Light emitting device

Abstract

A light emitting diode (LED) filament lamp (100) comprises: a first LED filament (11) comprising a plurality of first LEDs (101) on a first elongate carrier (102) and electrically connected in a first circuit (103) and configured to emit first blue LED light; a second LED filament (12) comprising a plurality of second LEDs (111) on a second elongate carrier (112), and the plurality of second LEDs are electrically connected in a second circuit (113) and configured to emit a second blue LED light. The second LED filament (12) comprises a plurality of third LEDs (121) electrically connected in a third circuit (123) and configured to emit red LED light. A luminescent material covers the second elongate carrier (112), the plurality of second LEDs (111), and the plurality of third LEDs (121), the luminescent material configured to convert the second blue LED light to green converted light. The control unit (140) controls the emission of LED light from the plurality of LEDs (101, 111, 121), respectively.

Description

TECHNICAL FIELD

[0001] The present invention relates generally to light emitting devices. More specifically, the present invention relates to a light emitting diode (LED) filament lamp comprising a plurality of elongated carriers, each elongated carrier comprising a plurality of LEDs. BACKGROUND

[0002] The original bulb lamp was an electrically driven type that enclosed a metal filament within a more or less evacuated glass bulb. This type of bulb lamp has been the prevalent light source choice for over a century before the advent of LEDs. LED-based light sources have now replaced the bulb as the light source in homes and many other locations. Initially, early LED light sources (i.e. LED lamps) were not as aesthetically pleasing as the early type of bulb, mainly due to the inherent structural properties of LEDs. Therefore, for aesthetic reasons, the demand for light sources with the appearance of a traditional bulb filament lamp came back when it was found that it was technically feasible to manufacture light sources using LED filaments.

[0003] In today’s LED filament light sources, many small LEDs are mounted closely together on a wire or strip. Such a wire or strip can be configured with LEDs emitting different colors, where some of the LEDs can be embedded in a luminescent material configured to convert light emitted in a first color to another color. Thereby, it is possible to control the light output such that the output from the light source looks very much like the early metal filament bulb, and it is also possible to control the light output such that it obtains any desired color. However, a disadvantage of such LED filament light sources is that they cannot provide blue light only.

[0004] WO2021 / 073930 discloses an LED filament lamp comprising at least one LED filament having a bottom portion and a top portion extending along a longitudinal axis A over a length L, wherein the LED filament comprises an array of a plurality of LEDs extending along the longitudinal axis A. An encapsulant at least partially surrounds the plurality of LEDs, wherein the encapsulant comprises a luminescent material. The linear array of LEDs comprises N blue LEDs emitting blue light and M red LEDs emitting red light, the linear array of LEDs comprising a density of blue LEDs and a density of red LEDs. The density of blue LEDs decreases from the bottom portion to the top portion along at least a portion of the length (L) and / or the density of red LEDs increases, whereby a color temperature of light emitted from the at least one LED filament decreases from the bottom portion to the top portion over at least a portion of the length of the at least one LED filament. SUMMARY

[0005] It is of interest to provide an LED filament light source that is able to provide light of any desired color that only comprises blue light.

[0006] In a first aspect, this object and others are achieved by providing an LED filament lamp having the features of the independent claims appended hereto. Preferred embodiments are defined in the dependent claims appended hereto.

[0007] Thus, according to the present invention, there is provided an LED filament lamp providing LED filament lamp light. The LED filament lamp comprises a first LED filament comprising a plurality of first LEDs arranged on a first elongated carrier. The plurality of first LEDs are electrically connected in a first electrical circuit and configured to emit first blue LED light.

[0008] The LED filament lamp comprises a second LED filament comprising a plurality of second LEDs arranged on a second elongated carrier. The plurality of second LEDs are electrically connected in a second electrical circuit and configured to emit second blue LED light. For example, the second blue LED light can have a second peak wavelength, while the first blue LED light can have a first peak wavelength, and the absolute value of the difference between these peak wavelengths can be greater than or equal to 20 nm.

[0009] The second LED filament comprises a plurality of third LEDs arranged on the second elongated carrier. The plurality of third LEDs are electrically connected in a third electrical circuit and configured to emit red LED light.

