# US 12,768,505 B2 · LED filament > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,768,505 B2 - Document ID: US12768505B2 - Status: Granted - Kind: B2 - Application number: 18/840,968 - Filed: 2023-02-16 - Published: 2025-06-12 - Granted: 2026-10-20 - Earliest claimed: 2022-02-24 - Assignees: Signify Holding B.V. - Applicants: Signify Holding B.V. - Inventors: Ties Van Bommel; Robert Jacob Pet - Web page: https://patentgrep.com/patent/US12768505B2 ## CPC - F21K 9/232: specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb - F21Y 2107/30: on the outer surface of cylindrical surfaces, e.g. rod-shaped supports having a circular or a polygonal cross section - F21Y 2115/10: Light-emitting diodes [LED] - F21K: NON-ELECTRIC LIGHT SOURCES USING LUMINESCENCE; LIGHT SOURCES USING ELECTROCHEMILUMINESCENCE; LIGHT SOURCES USING CHARGES OF COMBUSTIBLE MATERIAL; LIGHT SOURCES USING SEMICONDUCTOR DEVICES AS LIGHT-GENERATING ELEMENTS; LIGHT SOURCES NOT OTHERWISE PROVIDED FOR - F21Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED ## Abstract The present invention relates to an LED filament (10) for providing LED filament light (12), comprising: an elongated carrier (14); and a plurality of light emitting diodes (16) arranged on the elongated carrier, wherein the LED filament is arranged in a coiled-coil configuration. ## Claims ### Claim 1 An LED filament for providing LED filament light, comprising: an elongated carrier having a first major surface and an opposite second major surface; a plurality of light emitting diodes arranged on the first major surface of the elongated carrier; and a ductile element arranged on the second major surface of the elongated carrier and along at least a major portion of a length of the elongated carrier, the ductile element being configured to allow the LED filament to be shaped from a basic shape into a first coiled shape corresponding to the primary coil and a second coiled shape corresponding to the secondary coil, the first coiled shape and the second coiled shape being dimensionally stable, wherein the LED filament is arranged in a coiled-coil configuration, the coiled-coil configuration comprises a primary coil having a primary diameter D1, which primary coil is coiled into a secondary coil having a secondary diameter D2, and wherein the plurality of light emitting diodes comprises blue and/or UV light emitting diodes, the plurality of light emitting diodes are covered by an elongated encapsulant, and the elongated encapsulant comprises luminescent material configured to at least partly convert LED light emitted by the blue and/or UV light emitting diodes into converted light. ### Claim 2 (depends on 1) The LED filament according to claim 1, wherein the primary diameter D1 is in the range from 4 mm to 12 mm. ### Claim 3 (depends on 1) The LED filament according to claim 1, wherein the secondary diameter D2 is in the range from 4·D1 to 12·D1. ### Claim 4 (depends on 1) The LED filament according to claim 1, wherein the primary coil comprises N1 primary loops and the secondary coil comprises N2 secondary loops, and wherein N1≥5·N2. ### Claim 5 (depends on 1) The LED filament according to claim 1, wherein the secondary coil has a secondary pitch P2 in the range from 2·D1 to 10·D1. ### Claim 6 (depends on 1) The LED filament according to claim 1, wherein the plurality of light emitting diodes comprises a first set of first light emitting diodes and a second set of second light emitting diodes, wherein the first set is individually controllable in relation to the second set. ### Claim 7 (depends on 1) The LED filament according to claim 1, wherein the primary coil is formed around and mounted to a rod, and wherein the rod has one or more of the following properties: (i) reflective to reflect at least part of the LED filament light; (ii) light diffusive to diffuse at least part of the LED filament light; (iii) light converting to convert at least part of the LED filament light; (iv) transmissive to act as a lightguide guiding at least part of the LED filament light; and (v) thermally conductive to act as a heatsink. ### Claim 8 (depends on 1) The LED filament according to claim 1, wherein the LED filament is arranged in a triple coiled coil configuration. ### Claim 9 (depends on 1) A lamp or a luminaire comprising at least one coiled-coil LED filament according to claim 1 arranged behind a light exit window. ### Claim 10 (depends on 9) A lamp or a luminaire according to claim 9, wherein the at least one coiled-coil LED filament is a plurality of coiled-coil LED filaments. ### Claim 11 (depends on 10) A lamp or a luminaire according to claim 10, wherein the plurality of coiled-coil LED filaments comprises at least two coiled-coil LED filaments entangled. ### Claim 12 (depends on 1) The LED filament according to claim 1, wherein the ductile element comprises a metal wire or a metal strip. ### Claim 13 (depends on 1) The LED filament according to claim 1, wherein the elongated carrier is coiled into the primary coil such that the first major surface with the plurality of light emitting diodes is arranged on an outside of the primary coil. ### Claim 14 (depends on 1) The LED filament according to claim 1, wherein at least a shape of the primary coil is fixed by a glue or a thermoplastic polymer. ### Claim 15 (depends on 1) The LED filament according to claim 1, wherein the secondary diameter D2 varies over a length of the LED filament such that D2 is smaller at ends of the LED filament than at a longitudinal center of the LED filament. ### Claim 16 A method of manufacturing an LED filament, comprising: providing a flexible carrier having a first major surface and an opposite second major surface, a ductile element being arranged on the second major surface of the flexible carrier and along at least a major portion of a length of the flexible carrier, a plurality of light emitting diodes being arranged on the first major surface of the flexible carrier, the plurality of light emitting diodes having blue and/or UV light emitting diodes, the plurality of light emitting diodes being covered by an elongated encapsulant, and the elongated encapsulant having luminescent material configured to at least partly convert LED light emitted by the blue and/or UV light emitting diodes into converted light; coiling the provided flexible carrier around a rod to provide an LED filament having a primary coil with a primary diameter D1, the ductile element shaping the LED filament into a first coiled shape corresponding to the primary coil that is dimensionally stable; and coiling the LED filament having the primary coil into a secondary coil having a secondary diameter D2 to provide an LED filament having a coiled-coil configuration, the ductile element shaping the LED filament into a second coiled shape corresponding to the secondary coil that is dimensionally stable.