LED filament lamp

Abstract

The LED filament lamp (1) includes: a plurality of elongated LED filaments (2), the plurality of elongated LED filaments (2) being adapted to emit LED filament light (16) during operation; and a solid, transparent, elongated rod-shaped element (3), the rod-shaped element (3) including a plurality of elongated cavities (4), wherein at least one of the plurality of elongated LED filaments (2) (21-24) is arranged in each of the plurality of elongated cavities (4) (41-44), each of the plurality of elongated cavities (4) (41-44) including a angular cross-sectional shape, the angular cross-sectional shape including at least three facets (61-64), the at least three facets Each pair of converging facets in (61-64) forms a corner (51-55). Each elongated cavity (41-44) in the plurality of elongated cavities (4) is arranged such that adjacent elongated cavities (41, 42) are in contact at most through the corresponding corners (54, 55), and the adjacent facets (65, 66) of the adjacent elongated cavities (4) extend at an angle α to each other, the angle α satisfying the relation α≥2arcsin(n0 / n1), where n0 is the refractive index of the medium present in each of the plurality of elongated cavities (4), and n1 is the refractive index of the material of the solid, transparent, elongated rod-shaped element (3).

Description

Technical Field

[0001] This invention relates to an LED filament lamp comprising a plurality of elongated LED filaments adapted to emit LED filament light during operation. Background Technology

[0002] LED filaments are attractive and widely used due to their high efficiency, and are therefore particularly used in energy-class A lighting products that provide over 210 lm / W. Currently, there is a strong desire to combine LED filaments with other LEDs (e.g., RGB LEDs) in LED applications such as (smart) LED bulbs (HUE products), TLEDs, and lighting for offices and retail locations.

[0003] There is a persistent drive to improve the system efficiency (lm / W) of LED-based systems. A relatively new type of LED is the LED filament, which is frequently and exclusively used in LED lamps (“bulbs”). An LED filament is a long, rod-shaped emitter (typically 30nm-50mm in length and 1mm-3mm in diameter) that emits light across its entire surface area (comparable to a fluorescent tube). An LED filament can consist of a linear array of blue LED dies on a substrate, covered by a layer of blue light-converting material (“phosphor”). This specific construction results in LED filaments achieving high efficiencies of up to approximately 230lm / W.

[0004] More generally, an LED filament provides 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, where L > 5W. The LED filament can be arranged in a straight configuration or in a non-straight configuration (such as, for example, a curved configuration, a 2D / 3D spiral, or a helical shape). Preferably, the LED is arranged on an elongated carrier, which can be, for example, a rigid carrier (made of, for example, polymer, glass, quartz, metal, or sapphire) or a flexible carrier (e.g., made of polymer or metal, for example, a film or foil).

[0005] In the case where the carrier comprises a first main surface and an opposing second main surface, the LED is disposed on at least one of these surfaces. The carrier may be reflective or translucent (such as translucent, and preferably transparent).

[0006] As used herein, the terms carrier and elongated carrier are used interchangeably, so that an elongated carrier can also simply be referred to as a carrier.

[0007] LED filaments may include an encapsulation that at least partially covers at least a portion of a plurality of LEDs. The encapsulation may also at least partially cover at least one of a first main surface and a second main surface. The encapsulation may be a polymer material, which may be flexible, such as, for example, silicone. Furthermore, the LEDs may be arranged to emit LED light of, for example, different colors or spectra. The encapsulation may include a light-emitting material configured to convert at least a portion of the LED light into converted light. The light-emitting material may be a phosphor, such as an inorganic phosphor and / or quantum dots or quantum rods (QDs).

[0008] LED filaments can include multiple sub-filaments.

[0009] US 8,066,419 B2 discloses a lighting device. The lighting device includes a light guide plate and at least one array of light-emitting diodes (LEDs) housed in holes arranged in the light guide plate, wherein each hole has: at least two side facets through which light from the LEDs is laterally coupled into the light guide plate; and at least one corner formed by two converging side facets of the at least two side facets.

[0010] Typical LED filament bulbs use 2 to 12 filaments, which constitutes a large total phosphor area. This large phosphor area means that blue light emitted by a single filament can be absorbed by all adjacent filaments and converted into yellow light (this is especially important when the filaments are close together). Absorption can also occur without conversion during this process. Another problem arises when the filaments are combined with additional RGB LED packages in, for example, smart, color-tunable bulbs. In this case, the blue light from the RGB LED package is partially converted at the large phosphor surface of the filament. As a result, the bulb cannot produce a saturated blue. However, another problem arises when the light interacts with wires, cables, PCBs, etc. These interactions create optical losses and should be avoided.

[0011] In addition, the densely packed LED filaments in, for example, LED bulbs suffer from power loss and color point drift due to the optical interactions between the filaments.