[0010] The second LED filament comprises a first elongated encapsulant configured to at least partially cover the second elongated carrier, the plurality of second LEDs, and the plurality of third LEDs. The first elongated encapsulant comprises a first luminescent material configured to convert the second blue LED light emitted by the plurality of second LEDs into green converted light. For example, the first luminescent material of the first elongated encapsulant can be configured to convert the second blue LED light emitted by the plurality of second LEDs completely into green converted light.

[0011] The control unit is connected to the first electrical circuit, the second electrical circuit, and the third electrical circuit, and the control unit is configured to individually control the emission of the first blue LED light from the plurality of first LEDs, configured to individually control the emission of the second blue LED light from the plurality of second LEDs, and configured to individually control the emission of the red LED light from the plurality of third LEDs.

[0012] That is, such LED filament lamps comprise a first LED filament emitting blue light and a second LED filament emitting non-blue light. Due to the configuration of the LED filament lamp such that the first LED filament is separated from the second LED filament, this configuration enables the effect of providing an output of any desired color of light (including only blue light). That is, the plurality of first LEDs are not arranged on the same elongated carrier as the plurality of second LEDs and the plurality of third LEDs. The reason for this effect of outputting any desired color of light (including only blue light) is that the first elongated encapsulant comprising the first luminescent material is not excited by the blue light emitted from the first LED filament. Furthermore, by configuring the plurality of first LEDs and the plurality of second LEDs to respectively emit blue LED light having a first peak wavelength and a second peak wavelength, wherein the second peak wavelength is optimized for the maximum excitation coefficient of the first luminescent material, and wherein the first peak wavelength differs from the second peak wavelength by at least 20 nm, cross-excitation (i.e. crosstalk) of the first luminescent material by the first blue LED light can be avoided or at least minimized (to a very low extent).

[0013] Furthermore, by configuring the first luminescent material of the first elongated encapsulant to fully convert the second blue LED light emitted by the plurality of second LEDs into green converted light means that at least 97% of the second blue LED light is converted into green light by the first luminescent material.

[0014] The control unit can be configured to power only the plurality of first LEDs in the first operation mode such that the LED filament lamp light is blue light. The control unit can be configured to power only the plurality of second LEDs in the second operation mode such that the LED filament lamp light is green light. The control unit can be configured to power only the plurality of third LEDs in the third operation mode such that the LED filament lamp light is red light. The control unit can be configured to power the plurality of first LEDs, the plurality of second LEDs and the plurality of third LEDs in the fourth operation mode such that the LED filament lamp is set to emit white LED filament lamp light having a first correlated color temperature CCT1 in the range of 1500K to 6500K and a first color rendering index CRI of at least 80.

[0015] In other words, the configuration of the control unit can be such that in the first operation mode the LED filament lamp emits only light having a blue (B) intensity, in the second operation mode the LED filament lamp emits only light having a green (G) intensity, and in the third operation mode the LED filament lamp emits only light having a red (R) intensity. In the fourth operation mode the LED filament lamp emits white light having a B intensity, a G intensity and an R intensity.

[0016] Further, the control unit can be configured to power the plurality of first LEDs, the plurality of second LEDs and the plurality of third LEDs in the fifth operation mode in a different way than in the fourth operation mode, such that the LED filament lamp is set to emit white LED filament lamp light having a second correlated color temperature CCT2 in the range of 1500 K to 6500 K and a second CRI of at least 80, wherein CCT2 - CCT1 > 500 K.

[0017] In other words, the configuration of the control unit can be such that in the fifth operation mode, the LED filament lamp emits white light, wherein the intensity of B, the intensity of G and the intensity of R are different than in the fourth operation mode. For example, the intensity ratio B / (R+G) in the fifth operation mode can be higher than the intensity ratio B / (R+G) in the fourth operation mode.

[0018] The first LED filament and the second LED filament can be arranged in relation to each other such that the mutual distance D between the first LED filament and the second LED filament is at least 15 mm, preferably at least 20 mm, and optionally, D can be less than 60 mm.

