Optical lens assemblies, head-mounted displays, and related methods

1. An optical lens assembly, comprising:

a deformable optical element comprising:

a substantially transparent transducer configured to deform, and thus change at least one optical property of, the deformable optical element; and

a structural support element supporting the substantially transparent transducer;

wherein the structural support element comprises an eye-tracking element configured to facilitate tracking a user's eye;

wherein at least a portion of the substantially transparent transducer is positioned within a substantially transparent optical aperture of the optical lens assembly; and

wherein the substantially transparent transducer comprises an electroactive material.

2. The optical lens assembly of claim 1 , wherein the substantially transparent optical aperture allows the passage of light to a user's eye.

3. The optical lens assembly of claim 1 , wherein at least one of the optical lens assembly or the deformable optical element has a non-symmetric shape.

4. The optical lens assembly of claim 1 , wherein the substantially transparent transducer further comprises an electromechanical element.

5. The optical lens assembly of claim 1 , wherein the electroactive material further comprises at least one of a piezoelectric ceramic or an electrostrictor ceramic.

6. The optical lens assembly of claim 5 , wherein the electroactive material comprises a polycrystalline ceramic material.

7. The optical lens assembly of claim 6 , wherein the polycrystalline ceramic material includes a dopant.

8. The optical lens assembly of claim 5 , wherein the electroactive material has a perovskite-type crystallography.

9. The optical lens assembly of claim 1 , wherein the electroactive material further comprises at least one of an electrostrictor polymer, a dielectric elastomer, or an ionic polymer conductor.

10. The optical lens assembly of claim 1 , wherein the electroactive material further comprises a single-crystal material.

11. The optical lens assembly of claim 10 , wherein the single-crystal material comprises at least one of K 0.5 Na 0.5 NbO 3 , barium titanate, lithium niobate, lithium tetraborate, quartz, Pb(Mg 1/3 Nb 2/3 )O 3 —PbTiO 3 , or Pb(Zn 1/3 Nb 2/3 )O 3 —PbTiO 3 .

12. The optical lens assembly of claim 1 , wherein the substantially transparent transducer further comprises at least one substantially transparent electrode configured to activate the electroactive material by application of an electrical voltage thereto.

13. The optical lens assembly of claim 1 , wherein:

the substantially transparent transducer comprises:

a first surface and an opposing second surface; and

at least one first electrode electrically coupled to the first surface and at least one second electrode electrically coupled to the second surface; and

one or more of the first electrode and the second electrode comprises at least one of a transparent conducting oxide, indium tin oxide, a nanocomposite material, carbon nanotubes, silver nanowires, or graphene.

14. The optical lens assembly of claim 13 , further comprising a driving circuit electrically coupled to the first electrode and the second electrode.

15. The optical lens assembly of claim 1 , wherein the substantially transparent transducer comprises a material having an elastic modulus greater than approximately 5 GPa.

16. The optical lens assembly of claim 1 , wherein the structural support element comprises a substantially zero optical power lens or a substantially non-zero optical power lens.

17. The optical lens assembly of claim 1 , wherein the optical property comprises at least one of an accommodative optical property or an adaptive optical property.

18. The optical lens assembly of claim 1 , wherein the deformable optical element further comprises a deformable medium comprising at least one of a liquid, a gas, a gel, a foam, or a polymer.

19. The optical lens assembly of claim 18 , wherein the deformable medium is contained within the optical lens assembly by at least one of:

a rigid seal;

a semi-rigid seal;

a flexible seal; or

a frame of the optical lens assembly.

20. The optical lens assembly of claim 18 , wherein the deformable medium is formed of a material that does not require an edge seal.

21. The optical lens assembly of claim 1 , wherein the substantially transparent transducer comprises at least two electroactive materials.

22. The optical lens assembly of claim 21 , wherein:

the two electroactive materials comprise more than two electroactive materials; and

the optical lens assembly further comprises a series driving circuit or a parallel driving circuit electrically coupled to the more than two electroactive materials.

23. The optical lens assembly of claim 1 , wherein the electroactive material is coupled to at least one electrically passive support material.

24. The optical lens assembly of claim 23 , wherein the electrically passive support material has a higher mechanical stiffness than the electroactive material.

25. The optical lens assembly of claim 1 , wherein the electroactive material of the substantially transparent transducer comprises a piezoelectric polymer including at least one of polyvinylidene fluoride or a copolymer of polyvinylidene fluoride.

26. A head-mounted display, comprising:

a display element;

an optical lens assembly that, when the head-mounted display is worn by a user, is positioned between the display element and an eye of the user, wherein the optical lens assembly comprises:

at least one deformable optical element comprising at least one substantially transparent transducer positioned at least partially within a substantially transparent optical aperture of the optical lens assembly; and

an additional optical lens assembly positioned adjacent the display element on a side opposite the optical lens assembly, wherein the additional optical lens assembly comprises an additional deformable optical element;

wherein the substantially transparent transducer is configured to deform, and thus change at least one optical property of, the deformable optical element.

27. A method of fabricating an optical lens assembly, comprising:

forming a deformable optical element that comprises a substantially transparent transducer;

forming at least a portion of at least one layer within the substantially transparent transducer via:

extruding a billet of at least one electroactive polymer material to thin the electroactive polymer material; and

prior to or after the extrusion, coupling a conductive electrode material to the electroactive polymer material; and

positioning at least a portion of the substantially transparent transducer within a transparent optical aperture of the optical lens assembly;

wherein the substantially transparent transducer is configured to deform, and thus change at least one optical property of, the deformable optical element.

28. The method of claim 27 , wherein forming the substantially transparent transducer comprises:

growing a single-crystal material;

cutting the single-crystal material at a predetermined angle relative to a crystalline structure thereof;

thinning the cut single-crystal material; and

forming a transparent, electrically conductive material over the thinned single-crystal material.

29. The method of claim 27 , wherein forming the substantially transparent transducer comprises:

hot-pressing a powdered ceramic material without a dopant; or

hot-pressing a powdered ceramic material with a dopant.

30. The method of claim 29 , further comprising:

forming the powdered ceramic material; and

forming a green body prior to hot-pressing the powdered ceramic material.

31. The method of claim 27 , further comprising electrically coupling a driving circuit to the substantially transparent transducer.

32. The optical lens assembly of claim 27 , wherein the forming the at least a portion of the at least one layer within the substantially transparent transducer further comprises at least one of:

chemical vapor deposition;

physical vapor deposition;

transfer processing;

hot-pressing a powdered ceramic material without a dopant;

hot-pressing a powdered ceramic material with a dopant; or

solvent evaporation.