Systems and methods for mixed reality

A virtual image generation system, comprising:

• a pre-pupil expansion (PPE) element configured for receiving a collimated light beam from an imaging element and splitting the collimated light beam into a set of initial out-coupled light beamlets;
• a planar optical waveguide;
• an in-coupling (IC) element configured for optically coupling the set of initial out-coupled light beamlets into the planar optical waveguide as a set of in-coupled light beamlets;
• and
• one or more diffractive elements associated with the planar optical waveguide for splitting the set of in-coupled light beamlets into a set of final out-coupled light beamlets that exit a face of the planar optical waveguide,
• wherein the one or more diffractive elements comprises an orthogonal pupil expansion (OPE) element associated with the planar optical waveguide for further splitting the set of in-coupled light beamlets into a set of orthogonal light beamlets, and an exit pupil expansion (EPE) element associated with the planar optical waveguide for splitting the set of orthogonal light beamlets into the set of final out-coupled light beamlets, and
• wherein the PPE element comprises:
• a mini-planar optical waveguide;
• a mini-OPE element associated with the mini-planar optical waveguide for splitting the collimated light beam into a set of initial orthogonal light beamlets;
• and
• a mini-EPE element associated with the mini-planar optical waveguide for splitting the set of initial orthogonal light beamlets into the set of initial out-coupled light beamlets that exit a face of the mini-planar optical waveguide.

A virtual image generation system, comprising:

• a pre-pupil expansion (PPE) element configured for receiving a collimated light beam from an imaging element and splitting the collimated light beam into a set of initial out-coupled light beamlets;
• a planar optical waveguide;
• an in-coupling (IC) element configured for optically coupling the set of initial out-coupled light beamlets into the planar optical waveguide as a set of in-coupled light beamlets;
• and
• one or more diffractive elements associated with the planar optical waveguide for splitting the set of in-coupled light beamlets into a set of final out-coupled light beamlets that exit a face of the planar optical waveguide,
• wherein the PPE element comprises a prism configured for splitting the collimated light beam into the set of in-coupled light beamlets,
• wherein the prism comprises a semi-reflective prism plane configured for splitting the collimated light beam into the set of in-coupled light beamlets, and
• wherein the prism comprises a plurality of parallel prism planes configured for splitting the collimated light beam into the set of in-coupled light beamlets, the two parallel prism planes comprising the semi-reflective prism plane.

A virtual image generation system, comprising:

• a pre-pupil expansion (PPE) element configured for receiving a collimated light beam from an imaging element and splitting the collimated light beam into a set of initial out-coupled light beamlets;
• a planar optical waveguide;
• an in-coupling (IC) element configured for optically coupling the set of initial out-coupled light beamlets into the planar optical waveguide as a set of in-coupled light beamlets;
• and
• one or more diffractive elements associated with the planar optical waveguide for splitting the set of in-coupled light beamlets into a set of final out-coupled light beamlets that exit a face of the planar optical waveguide,
• wherein the PPE element comprises a prism configured for splitting the collimated light beam into the set of in-coupled light beamlets, and
• wherein the prism comprises a first set of parallel prism planes configured for splitting the collimated light beam into a set of initial orthogonal light beamlets that are reflected in a first direction, and a second set of parallel prism planes configured for splitting the initial orthogonal light beamlets into the set of in-coupled light beamlets that are reflected in a second direction different from the first direction.

A virtual image generation system, comprising:

• a pre-pupil expansion (PPE) element configured for receiving a collimated light beam from an imaging element and splitting the collimated light beam into a set of initial out-coupled light beamlets;
• a planar optical waveguide;
• an in-coupling (IC) element configured for optically coupling the set of initial out-coupled light beamlets into the planar optical waveguide as a set of in-coupled light beamlets;
• and
• one or more diffractive elements associated with the planar optical waveguide for splitting the set of in-coupled light beamlets into a set of final out-coupled light beamlets that exit a face of the planar optical waveguide,
• wherein the PPE element comprises:
• a first planar optical waveguide assembly configured for splitting the collimated light beam into a two-dimensional array of out-coupled light beamlets that exits a face of the first planar optical waveguide assembly, the two-dimensional out-coupled light beamlet array having an inter-beamlet spacing;
• and
• a second planar optical waveguide assembly configured for splitting the two-dimensional out-coupled light beamlet array into multiple two-dimensional arrays of out-out-coupled light beamlets that exit a face of the second planar optical waveguide assembly as the set of in-coupled light beamlets, the multiple two-dimensional out-coupled light beamlet arrays being spatially offset from each other by an inter-array spacing different from the inter-beamlet spacing of the two-dimensional out-coupled light beamlet array.