A light generating system generating white light

Abstract

The invention provides a light generating system (1000) comprising a first solid state light source (10) and a luminescent converter (2000), wherein: (A) the first solid state light source (10) is configured to generate first light source light (11) having a first peak wavelength (λpi ) selected from the range of 490-520 nm; (B) the luminescent converter (2000) is configured in a light receiving relationship with the first solid state light source (10); wherein the luminescent converter (2000) comprises a first luminescent material (210); wherein the first luminescent material (210) comprises a luminescent material of the type M'XM2-2XAX6 doped with tetravalent manganese, wherein M' comprises an alkaline earth cation, M comprises an alkaline cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, at least comprising fluorine; wherein the first luminescent material (210) is configured to convert part of the first light source light (11) received by the first luminescent material (210) into first luminescent material light (211); wherein the first luminescent material light (211) has a first centroid wavelength (λci) selected from the range of 610-650 nm; wherein the first luminescent material light (211) comprises at least one emission band having a first full width at half maximum FWHM1 of ≤ 55 nm; and (C) the light generating system (1000) is configured to generate system light (1001) comprising the first luminescent material light (211) and at least part of the first light source light (11); wherein the system light (1001) is white light having a correlated color temperature selected from the range of 1500-3400 K.

Description

[0001]2024PF80190 1 A light generating system generating white light FIELD OF THE INVENTION The invention relates to a light generating system. The invention further relates to a lighting device comprising such light generating system. BACKGROUND OF THE INVENTION Light generating systems are known in the art. For instance, US2019067532A1 describes a light emitting device which emits a secondary light with high color purity and has a fast response speed. A KSF phosphor which absorbs a part of blue light and emits red light and a CASN phosphor are distributed in a resin which seals an LED chip which emits the blue light. The KSF phosphor absorbs the blue light and emits the red light by forbidden transition, and the CASN phosphor absorbs the blue light and emits the red light by allowed transition. SUMMARY OF THE INVENTION Conventional light generating systems (e.g. incandescent or fluorescent lamps) are rapidly being replaced by light emitting diode (LED) based lighting solutions. LED-based lighting solutions may generally comprise a blue-emitting light source and a luminescent converter, wherein the luminescent converter may comprise multiple types of phosphors, such as a yellow and a red phosphor, to produce especially white light with a suitable color temperature. For e.g. cleanroom lighting, blue-free LED lighting may be desired. To produce blue-free LED light, a luminescent converter comprising e.g. a high concentration of phosphor or a light filter may be used. However, prior art solutions may have problems to provide a reliable solution, as phosphors may be unevenly distributed, or may degrade over time, allowing blue light to be emitted. Further, prior art solutions may have problems to provide an efficient solutions, as a light filter may reduce the lumen output of the LED-based lighting, and a high concentration of phosphor may increase light (back)scattering. Hence, it is an aspect of the invention to provide an alternative light generating system, which preferably further at least partly obviates one or more of above-described drawbacks. The 2024PF80190 2 present invention may have as object to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. According to a first aspect, the invention provides a light generating system comprising a first solid state light source and a luminescent converter. In embodiments, the light generating system may consist of the first solid state light source and the luminescent converter. The first solid state light source may be configured to generate first light source light having a first peak wavelength (λp1) selected from the range of 490-520 nm, such as selected from the range of 500-520nm. Further, the luminescent converter may be configured in a light receiving relationship with the first solid state light source. Especially, the luminescent converter may comprise a first luminescent material. The first luminescent material may be configured to convert part of the first light source light received by the first luminescent material into first luminescent material light. The first luminescent material light may have a first centroid wavelength (λc1) selected from the range of 610-650 nm. Further, the first luminescent material light may comprise at least one emission band having a first full width at half maximum FWHM1of ≤ 55 nm. In embodiments, the light generating system may be configured to generate system light comprising the first luminescent material light and at least part of the first light source light. Especially, the system light may be white light having a correlated color temperature selected from the range of 1500-3400 K. Hence, in specific embodiments, the invention provides a light generating system comprising a first solid state light source and a luminescent converter, wherein: (A) the first solid state light source is configured to generate first light source light having a first peak wavelength (λp1) selected from the range of 490-520 nm; (B) the luminescent converter is configured in a light receiving relationship with the first solid state light source; wherein the luminescent converter comprises a first luminescent material; wherein the first luminescent material is configured to convert part of the first light source light received by the first luminescent material into first luminescent material light; wherein the first luminescent material light has a first centroid wavelength (λc1) selected from the range of 610-650 nm; wherein the first luminescent material light comprises at least one emission band having a first full width at half maximum FWHM1 of ≤ 55 nm; and (C) the light generating system is configured to generate system light comprising the first luminescent material light and at least part of the first light source light; wherein the system light is white light having a correlated color temperature selected from the range of 1500-3400 K. Such a light generating system may especially provide system light free from blue (first light source) light. Especially, such a light generating system may provide white 2024PF80190 3 system light, wherein the system light may be free from blue light even upon damage to the luminescent converter and / or degradation of the first luminescent material. Hence, such a light generating system may be reliable. Further, such a light generating system may be relatively efficient, as no light filter is needed to remove blue light from the system light. In embodiments, the light generating system may comprise a first solid state light source. The first solid state light source may especially be selected from the group comprising a light emitting diode (LED), a laser diode, a superluminescent diode, and a multi-junction light emitting diode, though other options may also be possible (see below). The first solid state light source may be configured to generate first light source light. The first light source light may have a first peak wavelength (λp1) selected from the range of 490- 530 nm, like from the range of 500-520 nm, such as from the range of 500-515 nm, especially from the range of 500-510 nm. Alternatively, the first light source light may have a first peak wavelength (λp1) selected from the range of 490-530 nm, like from the range of 500-520 nm, such as from the range of 505-520 nm, especially from the range of 510-520 nm. Hence, the first light source light may be green light. The terms “green light” or “green emission”, and similar terms, may especially relate to light having a wavelength in the range of about 490-560 nm. The term “peak wavelength” may refer to the wavelength where the radiometric emission spectrum of the light source reaches its maximum, i.e., the peak wavelength may denote the wavelength at which the largest (emission intensity) value is found in a graph of the spectral power distribution. The peak wavelength may especially be determined at room temperature. The first light source light may have a first spectral power distribution. Especially, the first light source light may have a first spectral power distribution, wherein ≥ 80%, such as ≥ 90%, especially ≥ 95%, including (essentially) 100%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 490-530 nm, such as especially in the wavelength range of 500-520 nm. Further, the first light source light may have a first spectral power distribution, wherein ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, the first light source light may have a first spectral power distribution, wherein ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of ≤ 490 nm, such as in the wavelength range of 380-489 nm. Hence, the first light source light may be (essentially) free from blue light. The term “blue light”, and 2024PF80190 4 similar terms, may especially relate to light having a wavelength in the range of about 440- 490 nm. The light generating system may further comprise a luminescent converter. The luminescent converter may comprise one or more luminescent materials, such as especially at least a first luminescent material. The term “luminescent material” may especially refer to a material that can convert first radiation, especially one or more of UV radiation, blue radiation, and green radiation, into second radiation. Herein, UV (ultraviolet) may refer to a wavelength selected from the range of 190-380 nm, such as 200-380 nm, though other wavelengths may also be possible. In general, the first radiation and second radiation may have different spectral power distributions, with the second radiation generally having a spectral power distribution at larger wavelengths than the first radiation (i.e. “down- conversion”). In embodiments, the “luminescent material” may especially refer to a material that can convert radiation into e.g. visible and / or infrared light. The terms “visible light” or “visible emission”, and similar terms, refer to light having one or more wavelengths in the range of about 380-780 nm. Further, IR (infrared) may especially refer to radiation having a wavelength selected from the range of 780-3000 nm, such as 780-2000 nm, e.g. a wavelength of ≤ 1500 nm, like a wavelength of ≥ 900 nm, though other wavelengths may also be possible. For instance, in embodiments the luminescent material may be able to convert one or more of UV radiation, blue radiation, and green radiation, into visible light. Hence, upon excitation with radiation, the luminescent material may emit radiation. In general, the luminescent material will be a down converter, i.e. radiation with a smaller wavelength is converted into radiation with a larger wavelength (λex<λem). In embodiments, the term “luminescence” may refer to phosphorescence. In embodiments, the term “luminescence” may also refer to fluorescence. Instead of the term “luminescence”, also the term “luminescent material light” or “emission” may be applied. Hence, the terms “first radiation” and “second radiation” may refer to excitation radiation and emission (radiation), respectively. Likewise, the term “luminescent material” may in embodiments refer to phosphorescence and / or fluorescence. The term “luminescent material” may also refer to a plurality of different luminescent materials. Examples of possible luminescent materials are indicated below. Hence, the term “luminescent material” may in specific embodiments also refer to a luminescent material composition. Instead of the term “luminescent material” also the term “phosphor” may be applied. These terms are known to the person skilled in the art. 2024PF80190 5 In embodiments, luminescent materials may be selected from garnets and nitrides, especially doped with trivalent cerium or divalent europium, respectively. The term “nitride” may also refer to oxynitride or nitridosilicate, etc. Alternatively or additionally, the luminescent material(s) may be selected from silicates, especially doped with divalent europium. In embodiments, the luminescent material may comprise a divalent europium comprising oxynitride luminescent material. Further, in embodiments, the luminescent material may comprise a divalent europium comprising nitride luminescent material. In embodiments, the luminescent material may comprise a luminescent material of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc; and wherein the light source light may comprise blue light source light. 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. Embodiments of garnets especially include A3B5O12garnets, wherein A comprises at least yttrium (Y) or lutetium (Lu) and wherein B comprises at least aluminum (Al). 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), with optionally gallium (Ga) and / or scandium (Sc) and / or indium (In) up to about 20% of B, more especially up to about 10 % of B (i.e. the B ions essentially consist of ≥ 90 mole % of Al and ≤ 10 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 (Y1-xLux)3B5O12:Ce, wherein 0 ≤ x ≤ 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. 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). Ce in garnets is substantially or only in the trivalent state, as is known to the person skilled in the art. In embodiments, such luminescent materials may have a suitable spectral distribution, have a relatively high efficiency, and have a relatively high thermal stability. In specific embodiments, the luminescent material may comprise (Yx1A’x2Cex3)3(Aly1B’y2)5O12. Here, A’ comprises one or more elements selected from the 2024PF80190 6 group consisting of lanthanides, and B’ comprises one or more elements selected from the group of Ga, In and Sc, wherein x1+x2+x3=1, wherein x3>0, wherein 0<x2+x3≤0.2, wherein y1+y2=1, wherein 0≤y2≤0.2. Especially, x3 is selected from the range of 0.001-0.1. Note that in embodiments x2=0. Alternatively or additionally, in embodiments y2=0. In embodiments, the luminescent material may comprise a luminescent material of the type A3Si6N11:Ce3+, wherein A comprises one or more of Y, La, Gd, Tb and Lu, such as in embodiments one or more of La and Y. In embodiments, the luminescent material may alternatively or additionally comprise one or more of MS:Eu2+and / or M2Si5N8:Eu2+and / or MAlSiN3:Eu2+and / or Ca2AlSi3O2N5:Eu2+, etc., wherein M comprises one or more of Ba, Sr and Ca, especially in embodiments at least Sr. Hence, in embodiments, the luminescent material 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)2Si5N8:Eu. In these compounds, europium (Eu) is substantially or only divalent, and replaces one or more of the indicated divalent cations, as is known to the person skilled in the art. 