Magic Leap Patent | Eyepieces For Augmented Reality Display System

Patent: Eyepieces For Augmented Reality Display System

Publication Number: 20190187474

Publication Date: 20190620

Applicants: Magic Leap

Abstract

An eyepiece waveguide for an augmented reality display system may include an optically transmissive substrate, an input coupling grating (ICG) region, a multi-directional pupil expander (MPE) region, and an exit pupil expander (EPE) region. The ICG region may receive an input beam of light and couple the input beam into the substrate as a guided beam. The MPE region may include a plurality of diffractive features which exhibit periodicity along at least a first axis of periodicity and a second axis of periodicity. The MPE region may be positioned to receive the guided beam from the ICG region and to diffract it in a plurality of directions to create a plurality of diffracted beams. The EPE region may be positioned to receive one or more of the diffracted beams from the MPE region and to out couple them from the optically transmissive substrate as output beams.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/599,663, filed Dec. 15, 2017, and entitled “EYEPIECES FOR AUGMENTED REALITY DISPLAY SYSTEM,” and to U.S. Provisional Patent Application No. 62/608,555, filed Dec. 20, 2017, and entitled “EYEPIECES FOR AUGMENTED REALITY DISPLAY SYSTEM,” and to U.S. Provisional Patent Application No. 62/620,465, filed Jan. 22, 2018, and entitled “EYEPIECES FOR AUGMENTED REALITY DISPLAY SYSTEM.” Any and all applications for which a foreign or domestic priority claim is identified above and/or in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57.

BACKGROUND

Field

[0002] This disclosure relates to eyepieces for virtual reality, augmented reality, and mixed reality systems.

Description of the Related Art

[0003] Modern computing and display technologies have facilitated the development of virtual reality, augmented reality, and mixed reality systems. Virtual reality, or “VR,” systems create a simulated environment for a user to experience. This can be done by presenting computer-generated image data to the user through a head-mounted display. This image data creates a sensory experience which immerses the user in the simulated environment. A virtual reality scenario typically involves presentation of only computer-generated image data rather than also including actual real-world image data. Augmented reality systems generally supplement a real-world environment with simulated elements. For example, augmented reality, or “AR,” systems may provide a user with a view of the surrounding real-world environment via a head-mounted display. However, computer-generated image data can also be presented on the display to enhance the real-world environment. This computer-generated image data can include elements which are contextually-related to the real-world environment. Such elements can include simulated text, images, objects, etc. Mixed reality, or “MR,” systems are a type of AR system which also introduce simulated objects into a real-world environment, but these objects typically feature a greater degree of interactivity. The simulated elements can often times be interactive in real time.

[0004] FIG. 1 depicts an example AR scene 1 where a user sees a real-world park setting 6 featuring people, trees, buildings in the background, and a concrete platform 20. In addition to these items, computer-generated image data is also presented to the user. The computer-generated image data can include, for example, a robot statue 10 standing upon the real-world platform 20, and a cartoon-like avatar character 2 flying by which seems to be a personification of a bumblebee, even though these elements 2, 10 are not actually present in the real-world environment.

SUMMARY

[0005] In some embodiments, an eyepiece waveguide for an augmented reality display system comprises: an optically transmissive substrate; an input coupling grating (ICG) region formed on or in the substrate, the ICG region being configured to receive an input beam of light and to couple the input beam into the substrate as a guided beam; a multi-directional pupil expander (MPE) region formed on or in the substrate, the MPE region comprising a plurality of diffractive features which exhibit periodicity along at least a first axis of periodicity and a second axis of periodicity, the MPE region being positioned to receive the guided beam from the ICG region and to diffract it in a plurality of directions to create a plurality of diffracted beams; and an exit pupil expander (EPE) region formed on or in the substrate, the EPE region being positioned to receive one or more of the diffracted beams from the MPE region and to out couple them from the optically transmissive substrate as output beams.

[0006] In some embodiments, an eyepiece waveguide for an augmented reality display system comprises: an optically transmissive substrate; an input coupling grating (ICG) region formed on or in the substrate, the ICG region being configured to receive a set of input beams of light and to couple the set of input beams into the substrate as a set of guided beams, the set of guided beams being associated with a set of k-vectors in k-space which at least partially lies in a k-space annulus associated with the eyepiece waveguide, the k-space annulus corresponding to a region in k-space associated with guided propagation in the eyepiece waveguide; a multi-directional pupil expander (MPE) region formed on or in the substrate, the MPE region being positioned to receive the set of guided beams from the ICG region and being configured to diffract the set of guided beams so as to create at least three sets of diffracted beams, the sets of diffracted beams being associated with at least three sets of k-vectors which at least partially lie in the k-space annulus and are centered at three different angular locations; and an exit pupil expander (EPE) region formed on or in the substrate, the EPE region being positioned to receive one of the sets of diffracted beams from the MPE region and to out couple them from the optically transmissive substrate as output beams.

[0007] In some embodiments, an eyepiece waveguide for an augmented reality display system comprises: an input coupling region to receive input beams of light associated with an image, the input beams of light having an associated pupil; a multi-direction pupil expander (MPE) region configured to expand the pupil in at least three directions; and an exit region to project output beams of light associated with the image.

[0008] In some embodiments, an eyepiece waveguide for an augmented reality display system comprises: an optically transmissive substrate; an input coupling grating (ICG) region formed on or in the substrate, the ICG region being configured to: receive a set of input beams of light, the set of input beams being associated with a set of k-vectors in k-space; diffract the set of input beams so as to create a first guided set of beams and a first non-diffracted set of beams, the first guided set of beams corresponding to a translated subset of the k-vectors which lies inside a k-space annulus associated with the eyepiece waveguide, and the first non-diffracted set of beams corresponding to a translated subset of the k-vectors which lies outside the k-space annulus, the k-space annulus corresponding to a region in k-space associated with guided propagation in the eyepiece waveguide; diffract the set of input beams so as to create a separate second guided set of beams and a separate second non-diffracted set of beams, the second guided set of beams corresponding to a translated subset of the k-vectors which lies inside the k-space annulus, and the second non-diffracted set of beams corresponding to a translated subset of the k-vectors which lies outside the k-space annulus; a first pupil expander region formed on or in the substrate, the first pupil expander region being positioned to receive the first guided set of beams from the ICG region and being configured to replicate them as a first set of replicated beams; a second pupil expander region formed on or in the substrate, the second pupil expander region being positioned to receive the second guided set of beams from the ICG region and being configured to replicate them as a second set of replicated beams; and an exit region formed on or in the substrate, the exit region being positioned to receive the first and second sets of replicated beams, and the exit region being configured to out couple them as output beams, wherein the output beams represent the complete set of input beams.

[0009] In some embodiments, an eyepiece waveguide for an augmented reality display system comprises