LED filament configuration

Abstract

A light emitting diode (LED) filament configuration 100 includes at least one LED filament 110 comprising an array of light emitting diodes (LEDs). The at least one LED filament 110 is elongated in shape and extends at least partially along an axis A. The at least one LED filament includes at least one branch 120, 121 extending from the elongated LED filament 110 and disposed at an angle α relative to the axis A.

Description

Technical Field

[0001] The present invention generally relates to lighting configurations comprising one or more light emitting diodes (LEDs).

Background Art

[0002] The use of light emitting diodes (LEDs) for lighting purposes has continued to attract attention. Compared to incandescent lamps, fluorescent lamps, neon tube lamps, etc., LEDs offer numerous advantages such as longer operating life, reduced power consumption, and improved efficiency regarding the ratio of light energy to heat energy.

[0003] In particular, lighting devices and / or lighting configurations (such as lamps) comprising LEDs currently receive extremely high interest, and incandescent lamps are being rapidly replaced by LED-based lighting solutions. Nevertheless, having a retrofit lighting device (e.g., a lamp) with the appearance of an incandescent bulb is evaluated and desired. In particular, lamps utilizing an LED filament arranged within a bulb similar to that of an incandescent lamp are highly evaluated because they are decorative like incandescent lamps while still retaining the advantages of LEDs.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, it is desired to provide alternatives for the configuration and arrangement of LED lamps, especially regarding the design of LED filaments. More specifically, there is a need to improve the efficiency, dynamics, and decorative effects of prior art LED filament lamps.

[0005] Therefore, it is an object of the present invention to provide an alternative to prior art LED filament configurations in order to improve the dynamics, efficiency, and decorative aspects of LED filament lamps.

[0006] International Publication No. 2019 / 015763 discloses an LED lamp comprising a transparent housing having a spherical shape, a flexible LED filament mounted inside the transparent housing in a curved shape, and a filament holder mounted on a base portion and extending into the transparent housing, the filament holder having a plurality of holding portions arranged to hold the flexible LED filament at a plurality of spaced positions along its length, thereby defining the curved shape of the flexible LED filament.

Means for Solving the Problems

[0007] It is an object to provide an alternative LED filament in order to improve the dynamic, efficiency, and decorative aspects during operation.

[0008] The LED filament supplies LED filament light and includes a plurality of light-emitting diodes (LEDs) arranged in a linear array. Preferably, the LED filament has a length L and a width W, and L > 5W. The LED filament may be arranged in a linear configuration or in a non-linear configuration such as, for example, a curved configuration, a 2D / 3D spiral, or a helix. Preferably, the LEDs are arranged on an elongated support such as a substrate, which may be rigid (e.g., made of a polymer, glass, quartz, metal, or sapphire) or flexible (e.g., made of a polymer or metal, such as a film or foil).

[0009] When the support includes a first major surface and an opposite second major surface, the LEDs are arranged on at least one of these surfaces. The support may be reflective or may be light-transmissive such as translucent and preferably transparent.

[0010] The LED filament may comprise an encapsulant that at least partially covers at least some of the plurality of LEDs. The encapsulant may also at least partially cover at least one of the first major surface or the second major surface. The encapsulant may be a polymeric material that can be flexible, such as silicone for example. Further, the LEDs may be configured to emit LED light of various colors or spectra for example. The encapsulant may include a luminescent material configured to at least partially convert the LED light into converted light. The luminescent material may be a phosphor, such as an inorganic phosphor and / or a quantum dot or a quantum rod.

[0011] The LED filament may include a plurality of sub-filaments.

[0012] This and other objects are achieved by providing an LED filament configuration and an LED filament device having the features in the independent claims. Preferred embodiments are defined in the dependent claims.

[0013] Accordingly, according to a first aspect of the present invention, there is provided a light emitting diode (LED) filament configuration. The LED filament configuration comprises at least one LED filament comprising an array of a plurality of light emitting diodes (LEDs). The at least one LED filament has an elongated shape that at least partially extends along an axis A. The LED filament configuration further comprises a branch, and at least one LED filament (110) branches into at least two branches from the branch, and at least one branch of the LED filament among the at least two branches is arranged at an angle with respect to the axis A so as to extend from the elongated body.

