A light emitting device

Abstract

A light emitting device (1) configured to, in operation, emit device light (2) and comprising a first LED light source (3) configured to, in operation, emit first LED light source light (4) having a first peak emission wavelength, λ1, in a wavelength range of 380 nm to 420 nm, and a luminescent element (5) arranged in optical contact with the at least one first LED light source (3). The luminescent element (5) comprises a first luminescent material (6) configured to convert first LED light source light (4) into first luminescent material light (61) having a second peak emission wavelength, λ2, in a wavelength range of 420 nm to 490 nm and a first full-width-half-maximum, FWHM1, being larger than or equal to 50 nm, and a second luminescent material (7) configured to convert first luminescent material light (61) into second luminescent material light (71) having a third peak emission wavelength, λ3, in a wavelength range of 610 nm to 650 nm and a second full-width-half- maximum, FWHM2, being smaller than or equal to 40 nm. The second luminescent material (7) 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, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine. The device light (2) comprises a combination of part of the first luminescent material light (61) and the second luminescent material light (71).

Description

[0001] 2024PF80439

[0002] 1

[0003] A light emitting device

[0004] FIELD OF THE INVENTION

[0005] The invention relates to a light emitting device configured to, in operation, emit device light, the light emitting device comprising at least one first LED light source configured to, in operation, emit LED light source light having a first peak emission wavelength, I, and a luminescent element.

[0006] As used herein, the term “violet light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 380 nm to 420 nm.

[0007] As used herein, the term “blue light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 420 nm to 490 nm.

[0008] As used herein, the term “green-yellow light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 500 nm to 590 nm.

[0009] As used herein, the term “green light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 500 nm to 550 nm.

[0010] As used herein, the term “yellow light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 550 nm to 590 nm.

[0011] As used herein, the term “yellow-orange light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 550 nm to 600 nm.

[0012] As used herein, the term “red light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 600 nm to 680 nm.

[0013] As used herein, the term “white light” is intended to refer to light with correlated color temperature falling within the color temperature range of 2000 K to 9000 K, preferably in a correlated color temperature range of 2700 K to 6500 K.

[0014] As used herein, the term “cool white light” is intended to refer to light with correlated color temperature falling within the color temperature range of 3500 K to 6500 K.

[0015] As used herein, the term “extreme cool white light” is intended to refer to light with correlated color temperature falling within the color temperature range of 6500 K to 9000 K.

[0016] As used herein, the term “warm white light” is intended to refer to light with correlated color temperature falling within the color temperature range of 2000 K to 3500 K. 2024PF80439

[0017] 2

[0018] As used herein, the terms “upstream” and “downstream” are intended to be understood relative to the direction of propagation of light through the light generating system. In other words, when a first component or feature is arranged “downstream” of a second component or feature, it may be understood that the first component or feature is arranged in a light receiving relationship with the second component or feature.

[0019] BACKGROUND OF THE INVENTION

[0020] Light emitting devices with a phosphor-luminescent material is a technology of increasing importance due to that with the introduction of phosphors, such as KSiF, these LEDs are very efficient and provide high quality light, e.g., high red rendering.

[0021] However, the known types of such phosphor-luminescent material light emitting devices most often employs blue LEDs which comprise a narrow emission spectrum. This comes with a disadvantage in the form of a lower light quality.

[0022] It is therefore still desired to improve the light quality and / or eye safety of a phosphor-converted (pc) LED light source.

[0023] SUMMARY OF THE INVENTION

[0024] It is an object of the present invention to overcome this problem, and to provide a phosphor-converted (pc) LED light source with an improved light quality and / or eye safety.

[0025] According to a first aspect of the invention, this and other objects are achieved by means of a light emitting device configured to, in operation, emit device light, the light emitting device comprising: at least one first LED light source configured to, in operation, emit first LED light source light having a first peak emission wavelength, I, in a wavelength range of 380 nm to 420 nm, a luminescent element arranged in optical contact with the at least one first LED light source, the luminescent element comprising: a first luminescent material configured to convert at least a part of the first LED light source light into first luminescent material light having a second peak emission wavelength, X2, in a wavelength range of 420 nm to 490 nm and a first full-width-half-maximum, FWHM1, being larger than or equal to 50 nm, and a second luminescent material configured to convert a part of the first luminescent material light into second luminescent material light having a third peak emission wavelength, X3, in a wavelength range of 610 nm to 650 nm and a second full- width-half-maximum, FWHM2, being smaller than or equal to 40 nm, wherein the second luminescent material comprises a luminescent material of the type M’xM2-2xAX6 doped with 2024PF80439

[0026] 3 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, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine, and wherein the device light comprises a combination of a part of the first luminescent material light and the second luminescent material light.

[0027] Because the second luminescent material does not absorb green light, it is thereby obtained that only part of the blue luminescent material light emitted by the first luminescent material can be absorbed by the second luminescent material. Compared to using a blue LED, a first luminescent material has the advantage of comprising a broader emission spectrum, allowing both to excite the second luminescent material at its maximum excitation wavelength and to have part of the blue luminescent material light not being converted by the second luminescent material.

[0028] Furthermore, since the luminescent element may transmit a part of the LED light source light, and thus that the LED light source light is only partly converted by the luminescent element, the relatively continuous spectrum of the device light is extended to the violet light region.

[0029] Thereby, a light emitting device with an improved light quality and / or eye safety is provided for.

[0030] The at least one first LED light source may be configured to, in operation, emit first LED light source light having a first peak emission wavelength, XI, in a wavelength range of 400 nm to 420 nm.

[0031] Light in a wavelength range of 400 nm to 420 nm is (eye) safe for human beings. Thereby, safe violet light for improved white rendering is provided for.

[0032] The device light may further comprise non-converted first LED light source light.

[0033] Thereby, the relatively continuous spectrum of the device light is extended to the violet light region.

[0034] The at least one first LED light source may be configured to, in operation, emit first LED light source light having a first peak emission wavelength, I, in a wavelength range of 380 nm to 400 nm.

[0035] Thereby, an optimized excitation of the first luminescent material is obtained. In addition, light in a wavelength range of 380 nm to 400 nm can be used for disinfection.

