Beam angle sensor in virtual/augmented reality system

• US 10,520,737 B2
• Filed: 06/11/2019
• Issued: 12/31/2019
• Est. Priority Date: 01/12/2016
• Status: Active Grant

• Current Assignee: Magic Leap, Inc.
• Original Assignee: Magic Leap, Inc.
• Inventors: Yeoh, Ivan L., Edwin, Lionel Ernest, Tekolste, Robert Dale
• Primary Examiner(s): Mushambo, Martin
• Application Number:
  US16/437,229
• Publication Number:
  US 20190293941A1
• Time in Patent Office: 203 Days
• Field of Search: None
• CPC Class Codes: G01B 11/272 using photoelectric detection means
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 26/103 having movable or deformable optical fibres, light guides or waveguides as scanning elements light guides per se G02B6/00
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• 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 27/0179 Display position adjusting means not related to the information to be displayed
• CPC Class Codes: G02B 6/0013 Means for improving the coupling-in of light from the light source into the light guide coupling light into light guides in general G02B6/42
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/34 utilising prism or grating G02B6/293 takes precedence
• CPC Class Codes: G06F 3/002 Specific input/output arrangements not covered by G06F3/01 - G06F3/16 other optical apparatus G02B27/00
• 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 3/012 Head tracking input arrangements
• CPC Class Codes: G06T 15/50 Lighting effects
• CPC Class Codes: G06T 19/006 Mixed reality object pose determination, tracking or camera calibration for mixed reality G06T7/00

Abstract

A virtual image generation system for use by an end user comprises a projection subsystem configured for generating a collimated light beam, and a display configured emitting light rays in response to the collimated light beam to display a pixel of an image frame to the end user. The pixel has a location encoded with angles of the emitted light rays. The virtual image generation system further comprises a sensing assembly configured for sensing at least one parameter indicative of at least one of the emitted light ray angles, and a control subsystem configured for generating image data defining a location of the pixel, and controlling an angle of the light beam relative to the display based on the defined location of the pixel and the sensed parameter(s).

Claims

1. A display system comprising:

a projection assembly configured to emit light;

a waveguide apparatus;

an in-coupling optical element configured to in-couple light from the projection assembly into the waveguide apparatus;

an out-coupling optical element configured to couple light from the projection assembly guided within the waveguide apparatus out of the waveguide apparatus;

a sensing assembly optically coupled to the out-coupling optical element and configured to measure at least one parameter of light incident thereon; and

a control subsystem in communication with the projection assembly and the sensing assembly, the control subsystem configured to;

cause the projection assembly to emit light corresponding to a pixel at a particular position within an image frame;

receive measurement data from the sensing assembly indicating at least one parameter of light corresponding to the pixel of the image frame; and

control operation of the projection assembly based at least in part on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly.

2. The display system of claim 1, wherein the out-coupling optical element is configured to direct at least a portion of light from the projection assembly guided within the waveguide apparatus out of the waveguide apparatus to an eye of a user of the display system.

3. The display system of claim 2, wherein the out-coupling optical element comprises an exit pupil expansion (EPE) element configured to split light from the projection assembly guided within the waveguide apparatus into multiple light rays.

4. The display system of claim 1, wherein the sensing assembly is positioned outside of a field of view (FOV) of a user of the display system.

5. The display system of claim 1 further comprising:

an exit pupil expansion (EPE) element configured to split light from the projection assembly guided within the waveguide apparatus into multiple light rays that exit the waveguide apparatus and are directed to an eye of the user of the display system.

6. The display system of claim 1 further comprising a frame structure configured to be worn about a head of a user of the display system, wherein the frame structure carries the waveguide apparatus.

7. The display system of claim 1, wherein the out-coupling optical element is configured to split light from the projection assembly guided within the waveguide apparatus into multiple light rays that exit the waveguide apparatus.

8. The display system of claim 7, wherein the out-coupling optical element comprises a linear diffraction pattern configured to split light from the projection assembly guided within the waveguide apparatus into multiple substantially-parallel light rays that exit the waveguide apparatus.

9. The display system of claim 1, wherein the control subsystem is further configured to:

determine, based on the measurement data received from the sensing assembly, an angle at which light corresponding to the pixel of the image frame is incident the sensing assembly, wherein to control operation of the projection assembly based at least in part on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly, the control subsystem is configured to;

control operation of the projection assembly based at least in part on the determined angle and an angle corresponding to the particular position of the pixel within the image frame.

10. The display system of claim 9, wherein the control subsystem is further configured to:

compute a discrepancy between the determined angle and the angle corresponding to the particular position of the pixel within the image frame,

wherein to control operation of the projection assembly based at least in part on the determined angle and the angle corresponding to the particular position of the pixel within the image frame the control subsystem is configured to;

control operation of the projection assembly based at least in part on the computed discrepancy.

11. The display system of claim 1, wherein to control operation of the projection assembly based on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly, the control subsystem is configured to:

generate one or more additional image frames based at least in part on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly and cause the projection assembly to emit light corresponding to pixels of the one or more additional image frames generated by the control subsystem.

12. The display system of claim 1, wherein to control operation of the projection assembly based on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly, the control subsystem is configured to:

control an angle at which the projection assembly emits light relative to the in-coupling optical element based at least in part on the particular position of the pixel within the image frame and the measurement data received from the sensing assembly.