[0014] Here, the term branch is used in the sense of fork, bifurcation, or any other term to clarify that the LED filament branches into two or more directions similar to the branches of a tree.

[0015] In a further embodiment of the present invention, at least one LED filament comprises an encapsulant that integrally surrounds the LED filament, including at least two branches. This has the advantage that the different branches form a completely encapsulated portion that covers the transition from one part of the LED filament configuration to another. In other words, the one-piece encapsulant covers the LED filament, including the branching region.

[0016] In another embodiment, the LEDs in the array are arranged to provide a continuous light distribution across the entire LED filament, including at least two branches. This has a satisfactory effect in that in the illumination pattern of the LED filament, the branching region exhibits the same intensity and is not a dark part of the filament.

[0017] For having simple wiring, in a further embodiment, in the LED filament configuration, the emission lines of the array of a plurality of LEDs continue to the branches. This has the advantage that the LEDs in the filament are, for example, all connected in series and only two wires are present that are necessary to drive all the branches of the LED filament configuration. In other configurations, the LEDs of different branches may be connected in parallel such that each branch has a separate electrical connection.

[0018] According to a second aspect of the present invention, there is provided an LED filament device comprising n sets of LED filaments. In the LED filament device, each set of LED filaments comprises at least one LED filament comprising an array of a plurality of light emitting diodes (LEDs). At least one of the LED filaments is in an elongated shape that at least partially extends along an axis A. The at least one LED filament comprises at least one branch portion arranged at an angle α with respect to the axis A. At least one LED filament of the (k + 1)-th set of LED filaments repeatedly constitutes at least one branch portion of at least one LED filament of the k-th set of LED filaments for k = 1, 2,..., n - 1, whereby the n sets of LED filaments are configured such that the LED filaments of the LED filament device constitute a tree-like structure of the LED filaments.

[0019] Thus, the first and second aspects of the present invention share a common overall inventive concept or idea in that they provide an LED filament configuration or device in which the LED filaments are configured to form a specific structure. According to the first and second aspects of the present invention, the LED filaments have an elongated shape extending along the axis A, and at least one branch portion extends from the axis A. The branched LED filaments will have more than two ends and may be accompanied by, for example, bifurcated or trifurcated LED filaments. This means that the present invention can have a more complex LED filament structure than previously known. Illumination with such an LED filament configuration can be more dynamic and efficient than other non-branched LED filaments.

[0020] It will be appreciated that the LED filament configuration can disperse the light emitted by the LEDs in a specific pattern depending on the configuration of the LED filaments. Thereby, the present invention is advantageous in that the LED filament configuration or device can guide or disperse light in order to achieve high efficiency with respect to light distribution as compared to an LED filament unit not comprising branched filaments.

[0021] The present invention is further advantageous in that the branched LED filaments of the LED filament configuration / device can be conveniently designed to provide a desired lighting distribution from the viewpoint of lighting purposes and / or decorative purposes. For example, characteristics such as the shape and size of the branches of the LED filament may be selected for different lighting purposes of the LED configuration / device.

[0022] The present invention is further advantageous in that the LEDs of the LED filament configuration can emit light from the LED filament and its branches in a continuous line or plane, thereby achieving a further improved decorative light effect and / or a better imitation of the filaments of conventional lamps / light bulbs.

[0023] As can be understood from the second aspect of the present invention, the LED filament device may comprise a combined branched LED filament that can form a relatively complex pattern such as a tree-like structure. This can further improve the lighting efficiency, dynamics and / or decorative aspects of the lighting configuration.

[0024] For example, the branched LED filament configuration according to the present invention may be configured such that a specific pattern or visual effect is achieved. Specifically, the light may spread more uniformly or may be intentionally emphasized in a specific region of the LED filament configuration.

[0025] It will be understood that the LED filament configuration / device of the present invention further comprises a relatively small number of components. The relatively small number of components is advantageous in that the LED filament configuration or device can be manufactured at a relatively low cost.

