Lighting device

Abstract

A lighting device comprises a combination of a plurality of white light emitting normal-sized LEDs and a plurality of white light emitting RGB micro-LEDs that functions as a single white light source. The plurality of M-LEDs are arranged in a group of M-LEDs and confined within an area, A, and the plurality of N-LEDs are arranged outside the area, A.

Description

[0001] LIGHTING DEVICE

[0002] FIELD OF THE INVENTION

[0003] The present invention generally relates to lighting devices configured to provide device light. More specifically, the present invention is related to a lighting device comprising a first white light emitting diode (LED) light source and a second white LED light source.

[0004] BACKGROUND OF THE INVENTION

[0005] A trend in the development of LED lighting is the development of lighting arrangements capable of providing white light having any desired color temperature. For this purpose, the lighting arrangements are configured with a combination of LED’s.

[0006] White phosphor-converted (pc) LEDs are based on blue LEDs covered by an encapsulant comprising a green and red phosphor. White pc-LEDs are combined with direct- emitting (de) Red, Green and Blue LEDs, for example combined into a single LED package for LED strips. In combination with a controller which is configured to individually control the different LEDs, the color temperature can be varied allowing correlated color temperature (CCT) control.

[0007] US2021 / 1376200A1 discloses a flash LED package includes a substrate, a flash LED device in a first region of an upper surface of the substrate, and including first to fourth LED light sources that emit white light, blue light, green light, and red light, respectively. An optical sensor in provided a second region of the upper surface of the substrate, and having a light receiving region that detects a correlated color temperature. A lens cover is provided on the substrate to cover the flash LED device and the optical sensor, wherein the lens cover has a lens unit in a region overlapping the first to fourth LED light sources.

[0008] EP2815438A discloses a light emitting device package that includes a substrate, a first light emitting chip disposed on the substrate, a plurality of second light emitting chips disposed on the outer circumference of the first light emitting chip, and a lens formed on the first and the second light emitting chips. US2019 / 057954A discloses a light emitter device including a submount with a top surface and a bottom surface, electrically conductive traces on the top surface of the submount and light emitting diodes (LEDs) arranged on the top surface of the submount in light emitter zones. The LEDs are being electrically connected to respective traces of the traces, a retention material is disposed over the top surface of the submount in a form of walls which physically separate the light emitter zones. Encapsulants are dispensed in respective light emitter zones of the light emitter zones. The LEDs are individually addressable to independently control an output of light from each of the LEDs to produce a specified light output.

[0009] EP2398079A a lighting apparatus includes a red LED, a green LED, a blue LED and a white LED made up of a blue light-emitting element and a yellow phosphor. The red LED, the green LED, the blue LED, and the white LED generate 26 to 38%, 35 to 50%, 0 to 2%, and 12 to 33% of light, respectively. White light is obtained by additive color mixing of light from the red, green, blue, and white LEDs has a correlated color temperature of 2800 K or more to less than 3500 K, a deviation of 0.02 or below in absolute value, and a color gamut area ratio of 120% or more to 140% or less.

[0010] KR20110102062 A discloses a combination of a first LED light source unit having at least one first white LED and emitting white light of a first color temperature, and a second LED light source unit having at least one second white LED and emitting white light of a second color temperature different from the first color temperature Light source unit. A variable resistor is connected to at least one of the first LED light source unit and the second LED light source unit to adjust a current supplied to at least one of the first LED light source unit and the second LED light source unit.

[0011] However, a remaining issue is a desire to improve the quality of white light and / or efficiency of such LED light sources.

[0012] SUMMARY OF THE INVENTION

[0013] It is of interest to provide a lighting device that overcomes drawbacks of the prior art as discussed above.

[0014] This and other objects are achieved in a first aspect by providing a lighting device having the features of the appended independent claim. Preferred embodiments are defined in the appended dependent claims.