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 (indicated by M) is replaced by Eu (in these examples by Eu2+). For instance, assuming 2% Eu in CaAlSiN3:Eu, the correct formula could be (Ca0.98Eu0.02)AlSiN3. The term “luminescent material” herein especially relates to inorganic luminescent materials. Alternatively or additionally, also other luminescent materials may be applied. For instance quantum dots and / or organic dyes may be applied and may optionally be embedded in transmissive matrices like e.g. polymers, like PMMA, or polysiloxanes, etc.. In embodiments, the luminescent material may comprise a luminescent material of the type M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux. Herein, M may comprise one or more of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba), such as especially one or more of Ca, Sr, and Ba. Hence, M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux may especially refer to (Mg,Ca,Sr,Ba)1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux. Such a luminescent material may be indicated as an SLA-type phosphor, or SLA phosphor. Luminescent materials of the type M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Euxmay be described in US2021171827A1, which is hereby herein incorporated by reference. In M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux, x may be selected from the range of 0 < x ≤ 0.1, such as from the range of 0.0005 < x ≤ 0.08, especially from the range of 0.001 < x ≤ 0.05. Hence, europium (Eu) may not replace more than 10% of the cation M, and may substantially or only be in the divalent state (Eu2+), as is known to the 2024PF80190 7 person skilled in the art. Further, in M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux, y may be selected from the range of 0 ≤ y ≤ 1, such as from the range of 0 ≤ y ≤ 0.75, especially from the range of 0 ≤ y ≤ 0.6. In specific embodiments, y = 0. In M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux, z may be selected from the range of 0 ≤ z ≤ 0.1, such as from the range of 0 ≤ z ≤ 0.07, especially from the range of 0 ≤ z ≤ 0.05. Hence, in embodiments, in an SLA phosphor, SiN may replace AlO to a maximum of 10 mole%. In embodiments, an SLA phosphor may crystallize in a UCr4C4type crystal structure. Hence, the luminescent material may comprise a luminescent material of the type M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux, wherein M comprises one or more of Ca, Sr, and Ba, wherein 0 < x ≤ 0.04, wherein 0 ≤ y ≤ 1, wherein 0 ≤ z ≤ 0.05, and wherein y + z ≤ 1. Further, the luminescent material may comprise a SiAlON phosphor, such as selected from the group comprising (a) Si12–m–nAlm+nOnN16–n:Eu2+(α-SiAlON), (b) Si6–nAlnOnN8–n:Eu2+, wherein 0 ≤ n ≤ 4.2 (β-SiAlON), and (c) Si2–nAlnO1+nN2–n:Eu2+, wherein 0 ≤ n ≤ 0.2 (O-SiAlON). In embodiments, the luminescent material may comprise a tetravalent manganese-comprising luminescent material, i.e., a luminescent material doped with tetravalent manganese. Especially, in embodiments, the luminescent material may comprise a luminescent material 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, and 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. A luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese is amongst others described in WO2013121355A1, which is herein incorporated by reference. Passages from WO2013121355A1 are also copied herein. In embodiments, the alkaline earth cation M’ may comprise one or more of magnesium (Mg), strontium (Sr), calcium (Ca) and barium (Ba), especially one or more of Sr and Ba. Further, the alkaline cations M may comprise one or more of sodium (Na), potassium (K) and rubidium (Rb). Optionally, M may (further) comprise one or more of ammonium (NH4+), lithium (Li), and cesium (Cs). 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 2024PF80190 8 below). In another preferred embodiment, M comprises at least potassium and rubidium. Optionally, the M’xM2-2xAX6 luminescent material has the hexagonal phase. In yet another embodiment, the M’xM2-2xAX6luminescent material has the cubic phase. In an embodiment, a combination of different alkaline cations M may be applied. In yet another embodiment, a combination of different alkaline earth cations M’ may be applied. In yet another embodiment, a combination of one or more alkaline cations M and one or more alkaline earth cations M’ may be applied. For instance, KRb0.5Sr0.25AX6might be applied. As indicated above, x in the formula M’xM2-2xAX6 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’xM2-2xA1-mMnmX6(or M’xM2-2xAX6:Eu). 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. 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+). In embodiments, A may comprise 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 A consists of silicon. In a specific embodiment, M’xM2-2xAX6 can also be described as (K1-r-l-n-c-nh RbrLilNanCsc(NH4)nh)2AX6, wherein r is in the range of 0-1, wherein l,n,c,nh are each individually preferably in the range of 0-1, preferably in the range of 0-0.2, especially in the range of 0-0.1, even more especially in the range of 0- 0.05, and wherein r+l+n+c+nh is in the range of 0-1, especially l+n+c+nh < 1, especially ≤ 0.2, preferably in the range of 0-0.2, especially in the range of 0-0.1, even more especially in the range of 0-0.05. X is preferably fluorine (F). Further, in a specific embodiment, M’xM2-2xAX6 can also be described as MgmgCacaSrsrBaba(KkRbrLilNanCsc(NH4)nh)2AX6, with k, r, l, n, c, nh each individually being in the range of 0-1, wherein mg, ca, sr, ba are each individually in the range of 0-1, and wherein mg+ca+sr+ba+k+r+l+n+c+nh=1. In embodiments, k=1, and the others (mg, ca, sr, ba, r, l, n, c, nh) are 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 2024PF80190 9 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’xM2-2xAX6can also be described as M’xM2-2xA(F1-cl-b-iClclBrbIi)6, wherein cl,b,i are each individually preferably in the range of 0-0.2, especially in the range of 0-0.1, even more especially in the range of 0-0.05, and wherein cl+b+i < 1, especially ≤ 0.2, preferably in the range of 0-0.2, especially in the range of 0-0.1, even more especially in the range of 0-0.05. Hence, M’xM2-2xAX6can also be described as (K1-r-l-n-c-nhRbrLilNanCsc(NH4)nh)2Si1-m-t-g-s-zrMnmTitGegSnsZrzr(F1-cl-b-iClclBrbIi)6, with the values for r,l,n,c,nh,m,t,g,s,zr,cl,b,i as indicated above. In an embodiment, M’xM2-2xAX6 comprises K2SiF6 (indicated herein also as KSiF system). In another preferred embodiment, M’xM2-2xAX6comprises KRbSiF6(herein also indicated as K,Rb system). In specific embodiments, the indication M’xM2-2xAX6 may refer to one or more of (K,Rb)2SiF6:Mn4+, (K,Rb)2TiF6:Mn4+, K2(Si,Ti)F6:Mn4+, and Rb2(Si,Ti)F6:Mn4+, such as one or more of K2TiF6:Mn4+, of K2SiF6:Mn4+, and of Rb2SiF6:Mn4+. As can be derived from the above, “(Si,Ti)” may indicate one or more of Si and Ti. Hence, in specific embodiments, the luminescent material may comprise one or more of (K,Rb)2SiF6:Mn4+and K2(Si,Ti)F6:Mn4+. The luminescent material may also be coated, as also described in WO2013121355A1. Hence, when M (or A) in chemical formulas refer to n different elements, this may imply that the relevant formula may comprise for the M (or A) position in the formula essentially any permutation of the n different elements. For instance, when M=Ba,Sr,Ca or when M comprises one or more of Ba,Sr,Ca or when M refers to Ba,Sr,Ca, i.e. n=3, this may imply that in the formula Ba, Sr, Ca, (BaxSry), (BaxCay), (CaxSry), or (BaxSryCaz), may be available, wherein in general x+y+z=1. Referring to e.g. M’xM2-2xAX6, this may refer to e.g. one or more of K2SiF6:Mn4+and of Rb2SiF6:Mn4+, or (KxRby)2SiF6:Mn4+, etc. Referring to (Ba,Sr,Ca)AlSiN3:Eu, this may imply BaAlSiN3:Eu, SrAlSiN3:Eu, CaAlSiN3:Eu, (BaxSry)AlSiN3:Eu, (BaxCay)AlSiN3:Eu, (CaxSry)AlSiN3:Eu, or (BaxSryCaz)AlSiN3:Eu. Referring to e.g. A3B5O12:Ce, wherein A in embodiments comprises one or more of Y, La, Gd, Tb and Lu, this may imply Y3B5O12:Ce, La3B5O12:Ce, GdB5O12:Ce, Tb3B5O12:Ce, Lu3B5O12:Ce, but also e.g. (Yx,Gdy)3B5O12:Ce, (Yx,Luy)3B5O12:Ce, (Gdx,Luy)3B5O12:Ce, (Yx,Gdy,Luz)3B5O12:Ce, etc. etc., with hereby only limiting for the sake of economy to unary, binary, and ternary examples, though quaternary and higher examples are not excluded herein. 2024PF80190 10 Further, indications like “K,Rb” or Ba,Sr,Ca, and similar indications (see also above), may indicate one or more of such elements. Hence, (K,Rb)2SiF6:Mn4+, may e.g. refer to K2SiF6:Mn4+and of Rb2SiF6:Mn4+, or (KxRby)2SiF6:Mn4+. Also herein in general x+y=1. Hence, when M (or A) may refer to n different elements, with n being at least two, 2n-1 permutations may in principle be possible. In embodiments, the first luminescent converter may (at least) comprise a first luminescent material. The first luminescent material may comprise any (combination) of the luminescent materials indicated above. The first luminescent material may comprise a quantum structure, such as a quantum dot, or such as a quantum rod. Quantum structures may for instance comprise (such as be based on) one or more of cadmium (Cd), indium (In), zinc (Zn), silver (Ag), and lead (Pb). Further, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, at least comprising fluorine. The first luminescent material may thus comprise a luminescent material of the type M’xM2-2xA(F,Cl,Br,I)6 doped with tetravalent manganese, wherein x may especially be in the range of 0-1. As can be derived from the above, the indication “(F,Cl,Br,I)” may refer to one or more of F, Cl, Br, and I, but may especially refer to at least F, and optionally one or more of Cl, Br, and I (see also above, wherein it is indicated that cl+b+i < 1). Hence, in specific embodiments, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein M’ may comprise an alkaline earth cation, M may comprise an alkaline cation, and x may be in the range of 0-1, wherein A may comprise a tetravalent cation, and wherein X may comprise a monovalent anion, at least comprising fluorine. Such a luminescent material may especially provide luminescent material light in the wavelength range of 610-650, like in the range of 620-640 nm. Further, such a luminescent material may be relatively efficient (in converting first light source light). As indicated above, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein A may comprise a tetravalent cation. Especially, the tetravalent cation A may (at least) comprise one or more of silicon (Si), titanium (Ti), and germanium (Ge). In embodiments, A may (at least) comprise Si. Additionally or alternatively, A may (at least) comprise Ge. Especially, A may (at least) comprise Ti. Hence, in specific embodiments, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein A may comprise titanium. A luminescent material of the type M’xM2-2xAX6:Mn4+(at 2024PF80190 11 least) comprising Ti may have a relatively red-shifted absorption spectrum compared to a luminescent material of the type M’xM2-2xAX6:Mn4+not comprising Ti. Hence, such a luminescent material may have improved absorption at the first peak wavelength (λp1). In embodiments, M in the formula M’xM2-2xAX6:Mn4+may comprise one or more of Na, K, Rb, NH4+, Li, and Cs. Especially, M may comprise one or more of K and Rb. Further, as indicated above, A may comprise one or more of Si, Ge, and Ti. Hence, in embodiments, the first luminescent material may comprise (K,Rb)2(Si,Ge,Ti)F6:Mn4+. The first luminescent material may comprise (Ka,Rbb)2(Six,Gey)F6:Mn4+, wherein a + b = 1, wherein a ≥ 0 and b ≥ 0, wherein x+y = 1, and wherein y > 0, such as y ≥ 0.2, especially y ≥ 0.5, including (essentially) y = 1. Hence, in specific embodiments, the first luminescent material may comprise (Ka,Rbb)2(Six,Gey)F6:Mn4+, wherein a + b = 1, wherein a ≥ 0 and b ≥ 0, wherein x+y = 1, and wherein y > 0. Further, in specific embodiments, the first luminescent material may comprise K2(Six,Gey)F6:Mn4+, wherein x+y = 1, and wherein y > 0 (such as y ≥ 0.2, especially y ≥ 0.5, including (essentially) y = 1). In embodiments, the first luminescent material may comprise K2(Six,Gey)F6:Mn4+, wherein x+y = 1, wherein y > 0, and wherein x > 0. That is, the first luminescent material may at least comprise Ge and Si. Alternatively, the first luminescent material may comprise M’xM2-2xAX6:Mn4+, wherein M may comprise one or more of K and Rb, and wherein A may comprise one or more of Si and Ti. Hence, in specific embodiments, the first luminescent material may comprise (K,Rb)2(Si,Ti)F6:Mn4+. A first luminescent material comprising (at least some) Rb may be more thermally stable and have a higher emission intensity than a first luminescent material without Rb. Yet, a first luminescent material comprising (at least some) Rb may be more difficult to synthesize. Hence, in specific embodiments, the first luminescent material may comprise K2(Si,Ti)F6:Mn4+. Such a first luminescent material may be relatively easy to synthesize. As indicated above, the first luminescent material may comprise one or more of Si and Ti. Especially, in embodiments, the first luminescent material may at least comprise Ti. That is, the first luminescent material may comprise K2(Si1-xTix)F6:Mn4+. In such embodiments, x may be selected from the range of ≥ 0.05, such as from the range of ≥ 0.1, especially from the range of ≥ 0.15. Additionally or alternatively, x may be selected from the range of ≤ 1, such as from the range of ≤ 0.9, especially from the range of ≤ 0.8. Yet, the first luminescent material may comprise more Ti than Si. Hence, x may be selected from the range of ≥ 0.5, such as from the range of ≥ 0.6, especially from the range of ≥ 0.75, like from the range of ≥ 0.9, including (essentially) 1. Hence, in specific embodiments, the first 2024PF80190 12 luminescent material may comprise K2(Si1-xTix)F6:Mn4+, wherein x may be selected from the range of ≥ 0.6. A first luminescent material comprising more Ti than Si as the tetravalent cation may have absorption at larger wavelengths than a first luminescent material comprising more Si than Ti as the tetravalent cation. Hence, a first luminescent material comprising K2(Si1-xTix)F6:Mn4+may have a relatively high absorption for the first light source light, thereby providing the benefit that a concentration of the first luminescent material in the luminescent converter may be reduced. As indicated above, the