[0012] Therefore, there is a need to provide LED filament lamps with high-density LED filament light sources. With LED filament lamps, a compact optical solution can be obtained to place the filament and other LEDs close to each other without generating interactions / crosstalk between the sources. Summary of the Invention

[0013] The purpose of this invention is to overcome this problem and provide an LED filament lamp with a high-density LED filament light source. With the LED filament lamp, a compact optical solution can be obtained for placing the filament and other LEDs close to each other without generating interactions / crosstalk between the sources.

[0014] According to a first aspect of the invention, this and other objectives are achieved by means of an LED filament lamp comprising: a plurality of elongated LED filaments adapted to emit LED filament light in operation; and at least one solid, transparent, elongated rod-shaped element comprising a plurality of elongated cavities, wherein at least one of the plurality of elongated LED filaments is arranged in each of the plurality of elongated cavities, wherein each of the plurality of elongated cavities comprises a convex corner cross-sectional shape comprising at least three facets, wherein every two of the at least three facets converge to form a corner, wherein each of the plurality of elongated cavities is arranged such that adjacent elongated cavities contact each other at most through a corresponding corner, and wherein the adjacent facets of adjacent elongated cavities extend from each other at an angle α, the angle α satisfying the relation α≥2arcsin(1 / n), where n is the refractive index of the material of the solid, transparent, elongated rod-shaped element.

[0015] Thus, and specifically by ensuring that each of the multiple elongated cavities is arranged such that adjacent elongated cavities contact each other at most through their respective corners, and specifically by ensuring that the adjacent facets of the adjacent elongated cavities extend at an angle α to each other, the angle α satisfying the relationship α≥2arcsin(n0 / n1), where n0 is the refractive index of the medium present in each of the multiple elongated cavities, and n1 is the refractive index of the material of the solid, transparent, elongated rod-shaped element, an LED filament lamp with high-density LED filament light source is provided. With the LED filament lamp, a compact optical solution can be obtained for placing the filament and other LEDs close to each other without generating interactions / crosstalk between sources or with very little interaction / crosstalk.

[0016] The solid, transparent, elongated rod-shaped element also includes an outer periphery, and the opposing sides or side segments of the outer periphery can be provided with multiple prism elements.

[0017] This provides another LED filament lamp that exhibits high optical efficiency.

[0018] The angular cross-sectional shape of each of the multiple elongated cavities can be a square or a rectangle, the rectangle having a width a and a length b, and the cross-sectional shape of the prism element among the multiple prism elements can be a right-angled triangle with right-angled sides of different lengths, wherein the angle φ between the longest right-angled side and the hypotenuse is defined as φ=arctan(a / b), and the angle β between the shortest right-angled side and the hypotenuse is defined as β=90–φ.

[0019] Additionally, the prism elements among the multiple prism elements can have a height h, which is defined as h = b. sin(φ).

[0020] Such a choice of prism element geometry has proven to produce LED filament lamps with exceptionally high optical efficiency.

[0021] The angular cross-sectional shape of each of the multiple elongated cavities can be a square or a rectangle with a diameter L1, and the cross-sectional shape of the prism element among the multiple prism elements is a right-angled triangle with a hypotenuse of length L2, where L2 is less than L1.

[0022] Choosing L2 to be smaller (and possibly even much smaller) than L1 results in LED filament lamps having a flat and compact structure, while also having exceptionally high optical efficiency.

[0023] L1 can be in the range of 1mm-5mm, and L2 can be in the range of 10µm-500µm.

[0024] Such a choice of size has proven to produce LED filament lamps with exceptionally high optical efficiency.

[0025] The angular cross-sectional shape of each of the multiple elongated cavities can be any of the following: polygonal, triangular, square, hexagonal, and rectangular.

[0026] This choice of elongated cavity shape has proven to produce LED filament lamps with particularly low crosstalk between elongated cavities.

[0027] Solid, transparent, slender rod-shaped elements may have cross-sectional shapes that are circular, rectangular, square, elliptical, ring-shaped, polygonal, regular polygonal, or irregular.

[0028] Thus, and depending on the cross-sectional shape chosen for the rod-shaped element, LED filament lamps with various intensity distributions according to the invention can be provided while still avoiding interaction / crosstalk between sources.

[0029] The gap can be provided between at least one elongated LED filament and at least one facet of the elongated cavity on which the elongated LED filament is arranged.

[0030] This provides an LED filament lamp with exceptionally low crosstalk between elongated cavities.

[0031] Each of the multiple elongated cavities can be arranged such that adjacent elongated cavities contact each other through corresponding corners of at least three corresponding corners.

[0032] This leads to the development of LED filament lamps, which minimize the space occupied by each slender cavity.

[0033] The gap can be set between at least two adjacent elongated cavities.

[0034] Thus, LED filament lamps according to the invention can be provided that have various asymmetric or non-constant intensity distributions in at least one plane, while still avoiding interactions / crosstalk between sources. Such intensity distributions can be specifically used in applications where it is desired to illuminate a defined area, while other adjacent areas should not be illuminated.