[0036] The device light may be free from first light source light. For instance, less than 2 %, or less than 1 %, such as 0 %, of the device light may be the first light source light. 2024PF80439

[0037] 4

[0038] Thereby, the device light comprises blue (and optionally green-yellow) and red light, which in turn ensures relatively a continuous spectrum of the device light. Thereby, a light emitting device with an improved light quality and / or eye safety is provided for. Light quality may refer to one or more of color rendering index or improved red rendering.

[0039] The at least one first LED light source may comprise (i) a primary first LED light source configured to, in operation, emit primary first LED light source light having a primary first peak emission wavelength, XL, in a wavelength range of 380 nm to 400 nm, and (ii) a secondary first LED light source configured to, in operation, emit secondary first LED light source light having a secondary first peak emission wavelength, I”, in a wavelength range of 400 nm to 420 nm, and wherein XI”- XL > 10 nm or XI”- XL > 15 nm or XI”- XL > 20 nm.

[0040] Thereby, safe violet light for improved white rendering is provided for, and an optimized excitation of the first luminescent material is obtained.

[0041] The first luminescent material may be a phosphate-type luminescent material.

[0042] The second luminescent material may comprise a luminescent material of the type M2AX6 doped with tetravalent manganese, wherein A comprises Ti and one or more of Si and Gea tetravalent cation, for instance comprising one or more of silicon and titanium, and wherein A comprises at least 60% Ti.

[0043] The second luminescent material may be a KSiF-type luminescent material or a KTiF-type luminescent material.

[0044] Such luminescent materials are advantageous since a phosphate-type luminescent material has an emission spectrum which more optimally matches the excitation spectrum of a KTiF-type phosphor. The reason is that a KTiF-type has a right shifted excitation peak with respect to related KSiF phosphor types.

[0045] The second luminescent material may further comprise a second full-widthhalf-maximum, FWHM2, being smaller than or equal to 65 nm.

[0046] Thereby, device light with a broader spectrum is provided for.

[0047] The luminescent element may further comprise a third luminescent material configured to convert at least a part of the first luminescent material light into third luminescent material light having a fourth peak emission wavelength, X4, in a wavelength range of 500 nm to 590 nm or 520 nm to 570 nm, and wherein the device light further comprises the third luminescent material light. 2024PF80439

[0048] 5

[0049] By adding a third luminescent material, a light emitting device is obtained which provides device light with a relatively continuous spectrum due to the broad-band blue and green / yellow emission.

[0050] The device light may be white light having a correlated color temperature in a range from 1700 K to 6500 K (or from 1700K to 2500K) and a color rendering index of at least 80 (or at least 85).

[0051] The device light may be purplish red or reddish purple light. The obtained effect is improved efficiency.

[0052] The device light may be purplish red or reddish purple light defined by (u’, v’)-coordinates in the CIE 1976 U.C.S. Chromaticity Diagram as follows: Light in an area of the CIE 1976 U.C.S. Chromaticity Diagram defined by the following (u’, v’) color coordinates: (0.38, 0.47), (0.58, 0.46), (0.29, 0.37) and (0.40, 0.22).

[0053] The luminescent element may further comprise a fourth luminescent material configured to convert at least a part of the first luminescent material light into fourth luminescent material light having a fifth peak emission wavelength, 5, in a wavelength range of 610 nm to 660 nm and a fourth full-width-half-maximum, FWHM4, being larger than or equal to 50 nm or larger than or equal to 60 nm, and wherein the device light further comprises the fourth luminescent material light.

[0054] By adding a fourth luminescent material a light emitting device is obtained which provides device light with a continuous spectrum being extended into the red wavelength region.

[0055] The fourth luminescent material may be an (oxy)nitride luminescent material.

[0056] The third luminescent material may be a garnet class luminescent material.

[0057] Such luminescent materials are advantageous since such luminescent materials have emission spectra which more optimally matches the excitation spectrum of the types of first and second luminescent materials mentioned above.

[0058] The third luminescent material may further comprise a third full-width-half- maximum, FWHM3, being larger than or equal to 60 nm.

[0059] The fourth luminescent material may further comprise a fourth full-width-half- maximum, FWHM4, being larger than or equal to 60 nm.

[0060] Thereby, device light with a broader spectrum is provided for.

[0061] The luminescent element may comprise a stacked structure with (i) at first layer comprising the first luminescent material, and (ii) a second layer comprising the second luminescent material, and, where provided, the third luminescent material, and, where 2024PF80439

[0062] 6 provided, the fourth luminescent material, wherein the first layer is arranged downstream of the at least one first LED light source, and wherein the second layer is arranged downstream of the first layer. In case of a third luminescent material and / or a fourth luminescent material, they may also be arranged in one or more separate layers arranged downstream of the first (and second) layer.

[0063] Thereby, an improved light conversion in the luminescent element is provided for.

[0064] The light emitting device may be a LED filament or a chip-on-board lighting device.

[0065] The at least one first LED light source may comprise (i) a primary first LED light source configured to, in operation, emit primary first LED light source light having a primary first peak emission wavelength, XL, in a wavelength range of 380 nm to 400 nm, and (ii) a secondary first LED light source configured to, in operation, emit secondary first LED light source light having a secondary first peak emission wavelength, I”, in a wavelength range of 400 nm to 420 nm, and wherein XI”- XL > 10 nm, or wherein Xl”= XL, wherein the luminescent element is arranged downstream of the at least one primary first LED light source and downstream of the at least one secondary first LED light source.

[0066] In the case of Xl”= XL, device light of a higher intensity is provided for.

[0067] The first luminescent material and the second luminescent material may be provided in a part of the luminescent element arranged downstream of the at least one primary first LED light source.

[0068] The third luminescent material, and, where provided, the fourth luminescent material may be provided in a part of the luminescent element arranged downstream of the at least one secondary first LED light source.

[0069] By any of the above embodiments involving at least one primary first LED light source and at least one secondary first LED light source, a light emitting device is provided with which the light emitted by the at least one primary first LED light source and the at least one secondary first LED light source may complement each other such as to obtain white device light with a further improved light quality and / or eye safety.