first luminescent material may comprise a combination of luminescent materials. Hence, in embodiments, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6:Mn4+and a quantum structure. Alternatively, the first luminescent material may (essentially) consist of one or more luminescent materials of the type M’xM2-2xAX6:Mn4+, wherein the one or more luminescent materials of the type M’xM2-2xAX6:Mn4+may differ in one or more of the composition of M and A. For instance, the first luminescent material may comprise a primary first luminescent material of the type (K,Rb)2(Si1-x,Tix)F6:Mn4+, wherein x ≥ 0.6, and a secondary first luminescent material of the type (K,Rb)2(Si1-x,Tix)F6:Mn4+, wherein x ≤ 0.2. Further, the luminescent material may comprise one or more luminescent materials of the type (K,Rb)2(Six,Tiy,Gez)F6:Mn4+, such as especially of the type K2(Six,Tiy,Gez)F6:Mn4+, wherein x, y, and z may be individually selected from the range of 0-1 for each of the one or more luminescent materials. In embodiments, the first luminescent material may be configured to convert part of the first light source light received by the first luminescent material into first luminescent material light. Especially, the first luminescent material may be configured to convert ≥ 5%, such as ≥ 10%, especially ≥ 15%, of (a spectral power of) the first light source light received by the first luminescent material into first luminescent material light. Additionally or alternatively, the first luminescent material may be configured to convert ≤ 30%, such as ≤ 25%, especially ≤ 20%, of (a spectral power of) the first light source light received by the first luminescent material into first luminescent material light. Hence, the luminescent converter, such as especially the first luminescent material, may be configured in a light receiving relationship with the first solid state light source. The first luminescent material light may have a first centroid wavelength (λc1). The term “centroid wavelength”, also indicated as λc, is known in the art, and refers to the wavelength value (in nm) where half of the light energy is at shorter and half the energy is at longer wavelengths. It is the wavelength that divides the integral of a spectral power distribution into two equal parts as 2024PF80190 13 expressed by the formula λc = Σ λ*I(λ) / (Σ I( λ)), where the summation is over the wavelength range of interest, and I(λ) is the spectral energy density (i.e. the integration of the product of the wavelength and the intensity over the emission band normalized to the integrated intensity). The centroid wavelength may e.g. be determined at operation conditions. In embodiments, the first centroid wavelength (λc1) may be selected from the range of 600-660 nm, like from the range of 610-650 nm, such as from the range of 620-640 nm, especially from the range of 620-635 nm. Hence, in embodiments, the first luminescent material light may comprise, such as be, one or more of orange light and red light, such as especially red light. The terms “orange light” or “orange emission”, and similar terms, may especially relate to light having a wavelength in the range of about 590-620 nm. The terms “red light” or “red emission”, and similar terms, may especially relate to light having a wavelength in the range of about 620-780 nm. In embodiments, the first luminescent material light may comprise at least one emission band having a first full width at half maximum FWHM1 of ≤ 65 nm, such as ≤ 55 nm, especially ≤ 40 nm. Further, the first luminescent material light may comprise at least one emission band having a first full width at half maximum FWHM1 of ≤ 35 nm, such as ≤ 30 nm, especially ≤ 25 nm. Additionally or alternatively, the first luminescent material light may comprise the at least one emission band having a first full width at half maximum FWHM1of ≥ 2 nm, such as ≥ 5 nm, especially ≥ 7 nm. In embodiments, the first luminescent material light may comprise a plurality of emission bands, wherein at least one band may have the first full width at half maximum FWHM1. Additionally or alternatively, the first luminescent material light may comprise a plurality of emission bands, wherein essentially all of the emission bands may have the first full width at half maximum FWHM1. The term “emission band” may refer to the emission (spectral power distribution) resulting from a radiative transition of electrons from (vibrational levels of) a first higher-energy excited state to (vibrational levels of) a second lower-energy (ground) state, wherein a larger number of vibrational levels in (one or more of) the first excited state and second (ground) state results in a broader emission band (spanning a larger wavelength range). Further, the term “full width at half maximum” (or “FWHM”) refers to the width of (the spectral power distribution of) the emission band at half the maximum intensity of said emission band. The FWHM of an emission band may especially be determined at room temperature. The luminescent converter may comprise the first luminescent material in a first concentration C1. In embodiments, C1 may be selected from the range of ≥ 10 vol%, such as from the range of ≥ 15 vol%, especially from the range of ≥ 20 vol%, like from the 2024PF80190 14 range of ≥ 25 vol%. Additionally or alternatively, C1 may be selected from the range of ≤ 45 vol%, such as from the range of ≤ 40 vol%, especially from the range of ≤ 35 vol%, like from the range of ≤ 30 vol%. Further, in embodiments, the first concentration C1may be selected from the range of 10-45 vol%, such as from the range of 15-40 vol%, especially from the range of 20-35 vol%, like from the range of 25-30 vol%. In specific embodiments, the luminescent converter may comprise the first luminescent material in a first concentration C1, wherein the first concentration C1may be selected from the range of ≥ 20 vol%. Such a first concentration C1 may facilitate that part of the first light source light may be transmitted through the luminescent converter. Further, such a first concentration C1may facilitate that ≥ 5%, such as ≥ 10%, of a spectral power of the first light source light may be absorbed (and converted) by the first luminescent material. Hence, such a first concentration C1may facilitate providing (white) system light comprising the first luminescent material light and at least part of the first light source light. The luminescent converter may comprise one or more further luminescent converter luminescent materials, such as selected from the luminescent materials provided above. In such embodiments, relative to a total weight of the first luminescent material and the one or more further luminescent converter luminescent materials, the first luminescent material may be present (in the luminescent converter) with a weight percentage of ≤ 98%, such as ≤ 95%, especially ≤ 90%. That is, a luminescent material content of the luminescent converter may consist for at most 98%, such as at most 95%, especially at most 90%, of the first luminescent material. Alternatively, a luminescent material content of the luminescent converter may consist for at least 70%, such as at least 80%, especially at least 90%, including (essentially) 100%, of the first luminescent material. Hence, in specific embodiments, a luminescent material content of the luminescent converter may consist for at least 80% of the first luminescent material. Such a luminescent material content may facilitate that the light generated by the luminescent converter (upon irradiation with first light source light) may largely consist of first luminescent material light. As indicated above, the luminescent converter may be configured in a light receiving relationship with the first solid state light source. Especially, the luminescent converter may be configured downstream from the first solid state light source. The terms “downstream” and “upstream” relate to an arrangement of items or features relative to the propagation of the light from a light generating means (here especially the solid state light source), wherein relative to a first position within a beam of light from the light generating means, a second position in the beam of light closer to the light generating means is 2024PF80190 15 “upstream”, and a third position within the beam of light further away from the light generating means is “downstream”. The luminescent converter may be configured in physical contact and covering the first solid state light source. In such embodiments, the luminescent converter may be configured as a coating. Alternatively, the luminescent converter may be configured as a self-supporting luminescent body. In such embodiments, the luminescent converter may be configured at a non-zero distance (d1) from (a face of) the first solid state light source. The non-zero distance (d1) may be selected from the range of ≥ 5 µm, such as from the range of ≥ 10 µm, especially from the range of ≥ 25 µm. Additionally or alternatively, the non-zero distance (d1) may be selected from the range of ≤ 10 cm, such as from the range of ≤ 5 cm, especially from the range of ≤ 1 cm. Further, the luminescent converter may be physically separated from the first solid state light source. Hence, in specific embodiments, the luminescent converter may be configured at a non-zero distance (d1) from the first solid state light source. The first solid state light source may produce heat during operation. Hence, configuring the luminescent converter at a non-zero distance (d1) from the first solid state light source may reduce heating of the luminescent converter during operation (of the light generating system) by reducing thermal coupling between the first solid state light source and the luminescent converter. The light generating system may comprise the first solid state light source. Further, the light generating system may comprise a plurality of first solid state light sources. Additionally or alternatively, the light generating system may comprise one or more solid state light sources. The luminescent converter may be configured downstream of and in a light receiving relationship with at least one of the one or more solid state light sources. Yet, especially, the luminescent converter may be configured downstream of and in a light receiving relationship with all of the one or more solid state light sources. Further, at least one of the one or more solid state light sources may comprise the (or a) first solid state light source. In specific embodiments, all of the one or more solid state light sources may comprise a first solid state light source. In embodiments, at least one of the one or more solid state light sources may be configured to generate light source light having at least some intensity in the wavelength range of 380-490 nm (see also below). Alternatively, each of the one or more solid state light sources may be configured to generate light source light having a spectral power distribution, wherein ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, each of the one or more solid state light sources may be configured to generate light source light having a spectral power distribution, wherein 2024PF80190 16 ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of ≤ 500 nm, such as in the wavelength range of 380-499 nm. Hence, in specific embodiments, the light generating system may comprise one or more solid state light sources, wherein at least one of the one or more solid state light sources may comprise the first solid state light source, wherein each of the one or more solid state light sources may be configured to generate light source light having a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. A light generating system comprising (one or) more solid state light sources may facilitate providing system light having a higher intensity. Further, solid state light sources configured to generate light source light having ≤ 2% of the spectral power in the wavelength range of 380-490 nm may provide blue-free light source light. Such one or more solid state light sources may thus provide the benefit that no blue light may be emitted upon damage to and / or degradation of the luminescent converter. Hence, a light generating system comprising such one or more solid state light sources may be especially applicable for cleanroom applications, where the emission of blue light is undesired. The light generating system may further comprise a second solid state light source. The second solid state light source may be selected from the group comprising a light emitting diode (LED), a laser diode, a superluminescent diode, and a multi-junction light emitting diode, though other options may also be possible (see below). The second solid state light source may be configured to generate second light source light. The second light source light may have a second peak wavelength (λp2) selected from the range of 420-490 nm, such as from the range of 430-490 nm, especially from the range of 440-470 nm, like from the range of 440-465 nm. Especially, the second light source light may have a second spectral power distribution, wherein ≥ 80%, such as ≥ 90%, especially ≥ 95%, including (essentially) 100%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 420-490 nm, such as especially in the wavelength range of 430-490 nm. Hence, the second light source light may be one or more of violet light and blue light, such as especially blue light. The term “violet light”, and similar terms, may especially relate to light having a wavelength in the range of about 380-440 nm. The second solid state light source may be comprised by the one or more solid state light sources. That is, in embodiments, at least one of the one or more solid state light sources may comprise the second solid state light source. In embodiments, the light generating system may thus comprise one or more (especially a plurality of) solid state light sources, wherein at least one of the one or more 2024PF80190 17 solid state light sources may be configured to generate light source light having a spectral power distribution, wherein ≥ 70%, such as ≥ 80%, especially ≥ 90%, including (essentially) 100%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. The luminescent converter may be configured in a light receiving relationship with (i.e., downstream of) the second solid state light source. Further, the first luminescent material may be configured to convert at least part of the second light source light received by the first luminescent material into first luminescent material light. Hence, in specific embodiments, the light generating system may further comprise a second solid state light source, wherein the second solid state light source may be configured to generate second light source light having a second