[0019] By arranging the first LED filament and the second LED filament at such a distance apart from each other, it can be further ensured that the first luminescent material of the first elongated encapsulant is not excited by the light emitted from the blue LED filament emitted from the first LED filament. Thereby it is ensured that the LED filament lamp is capable of emitting light of any color, including white light as well as pure blue light. It should be noted that the minimum mutual distance of 15 mm is to be interpreted as a minimum mutual distance along all points of the first LED filament and the second LED filament. Further, by arranging the first LED filament and the second LED filament at such a distance apart from each other, an optimal viewing experience can be obtained, as the first LED filament and the second LED filament are not perceived by a viewer as a plurality of separate light sources. D can be less than 60 mm, then it is possible to obtain an optimal viewing experience, as the first LED filament and the second LED filament are not perceived by a viewer of the LED filament lamp as a plurality of separate light sources.

[0020] The first LED filament can be arranged obliquely with respect to the second LED filament, wherein the elongation axis of the first LED filament and the elongation axis of the second LED filament are not arranged in a plane.

[0021] By arranging the LED filaments obliquely, it can be further ensured that the first luminescent material of the first elongated encapsulant is not excited by the light emitted from the blue LED filament emitted from the first LED filament, and thereby it is ensured that the LED filament lamp is capable of emitting light of any color, including white light as well as pure blue light.

[0022] A second elongated encapsulant may at least partially cover the first elongated carrier and the plurality of first LEDs. The second elongated encapsulant may comprise a light scattering material configured to scatter the first blue LED light into blue scattered light. The effect obtained is an improved aesthetics and / or spatial light distribution. In such cases, the first elongated carrier may be light transmissive and the plurality of first LEDs are arranged on a first major surface of the first elongated carrier, and a further second encapsulant may at least partially cover a second major surface, which is opposite the first major surface. Such further second encapsulant may comprise a light scattering material configured to scatter the first blue LED light and / or the blue scattered light into further blue scattered light. The effect obtained is a further improved aesthetics and / or spatial light distribution.

[0023] The second plurality of LEDs and the third plurality of LEDs may be arranged on the same surface of the second elongated carrier.Alternatively, the second plurality of LEDs and the third plurality of LEDs may be arranged on respective surfaces of the second elongated carrier, eg on opposite sides of the second elongated carrier.

[0024] The second elongated carrier may be light transmissive, and the plurality of second LEDs and the plurality of third LEDs are arranged on a first major surface of the second elongated carrier. In such a configuration, the additional first encapsulant at least partially covers a second major surface of the second elongated carrier, the second major surface being opposite to the first major surface of the second elongated carrier, and the additional first encapsulant includes additional luminescent material configured to convert the second blue LED light and / or the green converted light into additional green converted light.

[0025] The first LED filament and the second LED filament may be spiral-shaped. In addition, the LED filament lamp may include N first LED filaments and M second LED filaments, where M is greater than N.

[0026] The LED filament lamp may include a housing configured to at least partially enclose a first LED filament and a second LED filament; and a connector for electrically and mechanically connecting the LED filament lamp to a socket of the lamp. An antenna may be functionally coupled to a control unit, and the control unit may be controlled by a remote user interface via the antenna to individually control the emission of a first blue LED light from the plurality of first LEDs, individually control the emission of a second blue LED light from the plurality of second LEDs, and individually control the emission of a red LED light from the plurality of third LEDs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] This and other aspects of the present invention will now be described in more detail, with reference to the accompanying drawings showing embodiment(s) of the invention.