[0026] The LED filament configuration and the LED filament device according to the first and second aspects of the present invention each comprise at least one LED filament. The at least one LED filament similarly includes an array of LEDs. The term "array" here means, for example, a linear configuration or chain of LEDs arranged on the LED filament. The LED filament configuration according to the first aspect of the present invention comprises at least one branch of the LED filament. The term "branch" here means a structure, unit, etc. that is structurally part of the LED filament. In other words, the LED filament may comprise a first (main) part and a second part arranged at an angle to the first part, with the second part constituting the branch. The branch may in its physical entity comprise the same or similar components as the LED filament. This means that both the branch of the LED filament and the elongated body along axis A may comprise LEDs and a support substrate to which the diodes are attached, etc. It will be understood that the branch of the LED filament may have different characteristics from other parts / branches of the LED filament. Further, the branch of the LED filament is arranged at an angle α to axis A so as to form a branched shape of the LED filament.

[0027] According to an embodiment of the present invention, the at least one LED filament comprises a plurality of branches. For example, the LED filament may comprise N branches, where N is preferably between 2 and 4. Therefore, the LED filament may comprise branches extending from one or more sides of the elongated shape. Further, the branches may have various sizes and / or the branches may be arranged at the same or different angles to axis A. This embodiment is advantageous in that a better imitation of the conventional filament of a lamp / light bulb can be achieved.

[0028] This is advantageous because it means that the plurality of branches create opportunities for more complex LED filaments and LED filament configurations. This type of more complex structure can improve the aesthetics of the LED filament configuration and can not only become highly decorative, but can also improve lighting efficiency as well as light scattering and distribution. Thus, since the LED lamp is more resource and energy efficient, for example, the desirable areas of use where it can further replace incandescent lamps can expand. The possibility of obtaining a relatively complex structure using a small number of components is advantageous in that the LED filament configuration can be manufactured relatively inexpensively.

[0029] According to one embodiment of the present invention, at least a first branch among the plurality of branches of the LED filament has a length different from that of a second branch among the plurality of branches of the LED filament. Therefore, at least one branch among the plurality of branches of the LED filament has a length different from that of the other branches. This embodiment is advantageous for further enhancing alternative configurations of the branches and the LED filament, and thus also the versatility of the LED filament configuration. This embodiment can further result in an arrangement of the LED filament in a manner that may be inappropriate or impossible in the case of branches of equal length. Furthermore, it is understood that the lighting dynamics of the branched LED filament having branches of various lengths are enhanced.

[0030] According to one embodiment of the present invention, at least one LED filament is Y-shaped. In other words, the LED filament is bifurcated such that there is one lower end of the LED filament and two ends at the upper part on the opposite side of the LED filament. This embodiment is advantageous in that the Y-shape further improves the light distribution of the LED filament. The Y-shaped LED filament can have the advantage of being particularly suitable for combinations within the LED filament device as described above. For example, a tree-like structure of the LED filament configuration is conveniently achieved, thus enhancing the characteristics of such an LED filament configuration together with ease of manufacture. Furthermore, the Y-shaped LED filament can be advantageous in that a symmetric arrangement of the LED filament configuration can be realized, resulting in a more uniform light distribution.

[0031] According to an embodiment of the present invention, at least one LED filament is in an X shape. In other words, the branched LED filament of the LED filament configuration is configured to have four ends such that two ends are arranged at the upper part and two ends are arranged at the lower part. This embodiment is advantageous in that the X-shaped LED filament is substantially symmetric. This can result in more omnidirectional light scattering, increase efficiency, and improve light distribution. Furthermore, the X-shaped LED filament can achieve a complex structure with multiple intersections within the LED configuration, and thus can demonstrate advantages for further enhancing the lighting effect and light distribution.

[0032] According to an embodiment of the present invention, at least a set of LEDs among the plurality of LEDs within the LED filament are connected in series. This embodiment is advantageous because a specific lighting effect can be achieved in which equal light intensity is conveniently achieved across the plurality of diodes within the set. Furthermore, the embodiment is advantageous because a set of diodes connected in series can constitute a specific part such as a branch of the LED filament. This can further improve the possibility of creating a specific light scattering configuration, for example, enhancing the dynamics. Furthermore, this can improve the simplicity of manufacturing, thereby reducing the economic cost.