[0015] Hence, according to the present invention, there is provided a lighting device configured to provide device light. The lighting device comprises a carrier. A first white LED light source is arranged on the carrier and configured to provide first white LED light source light. A second white LED light source is arranged on the carrier and configured to provide second white LED light source light. The first white LED light source comprises at least one first light emitting diodes, N-LED. Each of the N-LEDs comprises a die having a first surface area, SAI, wherein the SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers. The second white LED light source comprises a plurality of second light emitting diodes, M-LEDs. Each of the M-LEDs comprises a die having a second surface area, SA2, wherein the SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers. A ratio, Rl, defined by SA1 / SA2 is equal to or larger than 10. The first and second surface areas may also be denoted as light output areas of the dies.

[0016] The plurality of M-LEDs are arranged in a group of M-LEDs and confined within an area, A. The plurality of N-LEDs are arranged outside the area, A. The plurality of M-LEDs comprise a plurality of red M-LEDs providing red M-LED light, a plurality of green M-LEDs providing green M-LED light, and a plurality of blue M-LEDs providing blue M- LED light. The red M-LEDs provide red M-LED light and may have a peak wavelength in a wavelength range from 600 nm to 680 nm, especially in a wavelength range from 610 nm to 640 nm. The green M-LEDs provide green M-LED light and may have a peak wavelength in a wavelength range from 500 nm to 580 nm, especially in a wavelength range from 520 nm to 560 nm. The blue M-LEDs provide blue M-LED light and may have a peak wavelength in a wavelength range from 430 nm to 490 nm, especially in a wavelength range from 440 nm to 470 nm.

[0017] The second LED light source light comprises the red M-LED light, the green M-LED light and the blue M-LED light. The second white LED light source light is white light having a second correlated color temperature, CCT2, in a range from 1700K to 6500K or 2700K to 6500K or 2700K to 6500K and optionally having a color render index, CRI2, of at least 70 or at least 80.

[0018] In other words, such a lighting device is a combination of a white light emitting LED package of normal-sized LEDs and a white light emitting package with RGB micro-LEDs that functions as a single white light source. Such a configuration provides an improved color over angle (COA) compared to a pc-white LED, which is especially important when combined with an optic such as a total internal reflection (TIR) optic. It may also enable an improved control of the CCT of the white light. In an embodiment, the area, A, has a surface area of equal to or smaller than 10 mm2, preferably equal to or smaller than 8 mm2, more preferably equal to or smaller than 2 mm2. For example, the area A has the dimension of 2x2 mm, such as 1x1 mm.

[0019] The M-LEDs in the group of M-LEDs may be arranged at a pitch Pl, and the first and second white LED light sources may be arranged at a pitch P2, wherein P2>2P1 or P2>5P1.

[0020] With such a factor between the pitches (noting that pitch means the distance between neighboring LEDs) of the M-LEDs and the first and second white LED light sources, it is possible to improve mixing of the colored light emitted by the different M- LEDs. The smaller the LEDs, the smaller the gap between the LEDs.

[0021] Each of the at least one N-LEDs may comprise a white phosphor-converted LED comprising a blue LED and a converter comprising a green-yellow phosphor configured to at least partly convert blue light emitted by the blue LED into green-yellow converted light and an orange-red phosphor configured to at least partly convert the blue light emitted by the blue LED and / or at least partly convert said green-yellow converted light into orange-red converted light.

[0022] The obtained effect of such a configuration is improved light quality, and especially improved CRI.

[0023] Alternatively, each of the at least one N-LEDs may comprise at least one red N-LED configured to provide red N-LED light, at least one green N-LED configured to provide green N-LED light and at least one further blue N-LED configured to provide blue N-LED light.

[0024] In other words, RGB N-LEDs are provided on the carrier which is a partitioning configuration allowing optimal control of the different colors, especially in an active manner i.e. color point or correlated color temperature control.

[0025] In such configurations, the first LED light source light may be white light having a first correlated color temperature, CCT1, in a range from 1700 K to 6500 K, preferably 2700 K to 6500 K, more preferably 2700 K to 4500 K and optionally having a color render index, CRI1, of at least 70 or at least 80 and, optionally, CCT2>CCTl+500K. That is, two different white LED light sources are combined providing the benefits of both technologies i.e. Normal LEDs and MicroLEDs.

