LED filament for illumination and disinfection

Abstract

An LED filament (100) includes: an array of a plurality of LEDs (110); a circuit (120) coupled to the plurality of LEDs; a carrier (130) arranged to support the plurality of LEDs; and an encapsulation (140) comprising a translucent material and a luminescent material configured to at least partially convert LED light into converted light, wherein the plurality of LEDs includes a first group of LEDs (150) arranged to emit first LED light in a first wavelength range of 430 nm to 490 nm, and a second group of LEDs (160) arranged to emit second LED light in a second wavelength range of 315 nm to 420 nm, wherein the circuit is configured to provide a first current I to the first group of LEDs during operation of the LED filament. c1 And provide a second current I to the second group of LEDs. c2 , where I c2 >I c1 .

Description

Technical Field

[0001] This invention generally relates to lighting devices comprising one or more light-emitting diodes (LEDs). More specifically, this invention relates to a combination of lighting that provides disinfecting (sterilizing and / or antiviral) lighting effects and aesthetically desirable (general) lighting. Background Technology

[0002] The use of light-emitting diodes (LEDs) for lighting purposes continues to receive attention. Compared to incandescent, fluorescent, and neon lamps, LEDs offer numerous advantages, such as longer operating life, reduced power consumption, and increased efficiency related to the ratio of light to heat energy. In particular, LED filament lamps are highly popular because they are very decorative.

[0003] Due to the advantages of using LEDs, interest in replacing traditional light sources with LEDs in many lighting installations has increased rapidly. It will be recognized that this replacement (also known as retrofitting) is welcomed and desired by users who want the look of incandescent bulbs. Light source replacement (retrofitting) is typically performed by removing (or replacing) traditional light sources from the luminaire (e.g., lamp holder) of the lighting installation and attaching LEDs, (or multiple LED units) or (or multiple LED devices) to the luminaire. One of these concepts is based on the LED filament placed within the bulb, as the appearance of such bulbs is desirable because they are highly decorative.

[0004] Furthermore, it is of interest to combine the advantageous properties of LED filaments for aesthetic and light distribution purposes, as described above, with the advantageous properties of disinfection (sterilization) lighting. It will be recognized that disinfection lighting has become a topic of renewed interest as the demand for sterilization increases. For example, UVA (315nm to 400nm) and / or violet light (400nm to 420nm) can be used for disinfection purposes, such as inactivating / killing bacteria.

[0005] Therefore, one object of the present invention is to combine the advantageous properties of LED filaments for aesthetic and light distribution purposes with the advantageous properties of disinfection (sterilization and / or antiviral) lighting.

[0006] WO2021 / 018606 discloses (provides) a light-emitting diode (LED) filament device. The LED filament device includes an LED filament comprising an array of multiple LEDs. The LED filament includes a first subset of at least two LEDs and a second subset of at least two LEDs, wherein the first subset of LEDs differs from the second subset of LEDs. During operation of the LED filament device, the LEDs of the first subset are series-coupled, and the LEDs of the second subset have different luminous flux than individual LEDs in the second subset. Summary of the Invention

[0007] It is of interest to combine the advantageous properties of LED filaments for aesthetic and light distribution purposes with the advantageous properties of providing disinfecting (sterilizing and / or antiviral) lighting.

[0008] This and other objectives are achieved by providing an LED filament having the features of the independent claims. Preferred embodiments are defined in the dependent claims.

[0009] Therefore, according to the present invention, a light-emitting diode (LED) filament is provided, configured to emit LED filament light. The LED filament includes an array of a plurality of LEDs configured to emit first LED light. The LED filament also includes circuitry coupled to the plurality of LEDs. The LED filament further includes a carrier arranged to support the plurality of LEDs. The LED filament also includes an encapsulation comprising a translucent material. The encapsulation also includes a luminescent material configured to at least partially convert the LED light into converted light. The encapsulation at least partially surrounds the plurality of LEDs and (and at least partially surrounds) the carrier. The plurality of LEDs includes a first group of LEDs and a second group of LEDs, the first group of LEDs being arranged to emit first LED light in a first wavelength range of 430 nm to 490 nm, and the second group of LEDs being arranged to emit second LED light in a second wavelength range of 315 nm to 420 nm. The circuitry is configured to provide a first current I to the first group of LEDs during operation of the LED filament. c1 And provide a second current I to the second group of LEDs. C2 , where I C2 >I C1 .