[0070] The at least one first LED light source, or the primary first LED light source and the secondary first LED light source, and the luminescent element may be arranged on a substrate.

[0071] Thereby, a more robust light emitting device is provided for. 2024PF80439

[0072] 7

[0073] The at least one first LED light source, or the primary first LED light source and the secondary first LED light source, and the luminescent element may be arranged in a cup.

[0074] Thereby, better control of the direction of emission of the device light is obtained. Also, a more robust light emitting device is provided for.

[0075] The cup may comprise a reflective layer, coating or surface facing the at least one first LED light source, or the primary first LED light source and the secondary first LED light source, and the luminescent element.

[0076] Thereby, light losses which may otherwise occur by absorption in the cup may be avoided.

[0077] The invention further relates to a light emitting arrangement comprising a light emitting device according to the invention, and further comprising a controller configured to individually control the at least one first LED light source, or the primary first LED light source and the secondary first LED light source. Which such a configuration the spectral power distribution of the device light can be altered in order to vary, e.g., one or more of the color point, the correlated color temperature, the degree of white rendering, the color rendering index or the red rendering.

[0078] The invention further relates to a lamp comprising a light emitting device according to the invention.

[0079] The lamp may further comprise a light transmissive envelope at least partly enclosing the light emitting device and / or a base for electrically and mechanically connecting the lamp to a socket or a socket of a luminaire.

[0080] The invention further relates to a luminaire comprising a light emitting device according to the invention.

[0081] The invention still further relates to a luminaire comprising a lamp according to the invention. The luminaire may comprise a light exit window and / or a luminaire housing.

[0082] It is noted that the invention relates to all possible combinations of features recited in the claims.

[0083] BRIEF DESCRIPTION OF THE DRAWINGS

[0084] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention.

[0085] Fig. 1 shows a schematic, cross-sectional side view of a light emitting device according to the invention and comprising at least one first, violet, LED light source. 2024PF80439

[0086] 8

[0087] Fig. 2 shows a schematic, cross-sectional side view of another a light emitting device according to the invention and comprising at least one first, violet, LED light source.

[0088] Fig. 3 shows a schematic, cross-sectional side view of another a light emitting device according to the invention and comprising at least one first, violet, LED light source and at least one secondary first, violet, LED light source.

[0089] Fig. 4 shows a schematic, cross-sectional side view of another a light emitting device according to the invention and comprising at least one primary first, violet, LED light source and at least one secondary first, violet, LED light source.

[0090] Fig. 5 shows a schematic, cross-sectional side view of a light emitting arrangement comprising a light emitting device according to the invention.

[0091] Fig. 6 shows a graph illustrating the radiant power as a function of the wavelength of the device light obtained by a light emitting device according to the invention.

[0092] Fig. 7 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for a phosphate phosphor.

[0093] Fig. 8 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for a KSiF phosphor.

[0094] Fig. 9 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for a YAG phosphor.

[0095] Fig. 10 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for an (Oxy)Nitride phosphor.

[0096] Fig. 11 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for the combined spectra of the device light of a light emitting device comprising at least one first LED light source, a first luminescent material being a phosphate phosphor and a second luminescent material being a KSiF phosphor.

[0097] Fig. 12 shows a schematical side view of a lamp comprising a LED filament according to the invention.

[0098] Fig. 13 shows a schematical side view of a luminaire comprising a lamp and a LED filament according to the invention. 2024PF80439

[0099] 9

[0100] As illustrated in the figures, the sizes of layers and regions are exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout.

[0101] DETAILED DESCRIPTION

[0102] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and fully convey the scope of the invention to the skilled person.

[0103] Fig. 1 shows a schematic, cross-sectional side view of a light emitting device 1 according to the invention. Generally, and irrespective of the embodiment, the light emitting device 1 comprises at least one first LED light source 3 and a luminescent element 5. The light emitting device 1 is configured to, in operation, emit device light 2.

[0104] The at least one first LED light source 3 is configured to, in operation, emit LED light source light 4. The LED light source light 4 comprises a first peak emission wavelength, I, being in a wavelength range of 380 nm to 420 nm, or in a wavelength range of 400 nm to 420 nm. The at least one first LED light source 3 is a violet LED light source.

[0105] The luminescent element 5 is arranged downstream of the at least one first LED light source 3. The luminescent element 5 may be arranged in optical contact with the at least one first LED light source 3. The luminescent element 5 may be arranged in physical contact with the at least one first LED light source 3. The luminescent element 5 generally comprises at least two different luminescent materials 6 and 7.

[0106] The luminescent element 5 comprises a first luminescent material 6. The first luminescent material 6 is a blue luminescent material 6. The first luminescent material 6 may be a phosphate-type luminescent material. The first luminescent material 6 comprises a second peak emission wavelength, X2, in a range of 420 nm to 490 nm and a first full-widthhalf-maximum, FWHM1, being larger than or equal to 50 nm.

[0107] The luminescent element 5 further comprises a second luminescent material 7. The second luminescent material 7 comprises a luminescent material of the type M’XM2- 2XAXe 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 2024PF80439

[0108] 10 cation, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine. The second luminescent material 7 may be a KSiF-type or a KTiF-type luminescent material. The second luminescent material 7 comprises a third peak emission wavelength, 3, in a range of 610 nm to 650 nm, or of 610 nm to 660 nm. The second luminescent material 7 may further have a second full-width-half- maximum, FWHM2, being smaller than or equal to 40 nm, or being smaller than or equal to 65 nm.

[0109] For example, the first luminescent material 6 may be a phosphate-type luminescent material, and the second luminescent material 7 may comprise a luminescent material of the type M2AX6 doped with tetravalent manganese, wherein A comprises Ti and one or more of Si and Gea tetravalent cation, for instance comprising one or more of silicon and titanium, and wherein A comprises at least 60 % Ti. This may further optimize the excitation of the second luminescent material.

