# US 11,906,701 B2 · Anti-reflective surface structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,701 B2 - Document ID: US11906701B2 - Status: Granted - Kind: B2 - Application number: 15/733,255 - Filed: 2018-12-21 - Published: 2021-04-01 - Granted: 2024-02-20 - Earliest claimed: 2017-12-29 - Assignees: 3M Innovative Properties Company - Applicants: 3M Innovative Properties Company - Inventors: Timothy J. Hebrink; Todd G. Pett; Moses M. David; James P. Burke; Vivian W. Jones; Haiyan Zhang - Web page: https://patentgrep.com/patent/US11906701B2 ## CPC - G02B 1/118: having sub-optical wavelength surface structures designed to provide an enhanced transmittance, e.g. moth-eye structures - H10F 19/80: Encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells - B29D 11/0074: {Production of other optical elements not provided for in B29D11/00009- B29D11/0073} - B32B 3/30: characterised by a layer formed with recesses or projections, e.g. {hollows, grooves, protuberances, ribs (apertured layer B32B3/266; layer with cavities or internal voids B32B3/26)} - B32B 37/025: {Transfer laminating} - E04D 13/03: Sky-lights; Domes; Ventilating sky-lights (E04D13/14 takes precedence; structures therefor, {e.g. dormer windows} E04B7/18; {saw-tooth roofs with light-transmission E04B7/12}) - G02B 5/0231: {the surface having microprismatic or micropyramidal shape (macroscopic prism arrays G02B5/045)} - H10F 77/315: {the coatings being antireflective or having enhancing optical properties} - F24S 70/30: Auxiliary coatings, e.g. anti-reflective coatings - F24S 80/52: characterised by the material (for preventing heat loss F24S80/56) - H02S 20/23: specially adapted for roof structures - Y02E 10/50: Photovoltaic [PV] energy - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - E04D: ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS (coverings of outer walls by plaster or other porous material E04F13/00) - F24S: SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS (for producing mechanical power from solar energy F03G6/00) - H02S: GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES (obtaining electrical energy from radioactive sources G21H1/12; light sensitive inorganic semiconductor devices H10F; light sensitive organic semiconductor devices H10K30/00; thermoelectric devices H10N10/00; pyroelectric devices H10N15/00) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Anti-reflective article includes a layer defining an anti-reflective surface. The anti-reflective surface includes a series of alternating micro-peaks and micro-spaces extending along an axis. The surface also includes a series of nano-peaks extending along an axis. The nano-peaks are disposed at least on the micro-spaces and, optionally, the micro-peaks. The article may be disposed on a photovoltaic module or skylight to reduce reflections and resist the collection of dust and dirt. ## Claims ### Claim 1 An article comprising a layer defining an anti-reflective surface extending along an axis, wherein a plane containing the axis defines a cross section of the layer and intersects the surface to define a line describing the surface in two dimensions, the layer comprising: a series of micro-structures at least partially defined by the line, the line defining a series of alternating micro-peaks and micro-spaces along the axis, wherein each micro-space comprises a maximum absolute slope defining an angle from the axis of at most 30 degrees, wherein each micro-peak comprises a first micro-segment defining a first average slope and a second micro-segment defining a second average slope, and wherein an angle formed between the first and second average slopes is at most 120 degrees; and a plurality of nano-structures at least partially defined by the line, the line defining at least one series of nano-peaks disposed on at least the micro-spaces along the axis, wherein each nano-peak has a height and each corresponding micro-peak has a height of at least 10 times the height of the nano-peak, and wherein the micro-spaces have a width of at least 50 micrometers. ### Claim 2 An article comprising a layer defining an anti-reflective surface extending along an axis, wherein a plane containing the axis defines a cross section of the layer and intersects the surface to define a line describing the surface in two dimensions, the layer comprising: a series of micro-structures at least partially defined by the line, the line defining a series of alternating micro-peaks and micro-spaces along the axis, wherein a boundary between each adjacent micro-peak and micro-space includes at least one of a bend or an inflection point of the line; and a plurality of nano-structures at least partially defined