[0010] Therefore, the present invention is based on the concept of providing an LED filament in which a first group of LEDs is arranged to emit predominantly blue light, and a second group of LEDs is arranged to emit predominantly UV and / or violet light. Through an encapsulation, the blue light is (at least partially) converted to typical yellow and / or red light to obtain (extremely) warm white light, such as 1800K-2500K, while the UV and / or violet light provides a disinfecting effect, i.e., inactivation of bacteria. Since the conversion rate of UV and / or violet light is much lower than that of blue light, and this UV and / or violet light, which can be perceived as blue (or pale blue) light, is less visible than blue light, it is proposed to provide a higher current to the violet LEDs than to the blue LEDs. Thus, by combining blue and violet LEDs in the LED filament, and by providing different currents to the blue and violet LEDs, an LED filament is provided that can efficiently provide disinfecting lighting as well as desired lighting for lighting purposes, while being decorative and aesthetically pleasing (preferably along the length of the LED filament, i.e., across a substantially continuous color point / correlated color temperature of multiple violet and blue LEDs).

[0011] Another advantage of the present invention is that the LED filament encapsulation can provide the desired light output, including the desired (omnidirectional) light distribution, and can provide aesthetically decorative or attractive lighting effects.

[0012] It will be appreciated that, in addition, the LED filament of the present invention comprises a relatively small number of components. A relatively small number of components is advantageous because LED filaments are relatively inexpensive to manufacture. Furthermore, the relatively small number of components in an LED filament means easier recycling, especially compared to devices or apparatuses that comprise a relatively large number of components (which hinder easy disassembly and / or recycling operations).

[0013] An LED filament configured or arranged to emit LED filament light comprises an array of multiple LEDs configured or arranged to emit LED light. It will be appreciated that LED filament light may include LED light and / or LED light affected (e.g., scattered and / or converted) by the encapsulation of the LED filament. The term "array" herein means a linear arrangement or chain of LEDs arranged on the LED filament. The LED filament also includes circuitry coupled to the multiple LEDs. The term "circuitry" herein means one or more circuits configured to supply electrical power to the multiple LEDs.

[0014] The LED filament also includes a carrier arranged to support multiple LEDs. Therefore, multiple LEDs can be arranged, mounted, and / or mechanically coupled to / coupled to a carrier (e.g., a substrate), wherein the carrier is configured to mechanically support and / or electrically support the LEDs. Additionally, the carrier can be light-transmitting and / or light-reflecting. Furthermore, the carrier can be elongated to support an array of LEDs for the (elongated) LED filament.

[0015] LED filaments also include encapsulation. The term "encapsulation" herein means a material, element, device, etc., configured or arranged to at least partially surround, encapsulate, and / or surround a plurality of LEDs, a carrier, and at least one heat sink of an LED filament. The encapsulation includes a translucent material. The term "translucent material" herein means a material, component, and / or substance that is translucent and / or transparent to visible light. The encapsulation also includes a light-emitting material configured to at least partially convert LED light emitted from the plurality of LEDs into converted light. The encapsulation at least partially surrounds the plurality of LEDs and the carrier.

[0016] The plurality of LEDs includes a first group of LEDs arranged to emit first LED light in a first wavelength range of 430 nm to 490 nm. Therefore, the first group of LEDs is arranged or configured to emit first LED light that is primarily blue. The plurality of LEDs also includes a second group of LEDs arranged to emit second LED light in a second wavelength range of 315 nm to 420 nm (especially for second LED light in the second wavelength ranges of 315 nm to 360 nm and / or 400 nm to 420 nm). Therefore, the second group of LEDs is arranged or configured to emit second LED light that is primarily violet and / or ultraviolet (UV).

[0017] The circuit is configured to provide a first current I to the first group of LEDs during the operation of the LED filaments. c1 And provide a second current I to the second group of LEDs. C2 , where I C2 >I c1 Therefore, the circuitry for the LED filament is configured to supply a higher current to the violet LED compared to the blue LED during operation of the LED filament.

[0018] According to one embodiment of the present invention, the first current I c1 Second current I C2 It can satisfy I C2 >3·I C1 Therefore, the circuitry for the LED filament is configured to supply a first current I to the first group (blue) LEDs during operation of the LED filament. c1 And provide a second current I to the second group (purple) LEDs.C2 The second current I C2 Up to current I c1 At least three times, that is, I C2 >3·I C1 The advantage of this embodiment is that, since the conversion rate of UV and / or violet light is much lower than that of blue light, and since the UV and / or violet light, which can be perceived as blue (or light blue) light, is less visible than blue light, the second group of (violet) LEDs can be provided with a much higher current than the first group of (blue) LEDs. More preferably, for the second LED light in the second wavelength range of 315nm to 360nm and / or 400nm to 420nm, I... C2 >4·I C1 And most preferably, I C2 >5·I C1 .