[0110] The luminescent element 5 is configured to receive the LED light source light 4. The luminescent element 5 is configured to convert at least a first part 41 of the LED light source light 4 into first luminescent material light 61 by the first luminescent material 6 (cf. Fig. 1). The luminescent element 5 is configured to convert a part of the first luminescent material light 61 into second luminescent material light 71 by the second luminescent material 7 (cf. Fig. 2). The luminescent element 5 may further be configured to convert at least a second part 42 of the LED light source light 4 into second luminescent material light 71 by the second luminescent material 7 (cf. Fig. 1). Finally, the luminescent element 5 is optionally configured to transmit a third part 43 of the LED light source light 4 (cf. Fig. 1).

[0111] The device light 2 therefore comprises a combination of the first luminescent material light 61 and the second luminescent material light 71, and optionally non-converted LED light source light 43. Fig. 11 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for the combined spectra of the device light 2 of a light emitting device 1 comprising at least one first LED light source 3, a first luminescent material 6 in the form of a phosphate phosphor, and a second luminescent material 7 in the form of a KSiF-type phosphor.

[0112] The luminescent element 5 further comprises an optional third luminescent material 8. The third luminescent material 8 is a green-yellow luminescent material. The third luminescent material 8 may be a garnet class luminescent material, such as for instance a YAG phosphor or a LuAG phosphor. The third luminescent material 8 comprises a fourth 2024PF80439

[0113] 11 peak emission wavelength, 4, in a range of 500 nm to 590 nm. The third luminescent material 8 may further comprise a third full-width-half-maximum, FWHM3, being larger than or equal to 60 nm. The luminescent element 5 is thereby further configured to convert at least a part of the first luminescent material light 61 into third luminescent material light 81 by the third luminescent material 8 (cf. Fig. 2). The luminescent element 5 may thereby further be configured to convert a fourth part 44 of the LED light source light into third luminescent material light 81 by the third luminescent material 8 (cf. Fig. 1).

[0114] The device light 2 then comprises a combination of the first luminescent material light 61, the second luminescent material light 71, the third luminescent material light 81, and optionally non-converted LED light source light 43. The device light 2 may then be white light having a correlated color temperature in a range from 1700 K to 6500 K and a color rendering index of at least 80.

[0115] The luminescent element 5 further comprises an optional fourth luminescent material 9. The fourth luminescent material 9 is a red luminescent material. The fourth luminescent material 9 may be an (oxy)nitride luminescent material. The fourth luminescent material 9 comprises a fifth peak emission wavelength, 5, in a range of 610 nm to 660 nm. The fourth luminescent material 9 may further comprise a fourth full-width-half-maximum, FWHM4, being larger than or equal to 60 nm. The luminescent element 5 is thereby further configured to convert at least a part of the first luminescent material light 61 into fourth luminescent material light 91 by the fourth luminescent material 9 (cf. Fig. 2). The luminescent element 5 may further be configured to convert a fifth part 45 of the LED light source light into fourth luminescent material light 91 by the fourth luminescent material 9 (cf. Fig. 1).

[0116] The device light 2 then comprises a combination of the first luminescent material light 61, the second luminescent material light 71, the third luminescent material light 81, the fourth luminescent material light 91, and optionally non-converted LED light source light 43.

[0117] It is also feasible that the luminescent element 5 of a light emitting device according to the invention may comprise a fourth luminescent material 9, but no third luminescent material 8. If so, the device light 2 then comprises a combination of the first luminescent material light 61, the second luminescent material light 71, the fourth luminescent material light 91, and optionally non-converted LED light source light 43. 2024PF80439

[0118] 12

[0119] In any event, the luminescent element 5 of the light emitting device l is a onelayered structure in which the different luminescent materials 6 and 7, as well as optionally 8 and / or 9, are distributed throughout all of, or at least a part of, the luminescent element 5.

[0120] Fig. 2 shows a schematic, cross-sectional side view of another light emitting device 100 according to the invention. The light emitting device 100 differs from the light emitting device 1 shown in Fig. 1 and described above in virtue of the following features.

[0121] The luminescent element 5 of the light emitting device 100 comprises a stacked structure with two layers, namely a first layer 51 and a second layer 52.

[0122] The first layer 51 comprises the first luminescent material 6. The first layer 51 is arranged downstream of the at least one first LED light source 3. The first layer 51 may be arranged in optical contact with the at least one first LED light source 3. The first layer 51 may be arranged in physical contact with the at least one first LED light source 3.

[0123] The second layer 52 comprises the second luminescent material 7, and, where provided, the third luminescent material 8 and / or the fourth luminescent material 9. The second layer 52 is arranged on top of the first layer 51. The second layer 52 is arranged downstream of the first layer 51. The first layer 51 is arranged between the at least one first LED light source 3 and the second layer 52. The second layer 52 may be arranged in optical contact with the first layer 51. The second layer 52 may be arranged in physical contact with the first layer 51.

[0124] As shown in Fig. 2, the device light may be free from non-converted first LED light source light 43.

[0125] It is also feasible that the luminescent element 5 of a light emitting device according to the invention may comprise more than two layers, such as one layer for each luminescent material provided. For example, a luminescent element 5 comprising a first luminescent material 6, a second luminescent material 7, and a third luminescent material 8 may comprise three layers. Likewise, a luminescent element 5 comprising a first luminescent material 6, a second luminescent material 7, and a fourth luminescent material 9 may comprise three layers. Also, a luminescent element 5 comprising a first luminescent material 6, a second luminescent material 7, a third luminescent material 8, and a fourth luminescent material 9 may comprise three or four layers.

[0126] Fig. 3 shows a schematic, cross-sectional side view of another light emitting device 101 according to the invention. The light emitting device 101 differs from the light emitting devices 1 and 100 shown in Figs. 1 and 2 and described above in virtue of the following features. 2024PF80439

[0127] 13

[0128] The at least one first LED light source 3 now comprises a primary first LED light source 3 ’ and a secondary first LED light source 3 ” . The primary first LED light source 3’ is configured to, in operation, emit primary first LED light source light 4’. The primary first LED light source light 4’ comprises a primary first peak emission wavelength, XL, in a wavelength range of 380 nm to 400 nm. The secondary first LED light source 3” is configured to, in operation, emit secondary first LED light source light 4”. The secondary first LED light source light 4” comprises a secondary first peak emission wavelength, I”, in a wavelength range of 400 nm to 420 nm. The primary first peak emission wavelength, XL, and the secondary first peak emission wavelength, XI”, may be chosen such that Xl”= XL.

