# US 11,079,590 B2 · Modulating retroreflective piezoelectric multilayer film > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,590 B2 - Document ID: US11079590B2 - Status: Granted - Kind: B2 - Application number: 16/327,932 - Filed: 2017-08-25 - Published: 2019-06-20 - Granted: 2021-08-03 - Earliest claimed: 2016-08-26 - Assignees: Andrew Simon FILO - Applicants: Andrew Simon Filo - Inventors: Andrew Simon Filo - Web page: https://patentgrep.com/patent/US11079590B2 ## CPC - G02B 26/02: for controlling the intensity of light {(G02B26/004 takes precedence)} - G01S 17/74: Systems using reradiation of electromagnetic waves other than radio waves, e.g. IFF, i.e. identification of friend or foe - G02B 5/124: plural reflecting elements forming part of a unitary plate or sheet - G09F 3/02: Forms or constructions (layered products B32B) - G09F 3/10: by an adhesive layer - H10F 77/90: Energy storage means directly associated or integrated with photovoltaic cells, e.g. capacitors integrated with photovoltaic cells - H10N 30/204: {using bending displacement, e.g. unimorph, bimorph or multimorph cantilever or membrane benders} - H10N 30/857: Macromolecular compositions - H10N 30/878: {the principal material being non-metallic, e.g. oxide or carbon based} - H10N 39/00: Integrated devices, or assemblies of multiple devices, comprising at least one piezoelectric, electrostrictive or magnetostrictive element covered by groups H10N30/00 – H10N35/00 - B64G 1/1085: {Swarms and constellations} - B64G 1/66: Arrangements or adaptations of apparatus or instruments, not otherwise provided for - G09F 2003/0257: {Multilayer} - Y02E 10/50: Photovoltaic [PV] energy - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - B64G: COSMONAUTICS; VEHICLES OR EQUIPMENT THEREFOR - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Provided herein is a modulating retroreflective multilayer film comprising retroreflective elements, a piezoelectric layer, a photovoltaic layer, and an energy storage device. The stacked and transparent layered configuration of the film allows the retroreflective elements and the photovoltaic layer to be simultaneously illuminated by a narrow beam. The low power piezoelectric layer and the energy harvesting of the photovoltaic layer allow the retroreflector to be energetically self-sufficient and suitable for remote deployment. The flexible properties of the component layers allow the retroreflector to be adhered to nonplanar or irregular surfaces for the purpose of labeling and tagging. ## Claims ### Claim 1 A modulating retroreflective multilayer film comprising: retroreflective elements; a piezoelectric layer having opposing top and bottom surfaces; a first electrode layer in electrical connection with the top surface of the piezoelectric layer; a second electrode layer in electrical connection with the bottom surface of the piezoelectric layer; a voltage source located within a layer of the multilayer film and being in electrical connection with the first and second electrode layers; a processor located within a layer of the multilayer film and being communicably coupled with the voltage source to apply a voltage across the piezoelectric layer; an energy storage device located within a layer of the multilayer film and being configured to store energy used for the applying of the voltage; and a photovoltaic layer communicably in electrical connection with the energy storage device and coupled with the processor to transmit electrical signals to the processor; wherein the piezoelectric layer and the photovoltaic layer are substantially coextensive with one another. ### Claim 2 (depends on 1) The multilayer film of claim 1, wherein the retroreflective elements are disposed on the top surface or the bottom surface of the piezoelectric layer. ### Claim 3 (depends on 1) The multilayer film of claim 1, further comprising: a retroreflective layer comprising at least some of the retroreflective elements. ### Claim 4 (depends on 1) The multilayer film of claim 1, wherein at least a portion of each of the piezoelectric layer, the first electrode layer, and the second electrode layer is transparent. ### Claim 5 (depends on 1) The multilayer film of claim 1, wherein the energy storage device is in communication with the processor to provide power to the processor. ### Claim 6 (depends on 1) The multilayer film of claim 1, wherein the photovoltaic layer is configured to harvest energy to be stored in the energy storage device. ### Claim 7 (depends on 1) The multilayer film of claim 1, wherein the energy storage device comprises a battery or a capacitor. ### Claim 8 (depends on 1) The multilayer film of claim 1, wherein the retroreflective elements comprise microprism retroreflectors or holographic retroreflectors. ### Claim 9 (depends on 1) The multilayer film of claim 1, wherein the retroreflective elements are disposed on a retroreflective surface at a density of greater than 10 per square millimeter. ### Claim 10 (depends on 1) The multilayer film of claim 1, wherein the piezoelectric layer comprises polyvinylidene fluoride. ### Claim 11 (depends on 1) The multilayer film of claim 1, having a durometer hardness of less than 50. ### Claim 12 (depends on 1) The multilayer film of claim 1, having a thickness of less than 100 microns. ### Claim 13 A label comprising: a modulating retroreflective multilayer film comprising: retroreflective elements; a piezoelectric layer having opposing top and bottom surfaces; a first electrode layer in electrical connection with the top surface of the piezoelectric layer; a second electrode layer in electrical connection with the bottom surface of the piezoelectric layer; a voltage source located within a layer of the multilayer film and being in electrical connection with the first and second electrode layers; a processor located within a layer of the multilayer film and being communicably coupled with the voltage source to apply a voltage across the piezoelectric layer; an energy storage device located within a layer of the multilayer film and being configured to store energy used for the applying of the voltage; and a photovoltaic layer communicably in electrical connection with the energy storage device and coupled with the processor to transmit electrical signals to the processor; and one or more adhesive layers, wherein one of the one or more adhesive layers is an outer adhesive layer located at an end of the multilayer film. ### Claim 14 (depends on 13) The label of claim 13, further comprising: a release liner disposed on the outer adhesive layer. ### Claim 15 A method for modulating retroreflected light, the method comprising: providing a modulating retroreflective multilayer film comprising: retroreflective elements; a piezoelectric layer having opposing top and bottom surfaces; a first electrode layer in electrical connection with the top surface of the piezoelectric layer; a second electrode layer in electrical connection with the bottom surface of the piezoelectric layer; a voltage source located within a layer of the multilayer film and being in electrical connection with the first and second electrode layers; a processor located within a layer of the multilayer film and being communicably coupled with the voltage source to apply a voltage across the piezoelectric layer; an energy storage device located within a layer of the multilayer film and being configured to store energy used for the applying of the voltage; and a photovoltaic layer communicably in electrical connection with the energy storage device and coupled with the processor to transmit electrical signals to the processor illuminating the film with an incident light beam; retroreflecting the incident light beam into a reflected light beam via a first configuration of retroreflective elements; detecting the incident light beam with the photovoltaic layer; transmitting a signal from the photovoltaic layer to the processor; applying a voltage across the piezoelectric layer to change a dimension of the piezoelectric layer to form a second configuration of retroreflective elements; and retroreflecting the incident light beam into a modulated light beam via the second configuration of retroreflective elements. ### Claim 16 (depends on 15) The method of claim 15, further comprising: harvesting energy to be stored in the energy storage device with the photovoltaic layer. ### Claim 17 (depends on 15) The method of claim 15, wherein the voltage is applied with a power of less than 1 nanowatt.