[0019] According to one embodiment of the invention, at least two LEDs in the first group of LEDs can be coupled in parallel, and at least two LEDs in the second group of LEDs can be coupled in series. Therefore, the circuitry of the LED filament can be arranged or configured such that two or more (blue) LEDs can be coupled in parallel, and two or more (purple) LEDs can be coupled in series. An advantage of this embodiment is that the LED filament thereby achieves the function of providing a first current I to the first group of LEDs during operation of the LED filament. C1 And provide a second current I to the second group of LEDs. C2 A convenient circuit, in which I C2 >I C1 .

[0020] According to one embodiment of the present invention, the circuit may include a first circuit coupled to a first group of LEDs and a second circuit coupled to a second group of LEDs, wherein the first circuit and the second circuit are electrically isolated from each other. Therefore, the first circuit and the second circuit in the LED filament circuit can be electrically separated. An advantage of this embodiment is that providing an electrically isolated circuit with respect to the first group of LEDs and the second group of LEDs further facilitates the supply of a first current I to the first group of LEDs. C1 and supplying a second current I to the second group of LEDs C2 The operation is also convenient. This embodiment also facilitates the control of the operation of the first group of LEDs and the second group of LEDs.

[0021] According to one embodiment of the invention, the encapsulation, via its luminescent material, can be configured during the operation of an LED filament to: convert a portion of a first LED light into first converted light at a first conversion ratio R1, wherein the first converted light has a first converted light intensity Iconv1; and convert a portion of a second LED light into second converted light at a second conversion ratio R1, wherein the second converted light has a second converted light intensity Iconv2, wherein R1 / R2 > 3, preferably R1 / R2 > 5, and 0.8 < (Iconv1 / Iconv2) < 1.2. In other words, the encapsulation comprising the luminescent material can be arranged or configured to convert portions of the first LED light and the second LED light into first converted light and second converted light, respectively, at a first ratio R1 and a second ratio R2, wherein the first converted light and the second converted light have first converted light intensities Iconv1 and second converted light intensities Iconv2, respectively, wherein R1 / R2 > 3 and 0.8 < (Iconv1 / Iconv2) < 1.2. Therefore, the first converted light intensity outside the package and near the first group of LEDs is similar to or nearly similar to the second converted light intensity outside the package and near the second group of LEDs. The advantage of this embodiment is that it avoids or at least reduces the occurrence of dark areas in the LED filaments. This results in improved aesthetics and / or light distribution for the LED filaments. Furthermore, it improves the sterilization (germ-disinfecting) lighting effect of the LED filaments.

[0022] According to one embodiment of the invention, a first group of LEDs can be arranged to emit first LED light with a first LED intensity ILED1, and a second group of LEDs can be arranged to emit second LED light with a second LED intensity ILED2, wherein ILED2 > 2·ILED1. Therefore, the second (violet) LED intensity ILED2 is at least twice the first (blue) LED intensity ILED1. It should be noted that, especially at relatively low intensities, intensity deviations can be much more readily visible (e.g., LED spots) than at relatively high intensities (due to glare). Therefore, the advantage of this embodiment is that, compared to the relatively low intensity of blue LED light, the relatively high intensity of violet LED light can avoid or at least mitigate adverse effects, particularly for aesthetic purposes.

[0023] According to one embodiment of the present invention, the LED filament can be arranged to emit LED filament light having a luminous flux LF, wherein the luminous flux LF is higher than a first luminous flux threshold LF. t1In this case, the first group of LEDs is arranged to emit first LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit second LED light with a second LED intensity ILED2, where ILED1 ≤ ILED2 < 2·ILED1, and the luminous flux LF is lower than the second luminous flux threshold LF. t2 In this case, the first group of LEDs is arranged to emit first LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit second LED light with a second LED intensity ILED2, where ILED2 > 8·ILED1. Therefore, with a relatively high luminous flux FL, the second (violet) LED intensity ILED2 is higher than the first (blue) LED intensity ILED1, and can be almost twice that of the first (blue) LED intensity ILED1. Alternatively, with a relatively low luminous flux FL, the second (violet) LED intensity ILED2 can be significantly higher than the first (blue) LED intensity ILED1, as it can be more than three times that of the first (blue) LED intensity ILED1.

[0024] According to one embodiment of the invention, the second set of LEDs can be arranged to emit second LED light in a second wavelength sub-range of 400 nm to 420 nm, wherein the first luminous intensity LIB of the first LED light and the second luminous intensity LIV of the second LED light can satisfy 1.2·LIb > LIV > 0.8·LIb. Therefore, during the operation of the LED filament, much more UV and / or violet light than blue light is created, such that the first luminous intensity LIB of the first (blue) LED light can be similar to or nearly similar to the second luminous intensity LIV of the second (violet) LED light. This embodiment is advantageous because it further eliminates or even annihilates the appearance of dark areas in the LED filament during operation.