peak wavelength (λp2) selected from the range of 430-490 nm; wherein the luminescent converter may be configured in a light receiving relationship with the second solid state light source; wherein the first luminescent material may be configured to convert at least part of the second light source light received by the first luminescent material into first luminescent material light. The first luminescent material may have a higher absorption at the second peak wavelength (λp2) than at the first peak wavelength (λp1). Hence, a light generating system comprising a second solid state light source may provide the benefit that the first concentration C1may be reduced. Further, a second solid state light source generating violet or blue light may facilitate providing system light with a higher correlated color temperature (CCT) and / or color rendering index (CRI). As indicated above, the first luminescent material may be configured to convert at least part of the second light source light received by the first luminescent material into first luminescent material light. Especially, the first luminescent material may be configured to convert ≤ 98%, such as ≤ 95%, especially ≤ 90%, of (a spectral power of) the second light source light received by the first luminescent material into first luminescent material light. Alternatively, the first luminescent material may be configured to convert ≥ 80%, such as ≥ 90%, especially ≥ 95%, including (essentially) 100%, of (a spectral power of) the second light source light received by the first luminescent material into first luminescent material light. The luminescent converter may comprise at least 1.1 times, such as at least 1.2 times, especially at least 1.3 times, an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter. Further, the luminescent converter may comprise at least 1.5 times, such as at least 2 times, especially at least 3 times, an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter. Additionally or alternatively, the luminescent converter may comprise at most 7 times, such as at most 5 2024PF80190 18 times, especially at most 4 times, an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter. Hence, the luminescent converter may comprise 1.5-7 times, such as 2-5 times, especially 3-4 times, an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter. In such embodiments, the second peak wavelength (λp2) may especially be selected from the range of 435-470 nm, like from the range of 440-465 nm, especially from the range of 445-460 nm. Hence, in specific embodiments, one or more may apply of: (A) the luminescent converter may comprise at least 1.2 times an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter; and (B) the second peak wavelength (λp2) may be selected from the range of 440-465 nm; wherein the luminescent converter may comprise 2-5 times an amount of the first luminescent material needed to transmit at most 2% of the second light source light received by the luminescent converter. Such a configuration of the luminescent converter may facilitate that essentially all of the second light source light may be converted into first luminescent material light. Further, such a configuration of the luminescent converter may facilitate that, even upon partial degradation of the first luminescent material, enough first luminescent material may remain such that essentially no (blue) second light source light may be transmitted through the luminescent converter. In embodiments, at least part of the first light source light may be transmitted through the luminescent converter. Further, the luminescent converter may have a first major face and a second major face, wherein the second major face may be configured opposite the first major face. In embodiments, the first (and / or second) light source light may be incident on the first major face of the luminescent converter, and the first luminescent material light (and transmitted first light source light) may exit the luminescent converter via the second major face. Hence, in specific embodiments, the luminescent converter may be configured in a transmissive mode. Herein, the term “transmissive mode” may indicate that when at least part of the (first) light source light is propagating in the same direction from the luminescent converter as it was propagating to the luminescent converter directly upstream of the luminescent converter, it may have a direction overlapping with the direction in which the (first) luminescent material light escapes from the light generating system. A transmissive mode may provide the benefit that the construction of the light generating system may be relatively simple, as few extra components (such as e.g. reflectors and / or dichroic mirrors) 2024PF80190 19 may be needed to guide the transmitted first (and / or second) light source light and first luminescent material light to a light exit of the light generating system. Yet, in alternative embodiments, the luminescent converter may be configured in a reflective mode. Herein, the term “reflective mode” may indicate that when (first) light source light is reflected at the luminescent converter, it may have a direction overlapping with the direction in which the luminescent material light escapes from the system. Hence, in the reflective mode, the first (and / or second) light source light may be incident on the first major face of the luminescent converter, and the first luminescent material light (and reflected first light source light) may exit the luminescent converter via the first major face. Configuring the luminescent converter in the reflective mode may improve thermal management, as the absorption and conversion of light may be spread over a larger optical path length within the luminescent converter, thus distributing the correspondingly generated heat over a larger volume within the luminescent converter. Further, as the path length of the first (and / or second) light source light in the luminescent converter may be doubled, the reflective mode may facilitate reducing the first concentration C1. The luminescent converter may further comprise a second luminescent material. The second luminescent material may be any of the luminescent materials indicated above. The second luminescent material may comprise quantum structures, such as quantum dots or quantum rods. Yet, especially, the second luminescent material may comprise a phosphor. In specific embodiments, the second luminescent material may be selected from the group of oxynitride luminescent materials and nitride luminescent materials. Such a second luminescent material may provide second luminescent material light having a broad (FWHM ≥ 60 nm) emission band, thereby facilitating increasing the CRI of the system light (comprising the second luminescent material light). Further, such a second luminescent material may be relatively stable. Additionally or alternatively, the second luminescent material may comprise a luminescent material of the type MAlSiN3:Eu2+, wherein M may comprise one or more of Ba, Sr, and Ca (see also above). Further, in embodiments, the second luminescent material may comprise a luminescent material of the type M1−xLi3−2yAl1+2y−zSizO4−4y−zN4y+z:Eux, wherein M comprises one or more of Ca, Sr, and Ba, wherein 0 < x ≤ 0.04, wherein 0 ≤ y ≤ 1, wherein 0 ≤ z ≤ 0.05, and wherein y + z ≤ 1. Additionally or alternatively, the second luminescent material may comprise a SiAlON-type phosphor, such as selected from the group comprising (a) Si12–m–nAlm+nOnN16–n:Eu2+, (b) Si6–nAlnOnN8–n:Eu2+, wherein 0 ≤ n ≤ 4.2, and (c) Si2–nAlnO1+nN2–n:Eu2+, wherein 0 ≤ n ≤ 0.2. Hence, in embodiments, the second luminescent 2024PF80190 20 material may comprise one or more of an oxynitride luminescent material, a nitride luminescent material, a luminescent material of the type MAlSiN3:Eu2+, an SLA-type phosphor, and a SiAlON-type phosphor. The second luminescent material may especially be different from the first luminescent material. Especially, the second luminescent material may comprise a different type of luminescent material than the first luminescent material. Alternatively, the first and second luminescent material may each comprise the same type(s) of luminescent material(s), wherein a composition of the (type(s) of) luminescent material(s) may differ between the first and second luminescent material. The second luminescent material may be configured to convert (at least) part of the first light source light received by the second luminescent material into second luminescent material light. Especially, the second luminescent material may be configured to convert ≥ 45%, such as ≥ 50%, especially ≥ 55%, of (a spectral power of) the first light source light received by the second luminescent material into second luminescent material light. Additionally or alternatively, the second luminescent material may be configured to convert ≤ 70%, such as ≤ 65%, especially ≤ 60%, of (a spectral power of) the first light source light received by the second luminescent material into second luminescent material light. Further, the second luminescent material may be configured to convert (at least) part of the second light source light received by the second luminescent material into second luminescent material light. Especially, the second luminescent material may be configured to convert ≥ 85%, such as ≥ 90%, especially ≥ 95%, including (essentially) 100%, of (a spectral power of) the second light source light received by the second luminescent material into second luminescent material light. Alternatively, the second luminescent material may be configured to convert ≤ 98%, such as ≤ 95%, especially ≤ 90%, of (a spectral power of) the second light source light received by the second luminescent material into second luminescent material light. The second luminescent material light may have a second centroid wavelength (λc2). The second centroid wavelength (λc2) may be selected from the range of 590-680 nm, such as from the range of 600-660 nm, especially from the range of 600-650 nm. Hence, the second luminescent material light may comprise, such as be, one or more of orange light and red light, such as especially red light. The second centroid wavelength (λc2) may be (roughly) equal to the first centroid wavelength (λc1), such as differ by ≤ 5 nm, especially by ≤ 2 nm, including by (essentially) 0 nm. Alternatively, the second centroid wavelength (λc2) may be different from the first centroid wavelength (λc1). In embodiments, |λc2-λc1| ≥ 0 nm, such as 2024PF80190 21 |λc2-λc1| ≥ 5 nm, especially |λc2-λc1| ≥ 10 nm. Additionally or alternatively, in embodiments, |λc2-λc1| ≤ 50 nm, such as |λc2-λc1| ≤ 40 nm, especially |λc2-λc1| ≤ 30 nm. The second luminescent material light may comprise at least one emission band having a second full width at half maximum FWHM2 of ≥ 50 nm, such as ≥ 60 nm, especially ≥ 70 nm. Additionally or alternatively, the second luminescent material light may comprise the at least one emission band having a second full width at half maximum FWHM2 of ≤ 200 nm, such as ≤ 175 nm, especially ≤ 150 nm. The second luminescent material light may comprise a plurality of emission bands, wherein at least one band may have the second full width at half maximum FWHM2. Alternatively, the second luminescent material light may comprise a single emission band, wherein said emission band may have the second full width at half maximum FWHM2. In embodiments, the light generating system may be configured to generate system light comprising the second luminescent material light. Especially, the light generating system may be configured to generate system light comprising the first luminescent material light, the second luminescent material light, and at least part of the first light source light (and optionally at least part of the second light source light). In such embodiments, the system light may be white light having a CCT selected from the range of 1300-4000 K, such as from the range of 1500-3400 K, especially from the range of 1700- 3000 K. Hence, in specific embodiments, the luminescent converter may comprise a second luminescent material, wherein the second luminescent material may be configured to convert part of the first light source light received by the second luminescent material into second luminescent material light; wherein the second luminescent material light may have a second centroid wavelength (λc2) selected from the range of 600-660 nm; wherein the second luminescent material light may comprise at least one emission band having a second full width at half maximum FWHM2 of ≥ 60 nm; and wherein the system light may further comprise the second luminescent material light. A luminescent converter comprising a first and second luminescent material may facilitate providing (combined) luminescent material light having a broader spectral power distribution, thereby improving the CRI of the system light. The luminescent converter may comprise the second luminescent material in a second concentration C2. In embodiments, C2 may be selected from the range of ≥ 1 vol%, such as from the range of ≥ 2 vol%, especially from the range of ≥ 3 vol%. Additionally or alternatively, C2 may be selected from the range of ≤ 35 vol%, such as from the range of ≤ 25 vol%, especially from the range of ≤ 20 vol%. Further, in embodiments, C2≥ 0.1*C1, such as 2024PF80190 22 C2 ≥ 0.2*C1, especially C2 ≥ 0.3*C1. Additionally or alternatively, in embodiments, C2 ≤ C1, such as C2 ≤ 0.9*C1, especially C2 ≤ 0.75*C1. Hence, in specific embodiments, the luminescent converter may comprise (i) the first luminescent material in a first concentration C1, and (ii) the second luminescent material in a second concentration C2; wherein C2 ≤ C1. The second luminescent material may have a higher absorption at the first peak wavelength (λp1) than the first luminescent material. Hence, a lower second concentration C2 than first concentration C1may facilitate that the spectral power distribution of the system light may comprise more similar contributions from the first luminescent material light and the second luminescent material light. As indicated above, the luminescent converter may comprise one or more further luminescent converter luminescent materials. In embodiments, a luminescent material content of the luminescent converter may consist for at least 80%, such as at least 90%, especially at least 95%, including (essentially) 100%, of the first luminescent material and the second luminescent material. Alternatively, a luminescent material content of the luminescent converter may consist for at most 98%, such as at most 95%, especially at most 90%, of the first luminescent material and the second luminescent material. The light generating system may be configured to generate