Planar waveguide apparatus with diffraction element(s) and system employing same

• US 9,671,566 B2
• Filed: 07/14/2014
• Issued: 06/06/2017
• Est. Priority Date: 06/11/2012
• Status: Active Grant

• Current Assignee: Magic Leap, Inc.
• Original Assignee: Magic Leap, Inc.
• Inventors: Watson, Mathew D., Abovitz, Rony, Schowengerdt, Brian T.
• Primary Examiner(s): Doan, Jennifer
• Application Number:
  US14/331,218
• Publication Number:
  US 20150016777A1
• Time in Patent Office: 1,058 Days
• Field of Search: 385 15, 385 31, 385 37, 385 39, 385129
• CPC Class Codes: G02B 27/0093 with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking
• CPC Class Codes: G02B 27/0172 characterised by optical features
• CPC Class Codes: G02B 30/26 of the autostereoscopic type
• CPC Class Codes: G02B 30/52 the 3D volume being constructed from a stack or sequence of 2D planes, e.g. depth sampling systems
• CPC Class Codes: G02B 6/34 utilising prism or grating G02B6/293 takes precedence
• CPC Class Codes: G06F 3/011 Arrangements for interaction with the human body, e.g. for user immersion in virtual reality blind teaching G09B21/00
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06F 3/0304 Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: G06F 3/0482 Interaction with lists of selectable items, e.g. menus
• CPC Class Codes: H04N 13/239 using two 2D image sensors having a relative position equal to or related to the interocular distance H04N13/243 takes precedence
• CPC Class Codes: H04N 13/344 with head-mounted left-right displays
• CPC Class Codes: H04N 13/395 with depth sampling, i.e. the volume being constructed from a stack or sequence of 2D image planes

Abstract

A waveguide apparatus includes a planar waveguide and at least one optical diffraction element (DOE) that provides a plurality of optical paths between an exterior and interior of the planar waveguide. A phase profile of the DOE may combine a linear diffraction grating with a circular lens, to shape a wave front and produce beams with desired focus. Waveguide apparati may be assembled to create multiple focal planes. The DOE may have a low diffraction efficiency, and planar waveguides may be transparent when viewed normally, allowing passage of light from an ambient environment (e.g., real world) useful in AR systems. Light may be returned for temporally sequentially passes through the planar waveguide. The DOE(s) may be fixed or may have dynamically adjustable characteristics. An optical coupler system may couple images to the waveguide apparatus from a projector, for instance a biaxially scanning cantilevered optical fiber tip.

Claims

1. A waveguide array apparatus, comprising:

a plurality of planar waveguides including

a first planar waveguide of the plurality having a first end, a second end, a first face, and a second face, the first end of the first planar waveguide opposed to the second end of the first planar waveguide along a length of the first planar waveguide, at least the first and the second faces of the first planar waveguide forming a first at least partially internally reflective optical path along at least a portion of the length of the first planar waveguide, and

a second planar waveguide of the plurality having a first end, a second end, a first face, and a second face, the first end of the second planar waveguide opposed to the second end of the second planar waveguide along a length of the second planar waveguide, at least the first and the second faces of the second planar waveguide forming a second at least partially internally reflective optical path along at least a portion of the length of the second planar waveguide,

wherein the second face of the first planar waveguide is disposed adjacent to the first face of the second planar waveguide;

a first reflector disposed adjacent respective first ends of the first and second planar waveguides; and

a second reflector disposed adjacent respective second ends of the first and second planar waveguides,

wherein the first planar waveguide has a first diffractive optical element disposed between the respective first and second ends along at least a portion of the length of the first planar waveguide to reflect a portion of a spherical wave front outwardly from the first face of the first planar waveguide, and

wherein the second planar waveguide has a second diffractive optical element disposed between the respective first and second ends along at least a portion of the length of the second planar waveguide to reflect a portion of a flat wave front outwardly from the first face of the second planar waveguide.

2. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements is integral with a respective planar waveguide.

3. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements is disposed between the first and second faces of a respective planar waveguide.

4. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements is disposed at one of the first face or second faces of a respective planar waveguide.

5. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements is a Bragg grating.

6. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements combines a linear diffraction function and a radially circular lens function.

7. The waveguide array apparatus of claim 1, wherein at least one of the respective diffractive optical elements has a phase profile that is a combination of a linear diffraction grating and a radially symmetric lens.

8. The waveguide array apparatus of claim 1, wherein the plurality of waveguides is stacked along an axis that is generally parallel to an optical axis of the waveguide apparatus to form a linear array.

9. The waveguide array apparatus of claim 1, wherein the first planar waveguide comprises a plurality of diffractive optical elements each disposed between the respective first and second ends at respective positions along at least a portion of the length of the first planar waveguide.

10. The waveguide array apparatus of claim 9, wherein the plurality of diffractive optical elements is stacked along an axis that is generally parallel to an optical axis of the waveguide apparatus to form a linear array.

11. The waveguide array apparatus of claim 1, wherein the first and second planar waveguides have respective different first and second phase maps.