# US 10,371,870 B2 · Variable focus lens > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,870 B2 - Document ID: US10371870B2 - Status: Granted - Kind: B2 - Application number: 15/561,054 - Filed: 2016-03-24 - Published: 2018-03-15 - Granted: 2019-08-06 - Earliest claimed: 2016-03-24 - Assignees: Optotune AG - Applicants: Optotune AG - Inventors: Manuel Aschwanden; David Niederer; Philipp Waibel - Web page: https://patentgrep.com/patent/US10371870B2 ## CPC - G02B 3/14: of variable focal length - G02B 7/10: by relative axial movement of several lenses, e.g. of varifocal objective lens - G02B 7/182: for mirrors - G02B 26/005: {based on electrowetting} - A61B 1/0019: {characterised by variable lenses} - G02C 7/085: {Fluid-filled lenses, e.g. electro-wetting lenses} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G02C: SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES (trial frames for testing the eyes A61B3/04; goggles or eyeshields not having the same features as spectacles A61F9/00) ## Abstract The invention relates to a variable focus lens comprising an elastically deformable optical element (7) and a circumferential mechanism (10, 1, 5, 2, 3, 8, 21) to transfer a rotational movement to an axial movement, wherein by using a ball bearing system (9, 11, 12, 13, 15, 16, 17) the mechanism is optimized in a manner to reduce mechanical friction, friction variation and to improve force-direction dependent positioning insensitivity. ## Claims ### Claim 1 A variable focus lens comprising an elastically deformable optical element (7) and a circumferential mechanism (10, 1, 5, 2, 3, 8, 21) to transfer a rotational movement to an axial movement, wherein by using a ball bearing system (9, 11, 12, 13, 15, 16, 17) the mechanism is optimized in a manner to reduce mechanical friction, friction variation and to improve force-direction dependent positioning insensitivity, wherein the circumferential mechanism comprises an outer thread ring (10) with a helical thread (14), and wherein the lens comprises a container element (5) that is filled with a fluid (18), wherein the container element (5) comprises a container ring (5a), wherein the container ring (5a) comprises an outer thread (14a) that meshes with the helical thread (14) so that the container element (5) is moved axially in an axial direction (A) when the thread ring (10) is rotated about the axial direction (A), and wherein the container ring (5a) comprises a first ring (2) and a second ring (3) which both form said outer thread (14a) of the container ring (5a), wherein a spring element (8) is arranged between the first ring (2) and the second ring (3) and is configured to push said rings (2, 3) apart, so as to reduce an axial play of the helical thread (14). ### Claim 2 (depends on 1) The lens of claim 1, wherein the lens comprises an elastic element (8, 21) to preload the ball bearing system. ### Claim 3 (depends on 1) The lens of claim 1, wherein the lens comprises at least one ring-shaped elastic spring element (8, 21) applying a preloading force in a primarily axial direction (A), avoiding axial play within a helical thread, minimizing optical hysteresis in a focal length thereof. ### Claim 4 (depends on 1) The lens of claim 1, wherein the spring element (8, 21) is also applying a preload in a rotational direction to reduce rotational play. ### Claim 5 (depends on 1) The lens of claim 1, wherein the thread ring (10) is supported on a fixed element (1) via a ball bearing (13) comprised by the ball bearing system so that the thread ring (10) is rotatable with respect to the fixed element (1) about the axial direction (A). ### Claim 6 (depends on 1) The lens of claim 1, wherein the lens comprises a transparent and elastically deformable membrane (7), and a transparent cover element (6) facing said membrane (7) in the axial direction (A), wherein the membrane (7), the container ring (5a) and the cover element (6) delimit a volume of the container element (5) that is filled with the fluid, particularly a transparent liquid (18). ### Claim 7 (depends on 6) The lens of claim 6, wherein the container element (5) is guided by a plurality of posts (19a) protruding from the fixed element (1) in the axial direction (A) and extending through through-holes (5b) in the container ring (5a). ### Claim 8 (depends on 6) The lens of claim 6, wherein a lens shaping element (la) that protrudes from the fixed element (1) is configured to press against the membrane (7) depending on the axial position of the container element (5) so that a curvature of the membrane (7) and therewith the focal length of the lens is adjustable by said axial movement of the container element (5). ### Claim 9 (depends on 8) The lens according to claim 8, wherein the spring element (8) is configured to push said rings (2, 3) apart in a way that the axial contact to the thread ring (10) is maintained always on the same side on the helical thread (14). ### Claim 10 (depends on 5) The lens of claim 5, wherein the thread ring (10) is also supported on a housing part (12) that faces the fixed element (1) in the axial direction (A) via a further ball bearing (15) comprised by said ball bearing system, wherein said housing part (12) particularly holds a further transparent cover element (4) facing said cover element (6) of the container element (5) in the axial direction (A), and wherein particularly said housing part (12) is connected to the vertical posts (19a) via an elastic bearing (20). ### Claim 11 A variable focus lens comprising an elastically deformable optical element (7) and a circumferential mechanism (10, 1, 5, 2, 3, 8, 21) to transfer a rotational movement to an axial movement, wherein by using a ball bearing system (9, 11, 12, 13, 15, 16, 17) the mechanism is optimized in a manner to reduce mechanical friction, friction variation and to improve force-direction dependent positioning insensitivity, wherein the lens comprises a container element that is filled with a fluid, wherein the container element (5) comprises a container ring (5a), wherein the container element (5) is guided by a plurality of posts (19a) extending through through-holes (5b) in the container ring (5a). ### Claim 12 A variable focus lens comprising an elastically deformable optical element (7) and a circumferential mechanism (10, 1, 5, 2, 3, 8, 21) to transfer a rotational movement to an axial movement, wherein by using a ball bearing system (9, 11, 12, 13, 15, 16, 17) the mechanism is optimized in a manner to reduce mechanical friction, friction variation and to improve force-direction dependent positioning insensitivity, wherein the circumferential mechanism comprises an outer thread ring (10) with a helical thread (14), which thread ring (10) is supported on a fixed element (1) via a ball bearing (13) comprised by the ball bearing system so that the thread ring (10) is rotatable with respect to the fixed element (1) about an axial direction (A), and wherein the thread ring (10) is also supported on a housing part (12) that faces the fixed element (1) in the axial direction (A) via a further ball bearing (15) comprised by said ball bearing system.