system light comprising (a) the first luminescent material light, (b) optionally the second luminescent material light, (c) the first light source light, and (d) optionally the second light source light. Especially, the system light may comprise (at least) the first luminescent material light and at least part of the first light source light. Further, the system light may be white light. The term “white light”, and similar terms, herein, is known to the person skilled in the art. It may especially relate to light having a correlated color temperature (CCT) between about 1800 K and 20000 K, such as between 2000 and 20000 K, especially between 2700 and 20000 K, for general lighting especially in the range of about 2000-7000 K, such as in the range of 2700- 6500 K. In embodiments, the correlated color temperature (CCT) is especially within about 20 SDCM (standard deviation of color matching) from the BBL (black body locus), such as within 15 SDCM from the BBL, especially within 10 SDCM from the BBL, like within 5 SDCM from the BBL. In embodiments, the system light may have a CCT selected from the range of ≥ 1300 K, such as from the range of ≥ 1400 K, especially from the range of ≥ 1500 K, like from the range of ≥ 1700 K. Additionally or alternatively, the system light may have a CCT selected from the range of ≤ 4500 K, such as from the range of ≤ 4000 K, especially from the range of ≤ 3400 K, like from the range of ≤ 3000 K. Hence, the system light may have a CCT selected from the range of 1300-4500 K, such as from the range of 1400-4000 K, especially from the range of 1500-3400 K, like from the range of 1700-3000 K. In 2024PF80190 23 embodiments, the system light may have a CCT selected from the range of ≥ 1800, such as selected from the range of 1800-3000 K, especially from the range of 1800-2700 K, like from the range of 1800-2200 K. Additionally or alternatively, the system light may have a CCT selected from the range of ≤ 2500 K, like from the range of ≤ 2200 K, especially from the range of ≤ 2000 K. Further, the system light may have a color rendering index (CRI) of at least 50, such as at least 55, especially at least 60. The system light may have a (CRI) R9 score of ≥ 55, such as ≥ 60, especially ≥ 65. The CCT of the system light may depend on the first peak wavelength (λp1) of the first light source light. In embodiments, the first peak wavelength (λp1) may be selected from the range of 500-510 nm, and the system light may have a CCT selected from the range of 1800-3600 K, such as from the range of 2000-3400 K, especially from the range of 2000- 3000 K. Hence, in specific embodiments, the first peak wavelength (λp1) may be selected from the range of 500-510 nm, and the system light may have a correlated color temperature selected from the range of 2000-3400 K. The first (and / or second) luminescent material(s) may have a higher absorption at 500 nm ≤ λp1≤ 510 nm, facilitating reducing the first (and / or second) concentration(s) C1 (and / or C2). Further, a CCT of 2000-3400 K may provide warm white light. Alternatively, the first peak wavelength (λp1) may be selected from the range of 510-520 nm, and the system light may have a CCT selected from the range of 1300-2200 K, such as from the range of 1500-2000 K, especially from the range of 1700-2000 K. Hence, in specific embodiments, the first peak wavelength (λp1) may be selected from the range of 510-520 nm, and the system light may have a correlated color temperature selected from the range of 1500-2000 K. A light generating system with 510 nm ≤ λp1 ≤ 520 nm may provide first light source light (and / or system light) having relatively less intensity in the wavelength range of ≤ 490 nm than a light generating system with 500 nm ≤ λp1 ≤ 510 nm. The (white) system light (comprising part of the first light source light and optionally part of the second light source light) may have a color point, such as especially a color point in the CIE 1931 color space. In embodiments, the color point (in the CIE 1931 color space) of the system light may be within 12 SDCM from the BBL, such as within 10 SDCM, especially within 7 SDCM. Hence, in specific embodiments, the system light may have a color point within 10 SDCM from the BBL in the CIE 1931 color space. Such system light may deviate relatively little from white light produced using a convention lighting system. 2024PF80190 24 As indicated above, in specific embodiments the system light may comprise part of the second light source light. System light comprising part of the second light source light may have a higher CCT and / or CRI than system light (only) comprising part of the first light source light. In embodiments, the system light may have a spectral power distribution, wherein at most 12%, such as at most 10%, especially at most 5%, of the spectral power in the wavelength range of 380-780 nm may be provided by the second light source light. Hence, in specific embodiments, the system light may have a spectral power distribution, wherein at most 10% of the spectral power in the wavelength range of 380-780 nm may be provided by the second light source light. Such system light may especially have a high (e.g. ≥ 2700 K) CCT. Further, such system light may have a relatively high CRI. As indicated above, the first (and / or second) luminescent material(s) may be configured to convert (essentially) all of the second light source light received by the first (and / or second) luminescent material(s) into first (and / or second) luminescent material light. Hence, in embodiments, the system light may be (essentially) free from second light source light. Further, the system light may be (essentially) free from blue light. That is, the system light may have a spectral power distribution, wherein ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be provided in the wavelength range of 380-490 nm. Further, the system light may have a spectral power distribution, wherein ≤ 5%, such as ≤ 2%, especially ≤ 1%, including (essentially) 0%, of the spectral power in the wavelength range of 380-780 nm may be provided in the wavelength range of ≤ 490 nm, such as especially in the wavelength range of 380-489 nm. In such embodiments, the luminescent converter may be configured in the reflective mode. Yet, especially, in such embodiments the luminescent converter may be configured in the transmissive mode. Hence, in specific embodiments, (the luminescent converter may be configured in a transmissive mode, wherein) the system light may have a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm may be provided in the wavelength range of 380-490 nm. Such system light may especially be (essentially) free from blue light. Hence, such system light may be suitable for cleanroom or darkroom applications. The first solid state light source may be controlled separately from the second solid state light source. Especially, the light generating system may comprise a control system. The control system may be configured to individually control the first solid state light source and the second solid state light source. Especially, the control system may be configured to individually control an intensity of the first light source light and an intensity of 2024PF80190 25 the second light source light. Further, the control system may be configured to individually control the one or more solid state light sources. Hence, in specific embodiments, the light generating system may further comprise a control system, wherein the control system may be configured to individually control the first solid state light source and the second solid state light source. Such a control system may facilitate adjusting one or more of the CCT, CRI, color point, and intensity of the system light. The term “controlling” and similar terms especially refer at least to determining the behavior or supervising the running of an element. Hence, herein the term “controlling” and similar terms may include imposing behavior on an element and / or monitoring the element. The controlling of the element can be done with a control system. The control system and the element may thus at least temporarily, or permanently, functionally be coupled. The element may comprise the control system. The control system and element may not be physically coupled. Control can be done via wired and / or wireless control. A control system may comprise or may be functionally coupled to a user interface. The control system may also be configured to receive and execute instructions from a remote control. The control system may be controlled via an App on a device, such as a portable device. In such embodiments the control system of the lighting system may be a slave control system. The lighting system may also comprise means for communicating with other systems or devices, such as on the basis of Bluetooth, Thread, WIFI, LiFi, ZigBee, BLE or WiMAX, or another wireless technology. The control system may control in dependence of one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer. The term “timer” may refer to a clock and / or a predetermined time scheme. Some general embodiments relating to the light source will be provided next. The term “light source” may in principle relate to any light source known in the art. In a specific embodiment, the light source may comprise an LED. The term “light source” may also relate to a plurality of (essentially identical (or different)) light sources, such as 2-2000 (LED) light sources. The phrase “different light sources”, and similar phrases, may refer to a plurality of solid state light sources selected from at least two different bins. Likewise, the phrase “identical light sources”, and similar phrases, may refer to a plurality of solid state light sources selected from the same bin. Hence, the term LED may also refer to a plurality of LEDs. Further, the term “light source” may in embodiments also refer to a so-called chip-on- board (COB) light source. The term “COB” especially refers to LED chips in the form of a semiconductor chip that is neither encased nor connected but directly mounted onto a substrate, such as a PCB. Hence, a plurality of light emitting semiconductor light sources 2024PF80190 26 may be configured on the same substrate. In embodiments, a COB is a multi LED chip configured together as a single lighting module. The term “light source” may also refer to a chip scale package (CSP) and / or a chip scale packaged (CSP) LED. A CSP may comprise a single solid state die (such as a LED) with provided thereon a luminescent material comprising layer. The term “light source” may also refer to a midpower package. A midpower package may comprise one or more solid state die(s). The die(s) may be covered by a luminescent material comprising layer. The die dimensions may be equal to or smaller than 2 mm, such as in the range of e.g. 0.2-2 mm. Herein, the term “light source” may also especially refer to a small solid state light source, such as having a mini size or micro size. For instance, the light sources may comprise one or more of mini LEDs and micro LEDs, such as especially micro LEDs or “microLEDs” or “µLEDs”. Herein, the term mini size or mini LED especially refers to solid state light sources having dimensions, such as die dimension, especially length and width, selected from the range of 100 µm – 1 mm. Herein, the term µ size or micro LED especially refers to solid state light sources having dimensions, such as die dimension, especially length and width, selected from the range of 100 µm and smaller. The light source may have a light escape surface. For LEDs it may for instance be the LED die, or when a resin is applied to the LED die, the outer surface of the resin. The term escape surface especially relates to that part of the light source, where the light actually leaves or escapes from the light source. The light source is configured to provide a beam of light. This beam of light (thus) escapes from the light exit surface of the light source. The term “light source” may refer to a semiconductor light-emitting device, such as an LED, a resonant cavity light emitting diode (RCLED), a vertical cavity laser diode (VCSELs), an edge emitting laser, etc... The term “light source” may also refer to an organic light-emitting diode (OLED), such as a passive-matrix (PMOLED) or an active-matrix (AMOLED). In an embodiment, the light source comprises a LED. The terms “light source” or “solid state light source” may also refer to a superluminescent diode (SLED). Especially, the term “solid state light source” may refer to semiconductor light sources, such as a light emitting diode (LED), a laser diode, a superluminescent diode, or a multi-junction diode. The light source may comprise one or more micro-optical elements (array of micro lenses) downstream of a single solid-state light source, or downstream of a plurality of solid state light sources (i.e. e.g. shared by multiple LEDs). In embodiments, the light source may comprise a LED with on-chip optics. The light source may comprise pixelated single LEDs (with or without optics) (offering in embodiments on-chip beam steering). In 2024PF80190 27 embodiments, the light source may be configured to provide primary radiation, which is used as such, such as e.g. a blue light source, like a blue LED. Such LEDs, which may not comprise a luminescent material may be indicated as direct color LEDs. The term “light source” may refer to a light generating element as such, like e.g. a solid state light source, or e.g. to a package of the light generating element, such as a solid state light source, and one or more optics, like a lens, a collimator. In embodiments, the term “light source” may also refer to a combination of a light source, like an LED, and an optical filter, which may change the spectral power distribution of the light generated by the light source. In specific embodiments, the light source may be selected from the group of laser diodes and superluminescent diodes. In other embodiments, the light source may comprise an LED or multi-junction (light emitting) diode. The light source may especially be configured to generate light source light having an optical axis (O), (a beam shape,) and a spectral power distribution. The light source light may in embodiments comprise one or more bands, having band widths as known for lasers The term “laser light source” especially refers to a laser. Such laser may especially be configured to generate laser light source light having one or more wavelengths in the UV, visible, or infrared, especially having a wavelength selected from the wavelength range of 200-2000 nm, such as from the wavelength range of 300-1500 nm. The term “laser” especially refers to a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. Especially, the term “laser” may refer to a solid-state laser. In specific embodiments, the terms “laser” or “laser light source”, or similar terms, may refer to a laser diode (or diode laser). Hence, in embodiments the light source comprises a laser light source. In embodiments, the terms “laser” or “solid state laser” or “solid state material laser” may refer to one or more of a semiconductor laser diodes, such as GaN, InGaN, AlGaInP, AlGaAs, InGaAsP, lead salt, vertical cavity surface emitting laser (VCSEL), quantum cascade laser, hybrid silicon laser, etc. The term “solid state material laser”, and similar terms, may thus refer to a solid state laser like based on a crystalline or glass body dopes with ions, like transition metal ions and / or lanthanide ions, to a fiber laser, to a photonic crystal laser, to a semiconductor laser, etc. In embodiments, the term “laser light source” may also refer to a plurality of (different or identical) laser light sources. In specific embodiments, the term “laser light source” may refer to a plurality N of (identical) laser light sources. In embodiments, N≥2, such as N≥5, especially N≥8. In this way, a higher brightness (of the laser light) may be obtained. Laser light sources may be arranged in a laser bank. The laser bank may comprise 2024PF80190 28 heat sinking and / or optics (e.g. a lens to collimate the laser light). Hence, in embodiments lasers in a laser bank (or “laser array bank”) may share the same optics. The laser light source may be configured to generate laser light source light (or “laser light”). The light source light may essentially consist of the laser light source light. The light source light may also comprise laser light source light of two or more (different or identical) laser light sources. For instance, the laser light source light of two or more (different or identical) laser light sources may be coupled into a light guide, to provide a single beam of light comprising the laser light source light of the two or more (different or identical) laser light sources. The light source light may thus be collimated (laser) light source light. The laser light source light may comprise one or more bands, having band widths as known for lasers. In embodiments, the band(s) may be relatively sharp line(s), such as having full width half maximum (FWHM) in the range of ≤20 nm at RT, such as ≤10 nm. Hence, the light source light may have a spectral power distribution (intensity on an energy scale as function of the wavelength) which may comprise one or more (narrow) bands. The beams (of light source light) may be focused or collimated beams of (laser) light source light. The term “focused” may especially refer to converging to a small spot. Focusing (of the laser light source light) may be executed with one or more optics, such as especially two (focusing) lenses. Collimation may be executed with one or more (other) optics, like collimation elements, such as lenses and / or parabolic mirrors. In embodiments, the beam of (laser) light source light may be relatively highly collimated, such as in embodiments ≤2° (FWHM), more especially ≤1° (FWHM), most especially ≤0.5° (FWHM). In embodiments, the light generating system may comprise a Chip-on-Board (COB). The Chip-on-Board may comprise a plurality of the first solid state light source. Optionally, the Chip-on-Board may further comprise a plurality of the second solid state light source. As indicated above, the term “COB” may especially refer to LED chips in the form of a semiconductor chip that is directly mounted onto a substrate. Hence, in embodiments, the COB may comprise a plurality of the first (and optionally second) solid state light source, wherein the first (and second) solid state light source may especially be (an) LED(s). Further, in embodiments, the Chip-on-Board may comprise the luminescent converter (configured as a coating). The luminescent converter may be configured on top of (and in physical contact with) the plurality of first solid state light sources (and the optional plurality of second solid state light sources). Hence, in specific embodiments, the light generating system may comprise a Chip-on-Board (CoB), wherein the Chip-on-Board (CoB) may comprise (i) a plurality of the first solid state light source, and (ii) the luminescent converter, wherein the 2024PF80190 29 luminescent converter may be configured on top of the plurality of first solid state light sources. A light generating system comprising a COB may be relatively compact, as no separate holder is needed for the first (and / or second) solid state light sources and / or the luminescent converter. Further, a COB may be relatively easy to produce. Additionally or alternatively, the light generating system may comprise a LED filament. Hence, the light generating system may comprise (both) a CoB and a LED filament. Alternatively, the light generating system may comprise one of a CoB and a LED filament. LED filaments as such are known, and are e.g. described in US 8,400,051 B2, WO2020016058, WO2019197394, etc., which are herein incorporated by reference. In general, a LED filament may in embodiments comprise (i) a plurality of LEDs, arranged on (at least a first major surface of) an elongated carrier, and (ii) an elongated encapsulant covering the plurality of LEDs and at least part of the elongated carrier. The LED filament may in embodiments be defined by a filament length LF, a filament width WF, and a filament thickness TF. Further, the LED filament may have relatively high aspect ratios (LF / WF or LF / TF), such as 10*WF≤ LF≤ 900*WF, and 10*TF≤ LF≤ 900*TF. In some embodiments, the LED filament may be straight. In other embodiments, the LED filament may be curved. For instance, the filament may have a (2D or 3D) spiraling shape, (like) a helical shape. Further, as indicated, the LED filament may comprise an elongated carrier, solid state light sources, and an encapsulant. Especially, the elongated carrier may support the solid state light sources. The elongated carrier may e.g. comprise glass, quartz, metal, or sapphire. Further, the elongated carrier may e.g. comprise a polymeric material or (flexible) metal, e.g., a film or foil. The elongated carrier may be rigid (self-supporting), but may (in polymeric embodiments) also be flexible. Further, the elongated carrier may be light transmissive, translucent, or transparent for light, especially visible light. Alternatively, the carrier may be light reflective, especially reflective for one or more of the first (and / or second) light source light and the first (and / or second) luminescent material light, such as reflective for at least the first (and / or second) light source light and the first (and / or second) luminescent material light. In specific embodiments, the carrier may be diffuse reflective. In embodiments, the (elongated) carrier may comprise a first major surface at a first side of the carrier and a second major surface at a second side of the carrier, opposite to the first side. The solid state light sources may be arranged on at least one of these surfaces. Hence, at least part of, such as all of, the solid state light sources may be mounted onto the first major surface. Additionally or alternatively, at least part of the solid state light sources may be mounted onto the second major surface. Hence, the solid state light sources 2024PF80190 30 may be arranged, mounted and / or mechanically coupled on / to the carrier, wherein the carrier may especially be configured to mechanically and / or electrically support the LEDs. The LED filament may comprise one or more of LEDs, laser diodes, superluminescent diodes, and multi-junction diodes. Especially, the LED filament may comprise a plurality of LEDs. The (plurality of) solid state light sources may be arranged in an array (on the elongated carrier). The number of solid state light sources in the array may be ≥ 4, such as ≥ 8, even more especially ≥ 12, and may e.g. be up to 100, or yet even larger. In embodiments, the number of solid state light sources in the array may be selected from the range of 10-2000, such as from the range of 10-1500, especially from the range of 10-1000. The solid state light sources may be configured in a 1D (linear) array. Further, the solid state light sources may be configured in two 1D arrays, one on the first major surface of the elongated carrier and one on the second major surface. A 2D array of solid state light sources of n*m LEDs may also be possible. In embodiments, n may be selected from the range of 1- 4, such as 1-3, like 1-2, such as in embodiments 1 or in embodiments 2, and m may be selected from the range of larger than n, such as especially selected from the range of ≥ 4 (when n<4), like ≥ 6, such as ≥ 8. Hence, a 2D array of solid state light sources may especially have a (much) smaller number of rows (n) than the number of solid state light sources in those respective rows (m), such as n / m ≤0.2, like n / m ≤0.1, especially n / m ≤0.05. The LED filament may comprise an elongated encapsulant. The encapsulant may (at least partly) enclose the plurality of solid state light sources. Further, the encapsulant may (at least partly) enclose the elongated carrier, such as at least (part of) one of the first major and second major surface. In general, the encapsulant may be in contact with the elongated carrier and may at least partially enclose all of the solid state light sources. The encapsulant may be a continuous coating along the filament length LF, at one or both of the first major and the second major surface. Further, the encapsulant may at least partly enclose the solid state light sources, such as in embodiments at least 50% of the total number of solid state light sources in the array, such as at least 75%, especially at least 95%, up to 100%. The encapsulant may comprise the luminescent converter. Alternatively, the luminescent converter may be an encapsulant, i.e., the luminescent converter may be configured as an encapsulant. Additionally or alternatively, the encapsulant may comprise a light scattering material, configured embedded in an encapsulant material, e.g. a (flexible) polymer material (such as a silicone). In embodiments, the light scattering material may be configured to scatter (or “diffuse”) the first (and / or second) light source light and / or the first (and / or second) luminescent material light, especially in a direction transverse to a normal of 2024PF80190 31 the (first and / or second) major surface. In specific embodiments, the light scattering material may comprise light scattering particles, such as e.g. at least one of BaSO4, A12O3 and TiO2 particles. In embodiments, the LED filament may comprise multiple subfilaments. Hence, the light generating system may comprise a LED filament, wherein the LED filament may comprise a plurality of the first solid state light source arranged on an elongated carrier. Optionally, the LED filament may further comprise a plurality of the second solid state light source arranged on the elongated carrier. Further, the LED filament may comprise an elongated encapsulant configured in physical contact with and at least partially enclosing the plurality of first solid state light sources (and the optional plurality of second solid state light sources) and at least part of the elongated carrier. In embodiments, the elongated encapsulant may comprise the luminescent converter. Alternatively, the luminescent converter may be configured as an elongated encapsulant. Hence, in specific embodiments, the light generating system may comprise a LED filament, wherein the LED filament may comprise (i) a plurality of the first solid state light source arranged on an elongated carrier, and (ii) an elongated encapsulant configured in physical contact with and at least partially enclosing the plurality of first solid state light sources and at least part of the elongated carrier; wherein the elongated encapsulant may comprise the luminescent converter. A light generating system comprising a LED filament may facilitate using the light generating system in decorative light bulbs, as such a light generating system may better resemble a filament of a conventional fluorescent light bulb. The light generating system may be part of or may be applied in e.g. office lighting systems, household application systems, shop lighting systems, home lighting systems, accent lighting systems, spot lighting systems, theater lighting systems, fiber-optics application systems, projection systems, self-lit display systems, pixelated display systems, segmented display systems, warning sign systems, medical lighting application systems, indicator sign systems, decorative lighting systems, portable systems, automotive applications, (outdoor) road lighting systems, urban lighting systems, green house lighting systems, horticulture lighting, digital projection, or LCD backlighting. The light generating system (or luminaire) may be part of or may be applied in e.g. optical communication systems or disinfection systems. In yet a further aspect, the invention also provides a lamp or a luminaire comprising the light generating system as defined herein. The luminaire may further comprise a housing, optical elements, louvres, etc.. The lamp or luminaire may further comprise a housing enclosing the light generating system. The lamp or luminaire may 2024PF80190 32 comprise a light window in the housing or a housing opening, through which the system light may escape from the housing. In yet a further aspect, the invention also provides a projection device comprising the light generating system as defined herein. Especially, a projection device or “projector” or “image projector” may be an optical device that projects an image (or moving images) onto a surface, such as e.g. a projection screen. The projection device may include one or more light generating systems such as described herein. Hence, in an aspect the invention also provides a lighting device selected from the group of a lamp, a luminaire, a projector device, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising the light generating system as defined herein. Especially, in a second aspect, the invention provides a lighting device selected from the group of a lamp and a luminaire, comprising the light generating system as defined herein. The lighting device may comprise a housing or a carrier, configured to house or support, one or more elements of the light generating system. The terms “light” and “radiation” are herein interchangeably used, unless clear from the context that the term “light” only refers to visible light. The terms “light” and “radiation” may thus refer to UV radiation, visible light, and IR radiation. In specific embodiments, especially for lighting applications, the terms “light” and “radiation” refer to (at least) visible light. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which: Figs.1A-1C schematically depict embodiments of the light generating system; Fig.2 schematically depicts another embodiment of the light generating system; Fig.3 schematically depicts an embodiment of the system light; Fig.4A schematically depicts an embodiment of the first luminescent material light; Fig.4B schematically depicts an embodiment of the system light; Fig.5 schematically depicts an embodiment of the light generating system comprising a LED filament; Fig.6 schematically depicts an embodiment of the light generating system comprising a COB; and 2024PF80190 33 Fig.7 schematically depicts an embodiment of the lighting device. The schematic drawings are not necessarily to scale. DETAILED DESCRIPTION OF THE EMBODIMENTS Fig.1A schematically depicts an embodiment of the light generating system 1000. The light generating system 1000 may comprise a first solid state light source 10 and a luminescent converter 2000. The first solid state light source 10 may be configured to generate first light source light 11 having a first peak wavelength λp1 selected from the range of 490-520 nm, such as selected from the range of 500-520 nm. Further, the luminescent converter 2000 may be configured in a light receiving relationship with the first solid state light source 10. The luminescent converter 2000 may comprise a first luminescent material 210. The first luminescent material 210 may be configured to convert part of the first light source light 11 received by the first luminescent material 210 into first luminescent material light 211. The first luminescent material light 211 may have a first centroid wavelength λc1 selected from the range of 610-650 nm. Further, the first luminescent material light 211 may comprise at least one emission band having a first full width at half maximum FWHM1 of ≤ 55 nm. The light generating system 1000 may be configured to generate system light 1001 comprising the first luminescent material light 211 and at least part of the first light source light 11. Especially, the system light 1001 may be white light having a correlated color temperature selected from the range of 1500-3400 K. Further, the system light 1001 may have a color point within 10 SDCM from the BBL in the CIE 1931 color space. The luminescent converter 2000 may comprise the first luminescent material 210 in a first concentration C1. The first concentration C1 may especially be selected from the range of ≥ 20 vol%. Fig.1B schematically depicts a further embodiment of the light generating system 1000. The luminescent converter 2000 may comprise a second luminescent material 220 (different from the first luminescent material 210). The second luminescent material 220 may be configured to convert part of the first light source light 11 (and optionally the second light source light 21, see Fig.1C) received by the second luminescent material 220 into second luminescent material light 221. The second luminescent material light 221 may have a second centroid wavelength λc2 selected from the range of 600-660 nm. Further, the second luminescent material light 221 may comprise at least one emission band having a second full width at half maximum FWHM2 of ≥ 60 nm. The system light 1001 may (further) comprise the second luminescent material light 221. Further, the luminescent converter 2000 may 2024PF80190 34 comprise (i) the first luminescent material 210 in a first concentration C1, and (ii) the second luminescent material 220 in a second concentration C2. In embodiments, C2 ≤ C1. Fig.1C schematically depicts a further embodiment of the light generating system 1000. The light generating system 1000 may further comprise a second solid state light source 20. The second solid state light source 20 may be configured to generate second light source light 21 having a second peak wavelength λp2 selected from the range of 430-490 nm. The luminescent converter 2000 may be configured in a light receiving relationship with the second solid state light source 20. Further, the first luminescent material 210 may be configured to convert at least part of the second light source light 21 received by the first luminescent material 210 into first luminescent material light 211. Similarly, the second luminescent material 220 may be configured to convert at least part of the second light source light 21 received by the second luminescent material 220 into second luminescent material light 221. Optionally, the system light 1001 may comprise part of the second light source light 21. Further, the light generating system 1000 may comprise a control system 300. The control system 300 may be configured to individually control the first solid state light source 10 and the second solid state light source 20. Fig.2 schematically depicts a further embodiment of the light generating system 1000. As depicted in Fig.2, the luminescent converter 2000 may be configured at a non-zero distance d1from the first solid state light source 10 (and the second solid state light source 20). The luminescent converter 2000 may be configured in the transmissive mode. Fig.3A schematically depicts an embodiment of the first luminescent material light 211. Reference 212 indicates the absorption and / or excitation spectrum of the first luminescent material 210. The first luminescent material 210 may especially comprise a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, at least comprising fluorine. The first luminescent material 210 may comprise a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein A may comprise (at least) Ti. The absorption / excitation spectrum of such a first luminescent material 210 is indicated by reference 212a, and the corresponding first luminescent material light 211 is indicated by reference 211a. Further, the first luminescent material 210 may comprise a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein A may comprise (at least) Si. Reference 212b indicates the absorption / excitation spectrum of such a first luminescent material 210, and reference 211b indicates the 2024PF80190 35 corresponding first luminescent material light. Additionally or alternatively, the first luminescent material 210 may comprise a luminescent material of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein A may comprise (at least) Ge. Reference 212c indicates the absorption / excitation spectrum of a first luminescent material 210 wherein A comprises (at least) Ge and Si (with corresponding first luminescent material light 211c), and reference 212d indicates the absorption / excitation spectrum of a first luminescent material 210 wherein A comprises (at least) Ge (with corresponding first luminescent material light 211d). The first luminescent material 210 may comprise (K,Rb)2(Si,Ti)F6:Mn4+, such as especially K2(Si,Ti)F6:Mn4+. Further, the first luminescent material 210 may comprise K2(Si1-xTix)F6:Mn4+, wherein x may be selected from the range of ≥ 0.6. Fig.3 schematically depicts an embodiment of the system light 1001 comprising the first luminescent material light 211 and the first light source light 11. As indicated above, the first luminescent material light 211 may have a first centroid wavelength (λc1) selected from the range of 610-650 nm, like from the range of 620-640 nm, especially from the range of 625-635 nm. In Fig.3, a first centroid emission wavelength (λc1) of 610 nm is indicated by reference λp1a, and a first centroid emission wavelength (λp1) of 650 nm is indicated by reference λp1b. Further, the first light source light 11 may have a first peak emission wavelength (λp1) selected from the range of 490-520 nm, such as about 500-520 nm. In Fig.3, a first peak emission wavelength (λp1) of 500 nm is indicated by reference λp1a, and a first peak emission wavelength (λp1) of 520 nm is indicated by reference λp1b. Further, the dashed lines indicate the color gamut of the system light 1001. That is, the dashed lines indicate the boundaries of the color gamut of the system light 1001, and the light generating system 1000 may be configured to generate system light 1001 having any color point selected from the color points within the boundaries. Especially, it is shown that the system light 1001 may be white light having a correlated color temperature selected from the range of 1500- 3400 K. Referring to Fig.4A, the (first) luminescent material of the type M’xM2-2xAX6 provides multiple narrow emission bands (“lines”) in (amongst others) the red wavelength range. Essentially each of these bands may have a full width half maximum well below 50 nm, such as below 20 nm. Of course, such narrow bands may (partly) merge into broader bands. However, it is also noted that the width of the narrow bands in the emission spectra may also (partly) be due to the spectral resolution of the measurement setup. Hence, the first luminescent material light 211 may have a first centroid wavelength (λc1) selected from the 2024PF80190 36 wavelength range of 610-650 nm, and may comprise one or more emission bands having a first full width half maximum (FWHM1) of ≤ 50 nm. Fig.4B schematically depicts an embodiment of the system light 1001. In embodiments, the first peak wavelength λp1 may be selected from the range of 500-510 nm, and the system light 1001 may have a correlated color temperature selected from the range of 2000-3400 K. Alternatively, the first peak wavelength λp1 may be selected from the range of 510-520 nm, and the system light 1001 may have a correlated color temperature selected from the range of 1500-2000 K. The system light 1001 may (essentially) be free from the second light source light 21. Especially, the luminescent converter 2000 may comprise at least 1.2 times an amount of the first luminescent material 210 needed to transmit at most 2% of the second light source light 21 received by the luminescent converter 2000. Alternatively, the second peak wavelength λp2 may be selected from the range of 440-465 nm, and the luminescent converter 2000 may comprise 2-5 times an amount of the first luminescent material 210 needed to transmit at most 2% of the second light source light 21 received by the luminescent converter 2000. The system light 1001 may have a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm may be provided in the wavelength range of 380-490 nm. Fig.5 schematically depicts an embodiment of the light generating system 1000 comprising one or more solid state light sources 100. At least one of the one or more solid state light sources 100 may comprise the first solid state light source 10. Further, each of the one or more solid state light sources 100 may be configured to generate light source light 101 having a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, Fig.4 schematically depicts an embodiment of the light generating system 1000 comprising a LED filament 400. The LED filament 400 may comprise (i) a plurality of the first solid state light source 10 (and optionally a plurality of the second solid state light source 20) arranged on an elongated carrier 5, and (ii) an elongated encapsulant 410 configured in physical contact with and at least partially enclosing the plurality of first solid state light sources 10 (and the optional plurality of second solid state light sources 20) and at least part of the elongated carrier 5. The elongated encapsulant 410 may comprise the luminescent converter 2000. Fig.6 schematically depicts a light generating system 1000 comprising a Chip-on-Board 500. The Chip-on-Board (CoB) 500 may comprise (i) a plurality of the first solid state light source 10 (and optionally a plurality of the second solid state light source 20), 2024PF80190 37 and (ii) the luminescent converter 2000. The luminescent converter 2000 may be configured on top of the plurality of first solid state light sources 10 (and the optional plurality of second solid state light sources 20). In the CoB 500, the plurality of first solid state light sources 10 may be directly mounted onto a substrate 6 (e.g. a PCB). Fig.7 schematically depicts an embodiment of a luminaire 2 comprising the light generating system 1000 as described above. Reference 301 indicates a user interface which may be functionally coupled with the control system 300 of the light generating system 1000. Fig.7 also schematically depicts an embodiment of lamp 1 comprising the light generating system 1000. Hence, Fig.6 schematically depicts embodiments of a lighting device 1200 selected from the group of a lamp 1 and a luminaire 2, comprising the light generating system 1000 as described herein. Reference 3 indicates a projector device, which may also comprise the light generating system 1000. Lighting device light escaping from the lighting device 1200 is indicated with reference 1201. Lighting device light 1201 may essentially consist of system light 1001, and may in specific embodiments be system light 1001. Reference 1300 refers to a space, such as a room. Reference 1305 refers to a floor and reference 1310 to a ceiling; reference 1307 refers to a wall. The term “plurality” refers to two or more. The terms “substantially” or “essentially” herein, and similar terms, will be understood by the person skilled in the art. The terms “substantially” or “essentially” may also include embodiments with “entirely”, “completely”, “all”, etc. Hence, in embodiments the adjective substantially or essentially may also be removed. Where applicable, the term “substantially” or the term “essentially” may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term “comprise” also includes embodiments wherein the term “comprises” means “consists of”. The term “and / or” especially relates to one or more of the items mentioned before and after “and / or”. For instance, a phrase “item 1 and / or item 2” and similar phrases may relate to one or more of item 1 and item 2. The term “comprising” may in an embodiment refer to “consisting of” but may in another embodiment also refer to “containing at least the defined species and optionally one or more other species”. Use of the verb “to comprise” and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited 2024PF80190 38 to”. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation. It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The invention also provides a control system that may control the device, apparatus, or system, or that may execute the herein described method or process. Yet further, the invention also provides a computer program product, when running on a computer which is functionally coupled to or comprised by the device, apparatus, or system, controls one or more controllable elements of such device, apparatus, or system. The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.