[0033] According to one embodiment of the present invention, at least a first set of LEDs and at least a second set of LEDs among the plurality of LEDs in the LED filament are connected in parallel. This means that while some of the plurality of LEDs are arranged in parallel connection, others can be in series connection. One embodiment can be seen in that the LEDs in a particular branch of the LED filament are arranged in parallel, while other LEDs in the LED filament can be configured in a different manner. This embodiment is advantageous because lighting configurations with different characteristics within the LED filament can be achieved in a cost - effective and easily manufacturable manner. Furthermore, the parallel connection of the LEDs can demonstrate a more sustainable embodiment due to increased durability.

[0034] According to one embodiment of the present invention, at least a first set of LEDs and at least a second set of LEDs among the plurality of LEDs are configured to emit light having at least one of the same color temperature and the same luminous intensity. This means that the color temperature, the luminous intensity, or both the color temperature and the luminous intensity can be the same for the plurality of LEDs within the LED filament configuration. This embodiment is advantageous in that the LED filament configuration provides an efficient solution for uniform light distribution.

[0035] A "set" of LEDs here means a plurality of LEDs adjacent to each other and interconnected by wiring. For example, the LEDs in one branch of the LED filament can form a set of LEDs, while the LEDs in a second branch can form a different set of LEDs.

[0036] According to an embodiment of the present invention, at least a first set of LEDs among the plurality of LEDs and at least a second set of LEDs among the plurality of LEDs are configured to emit light having at least one of different color temperatures and different luminous intensities. It will be understood that LED filaments of different color temperatures or luminous intensities can often result in a desirable aesthetically pleasing effect. This embodiment is further beneficial because one LED filament can include branches having different color temperatures, meaning that there is no need for multiple filaments to achieve the desired decorative effect. This is beneficial because embodiments of the LED filament configuration can thus be smaller, more energy efficient, and less expensive to manufacture.

[0037] According to one embodiment of the present invention, the LED filament may further include an encapsulant that at least partially surrounds a plurality of LEDs. The encapsulant may include a luminescent material and may be configured to at least partially convert the light emitted by the plurality of LEDs. Therefore, the encapsulant is configured to at least partially convert the light emitted by the plurality of LEDs into converted light. The term "encapsulant" here means a material, element, structure, etc. configured or arranged to surround, enclose, and / or encapsulate a plurality of LEDs of the LED filament. The luminescent material of the encapsulant is configured to emit light under external energy excitation. For example, the luminescent material may include a fluorescent material. The luminescent material may include an inorganic phosphor, an organic phosphor, and / or quantum dots / quantum rods. The encapsulant is configured to at least partially convert the light emitted by the plurality of LEDs into converted light. For example, UV / blue LED light may be partially or completely absorbed by the luminescent material and converted into light of another color, such as green, yellow, orange, and / or red. Preferably, the encapsulant of the LED filament is used with blue and / or UV LEDs. Further, for example, when the LED filament includes RGB LEDs, the encapsulant may include a light-scattering material for scattering the light of the (RGB) LEDs. The light-scattering material may include a light-scattering material such as BaSO4 particles, Al2O3 particles, and / or TiO2 particles.

[0038] For example, the encapsulant, including the luminescent material and / or the light-scattering material, may be arranged in a continuous profile on the LED filament and its branches, thereby obtaining an improved decorative lighting effect and / or a better imitation of the filament of a conventional lamp / light bulb.

[0039] According to an embodiment of the present invention, the angle α between at least one branch of the LED filament and the axis A is (preferably) in the range of 10 to 80 degrees, for example, (more preferably) 20 to 60 degrees, (most preferably) 30 to 50 degrees, etc. This embodiment is advantageous in that the exemplified angle between the branch and the axis A of the LED filament is preferable at least from an aesthetic point of view.

[0040] According to an embodiment of the present invention, each branch of at least one branch is arranged at an angle α of at least 90 degrees with respect to the axis A.