[0025] According to one embodiment of the present invention, the number of LEDs N1 in the first group of LEDs and the number of LEDs N2 in the second group of LEDs can satisfy N1 > 2·N1. Therefore, the number of LEDs N1 in the first group (blue) LEDs can be more than twice the number of LEDs N2 in the second group (purple) LEDs. It should be noted that the second group (purple) LEDs provides a relatively high light output compared to the relatively low light output of the first group (blue) LEDs. Therefore, the advantage of this embodiment is that the higher number of LEDs N1 in the first group (blue) LEDs than the number of LEDs N2 in the second group (purple) LEDs compensates for the higher light output of the second group (purple) LEDs compared to the lower light output of the first group (blue) LEDs.

[0026] According to one embodiment of the present invention, the luminescent material of the encapsulation may include at least one of YAG, LuAg, and LuYAG phosphor. Therefore, the luminescent material of the encapsulation may include yttrium aluminum garnet (YAG), lutetium aluminum garnet (LuAg), and / or lutetium-yttrium aluminum garnet (LuYAG) phosphor.

[0027] According to one embodiment of the present invention, an LED filament device is provided. The LED filament device may include one or more LED filaments according to any of the foregoing embodiments. The LED filament device may further include a controller coupled to a circuit, wherein the controller is configured to individually control the operation of a first group of LEDs and a second group of LEDs. Thus, via the controller, the circuit is configured to provide a first current I to the first group of LEDs during operation of the LED filaments. C1 And provide a second current I to the second group of LEDs. C2 , where I C2 >I C1 The advantage of this embodiment is that the controller can conveniently and efficiently control the circuit current by providing different currents to the blue LED and the purple LED, which results in the efficient provision of disinfection lighting as well as the desired lighting for lighting purposes, while being decorative and aesthetically pleasing.

[0028] According to one embodiment of the invention, the LED filament can have at least one shape selected from spiral, meandering, coil, and helical shapes. Therefore, the LED filament can be elongated in a spiral, meandering, coil, and / or helical shape. "Spiral shape" herein means that the LED filament is elongated in a coil or corkscrew shape. "Meandering shape" herein means an "S" shape, a "snake" shape, etc., in which the LED filament elongates in a plane in that shape. "Helical shape" herein means that the LED filament can twist about its own axis. It should be noted that any combination of the above examples is feasible, such as a combination of spiral and helical shapes. The advantage of this embodiment is that the configuration(s) of the LED filaments can achieve efficient emission of LED filament light and realize decorative LED filaments during their operation.

[0029] According to one embodiment of the present invention, the LED filament light can be white light with a correlated color temperature (CCT) below 2500K. The advantage of this embodiment is that the white light from the LED filament appears "warm" during operation and can further contribute to the aesthetics of the LED filament light.

[0030] According to one embodiment of the present invention, an LED filament device is provided. The LED filament device includes at least one LED filament according to any of the foregoing embodiments, and a controller coupled to a circuit, wherein the controller is configured to individually control the operation of a first group of LEDs and a second group of LEDs. In this embodiment, the controller of the LED filament device is configured via the circuitry of the LED filament to provide a first current L to the first group of LEDs during operation of the LED filament. C1 And provide a second current I to the second group of LEDs. C2 , where I C2 >L C1 The advantage of this embodiment is that the controller can conveniently and efficiently control the distribution of current in the circuit, which results in highly efficient disinfection lighting and desired lighting for lighting purposes, while also being decorative and aesthetically pleasing.

[0031] According to one embodiment of the invention, a controller can be configured to individually control the operation of a first group of LEDs and a second group of LEDs by at least one of the following: increasing the first intensity ILED1 of the first group of LEDs and increasing the second intensity ILED2 of the second group of LEDs such that 0 ≤ ILED1 ≤ 0.5·ILED2, and decreasing the first intensity ILED1 of the first group of LEDs and decreasing the second intensity ILED2 of the second group of LEDs such that 0 ≤ ILED1 ≤ 0.5·ILED2. Therefore, the controller can be configured to increase and / or decrease the first intensity ILED1 and the second intensity ILED2, wherein during the increase and decrease of the first intensity ILED1 of the first group (blue) LEDs, the controller is configured to maintain the second intensity ILED2 of the second group (purple) LEDs higher than the first intensity ILED1 of the first group (blue) LEDs.