[0028] Figure 1a schematically illustrates an LED filament lamp arranged in a lamp,

[0029] Figure 1b schematically illustrates an embodiment of a first LED filament,

[0030] Figure 1c schematically illustrates an embodiment of a first LED filament,

[0031] Figure 1d schematically illustrates an embodiment of a second LED filament,

[0032] Figure 2 schematically illustrates an embodiment of an LED filament lamp with a first LED filament and a second LED filament in a tilted configuration,

[0033] Figure 3 schematically illustrates an embodiment of an LED filament lamp with a first LED filament and a second LED filament in a helical shape,

[0034] Figure 4 schematically illustrates an embodiment of an LED filament lamp with a first LED filament and a second LED filament in a tilted configuration, and

[0035] Figure 5 schematically illustrates an embodiment of an LED filament lamp with a first LED filament and a second LED filament in a helical shape. DETAILED DESCRIPTION

[0036] As Figure 1a illustrated, an embodiment of an LED filament lamp 100 configured to provide LED filament light comprises a first LED filament 11 comprising a plurality of first LEDs 101. The plurality of first LEDs 101 is arranged on a first elongated carrier 102, and the plurality of first LEDs 101 is electrically connected in a first electrical circuit 103 and configured to emit first blue LED light, e.g. blue light having a (main) peak wavelength in the wavelength interval 430-470 nm. A second LED filament 12 comprises a plurality of second LEDs 111 arranged on a second elongated carrier 112. The plurality of second LEDs 111 is electrically connected in a second electrical circuit 113 and configured to emit second blue LED light, e.g. blue light having a (main) peak wavelength in the wavelength interval 430-470 nm. In at least one embodiment, the second blue LED light can have a second peak wavelength, while the first blue LED light can have a first peak wavelength, and the absolute value of the difference between these peak wavelengths is greater than or equal to 20 nm.

[0037] The second LED filament 12 further comprises a plurality of third LEDs 121 arranged on the second elongated carrier 112. The plurality of third LEDs 121 are electrically connected in a third circuit 123 and are configured to emit red LED light, e.g. red light having a (main) peak wavelength in any one of the wavelength intervals 610-660 nm and 620-635 nm.

[0038] The second LED filament 12 further comprises a first elongated encapsulant 130 configured to at least partially cover the second elongated carrier 112, the plurality of second LEDs 111 and the plurality of third LEDs 121. The first elongated encapsulant 130 comprises a first luminescent material configured to convert the second blue LED light emitted by the plurality of second LEDs 111 into green converted light, e.g. green light having a (main) peak wavelength in the wavelength interval 495-570 nm, e.g. 525-565 nm and 510-520 nm. For example, the first luminescent material of the first elongated encapsulant can be configured to fully, i.e. at least 97%, convert the second blue LED light emitted by the plurality of second LEDs into green converted light. It should be noted that the conversion rate depends on the particle size of the luminescent material, the thickness of the luminescent material and the concentration of particles in the luminescent material. Examples of the first luminescent material include quantum dots having a (main) peak wavelength at 530 nm and Lu3Al5O 12 :Ce 3+ (LuAG).

[0039] The control unit 140 is connected to the first circuit 103, the second circuit 113 and the third circuit 123 and is configured to individually control the emission of the first blue LED light from the plurality of first LEDs 101, to individually control the emission of the second blue LED light from the plurality of second LEDs 111 and to individually control the emission of the red LED light from the plurality of third LEDs 121.

[0040] In various embodiments of the LED filament lamp 100, the control unit 140 is configured to operate in several operation modes in which the power to the respective pluralities of LEDs 101, 111, 121 is controlled.

[0041] For example, in at least one embodiment, the control unit 140 is configured to power only the plurality of first LEDs 101 in a first operating mode so that the LED filament light is blue light, power only the plurality of second LEDs 111 in a second operating mode so that the LED filament light is green light, power only the plurality of third LEDs 121 in a third operating mode so that the LED filament light is red light, and power the plurality of first LEDs 101, the plurality of second LEDs 111, and the plurality of third LEDs 121 in a fourth operating mode so that the LED filament lamp is configured to emit white LED filament light having a first correlated color temperature CCT1 in the range of 1500 K to 6500 K and a first color rendering index CRI of at least 80. For example, in the fourth operating mode, the LED filament lamp emits white light having fourth mode B intensity, G intensity, and R intensity, respectively.