[0026] In embodiments wherein the N-LEDs comprise at least one red N-LED and at least one further blue N-LED, these may be direct-emitting LEDs. This is advantageous because these LEDs provide a narrow band emission providing light at tuned particular wavelengths. It may also be more efficient because the blue and red LEDs may not be covered by a phosphor (no back reflection due to the phosphor).

[0027] In embodiments wherein the N-LEDs comprise at least one green N-LED, these green N-LEDs may comprise a blue LED and a converter comprising a further greenyellow phosphor configured to at least partly convert further blue N-LED light emitted by said further blue N-LED into further green-yellow converted light. Such a configuration provides a higher light quality. Phosphor converted green light has typically a larger FWHM which benefits the yellow and green colors in the white light. Such configuration may also be more efficient because green direct-emitting LEDs are less efficient than phosphor converted green LEDs. The reason is that the blue LED are very efficient and green phosphor as well.

[0028] With regard to the ratio of the number of N-LEDs and M-LEDs, the number of M-LEDs may be denoted X, the number of N-LEDs may be denoted Y, and wherein X may be greater than or equal to 5 times Y. Due to the size of the M-LEDs the number of LEDs that can be used is very high. The advantage of this is for example higher reliability.

[0029] Malfunctioning of a single M-LED has little or no impact on the total light.

[0030] In some embodiments, the lighting device may comprise only one red N-LED, only one blue N-LED and only one green N-LED. An RGB configuration is used for generating white light which is advantageous in that it is rather cost effective given the die area.

[0031] With regard to surface area ratios, TSAI may be defined as total surface area of all N-LEDs, TSA2 may be defined as a total surface area of all M-LEDs and a ratio, R2, defined by TSA1 / TSA2 may be equal or greater than 2 or may be equal or greater than 3. A higher TSAI area with respect to the TSA2 area may reduce a total assembly cost since the assembly cost of the M-LEDs is relatively high.

[0032] The carrier may be a printed circuit board (PCB) comprising circuits configured to provide electric connections between the M-LEDs and a driver, and configured to provide electric connections between the N-LEDs and the driver. The PCB may comprise a metal core. The metal core of the PCB may be a monolithic.

[0033] The plurality of M-LEDs may be covered by an optical element configured to collimate the second white LED light source light. Preferably, the optical element is a total internal reflector optical element.

[0034] In embodiments, the carrier may be a printed circuit board. In embodiments, the at least one first light emitting diodes, N-LEDs, may comprises a plurality of N-LEDs e.g. 2, 3, 4, 5, 6, 7, 8, 9 or 10 N-LEDs.

[0035] In embodiments, the plurality of second light emitting diodes, M-LEDs, may comprises at least 20 M-LEDs, preferably at least 30 M-LEDs, more preferably at least 40 M-LEDs, most preferably at least 50 M-LEDs.