[0032] According to one embodiment of the present invention, an LED lighting device is provided. The LED lighting device may include one of the following: an LED filament according to any of the foregoing embodiments, and an LED filament arrangement according to any of the foregoing embodiments. The LED lighting device also includes a cover comprising at least partially transparent material, wherein the cover at least partially surrounds the LED filament. The LED lighting device further includes an electrical connector connected to the LED filament to supply power to a plurality of LEDs of the LED filament. The term "cover" herein refers to an enclosing element comprising at least partially translucent and / or transparent material, such as a cap, cover, housing, etc. An advantage of this embodiment is that the LED filament according to the present invention can be conveniently arranged in substantially any lighting LED lighting device (such as an LED filament lamp or LED filament luminaire, lamp, lighting system, etc.). The LED lighting device may also include a driver for supplying power to the LEDs of the LED filament. Additionally, the lighting device may also include a controller for individually controlling a first group of LEDs and a second group of LEDs.

[0033] Further objects, features, and advantages of the invention will become apparent upon studying the following detailed disclosure, drawings, and appended claims. Those skilled in the art will recognize that different features of the invention can be combined to create embodiments different from those described below. Attached Figure Description

[0034] 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.

[0035] Figure 1 An LED filament lamp according to the prior art is schematically shown, which includes an LED filament.

[0036] Figures 2a to 2c An LED filament according to an exemplary embodiment of the present invention is schematically shown.

[0037] Figure 3a The relative intensity of LED filament light during operation of the LED filament according to an exemplary embodiment of the present invention is schematically disclosed.

[0038] Figure 3b The luminous flux LF of an LED filament during operation according to an exemplary embodiment of the present invention is schematically disclosed.

[0039] Figure 4 An LED filament device according to an embodiment of the present invention is illustrated schematically.

[0040] Figure 5 An LED lighting device according to an exemplary embodiment of the present invention is schematically illustrated, and

[0041] Figure 6 The diagram schematically illustrates the radiation measurement power of a UV / violet LED according to an embodiment of the present invention, or the radiation measurement power of an LED emitting at 450 nm. Detailed Implementation

[0042] Figure 1 An LED filament lamp 10 according to the prior art is shown, which includes a plurality of LED filaments 20. Such LED filament lamps 10 are highly popular because they are very decorative and offer many advantages over incandescent lamps, such as longer operating life, reduced power consumption, and increased efficiency related to the ratio between light and heat energy.

[0043] Figure 2a An LED filament 100 according to an exemplary embodiment of the present invention is schematically shown. The LED filament 100, extending along axis A, is configured to emit LED filament light 105. The LED filament light 105 emitted from the LED filament 100 during operation is preferably white light with a correlated color temperature (CCT) below 2500 K. This white light preferably has a color rendering index (CRI) of at least 80. The length L of the LED filament 100 is... f The width W of the LED filament 100 is preferably in the range of 1cm to 20cm, more preferably in the range of 2cm to 12cm, and most preferably in the range of 3cm to 10cm. f The aspect ratio L is preferably in the range of 0.5 mm to 10 mm, more preferably in the range of 0.8 mm to 8 mm, and most preferably in the range of 1 mm to 5 mm. f / W f Preferably at least 5, more preferably at least 8, and most preferably at least 10.

[0044] The LED filament 100 includes an array or "chain" of a plurality of LEDs 110 configured to emit LED light. For example, the array or "chain" of the plurality of LEDs 110 may include a plurality of LEDs 110 arranged adjacent to each other. The plurality of LEDs 110 preferably includes more than 5 LEDs, more preferably more than 8 LEDs, and even more preferably more than 10 LEDs.

[0045] The LED filament 100 also includes a carrier 130 arranged to support a plurality of LEDs 110. The plurality of LEDs 110 may be arranged, mounted, and / or mechanically coupled to / to the carrier 130. The carrier 130 (e.g., a substrate) is configured to mechanically support and / or electrically support the plurality of LEDs 110. The carrier 130 may be a printed circuit board (PCB). The carrier 130 may be light-transmitting and / or light-reflecting. Furthermore, the carrier 130 may be flexible and may, for example, comprise a polymer foil (e.g., polyimide (PI), polyethylene terephthalate (PET), etc.). The carrier 130 may include one or more thermally conductive layers and one or more insulating layers.