[0035] The slender cavities in a plurality of slender cavities may all have the same cross-sectional dimensions.

[0036] Thus, an LED filament lamp according to the invention can be provided that has a highly symmetrical or constant intensity distribution in at least one plane, while still avoiding interactions / crosstalk between sources. Such an intensity distribution can be specifically used in applications where uniform illumination of a defined area is desired.

[0037] Alternatively, the elongated cavities in a plurality of elongated cavities may include at least two different cross-sectional dimensions.

[0038] Thus, LED filament lamps with various intensity distributions according to the present invention can be provided while still avoiding interactions / crosstalk between sources.

[0039] Only one of the multiple elongated LED filaments can be arranged in each of the multiple elongated cavities.

[0040] This provides an LED filament lamp with exceptionally high optical efficiency.

[0041] LED filament lamps may also include at least one additional elongated cavity, which may contain electronic components.

[0042] Therefore, the fact that electronic components, which are necessary for driving and controlling LED lamps and LED lighting, can be arranged such that there is no or very little crosstalk between cavities can be used to ensure that the electronic components do not affect the path of light emitted by multiple LED filaments. Furthermore, it is ensured that the light emitted by multiple LED filaments does not affect (e.g., cause heating) the electronic components.

[0043] At least one of the elongated LED filaments in the plurality of elongated LED filaments may be an elongated LED filament suitable for emitting blue LED filament light during operation.

[0044] Thus, an LED filament lamp is obtained, wherein light from an LED filament adapted to emit blue LED filament light in operation cannot excite a phosphor from an adjacent LED filament adapted to emit white light (especially warm white light) in operation.

[0045] The materials for solid, transparent, slender rod-shaped elements can be selected from the group including PMMA, polycarbonate, glass, quartz glass and sapphire / TGA (Al2O3).

[0046] Therefore, especially in terms of extremely low light loss in solid, transparent, slender rod-shaped elements, the solid, transparent, slender rod-shaped elements themselves have almost no effect on the final LED filament light.

[0047] The cross-sectional shape of each of the multiple elongated LED filaments can be any one of the following: circular, elliptical, rectangular with or without rounded corners, and square with or without rounded corners.

[0048] The present invention also relates to luminaires including LED filament lamps according to the present invention.

[0049] It should be noted that the present invention relates to all possible combinations of the features described in the claims. Attached Figure Description

[0050] This and other aspects of the invention will now be described in more detail with reference to the accompanying drawings, which illustrate multiple embodiments of the invention.

[0051] Figure 1 A cross-sectional schematic diagram of an LED filament lamp according to the present invention is shown.

[0052] Figure 2 It shows according to Figure 1 A perspective view of an LED filament lamp.

[0053] Figure 3 A schematic cross-sectional view of an exemplary LED filament is shown.

[0054] Figure 4 It shows according to Figure 1 A cross-sectional schematic diagram of an LED filament lamp, in which the central LED filament is turned on and a ray tracing simulation is shown.

[0055] Figure 5 It shows according to Figure 1 A cross-sectional schematic diagram of an LED filament lamp, in which the external LED filament is turned on and a ray tracing simulation is shown.

[0056] Figure 6 It shows according to Figure 1 The intensity distribution diagram of the light emitted by the LED filament lamp.

[0057] Figure 7 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0058] Figure 8 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0059] Figure 9 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0060] Figure 10 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0061] Figure 11 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0062] Figure 12 and Figure 13 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0063] Figure 14 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0064] Figure 15 A cross-sectional schematic diagram of another LED filament lamp according to the present invention is shown.

[0065] Figure 16 A luminaire comprising an LED filament lamp according to the present invention is shown.

[0066] As illustrated in the figures, the dimensions of the layers and regions are exaggerated for illustrative purposes and are therefore provided to illustrate the overall structure of embodiments of the invention. Throughout the figures, the same reference numerals refer to the same elements. Detailed Implementation

[0067] The invention will now be described more fully with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to thoroughly and completely convey the scope of the invention to those skilled in the art.

[0068] Figure 1 A cross-sectional schematic diagram of the LED filament lamp 1 according to the present invention is shown. Figure 2 It shows according to Figure 1 A perspective view of the LED filament lamp 1.

[0069] Typically, and not related to this invention, an LED filament lamp 1 includes a plurality of elongated LED filaments 2 and at least one solid, transparent, elongated rod-shaped element 3.

[0070] Multiple thin LED filaments 2 are adapted to emit LED filament light 16 during operation (see...) Figure 4 and Figure 5 Multiple elongated LED filaments 2 include at least two LED filaments 21-24. Figure 1 In the illustrated embodiment, three LED filaments 21-23 are provided. See also... Figure 3 Each LED filament 2 includes a light-transmitting elongated carrier 201 and multiple LEDs 200.