[0129] The secondary first LED light source 3” is a violet LED light source.

[0130] The luminescent element 5 is arranged downstream of the primary first LED light source 3’ and the secondary first LED light source 3”. The luminescent element 5 may be arranged in optical contact with the primary first LED light source 3’ and the secondary first LED light source 3”. The luminescent element 5 may be arranged in physical contact with the primary first LED light source 3 ’ and the secondary first LED light source 3 ” . The luminescent element 5 comprises two parts 53 and 54. The first luminescent material 6 and the second luminescent material 7 is provided in the part 53 of the luminescent element 5 arranged downstream of or in optical contact with the at least one primary first LED light source 3’. Where provided, the third luminescent material 8 and / or the fourth luminescent material 9 is provided in the part 54 of the luminescent element 5 arranged downstream of or in optical contact with the at least one secondary first LED light source 3”.

[0131] Fig. 4 shows a schematic, cross-sectional side view of another light emitting device 102 according to the invention. The light emitting device 102 differs from the light emitting devices 1 and 100 shown in Figs. 1 and 2 and described above in virtue of the following features.

[0132] The at least one first LED light source 3 comprises a primary first LED light source 3’ and a secondary first LED light source 3”. The primary first LED light source 3’ is configured to, in operation, emit primary first LED light source light 4’. The primary first LED light source light 4’ comprises a primary first peak emission wavelength, XL, in a wavelength range of 380 nm to 400 nm. The secondary first LED light source 3” is configured to, in operation, emit secondary first LED light source light 4”. The secondary first LED light source light 4” comprises a secondary first peak emission wavelength, XI”, in a wavelength range of 400 nm to 420 nm. The primary first peak emission wavelength, 2024PF80439

[0133] 14

[0134] XL, and the secondary first peak emission wavelength, XI”, may be chosen such that XI”- XI’ > 10 nm.

[0135] Irrespective of the embodiment, the light emitting device 1, 100, 101, 102, may comprise an optional substrate 11 (cf. Figs. 1-4). Irrespective of the embodiment, the at least one first LED light source 3, or the primary first LED light source 3’ and the secondary first LED light source 3”, and the luminescent element 5 may be arranged on a substrate 11. The substrate 11 may for instance be a printed circuit board. The substrate 11 may comprise electrical wiring configured to provide the at least one first LED light source 3, or the primary first LED light source 3’ and the secondary first LED light source 3”, with electrical energy.

[0136] Irrespective of the embodiment, the light emitting device 1, 100, 101, 102, may comprise an optional cup 12 (cf. Figs. 1-4). Irrespective of the embodiment, the at least one first LED light source 3, or the primary first LED light source 3’ and the secondary first LED light source 3”, and the luminescent element 5 may be arranged in a cup 12. The cup 12 may be provided with a reflective layer or a coating on a surface 121 (cf. Fig. 4) of the cup 12 facing or being in physical contact with the luminescent element 5. The reflective layer or coating on the surface 121 is configured to ensure that light impinging on the surface 121 is reflected away from the at least one first LED light source 3.

[0137] Irrespective of the embodiment, the light emitting device 1, 100, 101, 102, may be a LED filament or a chip-on-board lighting device. It is also feasible that the light emitting device 1, 100, 101, 102, may comprise further light sources, such as at least one second light source.

[0138] Fig. 5 schematically shows a light emitting arrangement 200 according to the invention. The light emitting arrangement 200 comprises a light emitting device 1, 100, 101, 102 according to the invention. The light emitting arrangement 200 further comprises a controller 13. The controller 13 is configured to individually control the at least one first light source 3, or the primary first LED light source 3’ and the secondary first LED light source 3”.

[0139] Fig. 6 shows a graph illustrating the radiant power as a function of the wavelength of an exemplary device light 2 obtained by a light emitting device 1, 100, 101, 102 according to the invention and comprising a combination of the first luminescent material light 61, the second luminescent material light 71, the third luminescent material light 81, the fourth luminescent material light 91, and non-converted LED light source light 43. As may be seen from Fig. 4, the radiant power comprises a number of power peaks and 2024PF80439

[0140] 15 power ranges Pl to P8. The power peak Pl corresponds to the non-converted LED light source light 43. The power peak P2 corresponds to the first luminescent material light 61. The power peaks P4, P5 and P6 correspond to the second luminescent material light 71. The power peak P3 corresponds to the third luminescent material light 81. The power range P7 corresponds to the fourth luminescent material light 91. The power range P8 is formed (mainly) by a combination of the first luminescent material light 61 and the third luminescent material light 81.

[0141] Referring now to Figs. 7 to 10, different suitable phosphors for a light emitting device 1, 100, 101, 102 according to the invention will be described.

[0142] Phosphate class

[0143] Generally, phosphors of the phosphate class are suitable for use as the first luminescent material 6 of the luminescent element 5.

[0144] Phosphors of the phosphate class, or simply phosphate phosphors, are luminescent materials comprising a phosphate, PO4.

[0145] Fig. 7 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for a phosphate phosphor.

[0146] KSiF class

[0147] Generally, KSiF class phosphors are suitable for use as the second luminescent material 7 of the luminescent element 5.

[0148] KSiF class phosphors are luminescent materials 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, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine.

[0149] Relevant alkaline cations (M) are sodium (Na), potassium (K) and rubidium (Rb). Optionally, also lithium and / or cesium may be applied. In a preferred embodiment, M comprises at least potassium. In yet another embodiment, M comprises at least rubidium. The phrase “wherein M comprises at least potassium” indicates for instance that of all M cations in a mole M’xM2-2xAX6 , a fraction comprises K+and an optionally remaining fraction comprises one or more other monovalent (alkaline) cations (see also below). In another preferred embodiment, M comprises at least potassium and rubidium. Optionally, the M’xNfc- 2xAXe luminescent material has the hexagonal phase. In yet another embodiment, the M’xNfc- 2xAXe luminescent material has the cubic phase. For x=0, the composition is M2AX6. 2024PF80439

[0150] 16

[0151] Relevant alkaline earth cations (M’) are magnesium (Mg), strontium (Sr), calcium (Ca) and barium (Ba), especially one or more of Sr and Ba.