[0042] In at least one embodiment, the control unit 140 is configured to power the plurality of first LEDs 101, the plurality of second LEDs 111, and the plurality of third LEDs 121 in a different manner in the fifth operating mode than in the fourth operating mode, such that the LED filament lamp is configured to emit white LED filament light having a second correlated color temperature (CCT2) in the range of 1500K to 6500K and a second CRI (Correlation Relative Index) of at least 80, where CCT2-CCT1≥500K. For example, in the fifth operating mode, the LED filament lamp emits white light having fifth-mode B intensity, G intensity, and R intensity, respectively. Here, the ratio B / (R+G) of the fifth-mode intensity is higher than the ratio B / (R+G) of the fourth-mode intensity.

[0043] Figure 1a The first LED filament 11 and the second LED filament 12 are also shown arranged relative to one another, with a mutual distance D between the first LED filament 11 and the second LED filament 12. By arranging the first LED filament 11 and the second LED filament 12 so that D is at least 15 mm, preferably at least 20 mm, cross-excitation (i.e., crosstalk) of the blue LED filament light emitted by the first LED filament 11 into the first luminescent material of the first elongated encapsulant can be avoided or at least minimized (to a very low degree), thereby enabling pure blue light, i.e., the blue light emitted by the first LED filament 11, to be output from the LED filament lamp 100. Furthermore, by arranging the first LED filament 11 and the second LED filament 12 so that their mutual distance is less than 60 mm, it is possible to achieve an optimal viewing experience because the first LED filament 101 and the second LED filament 111 are not perceived as multiple separate light sources by a viewer of the LED filament lamp 100.

[0044] like Figure 1bAs shown, in at least one embodiment, the second elongated encapsulant 132 can at least partially cover the first elongated carrier 102 and the plurality of first LEDs 101. In such cases, the second elongated encapsulant 132 can include a light scattering material configured to scatter the first blue LED light into blue scattered light, such as a blue phosphor material including europium-doped barium orthosilicate (BOSE).

[0045] like Figure 1c As shown, in at least one embodiment, the first elongated carrier 102 is light transmissive, and the plurality of first LEDs 101 are arranged on a first major surface 141 of the first elongated carrier 102. The further second encapsulant 133 at least partially covers a second major surface 142 of the first elongated carrier 102, the second major surface being opposite the first major surface 141. In such cases, the further second encapsulant 133 may include a light scattering material configured to scatter the first blue LED light and / or the blue scattered light into further blue scattered light.

[0046] like Figure 1a and Figure 1d As shown, the plurality of second LEDs 111 and the plurality of third LEDs 121 may be arranged on the same surface of the second elongated carrier 112. However, in at least one alternative embodiment, the plurality of second LEDs 111 and the plurality of third LEDs 121 may be arranged on different surfaces of the second elongated carrier 112, for example on opposite sides of the second elongated carrier 112.

[0047] In addition, if Figure 1d As further shown, in at least one embodiment, the second elongated carrier 112 is light transmissive, and wherein the plurality of second LEDs 111 and the plurality of third LEDs 121 are arranged on a first main surface 151 of the second elongated carrier 112, and wherein an additional first encapsulant 134 at least partially covers a second main surface 152 of the second elongated carrier 112, which second main surface is opposite to the first main surface 151 of the second elongated carrier 112, and wherein the additional first encapsulant 134 includes an additional luminescent material, which is configured to convert the second blue LED light and / or the green converted light into additional green converted light.

[0048] like Figure 2As shown, in at least one embodiment, the first LED filament 11 can be arranged obliquely with respect to the second LED filament 12. The elongation axis L1 of the first LED filament 11 and the elongation axis L2 of the second LED filament 12 are not arranged in a plane. As shown, the first LED filament 11 and the second LED filament 12 are arranged in relation to each other, wherein the mutual distance between the first LED filament 11 and the second LED filament 12 is D. Due to the oblique arrangement of the LED filaments 11, 12, it is noted that the mutual distance D defines a minimum mutual distance at any point along each LED filament 11, 12.

[0049] As Figure 3 shown, in at least one embodiment, the first LED filament 11 and the second LED filament 12 are helical. Also here, as indicated, the first LED filament 11 and the second LED filament 12 are arranged in relation to each other, wherein the mutual distance between the first LED filament 11 and the second LED filament 12 is D. Due to the helical arrangement of the LED filaments 11, 12, it is noted that the mutual distance D defines a minimum mutual distance at any point along each LED filament 11, 12.