[0036] In an embodiment, the green-yellow phosphor comprises a phosphor of the type AsBsOn Ce, wherein A in embodiments comprises one or more of Y, La, Gd, Tb and Lu, especially (at least) one or more of Y, Gd, Tb and Lu, and wherein B in embodiments comprises one or more of Al, Ga, In and Sc. Especially, A may comprise one or more of Y, Gd and Lu, such as especially one or more of Y and Lu. Especially, B may comprise one or more of Al and Ga, more especially at least Al, such as essentially entirely Al. Hence, especially suitable luminescent materials are cerium comprising garnet materials. Such phosphors may also be referred to as “YAG” (A=Y and B=A1), or “LuAG” (A=Lu and B=A1) or “(Lu,Y)AG” (A= Y and Lu, B=A1). Embodiments of garnets especially include A3B5O12 garnets, wherein A comprises at least yttrium or lutetium and wherein B comprises at least aluminum. Such garnets may be doped with cerium (Ce), with praseodymium (Pr) or a combination of cerium and praseodymium; especially however with Ce. Especially, B may comprise aluminum (Al); however, in addition to aluminum, B may also partly comprise gallium (Ga) and / or scandium (Sc) and / or indium (In), especially up to about 20% of B, more especially up to about 10 % of B (i.e. the B ions essentially consist of 90 or more mole % of Al and 10 or less mole % of one or more of Ga, Sc and In); B may especially comprise up to about 10% gallium. In another variant, B and O may at least partly be replaced by Si and N. The element A may especially be selected from the group consisting of yttrium (Y), gadolinium (Gd), terbium (Tb) and lutetium (Lu). Further, Gd and / or Tb are especially only present up to an amount of about 20% of A. In a specific embodiment, the garnet luminescent material comprises (Yi-xLux)3B50i2:Ce, wherein x is equal to or larger than 0 and equal to or smaller than 1. The term “:Ce”, indicates that part of the metal ions (i.e. in the garnets: part of the “A” ions) in the luminescent material is replaced by Ce. For instance, in the case of (Yi-xLux)3A150i2:Ce, part of Y and / or Lu is replaced by Ce. This is known to the person skilled in the art. Ce will replace A in general for not more than 10%; in general, the Ce concentration will be in the range of 0.1 to 4%, especially 0.1 to 2% (relative to A). Assuming 1% Ce and 10% Y, the full correct formula could be (Yo.iLuo.sgCeo.o sALOn. Ce in garnets is substantially or only in the trivalent state, as is known to the person skilled in the art. In an embodiment, the orange-red phosphor comprises a phosphor of the type M’XM2-2XAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x may be selected from the range of 0-1, wherein A comprises a tetravalent cation, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine. Such luminescent materials may herein also be indicated as “KSiF” or “KSF”, whether or not M comprises K or one or more other alkaline cations. Herein, M’xM2-2xAX6 doped with tetravalent manganese, may further also shortly be indicated as “phosphor”, i.e. the phrase "phosphor comprising M’xM2-2xAX6 doped with tetravalent manganese" may in an embodiment also be read as M’xM2-2xAX6 doped with tetraval ent manganese phosphor, or (tetraval ent) Mn-doped M’XM2-2XAX6 phosphor, or shortly "phosphor". Relevant alkaline earth cations (M’) are magnesium (Mg), strontium (Sr), calcium (Ca) and barium (Ba), especially one or more of Sr and Ba. Relevant alkaline cations (M) are sodium (Na), potassium (K) and rubidium (Rb). Optionally, also lithium (Li) and / or cesium (Cs) may be applied. In a preferred embodiment, M comprises at least potassium. In yet another embodiment, M comprises at least rubidium. The phrase “wherein M comprises at least potassium” indicates for instance that of all M cations in a mole M’xM2-2xAX6 , a fraction comprises K+and an optionally remaining fraction comprises one or more other monovalent (alkaline) cations (see also below). In another preferred embodiment, M comprises at least potassium and rubidium. Optionally, the M’XM2- 2xAXe luminescent material has the hexagonal phase. In yet another embodiment, the M’XM2- 2xAXe luminescent material has the cubic phase. In an embodiment, a combination of different alkaline cations may be applied. In yet another embodiment, a combination of different alkaline earth cations may be applied. In yet another embodiment, a combination of one or more alkaline cations and one or more alkaline earth cations may be applied. As indicated above, x may be selected from the range of 0-1, especially x < 1. In specific embodiments, x = 0. The term “tetravalent manganese” refers to Mn4+. This is a well-known luminescent ion. In the formula as indicated above, part of the tetravalent cation A (such as Si) is being replaced by manganese. Hence, M’xM2-2xAX6 doped with tetravalent manganese may also be indicated as M’xM2-2xAi-mMnmX6. The mole percentage of manganese, i.e. the percentage it replaces the tetravalent cation A will in general be in the range of 0.1-15 %, especially 1-12 %, i.e. m is in the range of 0.001-0.15, especially in the range of 0.01-0.12. A comprises a tetravalent cation, and preferably at least comprises silicon. A may optionally (further) comprise one or more of titanium (Ti), germanium (Ge), stannum (Sn) and zinc (Zn). Preferably, at least 80%, even more preferably at least 90%, such as at least 95% of M consists of silicon. Hence, in a specific embodiment, M’xM2-2xAX6 may also be described as M’xM2-2xAi-m-t-g-s-zrMnmTitGegSnsZrzrX6, wherein m and x are as indicated above, and wherein t,g,s,zr are each individually preferably in the range of 0-0.2, especially 0-0.1, even more especially 0-0.05, wherein t+g+s+zr is smaller than 1, especially equal to or smaller than 0.2, preferably in the range of 0-0.2, especially 0-0.1, even more especially 0-0.05, and wherein A is especially Si. X is preferably fluorine (F). As indicated above, M relates to monovalent cations, but preferably at least comprises potassium and / or rubidium. Other monovalent cations that may further be comprised by M can be selected from the group consisting of lithium (Li), sodium (Na), cesium (Cs) and ammonium (NHL). In an embodiment, preferably at least 80%(i.e. 80% of all moles of the type M), even more preferably at least 90%, such as 95% of M consists of potassium and / or rubidium. Especially, in these embodiments, x is thus zero. As indicated above, X relates to a monovalent anion, but at least comprises fluorine. Other monovalent anions that may optionally be present may be selected from the group consisting of chlorine (Cl), bromine (Br), and iodine (I). Preferably, at least 80%, even more preferably at least 90%, such as 95% of X consists of fluorine. Hence, in a specific embodiment, M’xM2-2xAX6 can also be described as M’XM2- 2xA(Fi-ci-b-iClciBrbIi)6, wherein cl,b,i are each individually preferably in the range of 0-0.2, especially 0-0.1, even more especially 0-0.05, and wherein cl+b+i is smaller than 1, especially equal to or smaller than 0.2, preferably in the range of 0-0.2, especially 0-0.1, even more especially 0-0.05. Especially, X essentially consists of F (fluorine). In an embodiment, M’XM2-2XAX6 comprises BGSiFe. As manganese replaces part of a host lattice ion and has a specific function, it is also indicated as “dopant” or “activator”. Hence, the hexafluorosilicate is doped or activated with manganese (Mn4+). Here below, M’xM2-2xAX6 is also indicated as M’XM”2-2XAX6.