[0071] Multiple LEDs 200 are arranged on a first main surface 206 of the carrier 201. The multiple LEDs 200 may include, for example, RGB LEDs optionally combined with warm white and / or cool white LEDs. At least one of the elongated LED filaments 2 may be adapted to emit blue LED filament light in operation, that is, blue LEDs may be included.

[0072] The LED filament 2 may further include a first elongated package 202. The first elongated package 202 is arranged to cover a plurality of LEDs 200. The first elongated package 202 may include a first light-emitting material 204. The first light-emitting material 204 is configured to at least partially convert first LED light emitted by the plurality of LEDs 200 into first converted light. Alternatively or additionally, the first elongated package 202 may include a first light-scattering material 205. The first light-scattering material 205 is configured to at least partially scatter the first LED light emitted by the plurality of LEDs 200 into first scattered light.

[0073] The LED filament 2 may further include a second encapsulation 203. The second encapsulation 203 is disposed on the second main surface 207 of the carrier 201. The second encapsulation 203 may be the same as or different from the first encapsulation 202. The second encapsulation 203 may include a second light-emitting material (not shown). The second light-emitting material is configured to at least partially convert the first LED light emitted by the plurality of LEDs into second converted light. Alternatively or additionally, the second encapsulation 203 may include a second light-scattering material (not shown). The second light-scattering material is configured to at least partially scatter the first LED light emitted by the plurality of LEDs 200 into second scattered light.

[0074] Refer again Figure 1 and Figure 2 A solid, transparent, elongated rod-shaped element 3 includes multiple elongated cavities 4. The multiple elongated cavities 4 include at least two elongated cavities 41-44. Figure 1 In the illustrated embodiment, three elongated cavities 41-43 are provided. At least one elongated LED filament 21-24 of a plurality of elongated LED filaments is arranged in each of the plurality of elongated cavities 41-44. Figure 1 In the embodiment shown, exactly one elongated LED filament 21-23 is arranged in each elongated cavity 41-43.

[0075] Optionally, the gap 11 can be provided in at least one elongated LED filament (see [reference]). Figure 1 LED filament 23) and elongated cavity (see Figure 1 The elongated cavity 43 contains an elongated LED filament 23 arranged between at least one facet of its surface. A gap 11 may be provided between one or more facets of the surface and the elongated LED filament. The gap 11 may be provided on all sides of the elongated LED filament, or only around a portion of its periphery. The gap 11 may be provided over the entire length of the elongated LED filament or over a portion of its length.

[0076] The solid, transparent, elongated rod-shaped element 3 can be made of, for example, PMMA, polycarbonate, glass, quartz glass, or sapphire / TGA (Al2O3). The rod-shaped element 3 can consist of two parts as indicated by either of the two dashed lines D1 and D2. Thus, the rod-shaped element 3 can be easily manufactured, for example, by injection molding.

[0077] Each of the plurality of elongated cavities 4, 41-43, includes a angular cross-sectional shape comprising at least three facets 61-64. The angular cross-sectional shape of each elongated cavity 41-43 may be convex or concave. The angular cross-sectional shape of each elongated cavity 41-43 may be polygonal, such as, for example, a triangle (see...). Figure 14 ), hexagon (see Figure 15 Any of the following: a square, a rectangle, or a square. Figure 1 In the illustrated embodiment, the corner cross-sectional shape of each cavity 41-43 is square, and the elongated cavities 41-43 all include the same cross-sectional dimensions. The elongated cavities 41-43 may also all include the same cross-sectional dimensions over their entire length. Every two converging facets of a single cavity with at least three facets (or in other words, every two facets of a single cavity that come together from different directions to eventually meet, also referred to as (paired) adjacent facets, e.g., facets 61 and 64 of cavity 41) form corners 51-55. Figure 1 In the embodiment shown, each cavity 41-43 therefore includes four facets 51-54 and four corners 61-64.

[0078] Each elongated cavity 41-43 is arranged such that adjacent elongated cavities 41, 42 contact each other only through corresponding corners 54, 55. Adjacent facets of adjacent elongated cavities 4 (e.g., facets 65 and 66) extend at an angle α to each other. Angle α is typically chosen to satisfy the relationship α ≥ 2arcsin(n0 / n1), where n0 is the refractive index of the medium present in each of the plurality of elongated cavities 4, and n is the refractive index of the material of the solid, transparent, elongated rod-shaped element 3. In the case where the medium present in each of the plurality of elongated cavities 4 is air (specifically, atmosphere), n0 equals 1, and then angle α is chosen to satisfy the relationship α ≥ 2arcsin(1 / n). However, each of the plurality of elongated cavities 4 may also be filled with a medium other than atmosphere (such as, for example, an inert gas), in which case n0 differs from 1, depending on the chosen medium.