[0046] exist Figure 2a In this embodiment, the LED filament 110 also includes an encapsulation 140. The encapsulation 140 comprises a translucent material. Furthermore, the encapsulation 140 includes a light-emitting material configured to at least partially convert light emitted from the plurality of LEDs 120 into converted light. The encapsulation 140 may include a light-scattering material configured to scatter light emitted from the plurality of LEDs 120. The light-scattering material may preferably have a reflectivity >70%, more preferably >80%, and most preferably >85%. The encapsulation 140 may be flexible. Additionally, the encapsulation 140 may include silicone. The encapsulation 140, via its light-emitting material, can be configured during operation of the LED filament 100 to: convert a portion of the first LED light into first converted light at a first conversion ratio R1, wherein the first converted light has a first converted light intensity Iconv1 (not shown); and convert a portion of the second LED light into second converted light at a second conversion ratio R1, wherein the second converted light has a second converted light intensity Iconv2 (not shown), wherein R1 / R2>3 and 0.7<(Iconv1 / Iconv2)<1.3, preferably 0.8<(Iconv1 / Iconv2)<1.2.

[0047] exist Figure 2a In this embodiment, the encapsulation 140 at least partially surrounds the plurality of LEDs 110 and the carrier 130. For example, and as shown in... Figure 2aAs indicated, the package 140 completely surrounds the plurality of LEDs 110. Because the length and / or width of the carrier 130 may be longer and / or wider than the length and / or width of the LED filaments 110, the package 140 partially surrounds the carrier 130. The LED filament light 105 may thereby comprise LED light and / or converted light. The luminescent material of the package 140 is configured to emit light upon excitation by external energy. For example, the luminescent material may comprise a fluorescent material. The luminescent material may comprise inorganic phosphors, organic phosphors, and / or quantum dots / rods. More specifically, and according to one embodiment of the invention, the luminescent material of the package may comprise yttrium aluminum garnet (YAG), LuAg, and / or LuYAG phosphors. UV / blue LED light may be partially or completely absorbed by the luminescent material and converted into another color (e.g., green, yellow, orange, and / or red) light.

[0048] Figure 2b This schematically illustrates an exemplary embodiment of the invention. Figure 2a The LED filament is 100, and reference is made. Figure 2a To enhance understanding of the characteristics and / or operation of the LED filament 100. The plurality of LEDs 110 includes a first group of LEDs 150, which are configured to emit light in a first wavelength range of 430 nm to 490 nm. Therefore, the first group of LEDs 150 is arranged to emit predominantly blue light. The plurality of LEDs 110 also includes a second group of LEDs 160, which are configured to emit light in a second wavelength range of 315 nm to 420 nm. Therefore, the second group of LEDs 150 is arranged to emit violet or ultraviolet (UV) light. According to... Figure 2b In the example shown, the number of LEDs N1 in the first group of LEDs 150 and the number of LEDs N2 in the second group of LEDs 160 can satisfy N1>2·N2, preferably N1>3·N2.

[0049] exist Figure 2b In this configuration, the LED filament 100 also includes circuitry 120 coupled to a plurality of LEDs 110. Circuitry 120 is configured to provide a first current I to a first group of LEDs 150 during operation of the LED filament 100. c1 Circuit 120 is also configured to provide a second current I to the second group of LEDs 160 during operation of the LED filament 100. C2 During operation, the LED filament 100 is configured to supply a greater current to the second group of LEDs 160 (i.e., the purple LEDs) than to the first group of LEDs 150 (i.e., the blue LEDs 150), causing I... C2 >I C1 For example, the first current I C1 Second current IC2 It can satisfy I C2 >3·I C1 Circuit 120 may include a first circuit 120a coupled to a first group of LEDs 150 and a second circuit 120b coupled to a second group of LEDs 160. The first circuit 120a and the second circuit 120b may be electrically isolated from each other.

[0050] Figure 2c It was disclosed in a suggestive manner. Figure 2b The circuit 120 of the LED filament 100 includes Figure 2a and / or Figure 2b The LED filament 100 has a first group of LEDs 150 and a second group of LEDs 160. Here, at least two LEDs in the first group of LEDs 150 are coupled in parallel, and at least two LEDs in the second group of LEDs 160 are coupled in series. Therefore, as Figure 2b The circuit 120 of the LED filament 100 illustrated herein is via Figure 2c The example is arranged or configured such that two or more (blue) LEDs are coupled in parallel. It will be recognized that... Figure 2c Two branches of the parallel coupling are disclosed, but virtually any number of branches can be provided to the parallel coupling. Furthermore, via... Figure 2c For example, the circuit 120 of the LED filament 100 is arranged or configured such that two or more (purple) LEDs are coupled in series. Through this arrangement of circuit 120, which couples a first group of LEDs 150 in parallel and a second group of LEDs 160 in series, the LED filament 100 can provide a first current I to the first group of LEDs 150 during operation of the LED filament 100. C1 And a second current I is supplied to the second group of LEDs 160. C2 , where I C2 >I C1 According to one example, circuit 120 is configured to provide a first current I per unit epitaxial pn junction area to the first group of LEDs 150 during operation of the LED filament. C1 And provide a second current I per unit epitaxial pn junction to the second group of LEDs 160. C2 , where I C2 >I C1 This results in the power emitted per unit area by the second group of LEDs 160 (second radiation measurement) being higher than the power emitted per unit area by the first group of LEDs 150 (first radiation measurement).