[0037] In an embodiment, the orange-red phosphor comprises a phosphor of the nitride or oxynitride class, comprising I ESisNs Eu2, or MAlSiNvEu2or Ca2AlSi3O2Ns:Eu2+, etc., wherein M comprises one or more of Ba, Sr, and Ca, especially in embodiments at least Sr. Hence, in embodiments, the luminescent may comprise one or more materials selected from the group consisting of (Ba,Sr,Ca)S:Eu, (Ba,Sr,Ca)AlSiN3:Eu and (Ba,Sr,Ca)2SisN8:Eu. In these compounds, europium (Eu) is substantially or only divalent, and replaces one or more of the indicated divalent cations. In general, Eu will not be present in amounts larger than 10% of the cation; its presence will especially be in the range of about 0.5 to 10%, more especially in the range of about 0.5 to 5% relative to the cation(s) it replaces. The term “:Eu”, indicates that part of the metal ions is replaced by Eu (in these examples by Eu2+). For instance, assuming 2% Eu in CaAlSi Eu, the correct formula could be (Cao.98Euo.o2)AlSiN3. Divalent europium will in general replace divalent cations, such as the above divalent alkaline earth cations, especially Ca, Sr, or Ba. The material (Ba,Sr,Ca)S:Eu can also be indicated as MS:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound calcium or strontium, or calcium and strontium, more especially calcium. Here, Eu is introduced and replaces at least part of M (i.e. one or more of Ba, Sr, and Ca). Further, the material (Ba,Sr,Ca)2SisN8:Eu can also be indicated as NfcSis Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound Sr and / or Ba. In a further specific embodiment, M consists of Sr and / or Ba (not taking into account the presence of Eu), especially 50 to 100%, more especially 50 to 90% Ba and 50 to 0%, especially 50 to 10% Sr, such as Bai.sSro.sSisNsHu (i.e. 75 % Ba; 25% Sr). Here, Eu is introduced and replaces at least part of M, i.e. one or more of Ba, Sr, and Ca). Likewise, the material (Ba,Sr,Ca)AlSiN3:Eu can also be indicated as MAlSi Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound calcium or strontium, or calcium and strontium, more especially calcium. Here, Eu is introduced and replaces at least part of M (i.e. one or more of Ba, Sr, and Ca). Eu in the above indicated luminescent materials is substantially or only in the divalent state, as is known to the person skilled in the art.