[0079] The solid, transparent, elongated rod-shaped element 3 also includes an outer periphery 7. The solid, transparent, elongated rod-shaped element 3 includes a cross-sectional shape, which can be circular, rectangular, square, elliptical, annular, polygonal, regular polygonal, or irregular. More generally, the cross-sectional shape of the rod-shaped element 3 can be formed or selected to achieve a specific far-field intensity distribution. Figure 1 and Figure 2 In the example, the square cross-sectional shape of the rod element 3 is used.

[0080] Figure 4 It shows according to Figure 1A cross-sectional schematic diagram of the LED filament lamp 1, wherein the central LED filament 22 is turned on, while the outer LED filaments 21 and 23 are turned off. Figure 4 The ray tracing simulation of this situation is also illustrated. As can be seen, all rays of LED light 17 emitted by the central LED filament 22 are prevented from entering the adjacent cavities where the outer LED filaments 21 and 23 are arranged. More specifically, the rays of LED light 17 incident on the facets of the adjacent cavities where the outer LED filaments 21 and 23 are arranged are reflected back from the facets. Finally, the rays of LED light 17 leave the rod-shaped element 3 at the outer periphery 7 and are emitted as LED filament light 16.

[0081] Figure 5 It shows according to Figure 1 A cross-sectional schematic diagram of an LED filament lamp, wherein the outer LED filament 23 is turned on, while the relatively outer LED filament 21 and the central LED filament 22 are turned off. Figure 5 The ray tracing simulation of this situation is also illustrated. As can be seen, all rays of LED light 17 emitted by the external LED filament 23 are prevented from entering the adjacent cavities where LED filaments 21 and 22 are arranged. More specifically, rays of LED light 17 incident on the facets of the adjacent cavities where LED filaments 21 and 22 are arranged are reflected back from the facets. Finally, the rays of LED light 17 exit the rod-shaped element 3 at the outer periphery 7 and are emitted as LED filament light 16.

[0082] Therefore, in both cases, the interaction or crosstalk between the corresponding LED filaments can be seen to be effectively avoided. It should be noted that... Figure 4 and Figure 5 The simulations were performed without considering Fresnel reflection at the interface between the rod element 3 and the surrounding air. If Fresnel reflection is considered, there is a very small interaction between the two adjacent sources. A key metric is the system's optical efficiency. If we assume all three LED filaments 21-23 have 100% absorption and the same flux and spectral properties, and neglect Fresnel reflection, the system's optical efficiency is 100%. When Fresnel reflection is considered, the system's optical efficiency is 90.5%.

[0083] Figure 6 It shows according to Figure 1 and Figure 2 The diagram shows the intensity distribution of light emitted by the LED filament lamp 1. The diagram illustrates the intensity distribution 13 in the XY plane and the intensity distribution 14 in the YZ plane. As can be seen, the square cross-sectional shape of the rod-shaped element 3 produces an almost constant intensity distribution 14 in the YZ plane.

[0084] Figure 7A cross-sectional schematic diagram of another embodiment of the LED filament lamp 100 according to the present invention is shown. Figure 7 The LED filament lamp 100 shown above is related to the above. Figure 1 and Figure 2 The LED filament lamps described are distinguished by the following features.

[0085] The LED filament lamp 100 includes four elongated cavities 41-44 and four LED filaments 21-24. Although according to Figure 1 The cavities 41-43 of the LED filament lamp 1 are arranged in a line, but the cavities 41-44 of the LED filament lamp 100 are arranged such that one cavity 44 is laterally displaced relative to the other three cavities 41-43.

[0086] When switched on, LED filament 22 does not interact with LED filaments 21, 23, and 24. When LED filament 22 is a suitable LED filament for emitting blue light (or a linear array including SMD LEDs), and LED filaments 21, 23, and 24 are LED filaments for emitting warm white light (e.g., 4000K), the light emitted by LED filament 22 cannot excite the phosphors of LED filaments 21, 23, and 24. However, the interaction between LED filaments 21 and 24, and between LED filaments 23 and 24, will be very limited.

[0087] Figure 8 A cross-sectional schematic diagram of another embodiment of the LED filament lamp 101 according to the present invention is shown, wherein the LED filament is not shown for simplicity. Figure 8 The LED filament lamp 101 shown above is related to the above. Figure 1 , Figure 2 and Figure 7 The LED filament lamps described are distinguished by the following features.

[0088] The LED filament lamp 101 illustrates that elongated cavities 41-43 typically include at least two different cross-sectional dimensions. In the illustrated embodiment, elongated cavity 42 includes a larger cross-sectional dimension compared to elongated cavities 41 and 43.

[0089] In addition, gap 12 is provided between at least two adjacent elongated cavities (in the illustrated embodiment, between elongated cavities 42 and 43).