[0051] It should be noted that Figures 2a to 2cAn exemplary embodiment of the LED filament(s) 110 is shown, and the shape and / or number of the LED filament(s) may differ from those shown. For example, the LED filament(s) 100 may have a spiral, meandering, coil, and / or helical shape.

[0052] Figure 3a The relative intensity of LED filament light during operation of an LED filament according to an example of the invention is schematically disclosed. In this specific example, the light-emitting material of the LED filament encapsulation comprises YAG Ce phosphors according to wavelength. Figure 3a The excitation spectrum 170 and emission spectrum 175 of the LED filament light are shown, where arrow 180 indicates the distribution of the first (blue) LED light and arrow 190 indicates the wavelength of the second (purple) LED light.

[0053] Figure 3b The luminous flux LF is schematically disclosed as a function of the intensity of a first LED light and a second LED light in the LED filament light during operation according to an example of the present invention, expressed in arbitrary units. The LED filament is arranged to emit LED filament light having a luminous flux LF. When the luminous flux LF is higher than a first luminous flux threshold LF... t1 That is, LF > LF t1 In this case, the first group of LEDs is arranged to emit a first (blue) LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit a second (purple) LED light with a second LED intensity ILED2, where ILED1 ≤ ILED2 < 2·ILED1, as indicated on the right-hand side of the figure. When the luminous flux LF is below the second luminous flux threshold LF... t2 LF <LF t2 In this case, the first group of LEDs is arranged to emit a first (blue) LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit a second (purple) LED light with a second LED intensity ILED2, wherein ILED2 > 2·ILED1, preferably ILED2 > 3·ILED1. Therefore, at a relatively high luminous flux FL, the second (purple) LED intensity (light power per unit emitting area) ILED2 is higher than the first (blue) LED intensity (light power per unit emitting area) ILED1, and can be almost twice that of the first (blue) LED intensity ILED1. Alternatively, at a relatively low luminous flux FL, the second (purple) LED intensity ILED2 can be significantly higher than the first (blue) LED intensity ILED1, as it can be more than three times that of the first (blue) LED intensity ILED1. It will be recognized that the first luminous flux threshold LF... t1 Second luminous flux threshold LFt2 They can have the same value, or alternatively, they can have different values.

[0054] Figure 4 An LED filament device 200 according to an embodiment of the present invention is schematically shown. The LED filament device 200 includes at least one LED filament 100 according to any of the foregoing embodiments. It should be noted that reference... Figures 2a to 2c To enhance understanding of the characteristics and / or functions of the LED filament 100. The LED filament device 200 also includes a controller 210 of circuitry coupled to the LED filament 100, wherein the controller 210 is configured to individually control the operation of a first group of LEDs and a second group of LEDs of the LED filament 100.

[0055] Figure 5 An LED lighting device 500 according to an embodiment of the present invention is schematically illustrated. The LED lighting device 500, which may constitute a lamp or luminaire, includes one or more LED filaments 110 according to any of the foregoing embodiments. The LED lighting device 500 also includes a cover 510, illustrated as being in the shape of a bulb. The cover 510 may include at least partially light-transmitting (e.g., transparent) material, and the cover 510 at least partially surrounds the LED filaments 100. The LED lighting device 500 also includes an electrical connector 520 connected to the LED filaments 100 to supply power to a plurality of LEDs of the LED filaments 100.

[0056] Figure 6 The diagram schematically illustrates the radiation measurement power of a UV / violet LED / radiation measurement power of an LED emitting at 450 nm according to an embodiment of the invention, for obtaining the same lumen output of a first group of LEDs and a second group of LEDs through a phosphor in the package.

[0057] 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. For example, one or more of the LED filament 100, carrier 130, encapsulation 140, etc., may have a shape, size, and / or size different from those depicted / described.