Claims

2024PF80190 39 CLAIMS:

1. A light generating system (1000) comprising a first solid state light source (10) and a luminescent converter (2000), wherein: the first solid state light source (10) is configured to generate first light source light (11) having a first peak wavelength (λp1) selected from the range of 490-520 nm; the luminescent converter (2000) is configured in a light receiving relationship with the first solid state light source (10); wherein the luminescent converter (2000) comprises a first luminescent material (210); wherein the first luminescent material (210) comprises a luminescent material of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, at least comprising fluorine; wherein the first luminescent material (210) is configured to convert part of the first light source light (11) received by the first luminescent material (210) into first luminescent material light (211); wherein the first luminescent material light (211) has a first centroid wavelength (λc1) selected from the range of 610-650 nm; wherein the first luminescent material light (211) comprises at least one emission band having a first full width at half maximum FWHM1 of ≤ 55 nm; and the light generating system (1000) is configured to generate system light (1001) comprising the first luminescent material light (211) and at least part of the first light source light (11); wherein the system light (1001) is white light having a correlated color temperature selected from the range of 1500-3400 K.

2. The light generating system (1000) according to claim 1, wherein the first luminescent material (210) consists of a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, at least comprising fluorine.2024PF80190 40 3. The light generating system (1000) according to any one of the preceding claims, wherein the first luminescent material (210) comprises a luminescent material of the type M’xM2-2xAX6doped with tetravalent manganese, wherein A comprises titanium.

4. The light generating system (1000) according to any one of the preceding claims, wherein the first luminescent material (210) comprises K2(Si1-xTix)F6:Mn4+, wherein x is selected from the range of ≥ 0.

6.

5. The light generating system (1000) according to any one of the preceding claims, wherein the first peak wavelength (λp1) is selected from the range of 500-510 nm, and the system light (1001) has a correlated color temperature selected from the range of 2000- 3400 K.

6. The light generating system (1000) according to any one of the preceding claims 1-4, wherein the first peak wavelength (λp1) is selected from the range of 510-520 nm, and the system light (1001) has a correlated color temperature selected from the range of 1500-2000 K.

7. The light generating system (1000) according to any one of the preceding claims, comprising one or more solid state light sources (100), wherein at least one of the one or more solid state light sources (100) comprises the first solid state light source (10), wherein each of the one or more solid state light sources (100) is configured to generate light source light (101) having a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm is in the wavelength range of 380-490 nm.

8. The light generating system (1000) according to any one of the preceding claims 1-4, further comprising a second solid state light source (20), wherein the second solid state light source (20) is configured to generate second light source light (21) having a second peak wavelength (λp2) selected from the range of 430-490 nm; wherein the luminescent converter (2000) is configured in a light receiving relationship with the second solid state light source (20); wherein the first luminescent material (210) is configured to convert at least part of the second light source light (21) received by the first luminescent material (210) into first luminescent material light (211).2024PF80190 41 9. The light generating system (1000) according to claim 7, wherein one or more applies of: the luminescent converter (2000) comprises at least 1.2 times an amount of the first luminescent material (210) needed to transmit at most 2% of the second light source light (21) received by the luminescent converter (2000); and the second peak wavelength (λp2) is selected from the range of 440-465 nm; wherein the luminescent converter (2000) comprises 2-5 times an amount of the first luminescent material (210) needed to transmit at most 2% of the second light source light (21) received by the luminescent converter (2000).

10. The light generating system (1000) according to any one of the preceding claims, wherein one or more applies of: the luminescent converter (2000) is configured in a transmissive mode; wherein the system light (1001) has a spectral power distribution, wherein ≤ 2% of the spectral power in the wavelength range of 380-780 nm is provided in the wavelength range of 380-490 nm; and the luminescent converter (2000) comprises the first luminescent material (210) in a first concentration C1, wherein the first concentration C1 is selected from the range of ≥ 20 vol%.

11. The light generating system (1000) according to any one of the preceding claims, wherein the luminescent converter (2000) comprises a second luminescent material (220), wherein the second luminescent material (220) is configured to convert part of the first light source light (11) received by the second luminescent material (220) into second luminescent material light (221); wherein the second luminescent material light (221) has a second centroid wavelength (λc2) selected from the range of 600-660 nm; wherein the second luminescent material light (221) comprises at least one emission band having a second full width at half maximum FWHM2of ≥ 60 nm; wherein the system light (1001) further comprises the second luminescent material light (221).

12. The light generating system (1000) according to claim 11, wherein the luminescent converter (2000) comprises (i) the first luminescent material (210) in a first concentration C1, and (ii) the second luminescent material (220) in a second concentration C2; wherein C2≤ C1.2024PF80190 42 13. The light generating system (1000) according to any one of the preceding claims, wherein one or more applies of: (a) the system light (1001) has a color point within 10 SDCM from the BBL in the CIE 1931 color space; and (b) the luminescent converter (2000) is configured at a non-zero distance (d1) from the first solid state light source (10).

14. The light generating system (1000) according to any one of the preceding claims, wherein one of the following applies: the light generating system (1000) comprises a Chip-on-Board (CoB) (500), wherein the Chip-on-Board (CoB) (500) comprises (i) a plurality of the first solid state light source (10), and (ii) the luminescent converter (2000), wherein the luminescent converter (2000) is configured on top of the plurality of first solid state light sources (10); and the light generating system (1000) comprises a LED filament (400), wherein the LED filament (400) comprises (i) a plurality of the first solid state light source (10) arranged on an elongated carrier (5), and (ii) an elongated encapsulant (410) configured in physical contact with and covering the plurality of first solid state light sources (10) and at least part of the elongated carrier (5); wherein the elongated encapsulant (410) comprises the luminescent converter (2000).

15. A lighting device (1200) selected from the group of a lamp (1) and a luminaire (2), comprising the light generating system (1000) according to any one of the preceding claims.

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