[0041] According to an embodiment of the present invention, an LED filament unit including a plurality of LED filament configurations is provided. According to one of the above-described embodiments, the plurality of LED filament configurations are combined such that at least a first LED filament among the plurality of LED filament configurations is physically in contact with at least a second LED filament among the plurality of LED filament configurations. In other words, one or more first LED filaments are connected to one or more second LED filaments, for example, via one or more electrical contacts. This is advantageous because a specific light scattering effect can be achieved and the LED filament unit can expand the intended use area. In addition, the physical contact between the LED filaments may also include electrical contact between the LED filaments. Therefore, the LED filament configurations in the LED filament unit may be combined to form a structure in which each individual LED filament configuration does not need to be attached to an electrode other than that of another LED filament. This is advantageous because it can provide an LED filament unit that is easier and requires fewer resources.

[0042] According to one embodiment of the present invention, the LED filament device includes at least a first branch portion having a length different from that of at least a second branch portion of the LED filament device. According to an alternative embodiment of the present invention, the LED filament device includes at least a first branch portion having the same length as at least a second branch portion of the LED filament device.

[0043] The described variations of the LED filament device are useful for creating further aesthetically pleasing structures where the length relationship of the branches is selected to best suit a particular lighting purpose, resulting in different structures and lighting effects. This is advantageous as the LED filament device can be easily manufactured for a plurality of various requirements with relatively few modifications, thus reducing manufacturing costs. Additionally, the LED filament device may have the advantage of being more durable than other complex structures used to replace incandescent lamps.

Brief Description of the Drawings

[0044] The above and additional objects, features, and advantages of the present invention will be better understood from the following illustrative and non - limiting detailed description of embodiments of the present invention with reference to the accompanying drawings. Refer to the accompanying drawings.

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[0045] All the figures are schematic and generally not to scale, showing only the parts necessary to illustrate the present invention in general, and other parts may be omitted or merely suggested.

Mode for Carrying Out the Invention

[0046] FIG. 1 shows a schematic diagram of an LED filament configuration 100 according to an exemplary embodiment of the present invention. The LED filament configuration 100 includes an elongated LED filament 110 along axis A. Further, the LED filament 110 also includes two branches 120, 121 extending from the elongated LED filament 110 at the branch. Note that the number of branches of the LED filament 110 is arbitrary, and the two branches 120, 121 are shown as an example.

[0047] The branch 120 of the LED filament 110 extends at an angle α from axis A. The angle α may preferably be in the range of 10 to 80 degrees, preferably 20 to 60 degrees, and most preferably 30 to 50 degrees. The LED filament 110 of the present embodiment includes two branches 120, 121 extending at the same angle from axis α. However, the branches 120, 121 of the LED filament 110 may have different angles α, and thus an asymmetric shape may be obtained.

[0048] The LED filament configuration 100 includes a plurality of LEDs (not shown) that can be attached to a support. The support may be a substrate that can be flexible or rigid.

[0049] The LED filament 110 further includes an encapsulant containing a translucent material, and the encapsulant at least partially surrounds a plurality of LEDs. For example, the encapsulant may completely surround the plurality of LEDs, that is, including the branched portions. The encapsulant is preferably a polymer material, for example, made of silicon.

[0050] The LED may be a direct-emitting LED that provides color. The LED may be an RGB, UV, or blue LED. Further combinations of LEDs, for example, a UV LED and a blue light LED, may be used. The LED may also include a laser diode.

[0051] The color temperature of the white light is preferably in the range of 1800 - 6000K, more preferably in the range of 2000 - 5000K, and most preferably in the range of 2200 - 4000K, such as 2300K or 2700K for example. The white light preferably has a CRI of at least 75, more preferably at least 80, and most preferably at least 85, such as 90 or 92 for example.

[0052] The encapsulant of the LED filament 110 may include a luminescent material configured to emit light under external energy excitation. The UV / blue LED light may be partially or completely absorbed by the luminescent material and converted into light of another color, such as green, yellow, orange, and / or red. The luminescent material may include, for example, inorganic phosphors, organic phosphors, and / or quantum dots / rods.