Claims

1. A light-emitting diode (LED) filament (100) configured to emit LED filament light (105), said LED filament comprising: An array of multiple light-emitting diodes (LEDs) (110) configured to emit LED light, The circuit (120) coupled to the plurality of LEDs, Carrier (130), which is arranged to support the plurality of LEDs, An encapsulation (140) comprising a translucent material and a light-emitting material, the light-emitting material being configured to at least partially convert the light from the LEDs into converted light, wherein the encapsulation at least partially surrounds the plurality of LEDs and the carrier. The plurality of LEDs includes a first group of LEDs (150) arranged to emit first LED light in a first wavelength range of 430 nm to 490 nm, and a second group of LEDs (160) arranged to emit second LED light in a second wavelength range of 315 nm to 420 nm. The circuit is configured to provide a first current I to the first group of LEDs during operation of the LED filaments. c1 And provide a second current I to the second group of LEDs. C2 , where I C2 >I c1 ,and The encapsulation is configured via its light-emitting material to, during operation of the LED filament A portion of the first LED light is converted into first converted light with a first conversion ratio R1, wherein the first converted light has a first converted light intensity Iconv1; and a portion of the second LED light is converted into second converted light with a second conversion ratio R2, wherein the second converted light has a second converted light intensity Iconv2. Where R1 / R2>3 and 0.7<(Iconv1 / Iconv2)<1.

3.

2. The LED filament according to claim 1, wherein the first current I c1 and the second current I C2 Satisfy I C2 >3·I c1 .

3. The LED filament according to claim 1 or 2, wherein at least two LEDs in the first group of LEDs are coupled in parallel, and wherein at least two LEDs in the second group of LEDs are coupled in series.

4. The LED filament according to claim 1 or 2, wherein the circuit includes a first circuit (120a) coupled to the first group of LEDs and a second circuit (120b) coupled to the second group of LEDs, wherein the first circuit and the second circuit are electrically isolated from each other.

5. The LED filament according to claim 1 or 2, wherein the first group of LEDs is arranged to emit the first LED light having a first LED intensity ILED1, and wherein the second group of LEDs is arranged to emit the second LED light having a second LED intensity ILED2, wherein ILED2>2·ILED1.

6. The LED filament according to claim 1 or 2, wherein the LED filament is arranged to emit LED filament light having a luminous flux LF, wherein When the luminous flux LF is higher than the first luminous flux threshold LF t1 In this case, The first group of LEDs is arranged to emit first LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit second LED light with a second LED intensity ILED2, wherein ILED1 ≤ ILED2 < 2·ILED1, and When the luminous flux LF is lower than the second luminous flux threshold LF t2 In this case, The first group of LEDs is arranged to emit a first LED light with a first LED intensity ILED1, and the second group of LEDs is arranged to emit a second LED light with a second LED intensity ILED2, wherein ILED2>8·ILED1.

7. The LED filament according to claim 1 or 2, wherein the second group of LEDs is arranged to emit second LED light in a second wavelength subrange of 400 nm to 420 nm, wherein the first luminous intensity LIb of the first LED light and the second luminous intensity LIv of the second LED light satisfy 1.2·LIb>LIv>0.8·LIb.

8. The LED filament according to claim 1 or 2, wherein the number N1 of LEDs in the first group of LEDs and the number N2 of LEDs in the second group of LEDs satisfy N1>2·N2.

9. The LED filament according to claim 1 or 2, wherein the light-emitting material of the encapsulation comprises at least one of YAG, LuAg, and LuYAG phosphor.

10. The LED filament according to claim 1 or 2, wherein the LED filament has at least one shape selected from spiral, meandering, coil and helical shapes.

11. The LED filament according to claim 1 or 2, wherein the LED filament light is white light having a correlated color temperature (CCT) of less than 2500K.

12. The LED filament according to claim 1, wherein 0.8 < (Iconv1 / Iconv2) < 1.

2.

13. An LED filament device (200), comprising: At least one LED filament according to claim 1 or 2, and A controller (210) coupled to the circuit, wherein the controller is configured to control the operation of the first group of LEDs and the second group of LEDs separately.

14. The LED filament device of claim 13, wherein the controller is configured to individually control the operation of the first group of LEDs and the second group of LEDs by at least one of the following: Increase the first intensity ILED1 of the first group of LEDs, and Increase the second intensity ILED2 of the second group of LEDs such that 0 ≤ ILED1 ≤ 0.5·ILED2, and Reduce the first intensity ILED1 of the first group of LEDs and reduce the second intensity ILED2 of the second group of LEDs, such that 0≤ILED1≤0.5·ILED2.

15. An LED lighting device (500), comprising one of the following: - The LED filament according to claim 1 or 2, wherein the LED lighting device further comprises: A cover (510) comprising at least partially transparent material, wherein the cover at least partially surrounds the LED filament; and electrical connectors (520) connected to the LED filament to supply power to the plurality of LEDs of the LED filament, and - The LED filament device according to claim 13 or 14, wherein the LED lighting device further comprises: a cover (510) comprising a material that is at least partially transparent, wherein the cover at least partially surrounds the LED filament; And an electrical connector (520) connected to the LED filament to supply power to the plurality of LEDs of the LED filament.

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