[0038] In a further aspect, there is provided a LED package comprising a package housing that houses a lighting device as summarized above. The LED package housing may have a high reflectivity of at least 80%. In yet a further aspect, there is provided a lamp or a luminaire comprising a lighting device as summarized above or a LED package as summarized above. Optionally, such a lamp or luminaire may comprise a controller for individually controlling the first and second white LED light sources.

[0039] BRIEF DESCRIPTION OF THE DRAWINGS

[0040] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention.

[0041] Figure 1 schematically illustrates a top view of a lighting device, Figure 2 schematically illustrates a cross-sectional view of a LED covered by an optical element,

[0042] Figure 3 schematically illustrates a top view of a lighting device, Figure 4 schematically illustrates a LED package, and

[0043] Figures 5a and 5b schematically illustrate a respective lamp or a luminaire.

[0044] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] As illustrated in figure 1, a lighting device 100 configured to provide device light comprises a carrier 151. A first white LED light source 11 is arranged on the carrier 151 and configured to provide first white LED light source light. A second white LED light source 12 is arranged on the carrier 151 and configured to provide second white LED light source light. The first white LED light source 11 comprises at least one first light emitting diodes, N-LEDs, 101. In embodiments, the plurality of N-LEDs may comprise 2, 3, 4, 5, 6, 7, 8, 9 or 10 N-LEDs. In embodiments, the plurality of M-LEDs may comprise at least 20 M-LEDs, preferably at least 25 M-LEDs, more preferably at least 30 M-LEDs, most preferably at least 35 M-LEDs.

[0046] Each of the N-LEDs 101 comprises a die having a first surface area, SAI, wherein the SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers. In embodiments, SAI may have a largest spatial extent, SEI, that is greater than or equal to 400 micrometers, preferably >=500 micrometers, more preferably >=600 micrometers, most preferably >=700 micrometers.

[0047] The second white LED light source 12 comprises a plurality of second light emitting diodes, M-LEDs, 102. Each of the M-LEDs 102 comprises a die having a second surface area, SA2, wherein the SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers. In embodiments, SA2 may have a largest spatial extent, SE2, that is less than or equal to 80 micrometers, preferably <=70 micrometers, more preferably <=60 micrometers, most preferably <=50 micrometers.

[0048] A ratio, Rl, defined by SA1 / SA2 is equal to or larger than 10. In embodiments, SA1 / SA2 may be equal to or larger than 15, preferably >=20, more preferably >=25, most preferably >=30.

[0049] The plurality of M-LEDs 102 are arranged in a group of M-LEDs and confined within an area, A, 112. The plurality of N-LEDs 101 are arranged outside the area, A, 112. The plurality of M-LEDs 102 comprise a plurality of red M-LEDs providing red M- LED light, a plurality of green M-LEDs providing green M-LED light, and a plurality of blue M-LEDs providing blue M-LED light. The second LED light source light comprises said red M-LED light, said green M-LED light and said blue M-LED light. The second white LED light source light is white light having a second correlated color temperature, CCT2, in a range from 1700 K to 6500 K, preferably 2700 K to 6500 K, more preferably 2700 K to 4500 K, and a color render index, CRI2, of at least 80.

[0050] The M-LEDs 102 in the group of M-LEDs 102 are arranged at a pitch Pl and the first and second white LED light sources 11, 12 are arranged at a pitch P2, wherein P2>5P1.