[0090] Figure 9 A cross-sectional schematic diagram of another embodiment of the LED filament lamp 102 according to the present invention is shown. Figure 9 The LED filament lamp 102 shown above is related to the above. Figure 1 , Figure 2 , Figure 7 and Figure 8The LED filament lamps described are distinguished by the following features.

[0091] The LED filament lamp 101 illustrates elongated cavities 41-43, which typically include at least two different cross-sectional shapes. In the illustrated embodiment, elongated cavity 42 includes a rectangular cross-sectional shape, while elongated cavities 41 and 43 include square cross-sectional shapes.

[0092] The LED filament lamp 101 is also illustrated to include one or more elongated cavities (here elongated cavity 42) that may include more than one (here two) LED filaments 22 and 22'.

[0093] Figure 10 A cross-sectional schematic diagram of another embodiment of the LED filament lamp 103 according to the present invention is shown. Figure 10 The LED filament lamp 103 shown above is related to the above. Figure 1 , Figure 2 and Figures 7 to 9 The LED filament lamps described are distinguished by the following features.

[0094] The LED filament lamp 103 illustrates that one or more additional elongated cavities 45 can be provided. Figure 10 In the illustrated embodiment, an additional elongated cavity 45 is provided. This additional elongated cavity 45 can be used to house the electronic components 15 of the LED filament lamp 103. In this way, interaction or crosstalk between the light emitted by the LED filaments 21 and 22 and the electronic components 15 can be effectively avoided. The electronic components 15 can be, for example, wiring 152 for supplying power to the LED filaments 21 and 22, and a controller 151 for controlling the LED filaments 21 and 22 (and specifically, parameters related to the LED filament light emitted by the LED filaments 21 and 22).

[0095] The LED filament lamp 103 also illustrates that LED filaments 21 and 22 typically include at least two different cross-sectional shapes. In the illustrated embodiment, LED filament 21 includes a circular cross-sectional shape, while LED filament 22 includes an oval or elliptical cross-sectional shape. Figure 11 A cross-sectional schematic diagram of another embodiment of the LED filament lamp 104 according to the present invention is shown. Figure 11 The LED filament lamp 104 shown above is related to the above. Figure 1 , Figure 2 and Figures 7-10 The LED filament lamps described are distinguished by the following features.

[0096] Figure 11The LED filament lamp 104 shown includes a 3x3 array of solid, transparent, elongated rod-shaped elements 3a, 3b, 3c, and 3d. Rod-shaped element 3d is a robust, elongated rod-shaped element without any cavities containing LED filaments. Rod-shaped elements 3a, 3b, and 3c each include four elongated cavities 4a, 4b, and 4c and four LED filaments 2a, 2b, and 2c, respectively, arranged in a line. The four elongated cavities 4a and 4c and the four LED filaments 2a and 2c are arranged in corresponding lines extending parallel to each other. The four elongated cavities 4b and the four LED filaments 2b are arranged in lines rotated ninety degrees relative to the four elongated cavities 4a and 4c and relative to the four LED filaments 2a and 2c, respectively. To form an integral elongated rod-shaped element with a square cross-sectional shape, three elongated rod-shaped elements 3a, 3b, and 3c are arranged or sandwiched between six elongated rod-shaped elements 3d (three on each side).

[0097] Furthermore, the corresponding elongated rod-shaped elements 3a, 3b, 3c, and 3d can be separated from each other by an air gap, preventing them from optically contacting each other. The width of this air gap can be less than 10 µm.

[0098] Figure 12 and Figure 13 A cross-sectional schematic diagram of another embodiment of the LED filament lamp 105 according to the present invention is shown. Figure 12 and Figure 13 The LED filament lamp 105 shown above is related to the above. Figure 1 , Figure 2 and Figures 7-11 The LED filament lamps described are distinguished by the following features.

[0099] The LED filament lamp 105 includes an optical element 8. The optical element 8 is arranged on the outer periphery 7 of the rod-shaped element 3. More specifically, the optical element 8 is arranged on the opposing sides 71, 72 or side segments of the outer periphery 7 of the rod-shaped element 3. The general purpose of the optical element 8 is to restore or improve the optical efficiency of the LED filament lamp 105.

[0100] The rod-shaped element 3 of the LED filament lamp 105 can be composed of two parts 31 and 32. Thus, the rod-shaped element 3 can be easily manufactured, for example, by injection molding.

[0101] As shown in the figure, the optical element 8 includes multiple prism elements 81 and 82. Furthermore, the corner cross-sectional shape of each elongated cavity 41 in the plurality of elongated cavities 4 is square or (e.g., ...). Figure 12 and Figure 13 (As shown in the diagram) A rectangle having a width a and a length b. Each of the plurality of elongated cavities 41 also includes a diameter L1.