[0050] As Figure 4 and Figure 5 shown, in various embodiments, the LED filament lamp 100 can comprise a plurality of first LED filaments 11 and second LED filaments 12. For example, the LED filament lamp 100 can comprise N first LED filaments 11 and M second LED filaments 12, wherein M > N. In Figure 4 and Figure 5 , N = 1 and M = 3. For the above embodiments, the first LED filament 11 and the second LED filament 12 are arranged in relation to each other, wherein the mutual distance between the first LED filament 11 and the second LED filament 12 is D. Due to the oblique and helical arrangement of the LED filaments 11, 12 in Figure 4 and Figure 5 , respectively, it is noted that the mutual distance D defines a minimum mutual distance at any point along each LED filament 11, 12.

[0051] Now returning to Figure 1aIn at least one embodiment, the LED filament lamp 100 can comprise a housing 50 configured to at least partially enclose the first LED filament 11 and the second LED filament 12; a connector 51 for electrically and mechanically connecting the LED filament lamp 100 to a socket 61 of a luminaire 60. Further, the antenna 141 can be functionally coupled to the control unit 140, wherein the control unit 140 is configured to be controlled by the remote user interface 161 via the antenna 141 for individually controlling the emission of the first blue LED light from the plurality of first LEDs 101, for being configured to individually control the emission of the second blue LED light from the plurality of second LEDs 111, and for being configured to individually control the emission of the red LED light from the plurality of third LEDs 121. A power supply 62 can be connected to the luminaire 60, thereby providing the necessary electrical power to the LED filament lamp 100 via the socket 61. As Figure 1a As schematically illustrated in the middle, the connection between the remote user interface 161 and the control unit 140 can be implemented by standardized communication means, including an internet protocol based network 160 comprising a wireless access point 162 providing a wireless communication interface 163 via which communication can take place between the user interface 161 and the control unit 140.

[0052] The person skilled in the art realizes that the present application is in no way limited to the embodiments described above. On the contrary, many modifications and variations of the embodiments are possible within the scope of the appended claims. For example, the LED filaments 11, 12 can have a different shape, size and / or dimensions than the ones depicted / described.

Claims

1. A light emitting diode, LED, filament lamp (100) providing LED filament light and comprising: a first LED filament (11) comprising a plurality of first light emitting diodes, LEDs, (101) arranged on a first elongated carrier (102), the plurality of first LEDs (101) being electrically connected in a first electrical circuit (103) and configured to emit first blue LED light; a second LED filament (12) comprising a plurality of second LEDs (111) arranged on a second elongated carrier (112), the plurality of second LEDs (111) being electrically connected in a second electrical circuit (113) and configured to emit second blue LED light; the second LED filament (12) further comprising a plurality of third LEDs (121) arranged on the second elongated carrier (112), the plurality of third LEDs (121) being electrically connected in a third electrical circuit (123) and configured to emit red LED light; the second LED filament (12) further comprising a first elongated encapsulant (130) configured to at least partially cover the second elongated carrier (112), the plurality of second LEDs (111) and the plurality of third LEDs (121), the first elongated encapsulant (130) comprising a first luminescent material configured to convert the second blue LED light emitted by the plurality of second LEDs (111) into green converted light, a control unit (140) connected to the first electrical circuit (103), the second electrical circuit (113) and the third electrical circuit (123), and wherein the control unit (140) is configured to individually control emission of first blue LED light from the plurality of first LEDs (101), configured to individually control emission of second blue LED light from the plurality of second LEDs (111), and configured to individually control emission of red LED light from the plurality of third LEDs (121), wherein the control unit (140) is configured to: in a first operation mode, power only the plurality of first LEDs (101) such that the LED filament light is blue light; in a second operation mode, power only the plurality of second LEDs (111) such that the LED filament light is green light; in a third operation mode, power only the plurality of third LEDs (121) such that the LED filament light is red light; and in a fourth operation mode, power the plurality of first LEDs (101), the plurality of second LEDs (111) and the plurality of third LEDs (121) such that the LED filament lamp is set to emit white LED filament light having a first correlated color temperature, CCT1, in the range of 1500 K to 6500 K and a first color rendering index, CRI, of at least 80.