[0051] Each of the at least one N-LEDs 101 may comprise a white phosphorconverted LED comprising a blue LED and a converter comprising a green-yellow phosphor configured to at least partly convert blue light emitted by said blue LED into green-yellow converted light and an orange-red phosphor configured to at least partly convert the blue light emitted by said blue LED and / or at least partly convert said green-yellow converted light into orange-red converted light. Alternatively, each of the at least one N-LEDs 101 may comprise at least one red N-LED configured to provide red N-LED light, at least one green N-LED configured to provide green N-LED light and at least one further blue N-LED configured to provide blue N-LED light. The first LED light source light may be white light having a first correlated color temperature, CCT1, in a range from 1700K to 6500K and a color render index, CRI1, of at least 80 and, optionally, CCT2>CCT1. Each of the at least one further blue N-LED and each of the at least one red N-LED may be direct-emitting LEDs. Each of the at least one green N-LED comprises a blue LED and a converter comprising a further greenyellow phosphor configured to at least partly convert further blue N-LED light emitted by said further blue N-LED into further green-yellow converted light.

[0052] In embodiments, the green phosphor may comprise LuAG phosphor. In embodiments, the green-yellow phosphor may comprise YAG, LuAG, and / or (Lu,Y)AG phosphor. In embodiments, the orange-red phosphor may comprise oxynitride, nitride, and / or KSF phosphor. In embodiments, the converter may comprise a polymer matrix e.g. silicone such as Polydimethylsiloxane (PDMS). For example, the phosphor may be phosphor particles which may be dispersed in the polymer matrix.

[0053] The number of M-LEDs 102 may be defined as X and the number of N-LEDs 101 may be defined as Y, and X may be greater than or equal to 5 times Y. This is exemplified in figure 1 in that the number of M-LEDs 102 is 16, the number of N-LEDs 101 is 3, whereby the ratio 16 to 3 is greater than 5.

[0054] For example, the lighting device may comprise only one red N-LED, only one blue N-LED and only one green N-LED. Defining TSAI as total surface area of all N-LEDs 101, i.e. sum of all SAI, and defining TSA2 as a total surface area of all M-LEDs 102, a ratio, R2, defined by TSA1 / TSA2 is then equal or greater than 2.

[0055] Figure 2, illustrates schematically, using a side / cross-sectional view, embodiments wherein the plurality of second light emitting diodes, M-LEDs 102 are covered by an optical element 120 configured to collimate the second white LED light source light. The optical element 120 is preferably a total internal reflector optical element.

[0056] As illustrated in figure 3, the carrier 151 may be a printed circuit board (PCB) comprising circuits 131 configured to provide electric connections between the M-LEDs 102 and a driver 130, and configured to provide electric connections between the N-LEDs 101 and the driver 130.

[0057] As illustrated in figure 4, and with continued reference to figures 1 to 3, a LED package 200 may comprise a package housing 201 that houses a lighting device 100 as described herein.

[0058] As illustrated in figure 5a, and with continued reference to figures 1 to 3, a lamp or a luminaire 300 may comprise a lighting device 100 as described herein and optionally comprise a controller 140 for individually controlling the first and second white LED light sources 11, 12. As illustrated in figure 5b, and with continued reference to figures 1 to 3, a lamp or a luminaire 300 may comprise a LED package 200 as described herein and optionally comprise a controller 140 for individually controlling the first and second white LED light sources 11, 12.

