An augmented reality device, comprising: a waveguide (306; 406; 506); an input diffractive optical element (301; 401; 501) positioned in or on the waveguide configured to receive light from a projector and to couple the light into the waveguide so that it is captured within the waveguide by total internal reflection; an output diffractive optical element (304; 404; 504) positioned in or on the waveguide configured to couple totally internally reflected light out of the waveguide towards a viewer; and a returning diffractive optical element (307, 309; 407, 409; 507, 509) positioned in or on the waveguide configured to receive light from the output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element; characterised in that the output diffractive optical element comprises first and second output diffractive optical elements overlaid on one another in or on the waveguide, wherein the first output diffractive optical element is configured to receive light from an input direction and couple it towards the second output diffractive optical element which can then provide outcoupled orders towards a viewer, and the second output diffractive optical element is configured to receive light from an input direction and couple it towards the first output diffractive optical element which can then provide outcoupled orders towards a viewer; wherein the augmented reality device further comprises first and second returning diffractive optical elements (307, 309; 407, 409; 507, 509), wherein the first returning diffractive optical element (307; 407; 507) is positioned to receive light from the first output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element which can then provide outcoupled orders towards a viewer, and wherein the second returning diffractive optical element (309; 409; 509) is positioned to receive light from the second output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element which can then provide outcoupled orders towards a viewer. a waveguide (306; 406; 506); an input diffractive optical element (301; 401; 501) positioned in or on the waveguide configured to receive light from a projector and to couple the light into the waveguide so that it is captured within the waveguide by total internal reflection; an output diffractive optical element (304; 404; 504) positioned in or on the waveguide configured to couple totally internally reflected light out of the waveguide towards a viewer; and a returning diffractive optical element (307, 309; 407, 409; 507, 509) positioned in or on the waveguide configured to receive light from the output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element; characterised in that the output diffractive optical element comprises first and second output diffractive optical elements overlaid on one another in or on the waveguide, wherein the first output diffractive optical element is configured to receive light from an input direction and couple it towards the second output diffractive optical element which can then provide outcoupled orders towards a viewer, and the second output diffractive optical element is configured to receive light from an input direction and couple it towards the first output diffractive optical element which can then provide outcoupled orders towards a viewer; wherein the augmented reality device further comprises first and second returning diffractive optical elements (307, 309; 407, 409; 507, 509), wherein the first returning diffractive optical element (307; 407; 507) is positioned to receive light from the first output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element which can then provide outcoupled orders towards a viewer, and wherein the second returning diffractive optical element (309; 409; 509) is positioned to receive light from the second output diffractive optical element and to diffract the received light so that it is returned towards the output diffractive optical element which can then provide outcoupled orders towards a viewer.