[0053] Figures 2a and 2b show further embodiments of the LED filament configuration 100. Note that the LED filament configuration 100 of Figures 2a and 2b may be configured in the same manner as the LED filament configuration 100 described in relation to Figure 1. Figure 1 is referred to for better understanding. Figure 2a shows a Y-shaped LED filament configuration 100, and Figure 2b shows an X-shaped LED filament configuration 100 (although not shown, the LED filament configuration 100 may alternatively have a K shape). The LED filaments 110 shown in Figures 2a and 2b represent embodiments provided with a plurality of branches. As can be seen, the LED filament 110 may comprise different numbers of branches 120, 121. The branches 120, 121 of the LED filament 110 may be directed, for example, at different angles and in different directions, and may be of different lengths.

[0054] As illustrated in Figure 2a, the Y-shaped LED filament 110 may comprise branches 120, 121 of equal or unequal length while still maintaining the Y shape.

[0055] As shown in Figure 2b, a symmetric X-shaped LED filament 110 is provided such that a plurality of ends are obtained at both the upper and lower portions of the LED filament 110. The X-shaped LED filament 110 comprises four branches 120, 121, 122, 123 having a branch at the center of the X-shaped LED filament. The X-shaped LED filament 110 can also be asymmetric in the same manner as the Y-shaped LED filament 110 discussed with respect to Figure 2a.

[0056] Figures 3a and 3b schematically show a cross-section of the LED filament 110 of the LED filament configuration 100 comprising an array or "chain" of LEDs 130. The LEDs are arranged within the LED filament configuration 100 such that the emission lines of an array of a plurality of LEDs continue to the branches.

[0057] The array of LED130s may comprise a plurality of LED130s arranged adjacent to each other, and wiring may be provided between each pair of LED130s.

[0058] FIG. 3a shows one embodiment in which all the LED130s are connected in series.

[0059] FIG. 3b shows one embodiment of an LED filament configuration 100 comprising two branches 120, 121. A plurality of LEDs in the array of LED130s may be further defined as sets of LEDs 131, 132, 133. Here, the LED filament 110 comprises individual sets of LEDs 131, 132 in which the sets of LEDs 131, 132 are connected in parallel. The set of LEDs 133 in the non-branching portion of the LED filament 110 is connected in series with the sets of LEDs 131, 132 of the branches.

[0060] Other embodiments may look at further combinations of sets or individual LEDs connected in parallel, in series, or any combination thereof. The structure of the LED filament may, for example, make different portions of the LED filament configuration 100 have different luminous intensities.

[0061] FIG. 4 shows one embodiment of an LED filament configuration 100 in which a portion 105 of the LED filament 110 has a different color temperature or a different luminous intensity from the branches 120, 121 of the LED filament 110. It is understood that other portions or combinations of portions of the LED filament 110 may be configured to have different color temperatures or luminous intensities. For example, different colors (temperatures) may be obtained by using LEDs that emit different colors in different portions of the LED filament configuration 100, for example, within the encapsulant of the LED filament 110, and / or by using different luminescent materials (such as phosphors, for example, a red phosphor or a combination of yellow and red phosphors).

[0062] FIG. 5 shows a schematic diagram of an embodiment of the LED filament unit 140. As shown, the LED filament unit 140 may include two LED filament configurations 100, 101 that are physically and electrically connected. In this exemplary illustration, the two end portions of the LED filaments 100, 101 are in contact, but other configurations are possible. Further, the LED filament unit 140 may include any plurality of LED filament configurations 100, 101. Further, the LED filaments 100, 101 may be arranged in any desired manner such that at least one LED filament configuration 100 is physically in contact with at least one other LED filament configuration 101.