[0152] The term “tetravalent manganese” refers to Mn4+. This is a well-known luminescent ion. In the formula as indicated above, part of the tetravalent cation A (such as Si) is being replaced by manganese. Hence, M’xM2-2xAX6 doped with tetravalent manganese may also be indicated as M’xM2-2xAi-mMnmX6. The mole percentage of manganese, i.e. the percentage it replaces the tetravalent cation A will in general be in the range of 0.1-15 %, especially 1-12 %, i.e. m is in the range of 0.001-0.15, especially in the range of 0.01-0.12.

[0153] As indicated above, X relates to a monovalent anion, but at least comprises fluorine. Other monovalent anions that may optionally be present may be selected from the group consisting of chlorine (Cl), bromine (Br), and iodine (I).

[0154] In an embodiment, M’xM2-2xAX6 comprises K^SiFe (indicated herein also as KSiF system). As indicated above, in another preferred embodiment, M’xM2-2xAX6 comprises KRbSiFe (herein also indicated as K,Rb system). As indicated above, part of silicon is replaced by manganese (i.e. the formula may also be described as K2Sii-mMnmF6 or KRbSii-mMnmF6, with m as indicated above, or as KRbSiFe:Mn and K2SiFe:Mn, respectively). 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+).

[0155] In specific embodiments, the luminescent material may comprise (K,Rb)2SiFe:Mn4+. Alternatively, or additionally, in embodiments the third luminescent material may comprise K2SiFe:Mn4+. Alternatively, or additionally, in embodiments the third luminescent material may comprise K2TiFe:Mn4+. In embodiments, the third luminescent material may comprise K2(Si,Ti)Fe:Mn4+. As can be derived from the above, “Si,Ti” may indicate one or more of Si and Ti.

[0156] Fig. 8 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for a KSiF phosphor. KSiF phosphors can be effectively excited by a 460 nm blue LED with a strongest emission peak wavelength at near 631 nm, full width at half maxima (FWHM) smaller than 60nm with comparatively high color purity. Combined with P-SIAION green phosphor (cf. Fig. 8) for a backlight, NTSC can be improved to above 100 %. KSiF phosphors, as well as KTiF phosphors, are particularly suitable for use as the second luminescent material 7 of the luminescent element 5.

[0157] Garnet class 2024PF80439

[0158] 17

[0159] Generally, garnet class phosphors are suitable for use as the third luminescent material 8 of the luminescent element 5. Garnet class phosphors are luminescent materials of the type AsBsO Ce, wherein A in embodiments comprises one or more of Y, La, Gd, Tb and Lu, especially (at least) one or more of Y, Gd, Tb and Lu, and wherein B in embodiments comprises one or more of Al, Ga, In and Sc. Especially, A may comprise one or more of Y, Gd and Lu, such as especially one or more of Y and Lu. Especially, B may comprise one or more of Al and Ga, more especially at least Al, such as essentially entirely Al. Hence, especially suitable luminescent materials are cerium comprising garnet materials. Embodiments of garnets especially include A3B5O12 garnets, wherein A comprises at least yttrium or lutetium and wherein B comprises at least aluminum. Such garnets may be doped with cerium (Ce), with praseodymium (Pr) or a combination of cerium and praseodymium; especially however with Ce. Especially, B may comprise aluminum (Al); however, in addition to aluminum, B may also partly comprise gallium (Ga) and / or scandium (Sc) and / or indium (In), especially up to about 20% of B, more especially up to about 10 % of B (i.e. the B ions essentially consist of 90 or more mole % of Al and 10 or less mole % of one or more of Ga, Sc and In); B may especially comprise up to about 10% gallium. In another variant, B and O may at least partly be replaced by Si and N. The element A may especially be selected from the group consisting of yttrium (Y), gadolinium (Gd), terbium (Tb) and lutetium (Lu). Further, Gd and / or Tb are especially only present up to an amount of about 20% of A. In a specific embodiment, the garnet luminescent material comprises (Yi-xLux)3B50i2:Ce, wherein x is equal to or larger than 0 and equal to or smaller than 1. The term “:Ce”, indicates that part of the metal ions (i.e. in the garnets: part of the “A” ions) in the luminescent material is replaced by Ce. For instance, in the case of (Yi-xLux)3A150i2:Ce, part of Y and / or Lu is replaced by Ce. This is known to the person skilled in the art. Ce will replace A in general for not more than 10%; in general, the Ce concentration will be in the range of 0.1 to 4%, especially 0.1 to 2% (relative to A). Assuming 1% Ce and 10% Y, the full correct formula could be (Yo.iLuo.89Ceo.oi)3A150i2. Ce in garnets is substantially or only in the trivalent state, as is known to the person skilled in the art.

[0160] Fig. 9 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for one suitable garnet class phosphor, namely an Yttrium Aluminum Garnet (YAG) phosphor. YAG phosphors are efficient and suitable for creating a high correlated color temperature (CCT). YAG phosphors exhibit absorption peaks at 450 nm, and dominant emission wavelengths range from 540 nm - 560 nm. YAG phosphors can be effectively excited by a 2024PF80439

[0161] 18

[0162] 450 nm blue LED chip with an emission peak wavelength in the 540 nm - 560 nm range. YAG phosphors are mainly used for increasing luminous efficiency. By adding a small amount of a YAG yellow phosphor to an Ra80 LED, the luminous flux will increase dramatically. YAG phosphors are particularly suitable for use as the third luminescent material 8 of the luminescent element 5.

[0163] Another suitable garnet class phosphor is a Lutetium Aluminum Garnet (LuAG) phosphor. LuAG phosphors offer performance comparable to YAG phosphors. LuAG phosphors may have dominant emission wavelengths ranging from 520nm to 540 nm. LuAG phosphors are generally used in conjunction with red phosphors for high CRI full spectrum coverage. LuAG phosphors can be effectively excited by a 450nm blue LED with an emission peak wavelength in the 510-540 nm range. Combined with nitride red phosphor, a high CRI spectrum with Ra above 95 can be achieved. LuAG phosphors are particularly suitable for use as the third luminescent material 8 of the luminescent element 5.

