Active retroreflectors for head-mounted display tracking

Patent metadata

Field	Value
Publication number	US-2018361232-A1
Application number	US-201715784011-A
Country	US
Kind code	A1
Filing date	Oct 13, 2017
Priority date	Jun 14, 2017
Publication date	Dec 20, 2018
Grant date	—

Abstract

A head-mounted display (HMD) is provided, including: an emitter configured to emit a scanning beam into an interactive environment, the scanning beam being configured to continuously trace a predefined scan pattern; a detector configured to detect reflections of the scanning beam back to the HMD by each of a plurality of modulating retroreflectors; a processor configured to, for each detected reflection of the scanning beam, analyze the detected reflection to identify the modulating retroreflector that produced the reflection, and further determine a time at which the reflection occurred, wherein the times at which the reflections occurred and the identification of the modulating retroreflectors that produced the reflections are used to determine a location or orientation of the HMD in the interactive environment; a display device configured to render a view of a virtual space that is determined based on the determined location or orientation of the HMD.

First claim

1 . A head-mounted display (HMD), comprising:
an emitter configured to emit a scanning beam into an interactive environment in which the HMD is disposed, the scanning beam being configured to continuously trace a predefined scan pattern; a detector configured to detect reflections of the scanning beam back to the HMD by each of a plurality of modulating retroreflectors; a processor configured to, for each detected reflection of the scanning beam, analyze the detected reflection of the scanning beam to identify the modulating retroreflector that produced the reflection of the scanning beam, and further determine a time at which the reflection of the scanning beam by the identified modulating retroreflector occurred, wherein the times at which the reflections occurred and the identification of the modulating retroreflectors that produced the reflections are used to determine a location or orientation of the HMD in the interactive environment; a display device configured to render a view of a virtual space that is determined based on the determined location or orientation of the HMD.

2 . The HMD of claim 1 , wherein analyzing the detected reflection of the scanning beam includes identifying an encoding of the reflection of the scanning beam that is produced by, and correlated to, the modulating retroreflector that produced the reflection.

3 . The HMD of claim 1 , wherein the emitter includes a beam generator and a microelectromechanical system (MEMS) mirror, the beam generator configured to generate and direct the scanning beam towards the MEMS mirror, wherein the MEMS mirror is controlled to steer the scanning beam to continuously trace the predefined scan pattern.

4 . The HMD of claim 3 , wherein the predefined scan pattern is defined by a raster scan pattern or a Lissajous scan pattern.

5 . The HMD of claim 3 , wherein the scanning beam is defined by an infrared (IR) beam that is generated by the beam generator.

6 . The HMD of claim 1 , wherein each of the plurality of modulating retroreflectors is configured to reflect the scanning beam back to the HMD along a return path that is substantially parallel and substantially coincident to an emission path along which the scanning beam was emitted from the emitter.

7 . The HMD of claim 6 , wherein each of the plurality of modulating retroreflectors includes a corner reflector.

8 . The HMD of claim 1 , wherein the detector includes at least one photosensor configured to detect the reflections of the scanning beam.

9 . The HMD of claim 1 , wherein the plurality of modulating retroreflectors includes three or more modulating retroreflectors.

10 . The HMD of claim 1 , wherein determining the location or orientation of the HMD includes, for each modulating retroreflector, determining a position of the scanning beam at the time that the reflection of the scanning beam from the modulating retroreflector occurred.

11 . A system, comprising:
a plurality of modulating retroreflectors; a head-mounted display (HMD), including, an emitter configured to emit a scanning beam into an interactive environment in which the HMD is disposed, the scanning beam being configured to continuously trace a predefined scan pattern; a detector configured to detect reflections of the scanning beam back to the HMD by each of a plurality of modulating retroreflectors; a processor configured to, for each detected reflection of the scanning beam, analyze the detected reflection of the scanning beam to identify the modulating retroreflector that produced the reflection of the scanning beam, and further determine a time at which the reflection of the scanning beam by the identified modulating retroreflector occurred, wherein the times at which the reflections occurred and the identification of the modulating retroreflectors that produced the reflections are used to determine a location or orientation of the HMD in the interactive environment; a display device; a computing device, the computing device configured to generate a view of a virtual space that is determined based on the determined location or orientation of the HMD in the interactive environment; wherein the display device of the HMD is configured to render the view of the virtual space.

12 . The system of claim 11 , wherein analyzing the detected reflection of the scanning beam includes identifying an encoding of the reflection of the scanning beam that is produced by, and correlated to, the modulating retroreflector that produced the reflection.

13 . The system of claim 11 , wherein the emitter includes a beam generator and a microelectromechanical system (MEMS) mirror, the beam generator configured to generate and direct the scanning beam towards the MEMS mirror, wherein the MEMS mirror is controlled to steer the scanning beam to continuously trace the predefined scan pattern.

14 . The system of claim 11 , wherein each of the plurality of modulating retroreflectors is configured to reflect the scanning beam back to the HMD along a return path that is substantially parallel and substantially coincident to an emission path along which the scanning beam was emitted from the emitter.

15 . The system of claim 14 , wherein each of the plurality of modulating retroreflectors includes a corner reflector.

16 . The system of claim 11 , wherein the detector includes at least one photosensor configured to detect the reflections of the scanning beam.

17 . The system of claim 11 , wherein the plurality of modulating retroreflectors includes three or more modulating retroreflectors.

18 . The system of claim 10 , wherein determining the location or orientation of the HMD includes, for each modulating retroreflector, determining a position of the scanning beam at the time that the reflection of the scanning beam from the modulating retroreflector occurred.

19 . A method, comprising:
emitting, from a head-mounted display (HMD), a scanning beam into an interactive environment in which the HMD is disposed, the scanning beam being configured to continuously trace a predefined scan pattern; detecting, at the HMD, reflections of the scanning beam back to the HMD by each of a plurality of modulating retroreflectors; for each detected reflection of the scanning beam, analyzing the detected reflection of the scanning beam to identify the modulating retroreflector that produced the reflection of the scanning beam, and further determining a time at which the reflection of the scanning beam by the identified modulating retroreflector occurred, wherein the times at which the reflections occurred and the identification of the modulating retroreflectors that produced the reflections are used to determine a location or orientation of the HMD in the interactive environment; rendering through the HMD a view of a virtual space that is determined based on the determined location or orientation of the HMD.

20 . The method of claim 19 , wherein analyzing the detected reflection of the scanning beam includes identifying an encoding of the reflection of the scanning beam that is produced by, and correlated to, the modulating retroreflector that produced the reflection.

21 . The method of claim 19 , wherein the predefined scan pattern is defined by a raster scan pattern or a Lissajous scan pattern.

22 . The method of claim 19 , wherein each of the plurality of modulating retroreflectors is configured to reflect the scanning beam back to the HMD along a return path that is substantially parallel and substantially

Assignees

• Sony Interactive Entertainment Inc

Inventors

• Mallinson Dominic

Classifications

• G02B26/0833

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title

• G06F3/0346

  with detection of the device orientation or free movement in a three-dimensional [3D] space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors · CPC title

• A63F13/428

  involving motion or position input signals, e.g. signals representing the rotation of an input controller or a player's arm motions sensed by accelerometers or gyroscopes · CPC title

• G06F3/012 Primary

  Head tracking input arrangements · CPC title

• G01S17/74

  Systems using reradiation of electromagnetic waves other than radio waves, e.g. IFF, i.e. identification of friend or foe · CPC title