2. The LED filament lamp (100) according to claim 1, wherein the control unit (140) is configured to: in a fifth operation mode, differently from in the fourth operation mode, power the plurality of first LEDs (101), the plurality of second LEDs (111), and the plurality of third LEDs (121) such that the LED filament lamp is set to emit white LED filament lamp light having a second correlated color temperature CCT2 in the range of 1500 K to 6500 K and a second CRI of at least 80, wherein CCT2 - CCT1 > 500 K.

3. The LED filament lamp (100) according to any one of the preceding claims, wherein the first luminescent material of the first elongated encapsulant (130) is configured to fully convert second blue LED light emitted by the plurality of second LEDs (111) into green converted light.

4. The LED filament lamp (100) according to any one of the preceding claims, wherein the first LED filament (11) and the second LED filament (12) are arranged in relation to each other: such that a mutual distance D between the first LED filament (11) and the second LED filament (12) is at least 15 mm, preferably at least 20 mm.

5. The LED filament lamp (100) according to claim 4, wherein D is less than 60 mm.

6. The LED filament lamp (100) according to any one of the preceding claims, wherein the first LED filament (11) is arranged obliquely with respect to the second LED filament (12), and wherein an elongation axis (LI) of the first LED filament (11) and an elongation axis (L2) of the second LED filament (12) are not arranged in a plane.

7. The LED filament lamp (100) according to any one of the preceding claims, wherein a second elongated encapsulant (132) at least partially covers the first elongated carrier (102) and the plurality of first LEDs (101), the second elongated encapsulant (132) comprising a light scattering material configured to scatter the first blue LED light into blue scattered light.

8. The LED filament lamp (100) according to claim 7, wherein the first elongated carrier (102) is light transmissive, and wherein the plurality of first LEDs (101) is arranged on a first main surface (141) of the first elongated carrier (102), and wherein a further second encapsulant (133) at least partially covers a second main surface (142) opposite the first main surface (141), the further second encapsulant (133) comprising a light scattering material configured to scatter the first blue LED light and / or the blue scattered light into further blue scattered light.

9. The LED filament lamp (100) according to any one of the preceding claims, wherein the plurality of second LEDs (111) and the plurality of third LEDs (121) are arranged on a same surface of the second elongated carrier (112).

10. The LED filament lamp (100) according to any one of the preceding claims, wherein the second elongated carrier (112) is light-transmissive, and wherein the plurality of second LEDs (111) and the plurality of third LEDs (121) are arranged on a first major surface (151) of the second elongated carrier (112), and wherein a further first encapsulant (134) at least partially covers a second major surface (152) of the second elongated carrier (112), the second major surface being opposite to the first major surface (151) of the second elongated carrier (112), the further first encapsulant (134) comprising a further luminescent material configured to convert the second blue LED light and / or the green converted light into a further green converted light.

11. The LED filament lamp (100) according to any one of the preceding claims, wherein the first LED filament (11) and the second LED filament (12) are helical.

12. The LED filament lamp (100) according to any one of the preceding claims, wherein the first blue LED light has a first peak wavelength (λι) and the second blue LED light has a second peak wavelength (λ2), wherein |λ2-λι|≥ 20 nm.

13. The LED filament lamp (100) according to any one of the preceding claims, comprising N first LED filaments (11) and M second LED filaments (12), wherein M > N.

14. The LED filament lamp (100) according to any one of the preceding claims, comprising: a housing (50) configured to at least partially enclose the first LED filament (11) and the second LED filament (12); a connector (51) for electrically and mechanically connecting the LED filament lamp (100) to a socket (61) of a luminaire (60); an antenna (141) functionally coupled to the control unit (140), wherein the control unit (140) is configured to be controlled by a remote user interface (161) via the antenna (141) for individually controlling emission of the first blue LED light from the plurality of first LEDs (101), for being configured to individually control emission of the second blue LED light from the plurality of second LEDs (111), and for being configured to individually control emission of the red LED light from the plurality of third LEDs (121).

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