Thermal dissipation for wearable device

Patent metadata

Field	Value
Publication number	US-10267970-B2
Application number	US-201715683638-A
Country	US
Kind code	B2
Filing date	Aug 22, 2017
Priority date	Aug 22, 2016
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

A thermal monitoring and dissipation system for use with an optical device is described. The optical device includes the following: a frame defining a pair of eye openings and including a pair of arms configured to extend over the ears of a user of the optical device; a temperature monitoring system configured to monitor a distribution of heat within the frame; a display assembly configured to display content to a user of the optical device; and a processor configured to receive temperature data from the temperature monitoring system and to adjust an output of the display assembly based on variation in the distribution of heat within the frame.

First claim

What is claimed is:

1. An optical device comprising:
a display assembly configured to display content to a user of the optical device;
a frame defining a pair of eye openings and being configured to position the display assembly in front of the eyes of a user of the optical device;
a temperature monitoring system configured to monitor a distribution of heat within the frame; and

a processor configured to receive temperature data from the temperature monitoring system and to adjust an output of the display assembly by spatially shifting a position of content displayed by the display assembly in accordance with changes in a distribution of heat within the frame.

2. The optical device of claim 1 , wherein the display assembly comprises one or more projectors and diffractive optics configured to both receive light from the one or more projectors and redirect the received light toward the eyes of the user of the optical device.

3. The optical device of claim 2 , wherein the output of the display assembly is spatially shifted by spatially shifting the position of content emitted from the one or more projectors by an amount equivalent to one or more pixels.

4. The optical device of claim 2 , wherein the processor is configured to adjust the output of the displayed content to accommodate for a change in shape of the frame resulting from a change in the distribution of heat within the frame.

5. The optical device of claim 2 , further comprising one or more strain gauges distributed across the frame and wherein shifting the position of the content displayed by the display assembly is also performed in accordance with measurements made by the strain gauges.

6. The optical device of claim 1 , further comprising a plurality of optical sensors mounted to the frame, wherein the processor is configured to shut down one or more of the optical sensors when a portion of the frame associated with a respective optical sensor of the plurality of optical sensors exceeds a predetermined temperature threshold.

7. The optical device of claim 1 , further comprising a plurality of optical sensors mounted to the frame, wherein the spatial shifting of the position of the content is performed in response to sensor data from the temperature monitoring system showing changes in the distribution of heat within the frame corresponding to an out of alignment condition for one or more of the plurality of optical sensors.

8. An optical device comprising:
a frame assembly and defining a first eye opening and a second eye opening;
first and second projectors coupled to the frame assembly;
diffractive optics configured to receive light emitted by the first and second projectors and orient the light toward the eyes of a user;
a temperature monitoring system; and
a processor configured to spatially shift content projected by the first and second projectors in accordance with a thermal profile of the optical device measured by the temperature monitoring system.

9. The optical device of claim 8 , wherein the frame assembly comprises a first frame and a second frame that is substantially more rigid than the first frame.

10. The optical device of claim 9 , wherein the second frame is configured to stay substantially rigid to maintain a fixed position of the first and second eye openings relative to one another and to the first and second projectors and wherein the first frame is more flexible than the second frame.

11. The optical device of claim 9 , wherein the processor is configured to spatially shift the content in response to the thermal profile indicating a misalignment between the first projector and the diffractive optics.

12. The optical device of claim 8 , wherein the first and second eye openings are positioned between the first and second projectors.

13. An optical device comprising:
a display assembly;
a frame assembly coupled to the display assembly and configured to position the display assembly in front of the eyes of a user of the optical device;

a plurality of electronic devices in thermal contact with the frame assembly; and
a processor configured to adjust operation of the display assembly by spatially shifting a position of content displayed by the display assembly in accordance with temperature changes of the frame assembly.

14. The optical device of claim 13 , wherein the frame assembly comprises a pair of arms joined together by a front band and an optics frame supporting the display assembly, the optics frame being coupled to an interior facing surface of the front band.

15. The optical device of claim 14 , wherein the front band is coupled to the optics frame by a heat transferring layer conforming to a surface of the optics frame and a surface of the front band, the heat transferring layer being configured to transfer heat from the plurality of electronic devices mounted on the optics frame to the front band.

16. The optical device of claim 15 , wherein the display assembly comprises a pair of projectors configured to project visual content into eyepieces coupled to the optics frame.

17. The optical device of claim 16 , further comprising:
a temperature sensor; and
eyepieces disposed within frame openings of the optics frame,
wherein the pair of projectors are configured to adjust an angle at which the visual content is projected into the eyepieces in accordance with temperature data provided by the temperature sensor.

18. The optical device of claim 16 , further comprising a heat distribution system including heat spreaders that distribute heat generated by the pair of projectors across respective ones of the pair of arms.

19. The optical device of claim 14 , further comprising a heat distribution system including graphite sheets affixed to interior surfaces of the pair of arms.

20. The optical device of claim 14 , wherein the pair of arms comprises a first arm fixedly coupled to the front band and a second arm flexibly coupled to the front band and configured to bend and flex to accommodate physiological features of the user.

Assignees

• Magic Leap Inc

Inventors

• Jones Jr William K
• Greco Paul M
• Schabacker Charles Robert

Classifications

• G02B7/008

  with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation · CPC title

• G02B6/29325

  of the slab or planar or plate like form, i.e. confinement in a single transverse dimension only (integrated circuit planar waveguide arrangements G02B6/12007; specially adapted for lighting G02B6/0011) · CPC title

• G02B6/34

  utilising prism or grating {(G02B6/293 takes precedence)} · CPC title

• G02B27/017 Primary

  Head mounted · CPC title

• G09G3/002

  to project the image of a two-dimensional display, such as an array of light emitting or modulating elements or a CRT · CPC title