# US 11,079,518 B1 · Transparent tunable optical elements with structurally-modified electroactive polymer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,518 B1 - Document ID: US11079518B1 - Status: Granted - Kind: B1 - Application number: 16/288,898 - Filed: 2019-02-28 - Granted: 2021-08-03 - Earliest claimed: 2019-02-28 - Assignees: Facebook Technologies, LLC - Applicants: Facebook Technologies, LLC - Inventors: Katherine Marie Smyth; Andrew John Ouderkirk; Spencer Allan Wells - Web page: https://patentgrep.com/patent/US11079518B1 ## CPC - G02B 3/12: Fluid-filled or evacuated lenses - G02B 3/14: of variable focal length - G02B 27/0172: {characterised by optical features} - G02B 27/0955: {Lenses (lenses per se G02B3/00)} - H10N 30/04: Treatments to modify a piezoelectric or electrostrictive property, e.g. polarisation characteristics, vibration characteristics or mode tuning - H10N 30/08: Shaping or machining of piezoelectric or electrostrictive bodies - H10N 30/2048: {having non-planar shape} - H10N 30/857: Macromolecular compositions - H10N 30/87: Electrodes or interconnections, e.g. leads or terminals - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract An optical element includes a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, and a structurally-modified and transparent electroactive polymer disposed between and abutting the primary electrode and the secondary electrode. An optical device may include a tunable lens and an optical element disposed over at least one surface of the tunable lens. ## Claims ### Claim 1 An optical element comprising: a primary electrode; a secondary electrode overlapping at least a portion of the primary electrode; and a transparent, structurally-modified electroactive polymer disposed between and abutting the primary electrode and the secondary electrode; wherein a surface of the structurally-modified electroactive polymer facing at least one of the primary electrode or the secondary electrode is non-planar when zero voltage is applied between the primary electrode and the secondary electrode. ### Claim 2 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises a piezoelectric polymer or an electrostrictive polymer. ### Claim 3 (depends on 1) The optical element of claim 1, wherein the electroactive polymer comprises a PVDF homopolymer, a P(VDF-TrFE) co-polymer, a P(VDF-TrFE-CFE) ter-polymer or a P(VDF-TrFE-CTFE) ter-polymer. ### Claim 4 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises a transmissivity within the visible spectrum of at least approximately 20% and less than approximately 10% haze when the structurally-modified electroactive polymer has a thickness of between approximately 10 nm and approximately 100 μm. ### Claim 5 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises a non-zero stress state when the zero voltage is applied between the primary electrode and the secondary electrode. ### Claim 6 (depends on 1) The optical element of claim 1, further comprising a multi-layer stack including the primary electrode, the secondary electrode and the structurally-modified electroactive polymer, wherein the multi-layer stack comprises a unimorph architecture, a bi-morph architecture or a multi-morph architecture. ### Claim 7 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises particles of a nucleating agent. ### Claim 8 (depends on 7) The optical element of claim 7, wherein the particles comprise a material selected from the group consisting of graphene, carbon nanotubes, hexagonal boron nitride, and oxide nanoparticles. ### Claim 9 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer is at least partially hydrogenated. ### Claim 10 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises a molecular-level defect. ### Claim 11 (depends on 1) The optical element of claim 1, wherein the structurally-modified electroactive polymer comprises nanocrystalline domains. ### Claim 12 An optical device, comprising: a tunable lens; and a first optical element disposed over a first surface of the tunable lens, wherein the first optical element comprises: a primary electrode; a secondary electrode overlapping at least a portion of the primary electrode; and a transparent, structurally-modified electroactive polymer disposed between and abutting the primary electrode and the secondary electrode; wherein a surface of the structurally-modified electroactive polymer facing at least one of the primary electrode or the secondary electrode is non-planar when zero voltage is applied between the primary electrode and the secondary electrode. ### Claim 13 (depends on 12) The optical device of claim 12, wherein the tunable lens comprises a liquid lens. ### Claim 14 (depends on 12) The optical device of claim 12, wherein the tunable lens comprises a geometry selected from the group consisting of prismatic, freeform, plano, meniscus, bi-convex, plano-convex, bi-concave, and plano-concave. ### Claim 15 (depends on 12) The optical device of claim 12, wherein a second optical element is disposed over a second surface of the tunable lens. ### Claim 16 (depends on 12) A head mounted display comprising the optical device of claim 12, wherein the optical device is located within a transparent aperture of the head mounted display. ### Claim 17 A method comprising: forming an electroactive polymer layer over a primary electrode; structurally modifying the electroactive polymer layer; and forming a secondary electrode over the electroactive polymer layer, wherein: a surface of the structurally-modified electroactive polymer facing at least one of the primary electrode or the secondary electrode is non-planar when zero voltage is applied between the primary electrode and the secondary electrode; and structurally modifying the electroactive polymer layer comprises at least one of: applying stress to the electroactive polymer layer, incorporating particles of a filler material within the electroactive polymer, thermally annealing the electroactive polymer, hydrogenating the electroactive polymer, and irradiating the electroactive polymer layer. ### Claim 18 (depends on 17) The method of claim 17, wherein the structurally-modified electroactive polymer layer is transparent. ### Claim 19 (depends on 17) The method of claim 17, wherein the structurally-modified electroactive polymer layer and at least one of the primary electrode or the secondary electrode are formed by co-extrusion.