[0102] The cross-sectional shapes of the prism elements 81, 82 are the cross-sectional shapes of right-angled triangles having a hypotenuse 10 and right-angled sides 91, 92 of different lengths. The angle φ between the longest right-angled side 92 and the hypotenuse 10 is selected such that φ = arctan(a / b). The angle β between the shortest right-angled side 91 and the hypotenuse 10 is selected such that β = 90 – φ. The third angle is a right angle. The prism elements 81, 82 among the plurality of prism elements 8 also have a height h, and the height h is selected such that h = b sin(φ). Further, the hypotenuse 10 has a length L2, and the length L2 is selected such that L2 < L1. As an example, L1 can be in the range of 1 mm – 5 mm, and L2 can be in the range of 10 µm – 500 µm.

[0103] Return reference Figure 4 and Figure 5 it has been shown that when such an optical element 8 is provided and the Fresnel reflection is considered, the optical efficiency is 90.5%, and for Figure 12 and Figure 13 the specific construction shown in is even 90.9%. When the optical element 8 is removed, the optical efficiency drops to 76.8%.

[0104] Finally turning to Figure 14 an exemplary luminaire in the form of a pendant luminaire 400 is shown. The pendant luminaire 400 includes an LED filament lamp 1; 100 - 105 according to any embodiment of the present invention. As Figure 14 shown in, the LED filament lamp 1; 100 - 105 is provided in the form of a bulb 300.

[0105] The bulb 300 further includes a transparent housing 301 that at least partially envelopes at least one LED filament lamp 1; 100 - 105. The transparent housing 301 can be shaped into any feasible shape, such as in the shape similar to any one of a standard bulb, a spherical bulb, a candle bulb, a custom bulb, or even a spiral bulb. The transparent housing 301 can include a light-emitting material. The transparent housing 301 can be a glass housing.

[0106] The bulb 300 further includes a base 303, such as a lamp cap. The transparent housing 301 is connected to or mounted on the base 303. The base 303 is configured to electrically and mechanically connect the LED filament lamp 1; 100 - 105 to the socket 401 of the luminaire. The transparent housing 301 can include a neck, and in the case where the neck is provided, the neck forms the part where the transparent housing 301 is connected or attached to the base 303.

[0107] The bulb 300 may also include a thread 302 for connecting to a socket and a terminal 304 for connecting to an electrical source. The thread 302 and the terminal 304 may form part of the base 303 or be disposed on the base 303.

[0108] LED filament lamps 1; 100-105 may also optionally include a driver or controller (see...). Figure 10 The controller 151, or driver or controller, is configured to control the LED filament lamps 1; 100-105. The driver or controller 151 may be an external unit, a unit arranged within the LED filament lamps 1; 100-105, or a combination of both.

[0109] The pendant luminaire 400 also includes a socket 401 for connecting a bulb 300 (and thus an LED filament lamp 1; 100-105) to the pendant luminaire 400. The socket 401 is adapted to mate with the base 303 of the bulb 300. The socket 401 may include threads adapted to mate with threads 302 of the bulb 300. The socket 401 may include terminals adapted to mate with terminals 304 of the bulb 300.

[0110] The pendant luminaire 400 may further include a driver 402 configured to control LED filament lamps 1; 100-105. The driver 402 may or may not be the same unit as the controller 151 described above. In other words, the driver 402 and controller 151 may be integrated into the same driver or controller, or they may be independent units. The driver 402 is configured to supply power to a plurality of LED filaments 21-24 via conductive wires of the LED filament lamps 1; 100-105. The driver 402 may also be configured to control at least one of the CCT and CRI of the LED filament lamp light 17. The driver 402 may also be configured to control other parameters related to the LED filament lamp light source (i.e., the plurality of LEDs 200 of LED filaments 21-24), the plurality of LED filaments 21-24, and the LED filament light 16.

[0111] like Figure 14 As shown, the driver 402 is disposed on the reflector or lampshade 403 of the pendant luminaire 400. The driver may also be disposed within or incorporated into the reflector or lampshade 403. The pendant luminaire 400 also includes electrical wiring 404 for connection to a power source, such as mains power.

[0112] It should be noted that Figure 14The suspended luminaire 400 shown is merely one example of a luminaire according to the invention. Any suitable type of luminaire can be contemplated, such as, but not limited to, floor luminaires, wall-mounted luminaires, chandeliers, reading lamps, outdoor luminaires, and table lamps.

[0113] LED filament lamps (1; 100-105) are suitable for a wide range of LED lighting applications. Currently, LED filaments are widely used in LED bulbs. For example, ... Figure 12 and Figure 13 The LED filament lamp 105 shown can be used in LED bulbs with high LED counts and / or very limited crosstalk. The LED filament lamp 1;100-105 according to the invention also allows for the combination of conventional SMD LEDs and one or more LED filaments (e.g., the LED filaments can be placed on top of an SMD LED array). Furthermore, the invention relates to TLEDs (LED replacements for fluorescent tubes) and lighting for office and retail applications.