[0063] FIGS. 6a, 6b, and 6c schematically show an LED filament device 150 including n sets of LED filaments 160. As shown, each set of the LED filaments 160 includes at least one branched LED filament 110. The branched LED filament 110 of the (k + 1)-th set of the LED filaments 160 constitutes a branch portion of the branched LED filament 110 of the k-th set of the LED filaments 160, where k represents the set of LED filaments and k = 1, 2, ···, n - 1. As a result, the sets of the LED filaments 160 can be understood to represent layers within a tree-like structure. As shown in FIGS. 6a, 6b, and 6c, this repetitive structure forms a tree-like shape in which each branch portion of the branched LED filament 110 further branches into new LED filaments 110 and the like. As shown, the length L of the LED filament 110 extending along the axis A may be of various lengths. In the embodiment shown in FIG. 6a, the length L decreases for each set of the LED filaments 160 in the tree-like shape of the LED filament device 150. The length L is preferably in the range of 2 cm to 10 cm.

[0064] FIG. 6b schematically shows a similar LED filament device in which the lengths L of each set of the tree-like structured LED filaments 160 are the same.

[0065] FIG. 6c schematically shows a similar LED filament device in which the length L of each set of the tree-shaped LED filaments 160 increases.

[0066] Thus, the length L may be utilized to create a number of shapes and structures exemplified in FIGS. 6a, 6b, and 6c.

Claims

**Claim 1**: An LED filament configuration comprising n sets of LED filaments, each LED filament comprising an array of a plurality of light-emitting diodes (LEDs) attached to a support, each LED filament being of an elongated shape and at least partially extending along an axis A, each LED filament having a branch, the LED filament being divided into at least two branches from the branch, and at least one of the at least two branches being arranged at an angle α with respect to the axis A, each LED filament comprising an encapsulant that integrally surrounds the LED filament including the at least two branches and the branch, at least one LED filament of the (k + 1)-th set of LED filaments iteratively constitutes at least one branch of the at least one LED filament of the k-th set of LED filaments for k = 1, 2,..., n - 1, whereby the n sets of LED filaments constitute a tree-like structure of LED filaments, A light-emitting diode (LED) filament configuration. **Claim 2** The LED filament configuration according to claim 1, wherein the LEDs in the array are arranged to provide a continuous light distribution over the entire LED filament including the at least two branches. **Claim 3** The LED filament configuration according to claim 1 or 2, wherein the light-emitting rows of the array of a plurality of LEDs continue through the branches. **Claim 4** The LED filament configuration according to any one of claims 1 to 3, wherein at least a first branch of the plurality of branches has a different length from a second branch of the plurality of branches. **Claim 5** The LED filament configuration according to any one of claims 1 to 4, wherein the at least one LED filament is Y-shaped. **Claim 6** The LED filament configuration according to any one of claims 1 to 5, wherein the at least one LED filament is X-shaped. **Claim 7** The LED filament configuration according to any one of claims 1 to 6, wherein at least the LEDs of at least a set of the plurality of LEDs in the LED filament are connected in series. **Claim 8** At least the LEDs of the first set of the plurality of LEDs in the LED filament and at least the LEDs of the second set of the plurality of LEDs are connected in parallel. The LED filament configuration according to any one of claims 1 to 7.

9. At least the LEDs of the first set of the plurality of LEDs and at least the LEDs of the second set of the plurality of LEDs are configured to emit light having at least one of the same color temperature and the same luminous intensity. The LED filament configuration according to any one of claims 1 to 8.

10. At least the LEDs of the first set of the plurality of LEDs and at least the LEDs of the second set of the plurality of LEDs are configured to emit light having at least one of different color temperatures and different luminous intensities. The LED filament configuration according to any one of claims 1 to 8.

11. The encapsulant includes a luminescent material and is configured to at least partially convert the light emitted by the plurality of LEDs, or the encapsulant includes a scattering material for scattering the light emitted by the plurality of LEDs. The LED filament configuration according to any one of claims 1 to 10.

12. The angle α between the at least one branch portion and the axis A is within the range of 10 to 80 degrees. The LED filament configuration according to any one of claims 1 to 11.

13. Comprising the plurality of LED filament configurations according to any one of claims 1 to 12. A light emitting diode (LED) filament unit in which the plurality of LED filament configurations are coupled such that at least the first LED filament of the plurality of LED filament configurations is physically in contact with at least the second LED filament of the plurality of LED filament configurations.

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