[0164] (Oxy)Nitride class

[0165] Generally, (Oxy)Nitride phosphors are suitable for use as the fourth luminescent material 9 of the luminescent element 5.

[0166] (Oxy)Nitride phosphors are luminescent materials comprising NfcSis Eu2, or MAlSiN3:Eu2+or Ca2AlSi3O2Ns:Eu2+, etc., wherein M comprises one or more of Ba, Sr, and Ca, especially in embodiments at least Sr. Hence, in embodiments, the luminescent may comprise one or more materials selected from the group consisting of (Ba,Sr,Ca)S:Eu, (Ba,Sr,Ca)AlSiN3:Eu and (Ba,Sr,Ca)2SisN8:Eu. In these compounds, europium (Eu) is substantially or only divalent, and replaces one or more of the indicated divalent cations. In general, Eu will not be present in amounts larger than 10% of the cation; its presence will especially be in the range of about 0.5 to 10%, more especially in the range of about 0.5 to 5% relative to the cation(s) it replaces. The term “:Eu”, indicates that part of the metal ions is replaced by Eu (in these examples by Eu2+). For instance, assuming 2% Eu in CaAlSi Eu, the correct formula could be (Cao.98Euo.o2)AlSiN3. Divalent europium will in general replace divalent cations, such as the above divalent alkaline earth cations, especially Ca, Sr, or Ba. The material (Ba,Sr,Ca)S:Eu can also be indicated as MS:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound calcium or strontium, or calcium and strontium, more especially calcium. Here, Eu is introduced and replaces at least part of M (i.e. one or more of Ba, Sr, and Ca). Further, the material (Ba,Sr,Ca)2SisN8:Eu can also be indicated as NfcSis Eu, wherein M is one or more elements selected from the group consisting of 2024PF80439

[0167] 19 barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound Sr and / or Ba. In a further specific embodiment, M consists of Sr and / or Ba (not taking into account the presence of Eu), especially 50 to 100%, more especially 50 to 90% Ba and 50 to 0%, especially 50 to 10% Sr, such as Bai.sSro.sSis Eu (i.e. 75 % Ba; 25% Sr). Here, Eu is introduced and replaces at least part of M, i.e. one or more of Ba, Sr, and Ca). Likewise, the material (Ba,Sr,Ca)AlSiN3:Eu can also be indicated as MAlSi Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); especially, M comprises in this compound calcium or strontium, or calcium and strontium, more especially calcium. Here, Eu is introduced and replaces at least part of M (i.e. one or more of Ba, Sr, and Ca). Eu in the above indicated luminescent materials is substantially or only in the divalent state, as is known to the person skilled in the art.

[0168] Fig. 10 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (Em; solid line) and excitation (Ex; dashed line), respectively, for an (Oxy)Nitride phosphor.

[0169] Fig. 12 shows an exemplary lamp 300 comprising a light emitting device 1, 100, 101, 102, or a light emitting arrangement 200, according to any embodiment of the invention. In the embodiment shown, the light emitting device 1, 100, 101, 102 comprises a substantially straight light emitting device, such as a LED filament. The light emitting device of such a lamp may in other embodiments be a light emitting device with another shape, such as, but not limited to, spiral-shaped, helix-shaped, meandering, twisted, flat and combinations thereof.

[0170] The lamp 300 further comprises a driver or controller 305 configured for controlling the one or more LEDs 3, 3’, 3” of the light emitting device 1, 100, 101, 102. The controller 305 is configured to power the one or more LEDs 3, 3’, 3” via electrical circuitry (not visible on the figures) of the light emitting device 1, 100, 101, 102. The light emitting device 1, 100, 101, 102, or in particular the light emitting arrangement 200, may also comprise a controller 13, which may or may not be separate from the controller 305. In other words, the controller 305 and the controller 13 of the light emitting arrangement 200 may be integrated into one and the same driver or controller, or they may be mutually separate units.

[0171] The lamp 300 further comprises an envelope 301 at least partially enveloping the at least one light emitting device 1, 100, 101, 102. The lamp 300 further comprises a cap 303. As shown in Fig. 12, the controller 305 is arranged within the envelope 301. When comprising a cap 303, the controller 305 may also be arranged inside the cap 303 such that it 2024PF80439

[0172] 20 is hidden from view. The lamp 300 further comprises threading 302 for connection to a socket, and a terminal 304 for connection to a source of electrical energy.

[0173] The envelope 301 of the lamp 300 may further and optionally be provided with a coating (not shown), such as a reflective coating, covering at least a part of the envelope 301.

[0174] Turning finally to Fig. 13, an exemplary luminaire in the form of a pendant 400 is shown. The pendant 400 comprises a light emitting device 1, 100, 101, 102, or a light emitting arrangement 200, according to any embodiment of the invention. The light emitting device 1, 100, 101, 102 is as shown in Fig. 13 provided within a lamp 300 in the form of a light bulb. The light emitting device 1, 100, 101, 102 as shown in Fig. 10 comprises a substantially straight light emitting device, such as a LED filament.

[0175] As is also mentioned above, the light bulb further comprises a transparent envelope (cf. transparent envelope 301 of lamp 300) at least partially enveloping the at least one light emitting device 1, 100, 101, 102. The transparent envelope may be shaped in any feasible shape, for example such as to resemble the shape of any one of a standard light bulb, a globe light bulb, a candlelight bulb, a customized light bulb and even a spiral light bulb. The transparent envelope may comprise a luminescent material. The transparent envelope may be a glass envelope.

[0176] The pendant 400 further comprises a socket 401 for connecting the lamp 300, and thereby the light emitting device 1, 100, 101, 102, to the pendant 400. The socket 401 is adapted to cooperate with the base 303 of the lamp 300. The socket 401 may comprise a threading adapted to cooperate with the threading 302 of the lamp 300. The socket 401 may comprise a terminal adapted to cooperate with the terminal 304 of the lamp 300. The pendant 400 further comprises a reflector or screen 403.

