of the zones along a first dimension of the array having respective sets of diffractive features that progressively vary in pitch in a stepwise manner, wherein the sets of diffractive features in the successive zones along the first dimension are oriented in a common direction; a succession of the zones along a second dimension of the array having respective sets of diffractive features that progressively vary in orientation in a stepwise manner, wherein the pitch of the diffractive features is constant along the second dimension of the array; and wherein the successions of zones along the first and second dimensions of the array are configured to convert each of the collimated beams into a diverging beam that appears to emanate from a near focus spot on an opposite side of the planar waveguide as viewed within the eyebox (74, E). a planar waveguide having first and second plane-parallel surfaces; an in-coupling diffractive optic arranged to direct image-bearing light beams into the waveguide; and an out-coupling diffractive optic arranged to direct the image-bearing light beams from the waveguide toward an eyebox (74, E), wherein the waveguide is configured to propagate the image-bearing light beams from the in-coupling diffractive optic to the out-coupling diffractive optic as a set of angularly related collimated beams, the out-coupling diffractive optic having a two-dimensional array of contiguous diffractive zones, wherein each of the diffractive zones comprises a set of diffractive features, and the diffractive features in each set have a common orientation and a common pitch; wherein the waveguide is configured to propagate the image-bearing light beams from the in-coupling diffractive optic to the out-coupling diffractive optic as a set of angularly related collimated beams, the out-coupling diffractive optic having a two-dimensional array of contiguous diffractive zones, wherein each of the diffractive zones comprises a set of diffractive features, and the diffractive features in each set have a common orientation and a common pitch; a succession of the zones along a first dimension of the array having respective sets of diffractive features that progressively vary in pitch in a stepwise manner, wherein the sets of diffractive features in the successive zones along the first dimension are oriented in a common direction; a succession of the zones along a second dimension of the array having respective sets of diffractive features that progressively vary in orientation in a stepwise manner, wherein the pitch of the diffractive features is constant along the second dimension of the array; and wherein the successions of zones along the first and second dimensions of the array are configured to convert each of the collimated beams into a diverging beam that appears to emanate from a near focus spot on an opposite side of the planar waveguide as viewed within the eyebox (74, E).