by the line, the line defining at least one series of nano-peaks disposed on at least the micro-spaces along the axis, wherein each nano-peak has a height and each corresponding micro-peak has a height at least 10 times the height of the nano-peak, and wherein the micro-spaces have a width of at least 50 micrometers. ### Claim 3 (depends on 1) The article of claim 1, wherein the micro-peak first average slope is positive, and the micro-peak second average slope is negative. ### Claim 4 (depends on 1) The article of claim 1, wherein an absolute value of the micro-peak first average slope is equal to an absolute value of the micro-peak second average slope. ### Claim 5 (depends on 1) The article of claim 1, wherein a width of each micro-space is at least one of: at least 10% of a corresponding micro-peak distance. ### Claim 6 (depends on 1) The article of claim 1, wherein a micro-peak distance between micro-peaks is at least 100 micrometers. ### Claim 7 (depends on 1) The article of claim 1, wherein the micro-peaks have a height of at least 10 micrometers. ### Claim 8 (depends on 1) The article of claim 1, wherein each nano-peak comprises a first nano-segment defining a first average slope and a second nano-segment defining a second average slope, wherein an angle formed between the nano-peak first average slope and the nano-peak second average slope is at most 120 degrees. ### Claim 9 (depends on 8) The article of claim 8, wherein an absolute value of the nano-peak first average slope is different than an absolute value of the nano-peak second average slope. ### Claim 10 (depends on 1) The article of claim 1, wherein the plurality of nano-structures is further disposed on the micro-peaks. ### Claim 11 (depends on 1) The article of claim 1, wherein each nano-peak defines a nano-peak distance and the corresponding micro-peaks define a micro-peak distance of at least 10 times the nano-peak distance. ### Claim 12 (depends on 1) The article of claim 1, wherein a maximum nano-peak distance between nano-peaks is in a range from 1 nanometer to 1 micrometer. ### Claim 13 (depends on 1) The article of claim 1, wherein the layer defining the anti-reflective surface comprises at least one of a fluoropolymer, a polyolefin polymer, or an ultraviolet stable material. ### Claim 14 (depends on 1) The article of claim 1, wherein the nano-peaks comprise at least one masking element. ### Claim 15 (depends on 14) The article of claim 14, wherein the masking element has a diameter of at most 1 micrometer. ### Claim 16 (depends on 1) The article of claim 1, wherein the micro-peaks are non-uniform in at least one of height or shape. ### Claim 17 (depends on 1) The article of claim 1, further comprising an ultraviolet stable adhesive coupled to a side of the layer opposite to the anti-reflective surface, wherein the adhesive is at least one of self-wetting to glass or an air bleed adhesive. ### Claim 18 A method of forming an article comprising a layer defining an anti-reflective surface, the method comprising: forming a series of micro-structures on a surface of a layer, the series of micro-structures comprising a series of alternating micro-peaks and micro-spaces along an axis; disposing a series of nano-sized masking elements on at least the micro-spaces along the axis, wherein the masking elements define a maximum diameter and the corresponding micro-peaks have a height of at least 10 times the maximum diameter of the masking elements; and exposing the surface of the layer to reactive ion etching to form a plurality of nano-structures on the surface of the layer including a series of nano-peaks along the axis, each nano-peak comprising the masking element and a column between the masking element and the layer, wherein the micro-spaces have a width of at least 50 micrometers. ### Claim 19 A method of forming an article comprising a layer defining an anti-reflective surface, the method comprising: extruding a hot melt material comprising an ultraviolet-stable material; shaping the extruded material with a micro-replication tool comprising a mirror image of a series of micro-structures to form the series of micro-structures on the surface of the layer, the series of micro-structures comprising a series of alternating micro-peaks and micro-spaces along an axis; and forming a plurality of nano-structures on the surface of the layer on at least the micro-spaces, the plurality of nano-peaks comprising at least one series of nano-peaks along the axis, wherein the micro-spaces have a width of at least 50 micrometers. ### Claim 20 (depends on 19) The method of claim 19, wherein the plurality of nano-peaks comprises at least one series of nano-peaks along the axis.