Low-stress waveguide mounting for head-mounted display device

1. A waveguide assembly for a head-mounted display device, the waveguide assembly comprising:

a waveguide carrier including

a central portion, and

flat left and right mounting surfaces extending from the central portion, to align with a left eye and a right eye, respectively, of a user of the head-mounted display device;

a first left waveguide affixed to the left mounting surface of the waveguide carrier only by a first layer of adhesive contacting only a periphery of a surface of the first left waveguide; and

a first right waveguide affixed to the right mounting surface of the waveguide carrier only by a second layer of the adhesive contacting only a periphery of a surface of the first right waveguide.

2. The waveguide assembly of claim 1 , wherein the adhesive is a malleable pressure sensitive adhesive.

3. The waveguide assembly of claim 1 , wherein:

the first layer of adhesive maintains a gap between the first left waveguide and the left mounting surface of the waveguide carrier; and

the second layer of adhesive maintains a gap between the first right waveguide and the right mounting surface of the waveguide carrier.

4. The waveguide assembly of claim 1 , wherein the central portion has a surface configured to be attached to a support structure in the head-mounted display device.

5. The waveguide assembly of claim 1 , wherein the waveguide assembly is configured to be mounted within the head-mounted display device by attachment of the waveguide assembly to a support structure only at the central portion of the waveguide assembly.

6. The waveguide assembly of claim 1 , further comprising:

a second left waveguide affixed to the first left waveguide only by a third layer of the adhesive disposed between the first and second left waveguides contacting only a periphery of the first and second left waveguides; and

a second right waveguide affixed to the first right waveguide only by a fourth layer of the adhesive disposed between the first and second right waveguides.

7. The waveguide assembly of claim 6 , wherein:

the third layer of the adhesive contacts only a periphery of a surface of the second left waveguide; and

the fourth layer of the adhesive contacts only a periphery of a surface of the second right waveguide.

8. The waveguide assembly of claim 6 , further comprising:

a third left waveguide affixed to the second left waveguide only by a fifth layer of the adhesive disposed between the second and third left waveguides; and

a third right waveguide affixed to the second right waveguide only by a sixth layer of the adhesive disposed between the second and third right waveguides.

9. The waveguide assembly of claim 8 , wherein:

the first left and right waveguides each correspond to a first primary color of an additive color scheme;

the second left and right waveguides each correspond to a second primary color of the additive color scheme; and

the third left and right waveguides each correspond to a third primary color of the additive color scheme.

10. The waveguide assembly of claim 8 , wherein:

the first layer of adhesive maintains an air gap between the first left waveguide and the left mounting surface of the waveguide carrier;

the second layer of adhesive maintains an air gap between the first right waveguide and the right mounting surface of the waveguide carrier;

the third layer of adhesive maintains an air gap between the second left waveguide and the first left waveguide;

the fourth layer of adhesive maintains an air gap between the second right waveguide and the first right waveguide;

the fifth layer of adhesive maintains an air gap between the third left waveguide and the second left waveguide; and

the sixth layer of adhesive maintains an air gap between the third right waveguide and the second right waveguide.

11. The waveguide assembly of claim 1 , wherein the first left waveguide and first right waveguide each provide total internal reflection of light and include surface refractive grating.

12. A head-mounted display device comprising:

a head fitting by which the head-mounted display device can be worn on the head of a user;

a chassis coupled to the head fitting; and

a waveguide assembly including

a waveguide carrier, the waveguide carrier including:

a nose bridge portion by which the waveguide assembly is mounted to the chassis only through the central bridge, and

flat left and right mounting surfaces extending from opposite sides of the nose bridge portion; and

a first left waveguide mounted to the left mounting surface of the waveguide carrier only by a first layer of adhesive disposed around a periphery of a surface of the first left waveguide, the first layer of adhesive disposed so as to maintain an air gap between the surface of the first left waveguide and the left mounting surface of the waveguide carrier; and

a first right waveguide mounted to the right mounting surface of the waveguide carrier only by a second layer of the adhesive disposed around a periphery of a surface of the first right waveguide, the second layer of adhesive maintains an air gap between the surface of the first right waveguide and the right mounting surface of the waveguide carrier.

13. The head-mounted display device of claim 12 , further comprising:

a display assembly including left and right light emitters arranged to emit light for transmission to a left eye and a right eye, respectively, of the user, the display assembly being mounted to the chassis only through the nose bridge portion.

14. The head-mounted display device of claim 12 , wherein the adhesive is a malleable pressure sensitive adhesive.

15. The head-mounted display device of claim 14 , wherein the surface of the nose bridge portion comprises a through-hole configured to receive a fastener to couple the waveguide assembly to the support structure.

16. The head-mounted display device of claim 12 , further comprising:

a second left waveguide affixed to the first left waveguide only by a third layer of the adhesive disposed between the first and second left waveguides; and

a second right waveguide affixed to the first right waveguide only by a fourth layer of the adhesive disposed between the first and second right waveguides.

17. The head-mounted display device of claim 16 , wherein:

the third layer of the adhesive is disposed only around a periphery of a surface of the second left waveguide; and

the fourth layer of the adhesive is disposed only around a periphery of a surface of the second right waveguide.

18. The head-mounted display device of claim 16 , further comprising:

a third left waveguide affixed to the second left waveguide only by a fifth layer of the adhesive disposed between the second and third left waveguides; and

a third right waveguide affixed to the second right waveguide only by a sixth layer of the adhesive disposed between the second and third right waveguides.

19. The head-mounted display device of claim 18 , wherein:

the first left and right waveguides are each formed to transmit light of only a first primary color of an additive color scheme;

the second left and right waveguides are each formed to transmit light of only a second primary color of the additive color scheme; and

the third left and right waveguides are each formed to transmit light of only a third primary color of the additive color scheme.

20. The head-mounted display device of claim 12 , wherein the first left waveguide and first right waveguide each provide total internal reflection of light and include surface refractive grating.