Claims

CLAIMS1. A lighting device (100) configured to provide device light, comprising: a carrier (151); a first white LED light source (11) arranged on said carrier (151) and configured to provide first white LED light source light; a second white LED light source (12) arranged on said carrier (151) and configured to provide second white LED light source light; wherein the first white LED light source (11) comprises at least one first light emitting diode, N-LEDs, (101) each of the N-LEDs (101) comprising a die having a first surface area, SAI, wherein the SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers; wherein the second white LED light source (12) comprises a plurality of second light emitting diodes, M-LEDs, (102) each of the M-LEDs (102) comprising a die having a second surface area, SA2, wherein the SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers; wherein a ratio, Rl, defined by SA1 / SA2 is equal to or larger than 10; wherein the plurality of M-LEDs (102) are arranged in a group of M-LEDs and confined within an area, A, (112), wherein the plurality of N-LEDs (101) are arranged outside the area, A, (112), wherein the plurality of M-LEDs (102) comprise a plurality of red M-LEDs providing red M-LED light, a plurality of green M-LEDs providing green M-LED light, and a plurality of blue M-LEDs providing blue M-LED light; wherein the second LED light source light comprises said red M-LED light, said green M-LED light and said blue M-LED light; and wherein the second white LED light source light is white light having a second correlated color temperature, CCT2, in a range from 1700K to 6500K and, optionally, a color render index, CRI2, of at least 80.

2. The lighting device (100) according to claim 1, wherein: the M-LEDs (102) in the group of M-LEDs (102) are arranged at a pitch Pl,and the first and second white LED light sources (11, 12) are arranged at a pitch P2, wherein P2>5P1.

3. The lighting device (100) according to any one of claims 1 to 2, wherein: each of the at least one N-LEDs (101) comprise a white phosphor-convertedLED comprising a blue LED and a converter comprising a green-yellow phosphor configured to at least partly convert blue light emitted by said blue LED into green-yellow converted light and an orange-red phosphor configured to at least partly convert the blue light emitted by said blue LED and / or at least partly convert said green-yellow converted light into orange- red converted light.

4. The lighting device (100) according to any one of claims 1 to 2, wherein: the plurality of N-LEDs (101) comprise at least one red N-LED configured to provide red N-LED light, at least one green N-LED configured to provide green N-LED light and at least one further blue N-LED configured to provide blue N-LED light.

5. The lighting device (100) according to claim 3 or 4, wherein: the first LED light source light is white light having a first correlated color temperature, CCT1, in a range from 1700K to 6500K and, optionally, a color render index, CRI1, of at least 80.

6. The lighting device (100) according to claim 5, wherein: CCT2>CCTl+500K.

7. The lighting device (100) according to any one of claims 4 to 6, wherein: each of the at least one further blue N-LED and each of the at least one red N-LED are direct-emitting LEDs.

8. The lighting device (100) according to any one of claims 4 to 7, wherein: each of the at least one green N-LED comprises a blue LED and a converter comprising a further green-yellow phosphor configured to at least partly convert further blue N-LED light emitted by said further blue N-LED into further green-yellow converted light.

9. The lighting device (100) according to any one of the preceding claims, wherein: the number of M-LEDs (102) is X; the number of N-LEDs (101) is Y; and wherein X is greater than or equal to 5 times Y.

10. The lighting device (100) according to according to claim 9, comprising only one red N-LED, only one blue N-LED and only one green N-LED.

11. The lighting device (100) according to any one of claims 1 to 9, wherein:TSAI is defined as total surface area of all N-LEDs (101) and TSA2 is defined as a total surface area of all M-LEDs (102), and a ratio, R2, defined by TSA1 / TSA2 is equal or greater than 2.

12. The lighting device (100) according to according to any one of the preceding claims, wherein: the carrier (151) is a printed circuit board, PCB, comprising circuits (131) configured to provide electric connections between the M-LEDs (102) and a driver (130), and configured to provide electric connections between the N-LEDs (101) and the driver (130).

13. The lighting device (100) according to according to any one of the preceding claims, wherein: the plurality of second light emitting diodes, M-LEDs (102) are covered by an optical element (120) configured to collimate the second white LED light source light, preferably a total internal reflector optical element.

14. A LED package (200) comprising a package housing (201) that houses a lighting device (100) according to any one of the preceding claims.

15. A lamp or a luminaire (300) comprising a lighting device (100) according to any one of claims 1 to 13 or a LED package (200) according to claim 14, and optionally comprising a controller (140) for individually controlling the first and second white LED light sources (11, 12).

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