# US 2018/0024387 A9 · Waveplate lenses and methods for their fabrication > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0024387 A9 - Document ID: US20180024387A9 - Status: Published application - Kind: A9 - Application number: 14/214,375 - Filed: 2014-03-14 - Published: 2018-01-25 - Earliest claimed: 2010-04-21 - Assignees: Beam Engineering for Advanced Measurements Co.; The United States of America as represented by the Secretary of the Army - Inventors: Nelson Tabirian; Svetlana Serak; Diane Steeves; Brian Kimball - Web page: https://patentgrep.com/patent/US20180024387A9 ## CPC - G02F 1/0136: {for the control of polarisation, e.g. state of polarisation [SOP] control, polarisation scrambling, TE-TM mode conversion or separation (G02F1/0353 takes precedence)} - G02F 1/133365: {Cells in which the active layer comprises a liquid crystalline polymer} - G02F 1/133788: {by light irradiation, e.g. linearly polarised light photo-polymerisation} - G02F 1/134309: {characterised by their geometrical arrangement} - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract The invention provides for lenses fabricated as planar thin film coatings with continuous structure. The lensing action is due to optical axis orientation modulation in the plane of the lens. The lenses of the current invention are fabricated using photoalignment of a liquid crystal polymer wherein the polarization pattern of radiation used for photoalignment is obtained by propagating the light through an optical system comprising a shape-variant nonlinear spatial light polarization modulators. ## Claims ### Claim 1 An optical film comprising a birefringent material, the optical axis orientation angle of said material being a nonlinear function of coordinates in the plane of the film. ### Claim 2 (depends on 1) The optical film as in claim 1 wherein said nonlinear function comprises at least a section of parabolic dependence along a Cartesian coordinate axis in the plane of the film. ### Claim 3 (depends on 1) The optical film as in claim 1 wherein said nonlinear function comprises at least a section of parabolic dependence on the radius of a polar coordinate system in the plane of the film. ### Claim 4 (depends on 1) The optical film as in claim 1 wherein said nonlinear function comprises at least a section of linear dependence of the optical axis orientation angle on the radius of a polar coordinate system in the plane of the film. ### Claim 5 (depends on 1, 2, 3, 4) The optical film as in claims 1-4 wherein said birefringent film is a liquid crystal polymer. ### Claim 6 (depends on 5) The optical film as in claim 5 wherein the optical and mechanical characteristics of said liquid crystal polymer can be controlled by stimuli such as temperature, mechanical stress, and radiation. ### Claim 7 (depends on 1, 2, 3, 4) The optical film as in claims 1-4 wherein said birefringent film is a liquid crystal. ### Claim 8 (depends on 7) The optical film as in claim 7 wherein the optical characteristics of said liquid crystal can be controlled by stimuli such as temperature, radiation, and electric fields. ### Claim 9 (depends on 7) The optical film as in claim 7 further comprising electrodes for application of electric fields across the layer of the film, controlling said orientation pattern. ### Claim 10 A method for fabricating diffractive waveplate optics of nonlinear phase modulation profile comprising: (a) providing a substrate; (b) dispensing a photoaligning material layer over said substrate; (c) providing a light source with wavelength in the absorption band of said photoalignment material; (d) propagating said beam through polarization control optics comprising a polarization converter outputting a spatially nonlinear distribution of linear polarization; (e) further propagating said beam through an optical projection system; (f) exposing said photoaligning material layer to said light beam at the output of said optical projection system. (g) dispensing a polymerizable liquid crystal precursor over the photoaligned material layer; (h) in-situ reacting said polymerizable liquid crystal to form a polymer film. ### Claim 11 (depends on 10) The method for fabricating diffractive waveplate optics as in claim 10 further comprising deposition of the second or more liquid crystal polymer layers, generally, possessing with different material characteristics, including chirality sign. ### Claim 12 (depends on 10) The method as in claim 10 wherein said spatially nonlinear polarization converter comprises an assembly of a first and a second substrates with at least one of them having non-planar surface topology, said substrates treated for inducing alignment of liquid crystalline materials, and a liquid crystalline material being sandwiched in-between. ### Claim 13 (depends on 12) The method as in claim 12 wherein said substrates are plano-convex and plano-concave lenses. ### Claim 14 (depends on 10) The method as in claim 10 wherein said polarization control optics further comprises an input and an output quarter waveplates with their axes aligned parallel or perpendicular to each other. ### Claim 15 (depends on 10) The method as in claim 10 wherein said polarization control optics further comprises an input and an output liquid crystal cells, each possessing a twist, oriented such as the resultant polarization is linear at the absence of the nonlinear polarization converter. ### Claim 16 (depends on 10) The method as in claim 10 wherein said nonlinear polarization converter comprises a diffractive waveplate-lens meeting half-wave phase retardation condition for the wavelength of the recording radiation. ### Claim 17 (depends on 10) The method as in claim 10 wherein said nonlinear polarization converter comprises material with spatially varying optical anisotropy. ### Claim 18 An imaging system comprising at least one waveplate-lens film. ### Claim 19 (depends on 18) The system as in claim 18 further comprising at least one variable phase retardation plate. ### Claim 20 An optical film made of a liquid crystalline material between substrates inducing different orientation states, including a combination of planar alignment and a spatially nonlinear alignment pattern.