[0177] The pendant 400 may further comprise a driver 402 configured for controlling the light emitting device 1, 100, 101, 102. The driver 402 may or may not be the same unit as the controller 305 described above. In other words, the driver 402 and the controller 305 may be integrated into one and the same driver or controller, or they may be mutually separate units. Alternatively, or additionally, the light emitting device 1, 100, 101, 102, or in particular the light emitting arrangement 200, may also comprise a controller 13, which may or may not be separate from one or both of the driver 402 and the controller 305.

[0178] As shown in Fig. 13, the driver 402 is arranged on a reflector or screen 403 of the pendant 400. The driver may also be arranged within or incorporated into the reflector or 2024PF80439

[0179] 21 screen 403. The pendant 400 further comprises an electrical wiring 404 for connection to a source of electricity, such as a mains.

[0180] It is noted that the pendant 400 shown in Fig. 13 is only one example of a luminaire according to the invention. Any suitable type of luminaire may be envisaged, such as but not limited to, a standing luminaire, a wall hung luminaire, a chandelier, a reading luminaire, an outdoor luminaire, and a table luminaire.

[0181] The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

Claims

2024PF8043922CLAIMS:

1. A light emitting device (1) configured to, in operation, emit device light (2), the light emitting device comprising: at least one first LED light source (3) configured to, in operation, emit first LED light source light (4) having a first peak emission wavelength, XI, in a wavelength range of 380 nm to 420 nm, a luminescent element (5) arranged in optical contact with the at least one first LED light source (3), the luminescent element comprising: a first luminescent material (6) configured to convert at least a part of the first LED light source light into first luminescent material light (61) having a second peak emission wavelength, X2, in a wavelength range of 420 nm to 490 nm and a first full-widthhalf-maximum, FWHM1, being larger than or equal to 50 nm, and a second luminescent material (7) configured to convert a part of the first luminescent material light (61) into second luminescent material light (71) having a third peak emission wavelength, X3, in a wavelength range of 610 nm to 650 nm and a second full- width-half-maximum, FWHM2, being smaller than or equal to 40 nm, wherein the second luminescent material (7) 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, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine, and wherein the device light (2) comprises a combination of a part of the first luminescent material light (61) and the second luminescent material light (71).

2. A light emitting device according to claim 1, wherein the at least one first LED light source (3) is configured to, in operation, emit first LED light source light (4) having a first peak emission wavelength, I, in a wavelength range of 400 nm to 420 nm, and wherein the device light further comprises non-converted first LED light source light (43).2024PF80439233. A light emitting device according to any one of the preceding claims, wherein the at least one first LED light source (3) is configured to, in operation, emit first LED light source light (4) having a first peak emission wavelength, I, in a wavelength range of 380 nm to 400 nm, and wherein the device light is free from first light source light.

4. A light emitting device according to any one of the preceding claims, wherein the at least one first LED light source (3) comprises (i) a primary first LED light source (3’) configured to, in operation, emit primary first LED light source light (4’) having a primary first peak emission wavelength, XL, in a wavelength range of 380 nm to 400 nm, and (ii) a secondary first LED light source (3”) configured to, in operation, emit secondary first LED light source light (4”) having a secondary first peak emission wavelength, XI”, in a wavelength range of 400 nm to 420 nm, and wherein XI”- XL > 10 nm.

5. A light emitting device according to any one of the above claims, wherein the first luminescent material (6) is a phosphate-type luminescent material, and wherein the second luminescent material (7) comprises a luminescent material of the type M2AX6 doped with tetravalent manganese, wherein A comprises Ti and one or more of Si and Gea tetravalent cation, for instance comprising one or more of silicon and titanium, and wherein A comprises at least 60 % Ti.

6. A light emitting device according to any one of the above claims, wherein the device light (2) further comprises non-converted LED light source light (43).

7. A light emitting device according to any one of the above claims, wherein the luminescent element further comprises a third luminescent material (8) configured to convert at least a part of the first luminescent material light (61) into third luminescent material light (81) having a fourth peak emission wavelength, X4, in a wavelength range of 500 nm to 590 nm, and wherein the device light (2) further comprises the third luminescent material light (81).

8. A light emitting device according to claim 7, wherein the device light (2) is white light having a correlated color temperature in a range from 1700 K to 6500 K and a color rendering index of at least 80.2024PF80439249. A light emitting device according to claim 1 to 6, wherein the device light (2) is purplish red or reddish purple light.

10. A light emitting device according to any one of the above claims, wherein the luminescent element further comprises a fourth luminescent material (9) configured to convert at least a part of the first luminescent material light (61) into fourth luminescent material light (91) having a fifth peak emission wavelength, 5, in a wavelength range of 610 nm to 660 nm and a fourth full-width-half-maximum, FWHM4, being larger than or equal to 50 nm, and wherein the device light (2) further comprises the fourth luminescent material light (91).

11. A light emitting device according to any one of claims 7 to 10, wherein one or more of the following applies: the fourth luminescent material (9) is an (oxy)nitride luminescent material, and the third luminescent material (8) is a garnet class luminescent material.

12. A light emitting device according to any one of the preceding claims, wherein the luminescent element (5) comprises a stacked structure with (i) a first layer (51) comprising the first luminescent material (6), and (ii) a second layer (52) comprising the second luminescent material (7), and optionally the third luminescent material (8), and optionally the fourth luminescent material (9), wherein the first layer (51) is arranged downstream of the at least one first LED light source (3), and wherein the second layer (52) is arranged downstream of the first layer.

13. A light emitting device according to any one of the preceding claims, wherein the light emitting device is a LED filament or a chip-on-board lighting device.

14. A light emitting arrangement (200) comprising a light emitting device (1, 100, 101, 102) according to any one of claims 4 to 13, and further comprising a controller (13) configured to individually control the primary first LED light source (3’) and the secondary first LED light source (3”).2024PF804392515. A lamp or a luminaire comprising a light emitting device (1, 100, 101, 102) according to any one of claims 1-13 or a light emitting arrangement according to claim 14.

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