[0114] Those skilled in the art will recognize that the present invention is by no means limited to the preferred embodiments described above. Rather, many modifications and variations are possible within the scope of the appended claims.

[0115] Additionally, through a study of the accompanying drawings, disclosure, and appended claims, those skilled in the art can understand and implement variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude multiple. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that combinations of these measures cannot be advantageously used.

Claims

1. An LED filament lamp (1), comprising: Multiple slender LED filaments (2) are adapted to emit LED filament light (16) during operation, and At least one solid, transparent, elongated rod-shaped element (3) includes a plurality of elongated cavities (4), wherein at least one elongated LED filament (21-24) of the plurality of elongated LED filaments is arranged at least partially or entirely in each elongated cavity (41-44) of the plurality of elongated cavities, wherein Each of the plurality of elongated cavities (4) includes a convex corner cross-sectional shape, the convex corner cross-sectional shape including at least three facets (61-64), and every two of the at least three facets converging facets forming a corner (51-55), wherein Each of the plurality of elongated cavities (4) is arranged such that adjacent elongated cavities (41, 42) contact each other at most through their respective corners (54, 55), and wherein The mutually adjacent facets (65, 66) of the mutually adjacent elongated cavities (4) extend at an angle a to each other, said angle a satisfying the relationship a > 2 arcsin(n0 / n1), where n0 is the refractive index of the medium present in each of the plurality of elongated cavities (4), and n1 is the refractive index of the material of the solid, transparent, elongated rod-like element (3).

2. The LED filament lamp according to claim 1, wherein the solid, transparent, elongated rod-shaped element (3) further includes an outer periphery (7), and wherein the opposing sides (71, 72) or side segments of the outer periphery are provided with a plurality of prism elements (8).

3. The LED filament lamp according to claim 2, wherein... The angular cross-sectional shape of each of the plurality of elongated cavities (4) is a square or a rectangle, wherein the rectangle has a width a and a length b, and wherein The cross-sectional shape of the prism element (81, 82) among the plurality of prism elements is a right triangle with right-angled sides (91, 92) of different lengths, wherein the angle φ between the longest right-angled side (92) and the hypotenuse (10) is defined as φ=arctan(a / b), and wherein the angle β between the shortest right-angled side (91) and the hypotenuse (10) is defined as β=90–φ.

4. The LED filament lamp according to claim 2 or 3, wherein... The angular cross-sectional shape of each of the plurality of elongated cavities (4) is a square or rectangle with a diameter L1, wherein The cross-sectional shape of the prism element (8) among the plurality of prism elements is a right-angled triangle with a hypotenuse (10) having a length L2, and wherein L2 <L1。 5. The LED filament lamp according to claim 4, wherein L1 is in the range of 1 mm to 5 mm, and wherein L2 is in the range of 10 µm to 500 µm.

6. The LED filament lamp according to any one of the preceding claims, wherein the angular cross-sectional shape of each of the plurality of elongated cavities (4) is any one of a polygon, a hexagon, a triangle, a square, and a rectangle.

7. The LED filament lamp according to any one of the preceding claims, wherein the solid, transparent, elongated rod-shaped element (3) includes a cross-sectional shape that is circular, rectangular, square, elliptical, annular, polygonal, regular polygonal, or irregular.

8. The LED filament lamp according to any one of the preceding claims, wherein the gap (11) is disposed between at least one elongated LED filament (23) and at least one facet of the elongated cavity (43) on which the elongated LED filament (23) is disposed.

9. The LED filament lamp according to any one of the preceding claims, wherein each of the plurality of elongated cavities (4) is arranged such that adjacent elongated cavities (41, 42) contact each other through corresponding corners (54, 55) of at least three corresponding corners, or wherein The gap (12) is provided between at least two adjacent elongated cavities (42, 43).

10. The LED filament lamp according to any one of the preceding claims, wherein the elongated cavities in the plurality of elongated cavities (4) all have the same cross-sectional dimensions, or wherein... The elongated cavities (4) of the plurality of elongated cavities include at least two different cross-sectional dimensions.

11. The LED filament lamp according to any one of the preceding claims, wherein only one of the plurality of elongated LED filaments (2) is arranged in each of the plurality of elongated cavities (4).

12. The LED filament lamp according to any one of the preceding claims, comprising at least one additional elongated cavity (45), said additional elongated cavity comprising electronic components (15).

13. The LED filament lamp according to any one of the preceding claims, wherein at least one of the elongated LED filaments (2) is an elongated LED filament adapted to emit blue LED filament light in operation.

14. The LED filament lamp according to any one of the preceding claims, wherein the solid, transparent, elongated rod-shaped element (3) is made of a material selected from the group consisting of PMMA, polycarbonate, glass, quartz glass and sapphire / TGA (Al2O3).

15. A luminaire (400) comprising an LED filament lamp (1) according to any one of the preceding claims.

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